How late is too late? Timeliness to scheduled visits as an antiretroviral therapy adherence measure in Nairobi, Kenya and Lusaka, Zambia.

Collecting self-reported data on adherence to highly active antiretroviral therapy (HAART) can be complicated by patients' reluctance to report poor adherence. The timeliness with which patients attend visits might be a useful alternative to estimate medication adherence. Among Kenyan and Zambian women receiving twice daily HAART, we examined the relationship between self-reported pill taking and timeliness attending scheduled visits. We analyzed data from 566 Kenyan and Zambian women enrolled in a prospective 48-week HAART-response study. At each scheduled clinic visit, women reported doses missed over the preceding week. Self-reported adherence was calculated by summing the total number of doses reported taken and dividing by the total number of doses asked about at the visit attended. A participant's adherence to scheduled study visits was defined as "on time" if she arrived early or within three days, "moderately late" if she was four-seven days late, and "extremely late/missed" if she was more than eight days late or missed the visit altogether. Self-reported adherence was <95% for 29 (10%) of 288 women who were late for at least one study visit vs. 3 (1%) of 278 who were never late for a study visit (odds ratios [OR] 10.3; 95% confidence intervals [95% CI] 2.9, 42.8). Fifty-one (18%) of 285 women who were ever late for a study visit experienced virologic failure vs. 32 (12%) of 278 women who were never late for a study visit (OR 1.7; 95% CI 1.01, 2.8). A multivariate logistic regression model controlling for self-reported adherence found that being extremely late for a visit was associated with virologic failure (OR 2.0; 95% CI 1.2, 3.4). Timeliness to scheduled visits was associated with self-reported adherence to HAART and with risk for virologic failure. Timeliness to scheduled clinic visits can be used as an objective proxy for self-reported adherence and ultimately for risk of virologic failure.

Effectiveness of a city-wide program to prevent mother-to-child HIV transmission in Lusaka, Zambia.

OBJECTIVE: To determine the population effectiveness of a city-wide perinatal HIV prevention program. DESIGN: An anonymous surveillance of newborn cord blood for HIV serology and nevirapine (NVP). METHODS: All 10 public-sector delivery centers in Lusaka, Zambia participated. All mother-infant pairs delivering during the 12-week surveillance period at the participating centers and who received antenatal care at a public-sector facility in Lusaka were included in the study. The main outcome measure was population NVP coverage, defined as the proportion of HIV-infected women and HIV-exposed infants in the population that ingested NVP. RESULTS: Of 8787 women in the surveillance population, 7204 (82%) had been offered antenatal HIV testing, of which 5149 (71%) had accepted, and of which 5129 (99%) had received a result. Overall, 2257 of 8787 (26%) were cord seropositive. Of the 1246 (55%) cord blood seropositive women who received an antenatal HIV test result, 1112 (89%) received a positive result; the other 134 comprise seroconverters and clerical errors. Only 751 of 1112 (68%) women who received a positive antenatal test result and a NVP tablet for ingestion at labor onset had NVP detected in the cord blood (i.e., maternal non-adherence rate was 32%). A total of 675 infants born to 751 adherent mothers (90%) received NVP before discharge. Thus, only 675 of 2257 (30%) seropositive mother-infant pairs in the surveillance population received both a maternal and infant dose of NVP. CONCLUSIONS: Successful perinatal HIV prevention requires each mother-infant pair to negotiate a cascade of events that begins with offering HIV testing and continues through adherence to the prescribed regimen. This novel surveillance demonstrates that failures occur at each step, resulting in reduced coverage and diminished program effectiveness.

Do targeted HIV programs improve overall care for pregnant women?: Antenatal syphilis management in Zambia before and after implementation of prevention of mother-to-child HIV transmission programs.

BACKGROUND: The implementation of disease-specific research or service programs may have an ancillary beneficial or harmful impact on routine clinical services. METHODS: We reviewed the records of 5801 first visits to 22 antenatal clinics from 1997 to 2004 in Lusaka, Zambia and examined documented syphilis rapid plasma reagin (RPR) screening and syphilis treatment before and after implementation of research and/or service programs in prevention of mother-to-child (PMTCT) HIV transmission. FINDINGS: Compared with before PMTCT program implementation, the prevalence odds ratios (PORs) and 95% confidence intervals (CIs) for documented RPR screening were 0.9 (0.7 to 1.1) after implementation of research, 0.7 (0.6 to 0.8) after service, and 2.5 (2.1 to 3.0) after research and service programs. CONCLUSIONS: Documented RPR screening was improved after implementation of PMTCT research and service were operating simultaneously and not with research or service alone. Health policy makers and researchers should plan explicitly for how the targeted HIV programs, service, and/or research can have a broader primary care impact.