Antiretroviral use and pharmacy-based measurement of adherence in postpartum HIV-infected women

Abstract

Background: Antiretroviral treatment for HIV-infected women is standard during pregnancy to prevent vertical transmission, but data on postpartum therapy for the mother are lacking.

Objective: The objective of this study was to examine the impact of provider and patient characteristics on receipt of antiretroviral therapy and pharmacy-based measurement of adherence by postpartum HIV-infected women.

Research design: This was a retrospective cohort study.

Subjects: The study included 2,648 New York State Medicaid-enrolled HIV-infected women who delivered from January 1993 through October 1996 and were followed up through September 1997.

Measures: From Medicaid claims in the first postpartum year, the study examined any prescribed antiretroviral therapy and, among women treated >2 months, adherence, defined as > or =80% days covered by prescribed therapy from first to last antiretroviral prescription.

Results: Antiretroviral therapy was prescribed for 681 (26%) study women. Of 292 women treated >2 months, 28% were adherent on the basis of the pharmacy-based measure. The proportion of treated women was highest in 1996 (40%), and adherence was best in 1995 (44%) when most women took monotherapy. The adjusted odds ratios (AORs) of treatment were 1.67 (95% CI, 1.24 to 2.25) for women receiving HIV-focused services and 2.71 (95% CI, 1.99 to 3.69) for women with a provider in an HIV-related specialty. The AORs of adherence were greater for women with HIV-focused services (2.13; 95% CI, 1.05 to 4.30) and for former illicit drug users versus nonusers (2.40; 95% CI, 1.05 to 5.50).

Conclusions: This population-based pharmacy analysis reveals improving antiretroviral use but continuing poor pharmacy-based adherence by postpartum HIV-infected women. Receipt of HIV-focused services appears to be particularly beneficial in increasing the likelihood of treatment and adherence.