Drug coverage and drug purchases by medicare beneficiaries with hypertension

Health Affairs

Volumn 19, Issue 2, 2000, Pages 219-230

  Blustein, Jan ^a  

^a NEW YORK UNIVERSITY   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

ANTIHYPERTENSIVE AGENT;

AGED; ARTICLE; ECONOMICS; EPIDEMIOLOGY; FEMALE; FINANCIAL MANAGEMENT; HEALTH CARE DELIVERY; HEALTH CARE POLICY; HUMAN; INSURANCE; LONGITUDINAL STUDY; MALE; MEDICARE; NEEDS ASSESSMENT; PRESCRIPTION; UNITED STATES;

AGED; AGED, 80 AND OVER; ANTIHYPERTENSIVE AGENTS; FEMALE; FINANCING, PERSONAL; HEALTH CARE SURVEYS; HEALTH POLICY; HEALTH SERVICES ACCESSIBILITY; HUMANS; INSURANCE COVERAGE; LONGITUDINAL STUDIES; MALE; MEDICARE; NEEDS ASSESSMENT; PRESCRIPTIONS, DRUG; UNITED STATES;

EID: 0034145335     PISSN: 02782715     EISSN: None     Source Type: Journal    
DOI: 10.1377/hlthaff.19.2.219     Document Type: Article

References (27)

1. National Bipartisan Commission on the Future of Medicare, "Private Supplemental Insurance Coverage Summary," medicare.commission.gov/medicare/K-P-1499.html (4 January 1999).
2. L. Lagnado, "Drug Costs Can Leave Elderly a Grim Choice: Pills or Other Needs,"Wall Street Journal, 11 November 1998, A1.
3. American Heart Association, "Report of the Task Force on the Availability of Cardiovascular Drugs to the Medically Indigent," Circulation 85, no. 2 (1992): 849-860.
4. S.B. Soumerai et al., "Payment Restrictions for Prescription Drugs under Medicaid: Effects on Therapy, Cost, and Equity," New England Journal of Medicine 317, no. 9 (1987): 550-556; and S.B. Soumerai et al., "Effects of Medicaid Drug-Payment Limits on Admission to Hospitals and Nursing Homes," New England Journal of Medicine 325, no. 15 (1991): 1072-1077.
5. S.B. Soumerai et al., "Payment Restrictions for Prescription Drugs under Medicaid: Effects on Therapy, Cost, and Equity," New England Journal of Medicine 317, no. 9 (1987): 550-556; and S.B. Soumerai et al., "Effects of Medicaid Drug-Payment Limits on Admission to Hospitals and Nursing Homes," New England Journal of Medicine 325, no. 15 (1991): 1072-1077.
6. M. Davis et al., "Prescription Drug Coverage, Utilization, and Spending among Medicare Beneficiaries," Health Affairs (Jan/Feb 1999): 231-243. Also, see J. Rogowski, LA. Lillard, and R. Kington, "The Financial Burden of Prescription Drug Use among Elderly Persons," Gerontologist 37, no. 4 (1997): 475-482.
7. M. Davis et al., "Prescription Drug Coverage, Utilization, and Spending among Medicare Beneficiaries," Health Affairs (Jan/Feb 1999): 231-243. Also, see J. Rogowski, LA. Lillard, and R. Kington, "The Financial Burden of Prescription Drug Use among Elderly Persons," Gerontologist 37, no. 4 (1997): 475-482.
8. A notable exception is a study by Bruce Stuart and James Grana, which examines the link between drug coverage and the likelihood of using prescription drugs in the general elderly Medicare population. B. Stuart and J. Grana, "Ability to Pay and the Decision to Medicate," Medical Care 36, no. 2 (1998): 202-211. Based on treatment of twenty-three conditions, the study finds that drug coverage increases utilization and shows that this is generally more pronounced for more serious conditions. However, a lack of clinical detail, as well as relatively small sample sizes for many of the conditions, make interpretation of the findings somewhat problematic.
9. National Heart, Lung, and Blood Institute, The Sixth Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure, NIH Pub. no. 98-4080 (Bethesda, Md.: National Institutes of Health, November 1997).
10. "MCBS Survey Overview," www.hcfa.gov/mcbs/overview.asp (November 1998).
11. Persons who died during the year were excluded because they would not be expected to have a full year's medication use. Those who did not have Part B coverage were excluded because they may have had atypical access to physician services, and hence unusual drug prescribing patterns.
12. Some persons may have been unaware that they had hypertension. Since prior studies have shown that using the International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) codes on Medicare billing data can enrich the pool of subjects correctly identified as having hypertension, we also searched all inpatient and outpatient Medicare bills for the year for the relevant codes. This yielded 512 additional subjects. However, since health maintenance organizations (HMOs) do not submit bills to Medicare, our HMO participants did not have bills to search, and so the HMO subsample could not be enriched in this fashion. Because the impact of HMO participation was one of the questions addressed in the analyses, and because we wanted to avoid using different criteria in identifying subjects with hypertension in the HMO and non-HMO subsamples, we elected not to use billing data to enrich our sample of 4,334 subjects. Confirmatory analyses on the enriched sample, excluding HMO participants, yielded results that were essentially unchanged from those reported here.
13. Physician's Desk Reference, 51st ed. (Montvale, N.J.: Medical Economics Publishers, 1997); and Drug Facts and Comparisons (St. Louis: Walters Kluwer, 1997).
14. Physician's Desk Reference, 51st ed. (Montvale, N.J.: Medical Economics Publishers, 1997); and Drug Facts and Comparisons (St. Louis: Walters Kluwer, 1997).
15. Since some subjects had multiple forms of supplemental insurance, the algorithm used to place them in only one class was as follows: Subjects reporting that they had self-purchased or employer-sponsored insurance were placed in those classes; those with both forms were placed in the employer-sponsored class. Of those remaining, those who were listed as full-year or part-year HMO enrollees in Health Care Financing Administration (HCFA) administrative records were placed in the HMO class. Of those remaining, those who reported having Medicaid insurance or were listed as having Medicaid insurance in HCFA administrative files were classified in the Medicaid group. Those still remaining were classified as having no supplemental insurance.
16. Similar criteria for assigning drug coverage status were used in Davis et al., "Prescription Drug Coverage."
17. Guidelines issued in 1996, which reflect prices during the 1995 calendar year, are $7,740 for a person age sixty-five or older, living alone, and $10,360 for a couple age sixty-five and older, living in a household. "The 1996 HHS Poverty Guideline," aspe.hhs.gov/poverty/96poverty.htm (1996).
18. Codes 99201 through 99295 identified office visits. Since such bills are not routinely available for HMOs, HMO enrollees were assigned the non-HMO sample mean number of physician visits in multivariate analyses.
19. To normalize the distribution on the dependent variable, models for Outcome 2 were trimmed to eliminate cases with values in the top 5 percent of the dependent variable. Models using a log-transformed dependent variable also were run and yielded similar results to those reported here. Since the coefficients of the nontransformed model are more readily interpretable, they are presented. All analyses reported incorporate observational weights reflecting the MCBS sampling methodology and nonresponse propensity; SUDAAN software was used to take into account the design effect potentially resulting from cluster sampling. Multivariate models underwent standard tests of colinearity and performed favorably. For tests of the hypothesis that drug coverage translates into an increased likelihood of purchasing medications, one-tailed tests were used. All other hypothesis testing was two-tailed.
20. Prices of particular antihypertensive drugs vary widely according to manufacturer, distributor, health plan, and vendor. Moreover, for the same drug, prices vary according to medication strength. Still, it is generally the case that diuretics and beta-blockers are less costly than calcium channel blockers and ACE inhibitors. See NHLBI, The Sixth Report.
21. Full multivariate results are available upon request from the author at Wagner Graduate School, New York University, 4 Washington Square North, New York, New York 10012.
22. L.A. Lillard, J. Rogowski, and R. Kington, "Insurance Coverage for Prescription Drugs: Effects on Use and Expenditures in the Medicare Population" (Working paper, RAND, 1997); and Stuart and Grana, "Ability to Pay."
23. L.A. Lillard, J. Rogowski, and R. Kington, "Insurance Coverage for Prescription Drugs: Effects on Use and Expenditures in the Medicare Population" (Working paper, RAND, 1997); and Stuart and Grana, "Ability to Pay."
24. M. Berk, C. Schur, and P. Mohr, "Using Survey Data to Estimate Prescription Drug Costs," Health Affairs (Fall 1990): 146-156; and Office of Strategic Planning, Health Care Financing Administration, "MCBS Prescription Drug Underreporting" (Internal memorandum, May 1999).
25. M. Berk, C. Schur, and P. Mohr, "Using Survey Data to Estimate Prescription Drug Costs," Health Affairs (Fall 1990): 146-156; and Office of Strategic Planning, Health Care Financing Administration, "MCBS Prescription Drug Underreporting" (Internal memorandum, May 1999).
26. For instance, to the extent that some drugs were prescribed to be taken more than once, our analyses overestimate the adequacy of number of tablets purchased. Also, our multivariate analyses implicitly assumed that subjects taking two different types of antihypertensives were taking those drugs concurrently. For subjects for whom this was not the case (for example, those who switched drug type in midyear), our assumption resulted in an underestimate. Finally, some subjects may have controlled their hypertension through diet, exercise, and related behavior, not antihypertensive medication. We have no reason to believe that this or any of the above limitations apply disproportionately to any particular group; however, to the extent that this belief is incorrect, the impact estimates reported here may be biased.
27. D.J. Gross et al., "Out-of-Pocket Health Spending by Poor and Near-Poor Elderly Medicare Beneficiaries," Health Services Research 34, no. 1 (1999): 241-254.