Polypharmacy and the Risk of Adverse Drug Reactions in the Elderly at a Tertiary Referral Hospital in Indonesia: Assessing the Applicability of the GerontoNet Score.

Background: Geriatric patients are often subject to polypharmacy, increasing their risk of adverse drug reactions (ADRs). This study evaluated polypharmacy practices, ADR incidence, predictive factors, and the applicability of the GerontoNet Score at a tertiary referral teaching hospital in Indonesia.

Methods: This retrospective study included 340 geriatric inpatients at Dr. Cipto Mangunkusumo Hospital, Jakarta, in 2023. The relationship between demographic data, comorbidities, number of drugs used, and ADR events was analyzed using the Chi-square test. The association between GerontoNet ADR scores and ADR events was also assessed.

Results: The study included 182 (53.5%) male and 158 (46.5%) female patients, with a mean age of 71.9±6.1 years. Of these, 70.9% were aged 65 to 74. A total of 78.8% of patients had ≥ 4 comorbidities. The number of drugs ranged from 3 to 28, with a mean of 10.7 drugs and a median of 10 drugs. ADRs were detected in 26 patients (7.6%), with 17 cases in females and 9 in males (p=0.044). Insulin- and diuretic-induced hypokalemia were the most frequent ADR (13 patients), followed by heparin-induced thrombocytopenia (3 patients). No significant correlation was found between ADRs and age (p=0.505), number of comorbidities (p=0.425), number of drugs (p=0.576), or GerontoNet ADR Score (p=0.530).

Conclusion: Polypharmacy is prevalent at Dr. Cipto Mangunkusumo Hospital, yet the incidence of ADRs is relatively low. Most ADRs were related to high-alert drugs, while no significant correlations were found between age, polypharmacy, comorbidities, or GerontoNet Score with ADR events.