Antiretroviral drug adherence is critical, and treatment should be closely monitored for indications of HIV progression such as a decrease in CD4-cell levels and an increase in viral load, said Sabina De Geest of the University of Basel, Switzerland. Using data from the Swiss HIV Cohort Study, De Geest and colleagues sought to determine the prevalence of self-reported antiretroviral adherence and to explore the relationships among socioeconomic, patient, and systematic factors related to adherence.
Data showed that nearly one third of patients acknowledged missing at least one dose of medicine in the four weeks prior to completing the questionnaire, the researchers reported. Around 15% said they missed at least two doses, and 7.1% said they took less than 95% of prescribed antiretroviral therapy doses.
Irrespective of the definition of adherence used, patients who were younger, lived alone, had been on previous anti-HIV drug regimens, and those who received a boosted protease inhibitor regimen were significantly more likely to have not adhered to therapy in the past four weeks, the researchers found. Those patients with optimal viral suppression in the previous six months and those with CD4-cell count increases of more than 50 cells per microliter were considerably more likely to have adhered to treatment.
"An interesting finding of this study was that we observed a center effect," De Geest noted. "Adherence ranged among centers between 26.1% and 41.5%. This observed center effect is a novel finding and suggests that system factors related to how care is organized and provided also are associated with nonadherence." (Reuters)
