Background The expected lifespan of HIV +patients has increased dramatically as a result of improved antiretroviral therapy (ART), with the consequent increase in comorbidities and polypharmacy.

Purpose To analyse the profile of comorbidities and polypharmacy in HIV +patients of a Health Area and determine their influence on the risk of presenting drug-related problems (DRPs) and potential clinically significant drug interactions (CSDIs).

Material and methods Retrospective observational study conducted in a Reference Hospital Area that treated 457 HIV +patients with ART. We included all HIV +patients who collected ART in our pharmacy service during a randomly chosen week of March 2018. Variables included in the analysis were: demographics (age, sex) and clinical (viral load (VL), comorbidities) from computerised medical records and pharmacotherapeutic (ART scheme, dispensing data and concomitant treatment) from a management programme (Savac) and application AGORA PLUS®. Patients with ≥2 chronic non-AIDS pathologies were considered pluripathologic and polymedicated if they were prescribed ≥5 non-ART drugs. The risk of DRPs was obtained from the PREDICTOR tool of the Spanish Society of Hospital Pharmacy and CSDIs from the Lexicomp database. Statistical analysis was performed using SPSS v23.0.

Results We included 120 patients (76.7% males), with a mean age of 51.15±9.61 years (59.17%>50 years’ old). 94.17% had undetectable VL. 54.2% patients were pluripathologic with a median of three (2–4) comorbidities and 26.7% polymedicated with a median of seven (6–9) drugs per patient. The most common chronic diseases were: anxiety/depression (45.8%), dyslipidaemia (32.5%), hypertension (20.8%) and psychiatric disorders (19.2%). Benzodiazepines (32.5%), vitamin D (31.7%), proton-pump inhibitors (22.5%), statins (20%), antidepressants (18.3%) and antipsychotics (15%) were the most common drugs prescribed.

A total of 55 CSDIs were identified in 41 patients (34.2% of patients), of which 78.18% involved ARV drugs. Classes of drugs most involved in CSDIs were: pharmacokinetic enhancers (40%), protease inhibitors (38.18%), statins (25.45%), antipsychotics (25.45%) and antidepressants (14.54%). The risk of DRPs was high in 46.7% of patients. In statistical analysis (Mann–Whitney U test), the relationship between the number of comorbidities and the risk of DRPs and CSDIs was statistically significant (p<0.005) in both cases.

Conclusion The results of the study demonstrate the aging of the HIV +population and the consequences that this entails: an increased risk of presenting DRPs as well as the risk of CSDIs. Due to this, a meticulous and multidisciplinary approach is necessary in this population in order to identify the most susceptible patients.

References and/or acknowledgements No conflict of interest.