Prevalence of Polypharmacy and Association to Pharmacotherapy Complexity in Older HIV-Positive Patients. The Sevihlla Study

Abstract

Background: Increased life expectancy of older HIV-positive patients has been associated to a parallel increase in age-related comorbidities. Objectives: To ascertain the prevalence of polypharmacy and its association to pharmacotherapy complexity, as measured by the Medication Regimen Complexity Index, in older HIV-positive patients; to calculate the median value of pharmacotherapy complexity; to identify polypharmacy and multimorbidity patterns; and to address adherence to antiretroviral and concomitant drugs. Methods: A cross-sectional, observational study was conducted in patients over 50 years of age receiving active antiretroviral drugs during 2014 at outpatient pharmacy services of a tertiary hospital in Spain. Data collected from the electronic medical record included demographic, clinical and comorbidity related endpoints. The primary endpoint was the proportion of patients with polypharmacy and major polypharmacy. Polypharmacy was defined as treatment with six or more drugs (including antiretroviral). Major polypharmacy (more than 11 drugs) was also considered. Patients was categorized according to their polypharmacy pattern. Three patterns were applied based on age of participants: cardiovascular, depression-anxiety, and chronic obstructive pulmonary (COPD) disease patterns. A patient was classified into a pattern when at least three drugs of the treatment were in the same pattern. Antiretroviral treatment adherence was measured using the SMAQ questionnaire and hospital dispensing records. Adherence to concomitant medication was measured using the Morisky-Green questionnaire and electronic pharmacy dispensing records. Pharmacotherapy complexity index, as assessed by MRCI, was also considered. Patients were classified as low MRCI (less than 14 points) or high MRCI (more than 14 points). Results: The study sample consisted of 223 patients (86.5% men), with a median age of 53.0 years. More than 80.0% of the patients were viro-inmunological controlled. Prevalence of polypharmacy was 56.1%. The median value of pharmacotherapy complexity was 11.0. The main contribution to this value was from the concomitant medication. The polypharmacy pattern mainly calculated was cardiovascular (60.0%) and the multimorbidity pattern was cardiometabolic (73.8%). Presence of polypharmacy was associated to greater pharmacotherapy complexity (p<0,001). Adequate adherence to the antiretroviral and to concomitant medication was found in 83.6% and 37.9% of patients respectively. Conclusions: More than a half of the older HIV-positive patients received six or more different drugs with a significant pharmacotherapy complexity showing adequate adherence to antiretroviral but not to concomitant drugs. Cardiovascular conditions were most common in terms of prescriptions and comorbidities.