Top 20 drug - drug interactions, polypharmacy and analysis of the nature of risk factors due to QT interval prolonging drug use in elderly psychiatry outpatients

• Published in: Journal of family medicine and primary care Vol. 9; no. 12; pp. 6023 - 6040
• Main Authors: Das, Biswadeep, Ramasubbu, Saravana Kumar, Kumar, Barun, Rawat, Vikram Singh
• Format: Journal Article
• Language: English
• Published: India Medknow Publications and Media Pvt. Ltd 01.12.2020; Wolters Kluwer - Medknow; Wolters Kluwer Medknow Publications
• Subjects: Aged patients; Complications and side effects; Coronary heart disease; Droperidol; Drospirenone; Drug interactions; drug-induced qt prolongation; elderly patients; Electrocardiogram; Electrocardiography; Medical research; Medicine, Experimental; Original; Pantoprazole; psychiatry opd; psychotropic drugs; Rankings; Risk factors; Sparfloxacin; Thioridazine; torsade de pointes; India; elderly patients; psychiatry OPD; psychotropic drugs; Torsade de pointes; Drug-induced QT prolongation
• ISSN: 2249-4863; 2278-7135
• DOI: 10.4103/jfmpc.jfmpc_1060_20

Psychotropic medications extend the corrected QT (QTc) period in the ECG. Psychiatric patients exposed to ≥ 1 psychotropic medication (s) represent a group with a marked probability of drug-activated QTc-prolongation. Prolonged QTc interval in elderly patients (age > 60 years) is connected to a greater risk of all-cause and coronary heart disease deaths. We investigated the pattern of utilization of QTc-interval prolonging medications, QT-extending interactions between drugs, and prevalence of QTc-interval prolonging risk factors in elderly patients. This was a cross-sectional, prospective study at the Psychiatry OPD at All India Institute of Medical Sciences (AIIMS), Rishikesh, Uttarakhand, India from October 1, 2017 to December 31, 2018 employing the pertinent prescriptions. A total of 208 elderly patients (age 60 years or more) visiting the Psychiatry OPD during the aforementioned study period were investigated. 105 (50.5%) patients were males whereas 103 (49.5%) were females in our study. 147 out of 208 patients (70.7%) were using interacting agents with the capacity to produce TdP. 288 interacting torsadogenic medication pairs were unraveled. As per AzCERT/CredibleMeds Classification, 254 (48.8%), 181 (34.8%), and 62 (12%) interacting medications were identified with known, possible, and conditional risk of TdP, respectively. The common interacting medications belonged to antidepressant (144), proton pump inhibitor (91), antipsychotic (85), anti-nausea (46), antimicrobial (39), and H receptor antagonist (15) therapeutic categories. Many geriatric patients were administered drugs and drug combinations with heightened proclivity towards QT-interval prolongation. Therefore, we need to exigently embrace precautionary safety interventions, to be vigilant, and forestall QT-prolongation and TdP in clinical settings. Online evidence-based drug information resources can aid clinicians in choosing drugs for psychiatric patients.