Influence of the number of daily pills and doses on adherence to antiretroviral treatment: a 7-year study.

WHAT IS KNOWN AND OBJECTIVE: Antiretroviral treatment (ART) is hampered by complicated regimens, high pill burden, drug-drug interactions, and frequent short- and long-term adverse effects, leading to decreased adherence. Over recent years, considerable effort has been directed at developing regimens that are less burdening. We undertook a 7-year retrospective study of the records of 264 HIV-infected subjects enrolled in a pharmaceutical care programme to document the progress made and to study the influence of the number of ART pills and doses on the level of treatment adherence. METHODS: Antiretroviral dispensing records were analysed for the number of pills and doses administered and the ART adherence rate estimated. RESULTS AND DISCUSSION: In 2005, the patients took a mean of 6·2 pills daily (CI 95%: 5·9-6·6), and 92·9% of them were on a twice-a-day (BID) dosage regimen. By 2012, the mean number of pills was reduced to 4·1 (CI 95%: 3·8-4·4), and only 50·9% were on a BID regimen. No statistically significant relation was observed between number of daily pills and doses and ART adherence reached by the patients in any of the analyses performed. WHAT IS NEW AND CONCLUSIONS: There has been a continuous reduction in the number of pills and doses of antiretrovirals taken by individual patients over the last 7 years due largely to the introduction of improved treatments and regimens. More daily pills or doses was not associated with worse ART adherence in our pharmaceutical care programme.

[Development and validation of a prediction model to identify HIV+ patients with drug-related problems. A prediction study]. / Desarrollo y validación de un modelo predictivo para la identificación de pacientes infectados por el VIH con problemas relacionados con los medicamentos. Estudio predictor.

OBJECTIVE: To develop and validate a prediction model for the detection of drug-related problems (DRP) in patients on antiretroviral treatment during their regular monitoring in Pharmaceutical Care Clinics before dispensing drugs. MEHOD: Open multicentre prospective study. HIV patients with and without DRP were included. Demographic, clinical and pharmacotherapy variables (related and unrelated to antiretroviral treatment) were included in the model design. To find prognostic factors for DRP, a binary logistic regression model was created after performing a univariate analysis that identified independent variables related to DRP these variables were introduced in the multivariate model for the final selection. Model validity was determined by the shrinkage method and the discriminatory power by Harrell's C-index. RESULTS: 733 patients were included. The variables "adherence", "prescription of drugs needing dosage adjustment", and "total number of drugs prescribed (apart from the antiretroviral treatment)" were independently related to the appearance of DRP. Probabilities predicted by the model, customising the coefficients using the uniform shrinkage method, showed a R(2)=0.962 for the construction sample and a R(2)=0.872 for the validation sample. The discriminatory capacity of the model was 0.816 for the construction sample and 0.779 for the validation sample. CONCLUSIONS: The developed and validated model enables detection of patients on antiretroviral treatment who are at a higher risk for experiencing a DRP. The prediction variables employed are commonly used in patient's pharmacotherapy record, allowing the model to be used in routine clinical practice.