Monitoring Drug Interactions in Aging Patients With HIV

Seventy percent of individuals with HIV will be 50 years or older by 2020. With the aging of the HIV-positive population and the necessity of using multiple medications — many of which have significant potential for drug interactions – it's important to look for ways that we can minimize risk for this population.

The journal Pharmacotherapy has published a study that examines how pharmacists can reduce polypharmacy and potentially inappropriate prescribing. Conducted by a team of investigators from numerous HIV-associated organizations in San Francisco, California, the study reveals that pharmacists who target individuals with HIV who take 11 or more chronic medications have the potential to have the most impact.

The investigators searched computerized electronic medical records to identify patients who were 50 years of age and older and had a primary care appointment within the previous year. The study ultimately enrolled 248 patients from 857 individuals who were eligible. Patients mean age was 58 years. The mean CD4 count was 536 cells/mm³.

The investigators identified the most common comorbidities. These included hypertension and depression in more than half of study participants, and asthma/chronic obstructive pulmonary disease (48%), dyslipidemia (39%), coronary artery disease (27%, and diabetes (22%).

The pharmacists used the Beers Criteria and Screening Tool of Older Persons' Potentially Inappropriate Prescriptions (STOPP) to identify prescribing problems, and each review took approximately 45 minutes. These tools were originally developed for populations that did not have HIV, and the purpose of this study was to validate their use with in a population of people who had HIV.

The mean number of prescription medications was 11.6 excluding antiretrovirals, and 14 if antivirals were included. More than one third of participants were taking 16 medications or more.

Pharmacists identified potentially inappropriate prescribing in 54% when they used the STOPP and 63% of patients when they use the Beers Criteria. The pharmacist noted that in patients who were taking more than 11 medications, the likelihood of inappropriate prescribing was significantly higher than in those who were taking fewer.

Pharmacist intervention resulted in the discontinuation of at least 1 medication in 69% of patients and 6 or more medications in 10% of patients.

The authors emphasized that in this study, the medication review was prospective in nature and not retrospective.

Reference

McNicholl IR, Gandhi M, Hare CB, et al. A Pharmacist-Led Program to Evaluate and Reduce Polypharmacy and Potentially Inappropriate Prescribing in Older, HIV-Positive Patients. Pharmacotherapy. 2017 Oct 10. doi: 10.1002/phar.2043. [Epub ahead of print]

This article was originally published by Pharmacy Times.