Uninsurance and Health Care Access Among Young Adults in the United States
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《小儿科》
Division of Adolescent Medicine and Behavioral Science
Division of General Pediatrics and the Center for Health Services Research, Department of Pediatrics, Vanderbilt University Medical Center, Nashville, Tennessee
ABSTRACT
Objective. Young adults who are 19 to 24 years of age are the most likely age group to be uninsured in the United States, yet little is known about how uninsurance might affect health care access among young adults. The objective of this study was to describe the association between health insurance status and health care access among young adults while controlling for other determinants of access to care.
Methods. We conducted a cross-sectional analysis of data from 11 866 19- to 24-year-old respondents who completed the National Health Interview Survey between 1998 and 2001. We present percentages and adjusted relative risk of young adults who in the previous year delayed or missed medical care because of cost, did not fill a prescription because of cost, had not spoken to a health professional, or identified no usual source of health care.
Results. Among the young adults studied, 27% of women and 33% of men were uninsured. After potential confounders were adjusted for, the uninsured remained at significantly higher risk for reporting delayed or missed medical care (women: adjusted relative risk [95% confidence interval]: 3.24 [2.72–3.82]; men: 4.31 [3.44–5.34]), not filling a prescription because of cost (women: 3.27 [2.55–4.16]; men: 4.05 [2.78–5.81]), having no contact with a health professional (women: 2.54 [2.01–3.09]; men: 1.60 [1.43–1.77]), and having no usual source of health care (women: 3.45 [3.05–3.90]; men: 2.27 [2.06–2.48]) relative to privately insured peers. Women with Medicaid did not differ significantly from privately insured women in these measures.
Conclusions. Uninsured young adults were significantly more likely than privately insured peers to report barriers to obtaining needed care, having no contact with a health professional, and identifying no usual source of health care. Given the high rates of uninsurance among young adults, additional study is needed to examine how these barriers affect the immediate and future health of the young adult.
Key Words: access to health care adolescent medicine uninsured young adults
Abbreviations: NHIS, National Health Interview Survey HMO, health maintenance organization SCHIP, State Children’s Health Insurance Plan AOR, adjusted odds ratio CI, confidence interval
Young adults who are 19 to 24 years of age are the most likely age group to be uninsured in the United States.1 Almost one third of young adults are currently uninsured, and an even higher proportion experience gaps in health care coverage during young adulthood.2,3 Young adults experience uninsurance as they age out of public or private health insurance coverage held as children. Nearly half of employed young adults will hold employment that does not offer health insurance coverage.4 Working young adults are more than twice as likely as older working adults to live in poverty5; therefore, many will be unable to afford health insurance independently. At highest risk for uninsurance are young men, Hispanic young adults, the poor and near-poor, and nonstudents who are not working or who work in jobs that do not offer health insurance.2,4,6,7 Little is known about how uninsurance affects access to health care for young adults.
The consequences of uninsurance among young adults warrant focused study for several reasons. Young adulthood is a high-risk period for unintended pregnancy, sexually transmitted infections, substance abuse, and injuries; and an increasing number of young adults have chronic medical conditions.8–12 Relative to older adults, younger adults have fewer financial resources (and less ability to withstand the impact of health care costs).13 Finally, young adults are less likely than older adults to participate actively in local and national political debates regarding health insurance coverage.14 For these reasons, information about the impact of uninsurance among young adults is necessary to inform pediatric and adult health care providers as well as policy makers who strive to improve health care services for this population.
Although overrepresented among the uninsured, young adults are underrepresented in studies of the consequences of uninsurance. Uninsurance among adults has been associated with less frequent screening and delayed diagnosis of cancer, substandard care of chronic diseases, and increased death when hospitalized.15,16 These outcomes are important but have limited immediate relevance to the majority of young adults. Uninsurance has also been linked to the inability to secure medical services when needed,17–20 an outcome particularly relevant to young adults. In a study of working-age adults from the Centers for Disease Control and Prevention, younger adults (18–44 years of age) were more likely than older adults (45–64 years of age) to report delaying medical care because of cost (13% vs 11%).20 A study by the Commonwealth Fund found that half of uninsured 18- to 29-year-olds in low-income households experienced a time in the previous year when they needed health care but could not afford it.2 An analysis of data from Massachusetts showed that young adults were more likely to report being unable to afford needed health care when they were uninsured (women: 43%; men: 26%) than if they had health insurance (women: 14%; men: 5%).7 Access to care has also been shown to be influenced by other socioeconomic factors, such as race/ethnicity and income.17 Studies that account for these potential confounders are needed to improve our understanding of the consequences of uninsurance among young adults. The specific aims of this study were to describe the association of health insurance status and health care access among young adults while controlling for socioeconomic and health factors that may influence access to care.
METHODS
Data Source
We analyzed data from the National Health Interview Survey (NHIS), an ongoing cross-sectional national household survey sponsored by the National Center for Health Statistics and conducted by the US Census Bureau and the Centers for Disease Control and Prevention. The purpose of the NHIS is to collect information on the health status and use of health services by the US civilian noninstitutionalized population.21 The sampling plan uses a multistage area probability design to yield nationally representative estimates. Weights are provided to adjust the sample data to reflect the age, gender, and race distribution of the US population. We examined responses for young adults who were aged 19 to 24 years and completed the NHIS for the last 4 years for which data were available (1998, 1999, 2000, and 2001). Using formulas provided by NHIS,21 we calculated a response rate of 71.7% for all adults selected for the sample adult questionnaire during the 4 years studied.
The NHIS consists of a group of surveys that collect data on households and individuals. Data are released for public use in several data files. For this study, data for each respondent were drawn from the person-level file (containing sociodemographic and basic health information for each member of a household collected directly from individuals or from other adult members of the household if the individual is not at home or is unable to answer) and from the sample adult file (containing additional health, health care utilization, and behavior data obtained from 1 randomly selected adult in each household).
Description of Variables Used
Health Care Access Variables
The dependent variables in these analyses were 4 health care access variables that categorized young adults according to whether they reported that they (1) delayed or missed health care because of cost in the previous 12 months, (2) failed to have a prescription filled because of cost in the previous 12 months, (3) had no usual source of health care, or (4) had no contact with a health professional in the previous 12 months. For these analyses, respondents were said to have a usual source of care when they reported usually going to a clinic, health center, doctor's office or health maintenance organization (HMO), hospital outpatient department, or some other place when they were sick or needed health advice. In this context, HMO refers to a staff model HMO in which providers see patients in the HMO's own facilities.22 Young adults without a usual source of health care were those who did not identify a usual source or who identified the emergency department as their usual source of care.
Health Insurance Coverage
We used survey data to identify health insurance coverage at the time of the interview. For these analyses, the uninsured were young adults who reported having no coverage through private health insurance, Medicare, Medicaid, State Children's Health Insurance Plan (SCHIP), Civilian Health and Medical Program for Uniformed Services, the Indian Health Service, or other public programs. Because of insufficient numbers for analyses, we excluded the 2.6% of male respondents who reported having Medicaid and young adults who reported having insurance coverage other than private insurance or Medicaid (1.7% of men; 2.7% of women). Also excluded were young adults for whom insurance information was missing (1.2% of men; 1.2% of women) and the few young adults who reported having both public and private insurance (0.1% of men; 0.1% of women). Young adults who reported being uninsured or having private insurance or Medicaid (women only) were included in univariate and multivariate analyses.
Sociodemographic and Health Variables
We used the survey to ascertain the young adults' highest level of educational attainment, marital status, household income, and major activity in the week before the survey. The NHIS provided recoded variations of these survey items by collapsing responses to original questionnaire items or by combining responses to >1 variable. After examining frequencies and univariate associations with the health care access variables, we further collapsed response categories to preserve adequate numbers for analyses. The young adults' highest level of educational attainment was collapsed to < 8th grade, 9th to 12th grade (no diploma), high school graduate, General Educational Development (GED) recipient, or some college (including those with or without a degree). Marital status was recoded to single (including those who were never married and those who were widowed or divorced), married (including those who were separated), and unmarried but living with a partner. Household income included income from all sources and was provided as a ratio of income to the US Census Bureau's poverty threshold for the survey year after considering overall family size and number of children in the household.23 For reference, the 2001 poverty threshold was $11 859 for a 2-person household and $17 960 for a 4-person household (2 adults, 2 children).23 Young adults were asked whether they were working at a job or business in the previous week. Those who were not working were asked why they were not working. From this information, the NHIS constructed a major activity variable that separated respondents into 4 categories: working at a job or business, going to school, keeping house, and something else. The few men who reported keeping house were included in the "something else" category. We used recoded NHIS variables to determine whether the young adult had an activity limitation attributable to a chronic medical condition.
Data Analysis
We present univariate analyses showing the relationship between insurance status and health care access variables. We found significant differences between men and women in insurance status and each of the health care access variables; therefore, all analyses were stratified by gender. We present multiple logistic regression models for each health care access (dependent) variable to assess the association between the dependent variable and insurance status while controlling for sociodemographic/health variables, yielding adjusted odds ratios (AORs) and 95% confidence intervals (CIs). When main outcomes are common in a population, as in this study, AORs may overestimate risk ratios that are >1 and underestimate risk ratios that are <1. To improve our estimation of true risk ratios, we present adjusted relative risks and 95% CIs as described by Zhang and Yu.24 Final analyses were conducted by using SUDAAN (Research Triangle Institute, Research Triangle Park, NC) to account for the complex sampling design and clustering of data in the NHIS.25
Among young adults, 21% did not provide complete income data. Compared with participants for whom income data were available, those who did not provide income data were more likely to be uninsured, be a member of a racial or ethnic minority, and have lower educational attainment. Those who did not provide income data were also more likely to report that they had not seen a provider in the previous year but were less likely to report delaying health care because of cost. Men but not women who did not provide income data were more likely to report having no usual source of health care. We analyzed regression models with and without the income variable. Both methods yielded similar results; therefore, we present final regression models including household income, race/ethnicity, highest level of educational attainment, major activity in the previous week, marital status, limitation of activity as a result of a chronic medical condition, and pregnancy (women only). The study protocol was approved by the Vanderbilt University Institutional Review Board (Nashville, TN).
RESULTS
Univariate and Bivariate Analyses
The total number of 19- to 24-year-old participants was 11 866. Half of the weighted sample were female, and approximately two thirds were white non-Hispanic (Table 1). In univariate analyses, there were significant between-gender differences in insurance status and the health care access measures (Table 2). One third of young men reported being uninsured, 62% reported being privately insured, and <3% reported coverage through Medicaid. Young women were less likely than men to report being uninsured (27% vs 33%; P < .0001) but also less likely to have private health insurance (58% vs 62%; P < .0001). Nearly 11% of women reported having coverage through Medicaid. Young women were significantly more likely than men to report delaying or missing medical care because of cost or failing to fill a prescription because of cost. Men were significantly more likely to report that they had no usual source of health care and had no contact with a health professional in the previous year.
Uninsured young adults of both genders were significantly more likely than their insured peers to report delaying or missing health care because of cost, failing to fill a prescription because of cost, having no contact with a health professional in the previous year, and having no usual source of health care (Fig 1). Young women with Medicaid did not differ significantly from privately insured women in these measures.
Multivariate Analyses
Multiple logistic regression models for each of the health care access variables studied are presented for women and men (Tables 3 and 4). Relative to insured young women, uninsured women had >3 times the adjusted risk of reporting delayed or missed medical care or failure to fill a prescription because of cost in the previous year. Uninsured women had more than twice the adjusted risk of reporting no contact with a health professional and >3 times the adjusted risk of reporting no usual source of health care relative to insured women. After adjustment, women with Medicaid did not have a higher risk of reporting any of these potential barriers relative to privately insured peers.
Findings for uninsured young men were similar to those for women. Uninsured men had 4 times higher adjusted risk of reporting delayed or missed care or failure to fill a prescription relative to privately insured men. Uninsured men had significantly higher risk of reporting having had no contact with a health professional in the previous year and having no usual source of health care.
Household income and race/ethnicity were also significantly associated with many of the reported health access variables in multivariate regression models. In general, lower household income was associated with higher adjusted risk of reporting health care access barriers for both genders. Relative to young men in the highest household income category (5 times the poverty level), men in households with income 0 to 3 times the poverty level were at significantly higher risk of reporting delayed or missed medical care because of cost, having no contact with a health provider, and having no usual source of care. Relative to women in the highest income category, women in all other income categories were at significantly higher risk of reporting delayed or missed medical care, whereas only those with an income between 2 and 3 times the poverty level were at significantly higher risk of reporting no visit in the last year, and women in households with income <2 times the poverty level were at significantly higher risk of reporting no usual source of care.
Relative to white non-Hispanic women, Hispanic women had significantly lower risk of reporting delayed or missed medical care but significantly higher risk of reporting having had no contact with a health professional in the previous year and having no usual source of health care. Among young men, race/ethnicity was significantly associated with each of the health care access variables. Relative to white men, Hispanic men had significantly lower adjusted risk of reporting delayed or missed medical care and significantly higher adjusted risk of reporting having had no contact with a health professional and having no usual source of health care. The risk of reporting delayed or missed medical care was also significantly lower for black men relative to white men.
In data not shown, young men and women who reported activity limitation as a result of a chronic medical condition had higher adjusted risk of reporting delayed or missed medical care because of cost and lower adjusted risk of reporting having no usual source of care and having had no contact with a medical provider relative to same-gender young adults without activity limitation as a result of a chronic medical condition.
DISCUSSION
Despite the perception of robust health, many young adults in this study reported health care needs for which care was delayed or foregone because the young adult was unable to afford it; this was particularly true among those who reported being uninsured. One in 4 uninsured women and 1 in 5 uninsured men in this study reported that they delayed or missed needed health care in the previous year because of cost. These numbers are particularly concerning given the high rates of uninsurance among young adults.1 Whereas some young adults who delay medical care may find that the underlying medical complaint is self-limited, others will be at risk for worsening symptoms or sequelae as a result of delayed diagnosis or treatment. For example, the young woman who delays care for symptoms caused by Chlamydia may spread the infection to other sexual partners, develop pelvic inflammatory disease, and increase her risk for having impaired fertility.26,27 Even when health care is received, uninsurance may have an impact on the young adult's ability to adhere to medical treatment. In our study, uninsured young adults were at significantly increased risk for failing to fill a prescription because of cost in the previous year.
Uninsured young adults were also significantly more likely to report that they had not had recent contact with a health professional. This may translate into fewer opportunities for uninsured young adults to receive recommended preventive screening and clinical services. Preventive health interventions including cessation counseling for tobacco and alcohol use and screening for certain sexually transmitted infections have proven efficacy among young adults, yet available data indicate that fewer than half of eligible young adults receive these interventions.28
Potentially compromising the young adult's access to health care further is the absence of a regular source of health care. More than 40% of uninsured young women and >60% of uninsured young men in our study lacked a usual source of health care. In comparison, the National Center for Health Statistics reported that 46% of all uninsured 18- to 64-year-olds in the 2000–2001 NHIS had no usual source of care.29 Depending on methods, others have reported that 16% to 40% of uninsured American adults lack a regular source of health care.17,18,20,30 These studies and others have shown that adults without a usual source of care are less likely to receive preventive services and are more likely to have fragmented care than those with a usual source of care; this is particularly true when they are concomitantly uninsured.31,32 Young adults without a usual source of care may have few options other than emergency department use for acute medical problems. This may contribute to further crowding of emergency centers and higher health care costs.33
Young women with Medicaid were not significantly more likely than privately insured women to report inability to obtain needed care, having no contact with a health provider, or having no usual source of care. This finding is particularly important given that 21% of the young women with Medicaid in this study reported that they were currently pregnant. Other studies have demonstrated that access to health care (including prenatal care) for the population with Medicaid coverage is generally better than access for those who are uninsured but not as good as for those with private health insurance.18,34–36 State-specific variability in Medicaid programs, limitations in health care providers who accept Medicaid, and difficulties obtaining or retaining Medicaid coverage are likely to make this coverage less optimal than private insurance; however, this study suggests that Medicaid has an important role in reducing access barriers for young women.
As expected, other socioeconomic factors were significantly related to health care access in this population. Predictably, lower household income was associated with increased risk of reporting barriers to health care access among young adults. Although the public may assume that only the poor experience barriers to health care access, the findings of this study suggest that young adults who live in households with incomes 2 to 3 times the poverty level are at higher risk of reporting barriers relative to young adults in the highest income level. This encompasses nearly half of the young adults in this study who provided income data. Variability in living situations, occupational or educational roles, and dependence on parents all are hallmarks of young adulthood that may affect this population's household income.37
We also found that Hispanic young adults were significantly less likely than those who are non-Hispanic white to report delayed medical care but significantly more likely to report having no contact with a health professional and having no usual source of health care. These findings are consistent with findings from a recent study by Weinick et al38 demonstrating that Hispanic (as well as black) Americans were less likely than those who are non-Hispanic white to use ambulatory services or have a usual source of health care. As in our study, these disparities persisted even after controlling for income and health insurance coverage. Other unmeasured socioeconomic factors, differences in actual or perceived health, or cultural factors may help to explain the disparities in health care use for this population. Given the considerable growth and heterogeneity of the population of Hispanic young adults in the United States, understanding disparities in health care access for this population warrants specific study. Our study suggests that eliminating disparities in health care access for Hispanic young adults will necessitate measures beyond improving health insurance coverage and reducing financial barriers.
Despite the millions affected, uninsurance among young adults has historically garnered little attention as a policy issue, largely because young adults are the least likely age segment of the population to vote and have few identified advocacy groups. Nearly 70% of eligible older adults voted in the 2000 presidential election, but only 36% of eligible young adults did so.39 Motivated in part by a desire to increase the political participation of this group, issues that are relevant to health care access for young adults, particularly uninsurance, have received more attention on Capitol Hill. The focus of this attention is groups of young adults who previously have been shown to be at higher risk of uninsurance, including poor and near-poor young adults and young adults who work in jobs that do not offer health insurance.2,4,6,7 The Medicaid/SCHIP Optional Coverage for Young Adults Act (HR 3192) was introduced in the House of Representatives by Congressman Vic Snyder (D-AR) in 2003 and would allow states to extend coverage to low-income young adults up to age 23 with an enhanced matching rate.40 A companion bill (S 1889) was subsequently introduced in the Senate.41 In 2004, the US Senate Republican Task Force on Health Care Costs and the Uninsured released a proposal to increase health insurance coverage with specific recommendation for young adults, including developing incentives for young adults to purchase lifetime, portable insurance and increasing the availability of health savings accounts.42 As part of his presidential platform, Senator John Kerry proposed to extend Medicaid and SCHIP coverage to low-income young adults. In addition, both Senator Kerry and President George W. Bush advanced campaign proposals that included provisions to facilitate the purchase of health insurance coverage for employees of small businesses, many of whom are young adults. These activities on behalf of young adults are promising but have yet to result in actual policy change. As noted earlier, improving insurance coverage for young adults may facilitate access to health care; however, more will need to be done to eliminate disparities in health care access for certain young adult populations.
Within the health care sector, there are also relatively few organized proponents for young adults. Young adults may receive health care from providers who specialize in pediatric, family, adult, emergency, and women's health care but are unlikely to constitute a substantial proportion of the patient population of any of these health care groups. Organized efforts of health care providers are necessary to increase public awareness of the high rates of uninsurance and barriers to health care access for young adults. Individually, health care providers may have opportunities to assist young adult patients in obtaining or retaining health insurance coverage. Potential interventions include providing anticipatory guidance to older adolescents and their parents regarding future plans for health insurance coverage, discussing the importance of health insurance coverage with young adult patients, and helping young adults locate available resources. In addition, health care providers should be mindful that opportunities to provide preventive services for young adults may be scarce. For some, an office visit for an acute medical complaint may be the only opportunity that the provider has to screen for other conditions or behaviors that place the young adult's health at risk.
Our study has several limitations. The NHIS is based on self-report or the report of other members of the household and may be subject to recall error. We calculated that 28% of those selected as sample adults did not complete the survey, and this nonresponse may contribute bias. We were unable to validate insurance status through another source, and measures of health insurance adequacy or inquiries about gaps in insurance coverage among the currently insured were not included. Finally, the cross-sectional nature of this study does not allow us to determine that lack of health insurance caused the reported health access barriers or to determine the immediate or long-term health outcomes resulting from the reported delayed or foregone care.
CONCLUSIONS
The findings from this study demonstrate that 19- to 24-year-olds who lack health insurance face significant barriers to obtaining health care when they need it. Even after sociodemographic and health characteristics were adjusted for, uninsured young adults were significantly more likely than the privately insured to report being unable to obtain needed care, having no contact with a health professional in the previous year, and having no usual source of health care. Given the high rates of uninsurance among young adults, additional study is needed to examine how these barriers affect the immediate and future health of the young adult.
FOOTNOTES
Accepted Oct 14, 2004.
No conflict of interest declared.
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Research Triangle Institute. SUDAAN User's Manual, Release 8.0. Research Triangle Park, NC: Research Triangle Institute; 2002
Hillis SD, Joesoef R, Marchbanks PA, Wasserheit JN, Cates W Jr, Westrom L. Delayed care of pelvic inflammatory disease as a risk factor for impaired fertility. Am J Obstet Gynecol. 1993;168 :1503 –1509
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Coffield AB, Maciosek MV, McGinnis JM, et al. Priorities among recommended clinical preventive services. Am J Prev Med. 2001;21 :1 –9
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Division of General Pediatrics and the Center for Health Services Research, Department of Pediatrics, Vanderbilt University Medical Center, Nashville, Tennessee
ABSTRACT
Objective. Young adults who are 19 to 24 years of age are the most likely age group to be uninsured in the United States, yet little is known about how uninsurance might affect health care access among young adults. The objective of this study was to describe the association between health insurance status and health care access among young adults while controlling for other determinants of access to care.
Methods. We conducted a cross-sectional analysis of data from 11 866 19- to 24-year-old respondents who completed the National Health Interview Survey between 1998 and 2001. We present percentages and adjusted relative risk of young adults who in the previous year delayed or missed medical care because of cost, did not fill a prescription because of cost, had not spoken to a health professional, or identified no usual source of health care.
Results. Among the young adults studied, 27% of women and 33% of men were uninsured. After potential confounders were adjusted for, the uninsured remained at significantly higher risk for reporting delayed or missed medical care (women: adjusted relative risk [95% confidence interval]: 3.24 [2.72–3.82]; men: 4.31 [3.44–5.34]), not filling a prescription because of cost (women: 3.27 [2.55–4.16]; men: 4.05 [2.78–5.81]), having no contact with a health professional (women: 2.54 [2.01–3.09]; men: 1.60 [1.43–1.77]), and having no usual source of health care (women: 3.45 [3.05–3.90]; men: 2.27 [2.06–2.48]) relative to privately insured peers. Women with Medicaid did not differ significantly from privately insured women in these measures.
Conclusions. Uninsured young adults were significantly more likely than privately insured peers to report barriers to obtaining needed care, having no contact with a health professional, and identifying no usual source of health care. Given the high rates of uninsurance among young adults, additional study is needed to examine how these barriers affect the immediate and future health of the young adult.
Key Words: access to health care adolescent medicine uninsured young adults
Abbreviations: NHIS, National Health Interview Survey HMO, health maintenance organization SCHIP, State Children’s Health Insurance Plan AOR, adjusted odds ratio CI, confidence interval
Young adults who are 19 to 24 years of age are the most likely age group to be uninsured in the United States.1 Almost one third of young adults are currently uninsured, and an even higher proportion experience gaps in health care coverage during young adulthood.2,3 Young adults experience uninsurance as they age out of public or private health insurance coverage held as children. Nearly half of employed young adults will hold employment that does not offer health insurance coverage.4 Working young adults are more than twice as likely as older working adults to live in poverty5; therefore, many will be unable to afford health insurance independently. At highest risk for uninsurance are young men, Hispanic young adults, the poor and near-poor, and nonstudents who are not working or who work in jobs that do not offer health insurance.2,4,6,7 Little is known about how uninsurance affects access to health care for young adults.
The consequences of uninsurance among young adults warrant focused study for several reasons. Young adulthood is a high-risk period for unintended pregnancy, sexually transmitted infections, substance abuse, and injuries; and an increasing number of young adults have chronic medical conditions.8–12 Relative to older adults, younger adults have fewer financial resources (and less ability to withstand the impact of health care costs).13 Finally, young adults are less likely than older adults to participate actively in local and national political debates regarding health insurance coverage.14 For these reasons, information about the impact of uninsurance among young adults is necessary to inform pediatric and adult health care providers as well as policy makers who strive to improve health care services for this population.
Although overrepresented among the uninsured, young adults are underrepresented in studies of the consequences of uninsurance. Uninsurance among adults has been associated with less frequent screening and delayed diagnosis of cancer, substandard care of chronic diseases, and increased death when hospitalized.15,16 These outcomes are important but have limited immediate relevance to the majority of young adults. Uninsurance has also been linked to the inability to secure medical services when needed,17–20 an outcome particularly relevant to young adults. In a study of working-age adults from the Centers for Disease Control and Prevention, younger adults (18–44 years of age) were more likely than older adults (45–64 years of age) to report delaying medical care because of cost (13% vs 11%).20 A study by the Commonwealth Fund found that half of uninsured 18- to 29-year-olds in low-income households experienced a time in the previous year when they needed health care but could not afford it.2 An analysis of data from Massachusetts showed that young adults were more likely to report being unable to afford needed health care when they were uninsured (women: 43%; men: 26%) than if they had health insurance (women: 14%; men: 5%).7 Access to care has also been shown to be influenced by other socioeconomic factors, such as race/ethnicity and income.17 Studies that account for these potential confounders are needed to improve our understanding of the consequences of uninsurance among young adults. The specific aims of this study were to describe the association of health insurance status and health care access among young adults while controlling for socioeconomic and health factors that may influence access to care.
METHODS
Data Source
We analyzed data from the National Health Interview Survey (NHIS), an ongoing cross-sectional national household survey sponsored by the National Center for Health Statistics and conducted by the US Census Bureau and the Centers for Disease Control and Prevention. The purpose of the NHIS is to collect information on the health status and use of health services by the US civilian noninstitutionalized population.21 The sampling plan uses a multistage area probability design to yield nationally representative estimates. Weights are provided to adjust the sample data to reflect the age, gender, and race distribution of the US population. We examined responses for young adults who were aged 19 to 24 years and completed the NHIS for the last 4 years for which data were available (1998, 1999, 2000, and 2001). Using formulas provided by NHIS,21 we calculated a response rate of 71.7% for all adults selected for the sample adult questionnaire during the 4 years studied.
The NHIS consists of a group of surveys that collect data on households and individuals. Data are released for public use in several data files. For this study, data for each respondent were drawn from the person-level file (containing sociodemographic and basic health information for each member of a household collected directly from individuals or from other adult members of the household if the individual is not at home or is unable to answer) and from the sample adult file (containing additional health, health care utilization, and behavior data obtained from 1 randomly selected adult in each household).
Description of Variables Used
Health Care Access Variables
The dependent variables in these analyses were 4 health care access variables that categorized young adults according to whether they reported that they (1) delayed or missed health care because of cost in the previous 12 months, (2) failed to have a prescription filled because of cost in the previous 12 months, (3) had no usual source of health care, or (4) had no contact with a health professional in the previous 12 months. For these analyses, respondents were said to have a usual source of care when they reported usually going to a clinic, health center, doctor's office or health maintenance organization (HMO), hospital outpatient department, or some other place when they were sick or needed health advice. In this context, HMO refers to a staff model HMO in which providers see patients in the HMO's own facilities.22 Young adults without a usual source of health care were those who did not identify a usual source or who identified the emergency department as their usual source of care.
Health Insurance Coverage
We used survey data to identify health insurance coverage at the time of the interview. For these analyses, the uninsured were young adults who reported having no coverage through private health insurance, Medicare, Medicaid, State Children's Health Insurance Plan (SCHIP), Civilian Health and Medical Program for Uniformed Services, the Indian Health Service, or other public programs. Because of insufficient numbers for analyses, we excluded the 2.6% of male respondents who reported having Medicaid and young adults who reported having insurance coverage other than private insurance or Medicaid (1.7% of men; 2.7% of women). Also excluded were young adults for whom insurance information was missing (1.2% of men; 1.2% of women) and the few young adults who reported having both public and private insurance (0.1% of men; 0.1% of women). Young adults who reported being uninsured or having private insurance or Medicaid (women only) were included in univariate and multivariate analyses.
Sociodemographic and Health Variables
We used the survey to ascertain the young adults' highest level of educational attainment, marital status, household income, and major activity in the week before the survey. The NHIS provided recoded variations of these survey items by collapsing responses to original questionnaire items or by combining responses to >1 variable. After examining frequencies and univariate associations with the health care access variables, we further collapsed response categories to preserve adequate numbers for analyses. The young adults' highest level of educational attainment was collapsed to < 8th grade, 9th to 12th grade (no diploma), high school graduate, General Educational Development (GED) recipient, or some college (including those with or without a degree). Marital status was recoded to single (including those who were never married and those who were widowed or divorced), married (including those who were separated), and unmarried but living with a partner. Household income included income from all sources and was provided as a ratio of income to the US Census Bureau's poverty threshold for the survey year after considering overall family size and number of children in the household.23 For reference, the 2001 poverty threshold was $11 859 for a 2-person household and $17 960 for a 4-person household (2 adults, 2 children).23 Young adults were asked whether they were working at a job or business in the previous week. Those who were not working were asked why they were not working. From this information, the NHIS constructed a major activity variable that separated respondents into 4 categories: working at a job or business, going to school, keeping house, and something else. The few men who reported keeping house were included in the "something else" category. We used recoded NHIS variables to determine whether the young adult had an activity limitation attributable to a chronic medical condition.
Data Analysis
We present univariate analyses showing the relationship between insurance status and health care access variables. We found significant differences between men and women in insurance status and each of the health care access variables; therefore, all analyses were stratified by gender. We present multiple logistic regression models for each health care access (dependent) variable to assess the association between the dependent variable and insurance status while controlling for sociodemographic/health variables, yielding adjusted odds ratios (AORs) and 95% confidence intervals (CIs). When main outcomes are common in a population, as in this study, AORs may overestimate risk ratios that are >1 and underestimate risk ratios that are <1. To improve our estimation of true risk ratios, we present adjusted relative risks and 95% CIs as described by Zhang and Yu.24 Final analyses were conducted by using SUDAAN (Research Triangle Institute, Research Triangle Park, NC) to account for the complex sampling design and clustering of data in the NHIS.25
Among young adults, 21% did not provide complete income data. Compared with participants for whom income data were available, those who did not provide income data were more likely to be uninsured, be a member of a racial or ethnic minority, and have lower educational attainment. Those who did not provide income data were also more likely to report that they had not seen a provider in the previous year but were less likely to report delaying health care because of cost. Men but not women who did not provide income data were more likely to report having no usual source of health care. We analyzed regression models with and without the income variable. Both methods yielded similar results; therefore, we present final regression models including household income, race/ethnicity, highest level of educational attainment, major activity in the previous week, marital status, limitation of activity as a result of a chronic medical condition, and pregnancy (women only). The study protocol was approved by the Vanderbilt University Institutional Review Board (Nashville, TN).
RESULTS
Univariate and Bivariate Analyses
The total number of 19- to 24-year-old participants was 11 866. Half of the weighted sample were female, and approximately two thirds were white non-Hispanic (Table 1). In univariate analyses, there were significant between-gender differences in insurance status and the health care access measures (Table 2). One third of young men reported being uninsured, 62% reported being privately insured, and <3% reported coverage through Medicaid. Young women were less likely than men to report being uninsured (27% vs 33%; P < .0001) but also less likely to have private health insurance (58% vs 62%; P < .0001). Nearly 11% of women reported having coverage through Medicaid. Young women were significantly more likely than men to report delaying or missing medical care because of cost or failing to fill a prescription because of cost. Men were significantly more likely to report that they had no usual source of health care and had no contact with a health professional in the previous year.
Uninsured young adults of both genders were significantly more likely than their insured peers to report delaying or missing health care because of cost, failing to fill a prescription because of cost, having no contact with a health professional in the previous year, and having no usual source of health care (Fig 1). Young women with Medicaid did not differ significantly from privately insured women in these measures.
Multivariate Analyses
Multiple logistic regression models for each of the health care access variables studied are presented for women and men (Tables 3 and 4). Relative to insured young women, uninsured women had >3 times the adjusted risk of reporting delayed or missed medical care or failure to fill a prescription because of cost in the previous year. Uninsured women had more than twice the adjusted risk of reporting no contact with a health professional and >3 times the adjusted risk of reporting no usual source of health care relative to insured women. After adjustment, women with Medicaid did not have a higher risk of reporting any of these potential barriers relative to privately insured peers.
Findings for uninsured young men were similar to those for women. Uninsured men had 4 times higher adjusted risk of reporting delayed or missed care or failure to fill a prescription relative to privately insured men. Uninsured men had significantly higher risk of reporting having had no contact with a health professional in the previous year and having no usual source of health care.
Household income and race/ethnicity were also significantly associated with many of the reported health access variables in multivariate regression models. In general, lower household income was associated with higher adjusted risk of reporting health care access barriers for both genders. Relative to young men in the highest household income category (5 times the poverty level), men in households with income 0 to 3 times the poverty level were at significantly higher risk of reporting delayed or missed medical care because of cost, having no contact with a health provider, and having no usual source of care. Relative to women in the highest income category, women in all other income categories were at significantly higher risk of reporting delayed or missed medical care, whereas only those with an income between 2 and 3 times the poverty level were at significantly higher risk of reporting no visit in the last year, and women in households with income <2 times the poverty level were at significantly higher risk of reporting no usual source of care.
Relative to white non-Hispanic women, Hispanic women had significantly lower risk of reporting delayed or missed medical care but significantly higher risk of reporting having had no contact with a health professional in the previous year and having no usual source of health care. Among young men, race/ethnicity was significantly associated with each of the health care access variables. Relative to white men, Hispanic men had significantly lower adjusted risk of reporting delayed or missed medical care and significantly higher adjusted risk of reporting having had no contact with a health professional and having no usual source of health care. The risk of reporting delayed or missed medical care was also significantly lower for black men relative to white men.
In data not shown, young men and women who reported activity limitation as a result of a chronic medical condition had higher adjusted risk of reporting delayed or missed medical care because of cost and lower adjusted risk of reporting having no usual source of care and having had no contact with a medical provider relative to same-gender young adults without activity limitation as a result of a chronic medical condition.
DISCUSSION
Despite the perception of robust health, many young adults in this study reported health care needs for which care was delayed or foregone because the young adult was unable to afford it; this was particularly true among those who reported being uninsured. One in 4 uninsured women and 1 in 5 uninsured men in this study reported that they delayed or missed needed health care in the previous year because of cost. These numbers are particularly concerning given the high rates of uninsurance among young adults.1 Whereas some young adults who delay medical care may find that the underlying medical complaint is self-limited, others will be at risk for worsening symptoms or sequelae as a result of delayed diagnosis or treatment. For example, the young woman who delays care for symptoms caused by Chlamydia may spread the infection to other sexual partners, develop pelvic inflammatory disease, and increase her risk for having impaired fertility.26,27 Even when health care is received, uninsurance may have an impact on the young adult's ability to adhere to medical treatment. In our study, uninsured young adults were at significantly increased risk for failing to fill a prescription because of cost in the previous year.
Uninsured young adults were also significantly more likely to report that they had not had recent contact with a health professional. This may translate into fewer opportunities for uninsured young adults to receive recommended preventive screening and clinical services. Preventive health interventions including cessation counseling for tobacco and alcohol use and screening for certain sexually transmitted infections have proven efficacy among young adults, yet available data indicate that fewer than half of eligible young adults receive these interventions.28
Potentially compromising the young adult's access to health care further is the absence of a regular source of health care. More than 40% of uninsured young women and >60% of uninsured young men in our study lacked a usual source of health care. In comparison, the National Center for Health Statistics reported that 46% of all uninsured 18- to 64-year-olds in the 2000–2001 NHIS had no usual source of care.29 Depending on methods, others have reported that 16% to 40% of uninsured American adults lack a regular source of health care.17,18,20,30 These studies and others have shown that adults without a usual source of care are less likely to receive preventive services and are more likely to have fragmented care than those with a usual source of care; this is particularly true when they are concomitantly uninsured.31,32 Young adults without a usual source of care may have few options other than emergency department use for acute medical problems. This may contribute to further crowding of emergency centers and higher health care costs.33
Young women with Medicaid were not significantly more likely than privately insured women to report inability to obtain needed care, having no contact with a health provider, or having no usual source of care. This finding is particularly important given that 21% of the young women with Medicaid in this study reported that they were currently pregnant. Other studies have demonstrated that access to health care (including prenatal care) for the population with Medicaid coverage is generally better than access for those who are uninsured but not as good as for those with private health insurance.18,34–36 State-specific variability in Medicaid programs, limitations in health care providers who accept Medicaid, and difficulties obtaining or retaining Medicaid coverage are likely to make this coverage less optimal than private insurance; however, this study suggests that Medicaid has an important role in reducing access barriers for young women.
As expected, other socioeconomic factors were significantly related to health care access in this population. Predictably, lower household income was associated with increased risk of reporting barriers to health care access among young adults. Although the public may assume that only the poor experience barriers to health care access, the findings of this study suggest that young adults who live in households with incomes 2 to 3 times the poverty level are at higher risk of reporting barriers relative to young adults in the highest income level. This encompasses nearly half of the young adults in this study who provided income data. Variability in living situations, occupational or educational roles, and dependence on parents all are hallmarks of young adulthood that may affect this population's household income.37
We also found that Hispanic young adults were significantly less likely than those who are non-Hispanic white to report delayed medical care but significantly more likely to report having no contact with a health professional and having no usual source of health care. These findings are consistent with findings from a recent study by Weinick et al38 demonstrating that Hispanic (as well as black) Americans were less likely than those who are non-Hispanic white to use ambulatory services or have a usual source of health care. As in our study, these disparities persisted even after controlling for income and health insurance coverage. Other unmeasured socioeconomic factors, differences in actual or perceived health, or cultural factors may help to explain the disparities in health care use for this population. Given the considerable growth and heterogeneity of the population of Hispanic young adults in the United States, understanding disparities in health care access for this population warrants specific study. Our study suggests that eliminating disparities in health care access for Hispanic young adults will necessitate measures beyond improving health insurance coverage and reducing financial barriers.
Despite the millions affected, uninsurance among young adults has historically garnered little attention as a policy issue, largely because young adults are the least likely age segment of the population to vote and have few identified advocacy groups. Nearly 70% of eligible older adults voted in the 2000 presidential election, but only 36% of eligible young adults did so.39 Motivated in part by a desire to increase the political participation of this group, issues that are relevant to health care access for young adults, particularly uninsurance, have received more attention on Capitol Hill. The focus of this attention is groups of young adults who previously have been shown to be at higher risk of uninsurance, including poor and near-poor young adults and young adults who work in jobs that do not offer health insurance.2,4,6,7 The Medicaid/SCHIP Optional Coverage for Young Adults Act (HR 3192) was introduced in the House of Representatives by Congressman Vic Snyder (D-AR) in 2003 and would allow states to extend coverage to low-income young adults up to age 23 with an enhanced matching rate.40 A companion bill (S 1889) was subsequently introduced in the Senate.41 In 2004, the US Senate Republican Task Force on Health Care Costs and the Uninsured released a proposal to increase health insurance coverage with specific recommendation for young adults, including developing incentives for young adults to purchase lifetime, portable insurance and increasing the availability of health savings accounts.42 As part of his presidential platform, Senator John Kerry proposed to extend Medicaid and SCHIP coverage to low-income young adults. In addition, both Senator Kerry and President George W. Bush advanced campaign proposals that included provisions to facilitate the purchase of health insurance coverage for employees of small businesses, many of whom are young adults. These activities on behalf of young adults are promising but have yet to result in actual policy change. As noted earlier, improving insurance coverage for young adults may facilitate access to health care; however, more will need to be done to eliminate disparities in health care access for certain young adult populations.
Within the health care sector, there are also relatively few organized proponents for young adults. Young adults may receive health care from providers who specialize in pediatric, family, adult, emergency, and women's health care but are unlikely to constitute a substantial proportion of the patient population of any of these health care groups. Organized efforts of health care providers are necessary to increase public awareness of the high rates of uninsurance and barriers to health care access for young adults. Individually, health care providers may have opportunities to assist young adult patients in obtaining or retaining health insurance coverage. Potential interventions include providing anticipatory guidance to older adolescents and their parents regarding future plans for health insurance coverage, discussing the importance of health insurance coverage with young adult patients, and helping young adults locate available resources. In addition, health care providers should be mindful that opportunities to provide preventive services for young adults may be scarce. For some, an office visit for an acute medical complaint may be the only opportunity that the provider has to screen for other conditions or behaviors that place the young adult's health at risk.
Our study has several limitations. The NHIS is based on self-report or the report of other members of the household and may be subject to recall error. We calculated that 28% of those selected as sample adults did not complete the survey, and this nonresponse may contribute bias. We were unable to validate insurance status through another source, and measures of health insurance adequacy or inquiries about gaps in insurance coverage among the currently insured were not included. Finally, the cross-sectional nature of this study does not allow us to determine that lack of health insurance caused the reported health access barriers or to determine the immediate or long-term health outcomes resulting from the reported delayed or foregone care.
CONCLUSIONS
The findings from this study demonstrate that 19- to 24-year-olds who lack health insurance face significant barriers to obtaining health care when they need it. Even after sociodemographic and health characteristics were adjusted for, uninsured young adults were significantly more likely than the privately insured to report being unable to obtain needed care, having no contact with a health professional in the previous year, and having no usual source of health care. Given the high rates of uninsurance among young adults, additional study is needed to examine how these barriers affect the immediate and future health of the young adult.
FOOTNOTES
Accepted Oct 14, 2004.
No conflict of interest declared.
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