# A Single-Center Prospective Study on Adverse Drug Reactions Associated With Polypharmacy in Elderly Outpatients

## TL;DR

This study finds that elderly outpatients taking many medications are at higher risk for adverse drug reactions, especially those over 80 or with multiple health conditions.

## Contribution

A prospective observational study quantifying ADR frequency and risk factors in elderly outpatients with polypharmacy.

## Key findings

- 30.89% of elderly outpatients on multiple medications experienced adverse drug reactions.
- ADRs were more common in patients aged ≥80, those on ≥9 medications, and those with multiple comorbidities.
- Gastrointestinal and dermatological systems were most frequently affected by ADRs.

## Abstract

Background: Polypharmacy in elderly patients significantly increases the risk of adverse drug reactions (ADRs), posing a challenge to safe outpatient care.

Objective: To prospectively evaluate the frequency, nature, and clinical outcomes of ADRs associated with polypharmacy in elderly outpatients.

Methodology: A prospective observational study was conducted at the outpatient department of Azad Jammu and Kashmir Medical College (AJKMC), Muzaffarabad, over one year from June 2023 to May 2024. Through convenience sampling, 246 individuals who were at least 60 years old and using five or more drugs were included. Medical record reviews and structured patient interviews were used to gather data. The FDA Toxicity Grading Scale was used to classify ADRs according to their severity after they were evaluated using the FDA Toxicity Grading Scale. SPSS version 25.0 (IBM Corp., Armonk, NY) was used for the statistical analysis, and P < 0.05 was chosen as the significance level.

Results: Of the 246 patients, 132 patients (53.66%) were male and 114 patients (46.34%) were female. The most common comorbidities were hypertension in 151 patients (61.38%), type 2 diabetes mellitus in 103 patients (41.87%), and ischemic heart disease in 89 patients (36.18%). Regarding polypharmacy, 94 patients (38.21%) were taking 5-6 medications, 87 patients (35.37%) were on 7-8 medications, and 65 patients (26.42%) were on 9 or more medications. A total of 76 patients (30.89%) experienced at least one ADR. The most frequently affected systems were gastrointestinal in 28 patients (11.38%) and dermatological in 17 patients (6.91%). ADRs were significantly more common in patients aged ≥80 years (16 out of 41, 39.02%), in those taking ≥9 medications (30 out of 65, 46.15%), and in those with two or more comorbidities (52 out of 121, 43.70%) (P < 0.05 for all comparisons).

Conclusions: Polypharmacy in elderly outpatients is strongly associated with clinically significant ADRs, warranting routine medication review and vigilant pharmacovigilance.