Multimorbidity and Polypharmacy in People With HIV vs. the General Population in the Basque Country

A Comparative Study on the Prevalence of Multimorbidity, Polypharmacy and Potentially Inappropriate Prescriptions Among the General Population and People Living With HIV in the Basque Country

People living with HIV now have a life expectancy similar to that of the general population, thanks to major advances in antiretroviral treatment. As they live longer, many of them experience multiple health conditions at the same time and take several medications, often more than people without HIV. In our region, 6,273 people are currently receiving antiretroviral therapy. However, the new care pathway designed for patients with multiple chronic conditions in the Basque Country's public health system does not include people with HIV. At the same time, we lack local data on how common multimorbidity, polypharmacy, and potentially inappropriate prescribing are among this group. These gaps motivated our study. Our goal is to estimate how frequent these issues are among all people with HIV who receive care in the infectious disease departments of the hospitals in Araba, Basurto, Galdakao, Cruces, and Donostia, and to compare them with a similar group of people without HIV. To do this, we designed a cross-sectional study including the 6,273 people with HIV and a control group from the general population, selected to match them by age, sex, and health centre. By analysing data from electronic health records, we aim to determine whether people with HIV have higher rates of multimorbidity, polypharmacy, and inappropriate prescribing than the general population. The findings from both groups will help us update the care pathway and improve coordinated care for HIV-positive patients with multiple health conditions.

Study Overview

• Status: Not yet recruiting
• Conditions: HIV (Human Immunodeficiency Virus)
• Intervention / Treatment: Other: No intervention

Detailed Description

Advances in antiretroviral treatment for people living with Human Immunodeficiency Virus (HIV) have brought their life expectancy into line with that of the general population. These individuals now have a higher prevalence of multiple co-morbidities and polypharmacy than the general population.

According to the latest report on the AIDS plan, there are 6,273 patients in our region currently receiving antiretroviral treatment. However, the recent corporate care pathway for people with multiple co-morbidities in the Basque Country's public health system does not include patients with HIV. This fact, together with the lack of data on the prevalence of multiple co-morbidities, polypharmacy and potentially inappropriate prescribing among these individuals in our region, motivated the conduct of this study. Its aim is to estimate this prevalence among all people with HIV receiving care in the infectious diseases departments of the hospitals in Araba, Basurto, Galdakao, Cruces and Donostia, and to compare it with a control group without HIV. To this end, we designed a cross-sectional comparative study involving 6,273 people with HIV and a control group drawn from the general population through stratified sampling according to the distribution by age, sex and health centre of the HIV population. The results, obtained by extracting data from electronic health records, will enable us to confirm whether the HIV-positive population has a higher prevalence of multimorbidity, polypharmacy and inappropriate prescribing than the general population. The results obtained from both populations will provide us with the necessary knowledge to update the corporate care pathway and to plan coordinated care for HIV-positive patients with multimorbidity.

• Study Type: Observational
• Enrollment (Estimated): 12546

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: Yes

• Sampling Method: Probability Sample

Study Population

People with HIV aged 18 or over who are being monitored by the infectious diseases departments of the Araba, Cruces, Basurto and Donostia University Hospitals and the Galdakao-Usansolo Hospital, all part of Osakidetza. Five HIV-negative controls will be selected for each person with HIV. Stratified random sampling will be carried out by age, sex and referral hospital, according to the composition of the HIV population.

Description

Inclusion Criteria:

• People with HIV aged 18 or over
• Being monitored by the infectious diseases departments of the Araba, Cruces, Basurto and Donostia University Hospitals and the Galdakao-Usansolo Hospital, all part of Osakidetza.

Exclusion Criteria:

- Being under 18 years of age

Study Plan

How is the study designed?

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
People with HIV; People with HIV aged 18 years or over receiving care in the infectious diseases departments of the hospitals in Araba, Basurto, Galdakao, Cruces and Donostia.	Other: No intervention; No intervention
General population; General population through stratified sampling according to the distribution by age, sex and health centre of the HIV population	Other: No intervention; No intervention

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Prevalence of multimorbidity in people with HIV in the Basque Country	Proportion of people with HIV aged ≥18 years who have ≥2 chronic diseases recorded in their electronic health records. Automated extraction of active diagnoses coded in the electronic health records.	Enrollment
Prevalence of multimorbidity in the general population in the Basque Country	Proportion of people aged ≥18 years who have ≥2 chronic diseases recorded in their electronic health record. Automated extraction of active diagnoses coded in the electronic health records.	Enrollment
Prevalence of polypharmacy in people with HIV in the Basque Country	Proportion of people with HIV aged ≥18 years who have ≥5 prescribed medications and ≥10 medications (excessive polypharmacy) as chronic or on demand treatments, excluding antiretroviral therapy. Adherence according to the dispensing records.	Enrollment
Prevalence of polypharmacy in the general population in the Basque Country	Proportion of people aged ≥18 years who have ≥5 prescribed medications and ≥10 medications (excessive polypharmacy) as chronic or on demand treatments, excluding antiretroviral therapy. Adherence according to the dispensing records.	Enrollment
Prevalence of potentially inappropriate prescriptions in people with HIV in the Basque Country	Proportion of people with HIV aged ≥18 years who present potentially inappropriate prescriptions according to the STOPP/START criteria: duplications, exceeded maximum doses, contraindicated or severe interactions, anticholinergic burden in people over 70 years of age, and exceeded treatment duration.	Enrollment
Prevalence of potentially inappropriate prescriptions in the general population in the Basque Country	Proportion of people aged ≥18 years who present potentially inappropriate prescriptions according to the STOPP/START criteria: duplications, exceeded maximum doses, contraindicated or severe interactions, anticholinergic burden in people over 70 years of age, and exceeded treatment duration.	Enrollment

Collaborators and Investigators

• Sponsor: Biogipuzkoa Health Research Institute

Study record dates

Study Major Dates

• Study Start (Estimated): September 1, 2026
• Primary Completion (Estimated): October 1, 2026
• Study Completion (Estimated): October 1, 2026

Study Registration Dates

• First Submitted: May 27, 2026
• First Submitted That Met QC Criteria: May 27, 2026
• First Posted (Actual): June 2, 2026

Study Record Updates

• Last Update Posted (Actual): June 12, 2026
• Last Update Submitted That Met QC Criteria: June 10, 2026
• Last Verified: June 1, 2026

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Blood-Borne Infections; Urogenital Diseases; Genital Diseases; Immune System Diseases; Infections; RNA Virus Infections; Virus Diseases; Communicable Diseases; Sexually Transmitted Diseases, Viral; Sexually Transmitted Diseases; Lentivirus Infections; Retroviridae Infections; Immunologic Deficiency Syndromes; Slow Virus Diseases; HIV Infections; Acquired Immunodeficiency Syndrome
• Other Study ID Numbers: 2023111044

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No