© 2002 American Public Health Association
At the time of this study, Jae Kennedy was with the Department of Community Health, University of Illinois at UrbanaChampaign. Christopher Erb is with the Medical Scholars Program, University of Illinois at UrbanaChampaign. Correspondence: Jae Kennedy, PhD, Department of Health Policy and Administration, Washington State University at Spokane, 310 N Riverpoint Blvd, Box H, Spokane, WA 99202-1675 (e-mail: jjkenned{at}mail.wsu.edu).
Objectives. This study estimated national prevalence rates of medication noncompliance due to cost and resulting health problems among adults with disabilities. Methods. Analyses involved 25 805 respondents to the Disability Follow-Back Survey, a supplement to the 1994 and 1995 National Health Interview Surveys. Results. Findings showed that about 1.3 million adults with disabilities did not take their medications as prescribed because of cost, and more than half reported health problems as a result. Severe disability, poor health, low income, lack of insurance, and a high number of prescriptions increased the odds of being noncompliant as a result of cost. Conclusions. Prescription noncompliance due to cost is a serious problem for many adults with chronic disease or disability. Most would not be helped by any of the current proposals to expand Medicare drug coverage.
Medicare prescription drug insurance is a recurrent focus of American health policy,1 and a combination of rapidly escalating drug costs2 and insurance industry trends3,4 have again thrust the issue to center stage. One of the more compelling rationales offered for expanding drug coverage is that affordability problems have clinical as well as economic consequences; that is, patients who have difficulty paying for medications are less likely to take them and can suffer adverse health effects as a result of noncompliance.5,6 Although this argument has intuitive appeal, no national data are available on cost-associated noncompliance, leading commentators to question both the scope of affordability problems and the remedies proposed to address them.7 In the present study, we sought to illuminate a critical aspect of the policy debate by developing the first national prevalence estimates of prescription noncompliance due to cost and resulting health problems among adults with disabilities, a population known to be heavy users of health care,8,9 including prescription drugs.911 Medicare recipients with drug coverage are more likely to fill their prescriptions than those without coverage.1214 Total and out-of-pocket drug costs are heavily skewed toward individuals with poor health or chronic conditions, even among recipients with drug coverage.15 Noncompliance with prescription regimens is a widely recognized clinical problem,16 particularly in the case of treatment of chronic illnesses such as hypertension,17 and it has been identified as an important predictor of emergency room visits18 and hospital admissions.19,20 Numerous studies have linked rates of noncompliance to (1) sociodemographic factors, including age,2123 sex,17 and race/ethnicity24; (2) socioeconomic factors, including insurance coverage25 and out-of-pocket costs18,19; and (3) treatment factors, including type26 and number of drugs prescribed27 and complexity of drug regimen.21 We examined the relative influences of these factors on self-reported noncompliance due to cost.
Data Source The Disability Supplement and the Disability Follow-Back Survey (DFS) are special supplements to the National Health Interview Survey (NHIS), a continuing probability survey of households representative of the civilian noninstitutionalized population of the United States.28 The Disability Supplement was administered to all respondents at the same time they completed the 1994 and 1995 NHIS core surveys. The DFS was administered 6 to 18 months later to respondents who reported impairments, functional limitations, chronic conditions, or receipt of disability benefits in the core NHIS surveys or the Disability Supplement.29 We used data from the adult supplement, which was administered to 25 805 respondents 18 years or older with disabilities (about 17% of the NHIS sample). Adults selected for the DFS differed from the general population selected for the NHIS in predictable ways. They were older (according to weighted estimates, 35% of DFS adult respondents were 65 years or older, compared with 13% of NHIS adult respondents), had lower incomes (19% of DFS respondents had incomes at or below the poverty level, compared with 12% of NHIS respondents), and were in worse health (69% of DFS adult respondents rated their health as fair or poor, compared with 34% of NHIS respondents).
Data Analysis
Almost 70% of the disabled adult populationabout 28 million peoplereported having been prescribed 1 or more medications (Table 1
Table 3
Individuals who described their health as fair or poor were more likely to be noncompliant than were those who rated their health as good, very good, or excellent (OR = 1.4; 95% CI = 1.1, 1.7). The relationship between severity of disability and cost-associated noncompliance appeared to be curvilinear, with the highest level of noncompliance among moderately impaired adults who were limited in, but did not require assistance with, 1 or more activities of daily living (OR = 1.9; 95% CI = 1.5, 2.5). Disabled adults who were prescribed 3 or more medications were more likely than those who were prescribed 1 or 2 medications to report cost-associated noncompliance (35 medications: OR = 1.4; 95% CI = 1.1, 1.7; 6 or more medications: OR = 1.6; 95% CI = 1.2, 2.1). Sex and race/ethnicity appeared to be only modestly related to cost-associated noncompliance, but there was a strong negative relationship between age and noncompliance: younger adults (those aged 1834 years) were nearly 10 times more likely to be noncompliant as a result of cost than were members of the oldest cohort (those 75 years or older; OR = 0.1; 95% CI = 0.1, 0.2). However, members of younger cohorts were also less likely to be prescribed medications.
To clarify this relationship, we plotted the number of adults with prescriptions and the proportions reporting cost-associated noncompliance according to age group. Figure 1
All noncompliant respondents were asked whether they had experienced any adverse health consequences (Table 4
Our study showed that about 1.3 million adults with disabilities reported that the cost of the medicine(s) they were prescribed was so high that they could not afford to fill or refill their prescriptions or to take their medication as prescribed. More than half of this group identified 1 or more potentially serious and costly health problems that they attributed to noncompliance. These prevalence figures are impressive; for several reasons, however, they probably underestimate the true scope of drug affordability problems among people with disabilities. First, our data did not allow us to estimate the number of people who take their medications as prescribed but do so at great personal cost. For some people with disabilities or chronic illnesses, limited incomes force a monthly choice between medication and food.31 Second, although only recently released to the research community, the surveys we examined are somewhat dated. Drug costs have skyrocketed in the period since the data were collected,2 potentially threatening the health and economic security of many more adults with and without disabilities.6,32,33 Third, all compliance data were self-reported and thus subject to biases associated with such survey methods.34 Indeed, underreporting of noncompliance is such a widely recognized problem26 that many researchers use independent verification strategies such as pill counts35 and electronic monitoring.36 Despite these limitations, our analysis raises some provocative research and policy questions. As might be expected, income and insurance status were strong predictors of noncompliance due to cost. The magnitude of the insurance differences, however, was striking; after other risk factors had been controlled, disabled adults without insurance were nearly 4 times more likely than those with private insurance to report medication noncompliance due to cost. The finding that people who were in poorer health or who took more medications were also at higher risk of cost-associated noncompliance was consistent with previous research. However, the curvilinear relationship found between severity of disability and noncompliance due to cost merits further investigation. The relatively lower rate of noncompliance among Hispanic adults with disabilities was unanticipated, and additional research is clearly needed to verify this relationship. Our most remarkable finding from a public policy perspective was that cost-associated noncompliance was concentrated primarily in younger cohorts. This result seems to contradict much of the recent political commentary on drug affordability, although other studies have also revealed a negative relationship between age and compliance.21,22 Additional research is needed, however, before we would concur with the conclusion of Park et al. that, in terms of medication compliance, "older is wiser."23 Indeed, at least for the population of adults with disabilities, the more appropriate adage might be "younger is poorer" (or, at least, "younger is less likely to be insured"). Most of the 1.3 million disabled adults identified in this study would not be helped by any of the current proposals to expand Medicare drug coverage, because only 27% received Medicare. If this population were included in the policy debate and ways were found to increase prescription drug coverage for all adults with chronic illnesses and disabilities, much of the exacerbation of symptoms and conditions found in this studyand many of the associated health care expenditurescould be avoided.
Preparation of this article was supported in part by a fellowship from the National Institute of Disability and Rehabilitation Research (grant H133F990001) and by a grant from the Mary Jane Neer Fund at the University of Illinois. The Disability Follow-Back Survey adult data were provided by the National Center for Health Statistics, and prevalence data on prescription drug use among adults with disabilities were first presented by John Hough (of the Division of Birth Defects, Child Development, Disability and Health, Centers for Disease Control and Prevention) at the 1999 Annual Meeting of the American Public Health Association.
Note. The analyses, interpretations, and conclusions are those of the authors and do not necessarily reflect the views of the National Center for Health Statistics, the National Institute of Disability and Rehabilitation Research, Washington State University, or the University of Illinois. J. Kennedy designed the study, conducted the analyses, and wrote the article. C. Erb conducted the literature review, collaborated in analysis design and interpretation, and contributed to the writing of the article. Accepted for publication June 7, 2001.
1. Long SH. Prescription drugs and the elderly: issues and options. Health Aff.1994;13(2):157174.[Abstract] 2. Hard to Swallow: Rising Prices for America's Seniors. Washington, DC: Families USA; 1999. 3. Moran DW. Prescription drugs and managed care: can free-market detente hold? Health Aff.2000;19(2):6377.[Abstract] 4. McClellan M, Spatz ID, Carney S. Designing a Medicare prescription drug benefit: issues, obstacles, and opportunities. Health Aff.2000;19(2):2641.[Abstract] 5. Disturbing Truths and Dangerous Trends: The Facts About Medicare Beneficiaries and Prescription Drug Coverage. Washington, DC: National Economic Council; 1999.
6.
Soumerai SB, Ross-Degnan D. Inadequate prescription-drug coverage for Medicare enrolleesa call to action. N Engl J Med.1999;340:722728. 7. Frogue J. How to Provide Prescription Drug Coverage Under Medicare. Washington, DC: Heritage Foundation; 1999. 8. Chrischilles EA, Foley DJ, Wallace RB, et al. Use of medications by persons 65 and over: data from the established populations for epidemiologic studies of the elderly. J Gerontol.1992;47:M137M144.[Abstract] 9. LaPlante MP, Rice DP, Wenger BL. Medical Care Use, Health Insurance, and Disability in the United States. Washington, DC: National Institute of Disability and Rehabilitation Research; 1995. 10. Max W, Rice DP, Trupin L. Medical Expenditures for People With Disabilities. Washington, DC: National Institute of Disability and Rehabilitation Research; 1995.
11.
Mueller C, Schur C, O'Connell J. Prescription drug spending: the impact of age and chronic disease status. Am J Public Health.1997;87:16261629. 12. Davis M, Poisal J, Chulis G, Zarabozo C, Cooper B. Prescription drug coverage, utilization, and spending among Medicare beneficiaries. Health Aff.1999;18(1):231243.[Abstract] 13. Poisal JA, Murray LA, Chulis GS, Cooper BS. Prescription drug coverage and spending for Medicare beneficiaries. Health Care Financ Rev.1999;20(3):1527.[Medline] 14. Stuart B, Grana J. Ability to pay and the decision to medicate. Med Care.1998;36:202211.[Medline] 15. Steinberg EP, Gutierrez B, Momani A, Boscarino JA, Neuman P, Deverka P. Beyond survey data: a claims-based analysis of drug use and spending by the elderly. Health Aff.2000;19(2):198211.[Abstract] 16. Sackett DL, Haynes RB, eds. Compliance With Therapeutic Regimens. Baltimore, Md: Johns Hopkins University Press; 1976. 17. Costa FV. Compliance with antihypertensive treatment. Clin Exp Hypertens.1996;18:463472. 18. Olshaker JS, Barish RA, Naradzay JF, Jerrard DA, Safir E, Campbell L. Prescription noncompliance: contribution to emergency department visits and cost. J Emerg Med.1999;17:909912.[Medline]
19.
Col N, Fanale JE, Kronholm P. The role of medication noncompliance and adverse drug reactions in hospitalizations of the elderly. Arch Intern Med.1990;150:841845. 20. Maronde RF, Chan LS, Larsen FJ, Strandberg LR, Laventurier MF, Sullivan SR. Underutilization of antihypertensive drugs and associated hospitalization. Med Care.1989;27:11591166.[Medline] 21. Bailey JE, Lee MD, Somes GW, Graham RL. Risk factors for antihypertensive medication refill failure by patients under Medicaid managed care. Clin Ther.1996;18:12521262.[Medline] 22. Faulkner DL, Young C, Hutchins D, McCollam JS. Patient noncompliance with hormone replacement therapy: a nationwide estimate using a large prescription claims database. Menopause.1998;5:226229.[Medline] 23. Park DC, Hertzog C, Leventhal H, et al. Medication adherence in rheumatoid arthritis patients: older is wiser. J Am Geriatr Soc.1999;47:172183.[Medline]
24.
Monane M, Bohn RL, Gurwitz JH, Glynn RJ, Levin R, Avorn J. Compliance with antihypertensive therapy among elderly Medicaid enrollees: the roles of age, gender, and race. Am J Public Health.1996;86:18051808.
25.
Bazargan M, Barbre AR, Hamm V. Failure to have prescriptions filled among black elderly. J Aging Health.1993;5:264282. 26. McElnay JC, McCallion CR, al-Deagi F, Scott M. Self-reported medication non-compliance in the elderly. Eur J Clin Pharmacol.1997;53:171178.[Medline] 27. Botelho RJ, Dudrak RD. Home assessment of adherence to long-term medication in the elderly. J Fam Pract.1992;35:6165.[Medline] 28. Massey JT, Moore TF, Parsons VL, Tadros W. Design and estimation for the National Health Survey, 198594. Vital Health Stat 2. 1989;No. 110. 29. Data File Documentation, National Health Interview Survey on Disability, Phase 1 and Phase 2, 1994. Hyattsville, Md: National Center for Health Statistics; 1998. CD-ROM series 10, No. 9. 30. Software for the Statistical Analysis of Correlated Data (SUDAAN), Version 7.5. Research Triangle Park, NC: Research Triangle Institute; 1998. 31. Chubon SJ, Schulz RM, Lingle EW Jr, Coster-Schulz MA. Too many medications, too little money: how do patients cope? Public Health Nurs.1994;11:412415.[Medline] 32. Thornton D. By the numbers: the rising costs of prescription drugs. Healthplan.1999;40(5):7172.[Medline] 33. Rogowski J, Lillard LA, Kington R. The financial burden of prescription drug use among elderly persons. Gerontologist.1997;37:475482.[Abstract] 34. Babbie E, Wagenaar T. Practicing Social Research. 3rd ed. Belmont, Calif: Wadsworth Publishing Co; 1983. 35. Larrat EP, Taubman AH, Willey C. Compliance-related problems in the ambulatory population. Am Pharmacy.1990;30(2):1823. 36. Park DC, Morrell RW, Frieske D, Kincaid D. Medication adherence behaviors in older adults: effects of external cognitive supports. Psychol Aging.1992;7:252256.[Medline] This article has been cited by other articles:
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