Background There is a high prevalence of multimorbidity and polypharmacy among older people, especially in people living with HIV (PLWH) with an increased life expectancy due to effective antiretroviral therapy (ART). Consequently, there is a higher risk of potentially inappropriate medications (PIM), potential drug-drug interactions (DI), and problems of non-adherence to treatment (NAC) in older PLWH. PIMDINAC criteria (potentially inappropriate medications (PIM), drug–drug interactions (DI), and non-adherence to treatment (NAC)) purport to jointly analyse these problems. The purpose of the study was to compare the prevalence of PIMDINAC criteria among elderly PLWH and non-infected patients with chronic diseases, and to determine whether HIV infection constitutes a predictor of the presence of PIMDINAC criteria, totally or partially.

Methods A cross sectional study was conducted between February and June 2020. HIV positive patients aged ≥65 years were compared with a group of patients with chronic conditions attending the outpatient hospital pharmacy service.

Results The study involved 140 patients: 47 HIV positive and 93 HIV negative, and mean age was 69 versus 73 years, respectively (p=0.062). The prevalence of total PIMDINAC criteria was similar between the groups (12.5 vs 10.8%, p=0.505). In relation to inappropriate medication, no differences were observed between groups (48.9 vs 55.9%, p=0434). Drug–drug interactions were higher in patients with chronic conditions (52.7 vs 25.5%, p=0.002) compared with non-adherence, which was higher in people with HIV (22.6 vs 65.6%, p<0.001). No differences in polypharmacy (≥6 and 11 drugs) rates were observed.

Conclusions PIMDINAC criteria were highly prevalent in older PLWH, similar to non-infected patients. HIV infection in older people was associated with a lower risk of drug–drug interactions. However, non-adherence was a risk factor compared with age matched controls. Deprescribing strategies, including a capability–motivation–opportunity pharmaceutical care model based intervention should be implemented in clinical routines.