Skip to main content
PMC home page
Health Services Research logoLink to Health Services Research
. 1995 Oct;30(4):593–614.

The diffusion of innovation in AIDS treatment: zidovudine use in two New Jersey cohorts.

S Crystal 1, U Sambamoorthi 1, C Merzel 1
PMCID: PMC1070077  PMID: 7591783

Abstract

OBJECTIVE. This study investigates patterns of utilization of zidovudine (ZDV) by gender, race, risk group, and other respondent characteristics following approval of this treatment. STUDY POPULATION. Longitudinal observational data were used on a demographically diverse population participating in New Jersey's Medicaid waiver program for persons with symptomatic HIV disease. DATA EXTRACTION METHODS. Claims data were merged with administrative data on demographic characteristics, risk group, and functional status. Periods of ZDV utilization were determined by analysis of pharmacy claims. DESIGN. The proportion of respondents ever using ZDV (treatment incidence) and the proportion of time on ZDV among users (treatment persistence) were analyzed for a cohort enrolling in 1987 and 1988, and for a cohort enrolling in 1989 and 1990, with follow-up of utilization through August 1992. For each cohort, bivariate analyses were used to compare incidence and persistence by patient subgroup; logistic regression was used to investigate the predictors of incidence in a multivariate model; and OLS regression was used to analyze proportion of time on ZDV among those with any ZDV use. PRINCIPAL FINDINGS. For the 1987-1988 cohort, substantial race, gender, and risk group differences in utilization were observed, even though all participants in this Medicaid population had financial coverage for ZDV treatment. Treatment incidence was significantly lower for blacks than for others in bivariate comparison (45 percent versus 63 percent had any use of ZDV) and in a logistic regression controlling for a variety of demographic and health status indicators (relative risk .46, CI .31 a variety of demographic and health status indicators (relative risk .46, CI .31 to .69). Treatment persistence differences were also substantial in the 1987-1988 cohort: among ZDV users, women, blacks, and injection drug users (IDUs) had significantly less persistence in use, and the gender and risk group differences were significantly in a multivariate model. In the 1989-1990 cohort, however, both incidence and persistence of treatment converged: no significant differences were observed across demographic groups. CONCLUSIONS. Less-advantaged subgroups lagged in access to this new therapy, suggesting the presence of nonfinancial barriers to care. However, these initial differences subsequently converged. RELEVANCE/IMPACT. Socioeconomic differences have been observed in access to newly introduced treatments for a variety of diseases, reflecting nonfinancial as well as financial barriers to care. Such differences may or may not disappear as use of therapies becomes institutionalized. Monitoring patterns of treatment initiation as well as persistence of treatment over time, using merged data from claims and administrative files, can provide important information on the diffusion of treatments and the extent to which initial disparities are or are not reduced over time.

Full text

PDF

Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Andrulis D. P., Weslowski V. B., Gage L. S. The 1987 US hospital AIDS survey. JAMA. 1989 Aug 11;262(6):784–794. [PubMed] [Google Scholar]
  2. Bennett C. L., Adams J., Gertler P., Park R. E., Gilman S., George L., Shapiro M., Brook R. H. Relation between hospital experience and in-hospital mortality for patients with AIDS-related Pneumocystis carinii pneumonia: experience from 3,126 cases in New York City in 1987. J Acquir Immune Defic Syndr. 1992;5(9):856–864. [PubMed] [Google Scholar]
  3. Boutwell R. C., Mitchell J. B. Diffusion of new technologies in the treatment of the Medicare population. Implications for patient access and program expenditures. Int J Technol Assess Health Care. 1993 Winter;9(1):62–75. doi: 10.1017/s0266462300003032. [DOI] [PubMed] [Google Scholar]
  4. Broder S., Mitsuya H., Yarchoan R., Pavlakis G. N. NIH conference. Antiretroviral therapy in AIDS. Ann Intern Med. 1990 Oct 15;113(8):604–618. doi: 10.7326/0003-4819-113-8-604. [DOI] [PubMed] [Google Scholar]
  5. Brudney K. Homelessness and TB: a study in failure. J Law Med Ethics. 1993 Fall-Winter;21(3-4):360–367. doi: 10.1111/j.1748-720x.1993.tb01261.x. [DOI] [PubMed] [Google Scholar]
  6. Cantor J. C. Health care unreform. The New Jersey approach. JAMA. 1993 Dec 22;270(24):2968–2970. [PubMed] [Google Scholar]
  7. Coye M. J., Grant C., Hummel R. P., Conviser R. A statewide early intervention program for HIV-infected people. Am J Public Health. 1992 Feb;82(2):303–304. [PubMed] [Google Scholar]
  8. Dunn D. L., Chen M. Uncompensated hospital care payment and access for the uninsured: evidence from New Jersey. Health Serv Res. 1994 Apr;29(1):113–130. [PMC free article] [PubMed] [Google Scholar]
  9. Easterbrook P. J., Keruly J. C., Creagh-Kirk T., Richman D. D., Chaisson R. E., Moore R. D. Racial and ethnic differences in outcome in zidovudine-treated patients with advanced HIV disease. Zidovudine Epidemiology Study Group. JAMA. 1991 Nov 20;266(19):2713–2718. [PubMed] [Google Scholar]
  10. Fahs M. C., Fulop G., Strain J., Sacks H. S., Muller C., Cleary P. D., Schmeidler J., Turner B. The inpatient AIDS unit: a preliminary empirical investigation of access, economic, and outcome issues. Am J Public Health. 1992 Apr;82(4):576–578. doi: 10.2105/ajph.82.4.576. [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. Fischl M. A., Richman D. D., Grieco M. H., Gottlieb M. S., Volberding P. A., Laskin O. L., Leedom J. M., Groopman J. E., Mildvan D., Schooley R. T. The efficacy of azidothymidine (AZT) in the treatment of patients with AIDS and AIDS-related complex. A double-blind, placebo-controlled trial. N Engl J Med. 1987 Jul 23;317(4):185–191. doi: 10.1056/NEJM198707233170401. [DOI] [PubMed] [Google Scholar]
  12. Gaston R. S., Ayres I., Dooley L. G., Diethelm A. G. Racial equity in renal transplantation. The disparate impact of HLA-based allocation. JAMA. 1993 Sep 15;270(11):1352–1356. [PubMed] [Google Scholar]
  13. Gibaldi M. Ethnic differences in the assessment and treatment of disease. Pharmacotherapy. 1993 May-Jun;13(3):170–176. [PubMed] [Google Scholar]
  14. Goldberg K. C., Hartz A. J., Jacobsen S. J., Krakauer H., Rimm A. A. Racial and community factors influencing coronary artery bypass graft surgery rates for all 1986 Medicare patients. JAMA. 1992 Mar 18;267(11):1473–1477. [PubMed] [Google Scholar]
  15. Goldsmith M. F. Specific HIV-related problems of women gain more attention at a price--affecting more women. JAMA. 1992 Oct 14;268(14):1814–1816. [PubMed] [Google Scholar]
  16. Hannan E. L., Kilburn H., Jr, O'Donnell J. F., Lukacik G., Shields E. P. Interracial access to selected cardiac procedures for patients hospitalized with coronary artery disease in New York State. Med Care. 1991 May;29(5):430–441. doi: 10.1097/00005650-199105000-00004. [DOI] [PubMed] [Google Scholar]
  17. Hirsch M. S., D'Aquila R. T. Therapy for human immunodeficiency virus infection. N Engl J Med. 1993 Jun 10;328(23):1686–1695. doi: 10.1056/NEJM199306103282307. [DOI] [PubMed] [Google Scholar]
  18. Markson L. E., Cosler L. E., Turner B. J. Implications of generalists' slow adoption of zidovudine in clinical practice. Arch Intern Med. 1994 Jul 11;154(13):1497–1504. [PubMed] [Google Scholar]
  19. McBean A. M., Gornick M. Differences by race in the rates of procedures performed in hospitals for Medicare beneficiaries. Health Care Financ Rev. 1994 Summer;15(4):77–90. [PMC free article] [PubMed] [Google Scholar]
  20. Merzel C., Crystal S., Sambamoorthi U., Karus D., Kurland C. New Jersey's Medicaid waiver for acquired immunodeficiency syndrome. Health Care Financ Rev. 1992 Spring;13(3):27–44. [PMC free article] [PubMed] [Google Scholar]
  21. Moore R. D., Hidalgo J., Sugland B. W., Chaisson R. E. Zidovudine and the natural history of the acquired immunodeficiency syndrome. N Engl J Med. 1991 May 16;324(20):1412–1416. doi: 10.1056/NEJM199105163242006. [DOI] [PubMed] [Google Scholar]
  22. Moore R. D., Stanton D., Gopalan R., Chaisson R. E. Racial differences in the use of drug therapy for HIV disease in an urban community. N Engl J Med. 1994 Mar 17;330(11):763–768. doi: 10.1056/NEJM199403173301107. [DOI] [PubMed] [Google Scholar]
  23. Petronis K. R., Carroll C. E., Held P. J., Port F. K. Effect of race on access to recombinant human erythropoietin in long-term hemodialysis patients. JAMA. 1994 Jun 8;271(22):1760–1763. [PubMed] [Google Scholar]
  24. Phelps C. E. Diffusion of information in medical care. J Econ Perspect. 1992 Summer;6(3):23–42. doi: 10.1257/jep.6.3.23. [DOI] [PubMed] [Google Scholar]
  25. Powe N. R., Griffiths R. I., de Lissovoy G., Anderson G. F., Watson A. J., Greer J. W., Herbert R. J., Eggers P. W., Milam R. A., Whelton P. K. Access to recombinant erythropoietin by Medicare-entitled dialysis patients in the first year after FDA approval. JAMA. 1992 Sep 16;268(11):1434–1440. [PubMed] [Google Scholar]
  26. Richman D. D., Fischl M. A., Grieco M. H., Gottlieb M. S., Volberding P. A., Laskin O. L., Leedom J. M., Groopman J. E., Mildvan D., Hirsch M. S. The toxicity of azidothymidine (AZT) in the treatment of patients with AIDS and AIDS-related complex. A double-blind, placebo-controlled trial. N Engl J Med. 1987 Jul 23;317(4):192–197. doi: 10.1056/NEJM198707233170402. [DOI] [PubMed] [Google Scholar]
  27. Rosenberg P. S., Gail M. H., Schrager L. K., Vermund S. H., Creagh-Kirk T., Andrews E. B., Winkelstein W., Jr, Marmor M., Des Jarlais D. C., Biggar R. J. National AIDS incidence trends and the extent of zidovudine therapy in selected demographic and transmission groups. J Acquir Immune Defic Syndr. 1991;4(4):392–401. [PubMed] [Google Scholar]
  28. Sandrick K. Learning from experience. In AIDS treatment, knowledge means quality. Hospitals. 1993 Apr 5;67(7):32–35. [PubMed] [Google Scholar]
  29. Stein M. D., Piette J., Mor V., Wachtel T. J., Fleishman J., Mayer K. H., Carpenter C. C. Differences in access to zidovudine (AZT) among symptomatic HIV-infected persons. J Gen Intern Med. 1991 Jan-Feb;6(1):35–40. doi: 10.1007/BF02599388. [DOI] [PubMed] [Google Scholar]
  30. Whittle J., Conigliaro J., Good C. B., Lofgren R. P. Racial differences in the use of invasive cardiovascular procedures in the Department of Veterans Affairs medical system. N Engl J Med. 1993 Aug 26;329(9):621–627. doi: 10.1056/NEJM199308263290907. [DOI] [PubMed] [Google Scholar]
  31. Yedidia M. J. The impact of social factors on the content of care. Treatment of ischemic heart disease at a public and a voluntary hospital. Arch Intern Med. 1992 Mar;152(3):595–600. [PubMed] [Google Scholar]

Articles from Health Services Research are provided here courtesy of Health Research & Educational Trust

RESOURCES