Prevalence and clinical impact of drug–drug interactions in geriatric patients with polypharmacy

Aslı Gizem Tıraşçı; Nur Düzen Oflas

doi:10.47582/jompac.1848501

Prevalence and clinical impact of drug–drug interactions in geriatric patients with polypharmacy

Abstract

Aims: This study aimed to determine the prevalence and severity of drug-drug interactions (DDIs) and their clinical outcomes in patients aged 65 years and above with polypharmacy attending internal medicine outpatient clinics. Methods: A retrospective analysis was conducted on patients aged 65 and over who visited the Internal Medicine Outpatient Clinic at Van Yüzüncü Yıl University Medical Center between June 1, 2024, and February 1, 2025. Patients using ≥5 medications for chronic diseases (excluding those with active malignancy or on routine hemodialysis) were included. DDIs were evaluated using the Lexicomp® Drug Interactions Database and classified into risk categories A, B, C, D, and X. Clinical and laboratory parameters were compared between polypharmacy (5-9 drugs) and multipolypharmacy (≥10 drugs) groups. Results: A total of 259 patients were included (mean age: 72.8±6.3 years; 55.2% female). The most prevalent chronic conditions were hypertension (95.4%), coronary artery disease (76.1%), and diabetes mellitus (61.8%). Patients in the multipolypharmacy group had significantly higher rates of coronary artery disease (100% vs. 74.2%, p=0.011) and chronic kidney disease (89.5% vs. 34.6%, p<0.001). They also demonstrated significantly lower glomerular filtration rate (37.9±9.3 vs. 59.6±22.9 ml/min/1.73m², p<0.001) and higher HbA1c levels (7.72±1.48% vs. 7.08±1.98%, p=0.021). Category C drug interactions were most common across all patients (91.9%), while category D interactions requiring therapy modification were significantly more prevalent in the multipolypharmacy group (57.9% vs. 24.6%, p=0.002). Conclusion: DDIs are inevitable in polypharmacy. Patients using ≥10 medications demonstrate higher rates of chronic kidney disease and uncontrolled diabetes, with significantly increased prevalence of clinically significant drug interactions requiring therapeutic intervention. Regular medication review and monitoring are essential for elderly patients with polypharmacy.

Keywords

Ethical Statement

ETHICS COMMITTEE APPROVAL REPUBLIC OF TÜRKİYE VAN YÜZÜNCÜ YIL UNIVERSITY NON-INTERVENTIONAL CLINICAL RESEARCH ETHICS COMMITTEE DECISION FORM FULL TITLE OF THE STUDY Prevalence and Clinical Outcomes of Drug–Drug Interactions in Patients Aged 65 Years and Older Admitted to Internal Medicine Outpatient Clinics: A Retrospective Analysis PRINCIPAL INVESTIGATOR Assist. Prof. Dr. Nur DÜZEN OFLAS Department of Internal Medicine Van Yüzüncü Yıl University Faculty of Medicine DECISION The above-mentioned study was reviewed by the Van Yüzüncü Yıl University Non-Interventional Clinical Research Ethics Committee. It was determined that the study complies with ethical standards and relevant regulations. The committee unanimously decided that there is no ethical objection to conducting this study. Decision No: 2025/08-39 Decision Date: 26/08/2025

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Details

Primary Language

English

Subjects

Geriatrics and Gerontology

Journal Section

Research Article

Authors

Aslı Gizem Tıraşçı
0009-0000-6606-2309
Türkiye

Nur Düzen Oflas ^*
0000-0003-0897-2819
Türkiye

Publication Date

February 20, 2026

Submission Date

December 24, 2025

Acceptance Date

January 22, 2026

Published in Issue

Year 2026 Volume: 7 Number: 1

DOI

https://doi.org/10.47582/jompac.1848501

IZ

https://izlik.org/JA33UC22FT

Cite

RIS / Bibtex

APA

Tıraşçı, A. G., & Düzen Oflas, N. (2026). Prevalence and clinical impact of drug–drug interactions in geriatric patients with polypharmacy. Journal of Medicine and Palliative Care, 7(1), 46-51. https://doi.org/10.47582/jompac.1848501

AMA

1.Tıraşçı AG, Düzen Oflas N. Prevalence and clinical impact of drug–drug interactions in geriatric patients with polypharmacy. J Med Palliat Care / JOMPAC / jompac. 2026;7(1):46-51. doi:10.47582/jompac.1848501

Chicago

Tıraşçı, Aslı Gizem, and Nur Düzen Oflas. 2026. “Prevalence and Clinical Impact of Drug–drug Interactions in Geriatric Patients With Polypharmacy”. Journal of Medicine and Palliative Care 7 (1): 46-51. https://doi.org/10.47582/jompac.1848501.

EndNote

Tıraşçı AG, Düzen Oflas N (February 1, 2026) Prevalence and clinical impact of drug–drug interactions in geriatric patients with polypharmacy. Journal of Medicine and Palliative Care 7 1 46–51.

IEEE

[1]A. G. Tıraşçı and N. Düzen Oflas, “Prevalence and clinical impact of drug–drug interactions in geriatric patients with polypharmacy”, J Med Palliat Care / JOMPAC / jompac, vol. 7, no. 1, pp. 46–51, Feb. 2026, doi: 10.47582/jompac.1848501.

ISNAD

Tıraşçı, Aslı Gizem - Düzen Oflas, Nur. “Prevalence and Clinical Impact of Drug–drug Interactions in Geriatric Patients With Polypharmacy”. Journal of Medicine and Palliative Care 7/1 (February 1, 2026): 46-51. https://doi.org/10.47582/jompac.1848501.

JAMA

1.Tıraşçı AG, Düzen Oflas N. Prevalence and clinical impact of drug–drug interactions in geriatric patients with polypharmacy. J Med Palliat Care / JOMPAC / jompac. 2026;7:46–51.

MLA

Tıraşçı, Aslı Gizem, and Nur Düzen Oflas. “Prevalence and Clinical Impact of Drug–drug Interactions in Geriatric Patients With Polypharmacy”. Journal of Medicine and Palliative Care, vol. 7, no. 1, Feb. 2026, pp. 46-51, doi:10.47582/jompac.1848501.

Vancouver

1.Aslı Gizem Tıraşçı, Nur Düzen Oflas. Prevalence and clinical impact of drug–drug interactions in geriatric patients with polypharmacy. J Med Palliat Care / JOMPAC / jompac. 2026 Feb. 1;7(1):46-51. doi:10.47582/jompac.1848501