Prevalence of QT-Prolonging Drug-Drug Interactions in Psychiatry: A Systematic Review and Meta Analysis.

Drug-drug interactions (DDIs) are considered an emerging threat to the patients if undetected. DDIs can prolong QT interval, leading to fatal ventricular arrhythmia. Antipsychotics and antidepressants prescribed commonly to psychiatric patients have the propensity to prolong QT interval and can precipitate Torsades de pointes (TdP). This review aimed to summarize the prevalence of QT interval prolonging DDIs in psychiatric patients. This meta-analysis was carried out following the MOOSE (Meta-analysis of Observational Studies in Epidemiology) statement. Databases like Pubmed/MEDLINE, Google Scholar and Research gate were scanned for English language papers. Indexed terms from Medical Subject (MeSH) and other search terms for "QT prolongation", "Drug interactions", and "Psychiatry" were used to identify the articles. All published articles available until the day of the collection were considered. Outcome measures were analyzed with meta package in R language. A total of 5 studies were eligible for inclusion. From the included studies, QT-prolonging DDIs were found in 14806 patients out of 30122 patients. The prevalence of QT-prolonging DDIs in psychiatric patients was found to be 42% (95% confidence interval: 21%, 66%). The factors associated with potential drug-drug interactions were related to patient characteristics such as polypharmacy, age and comorbid disease. This review concluded that psychiatric patients were prescribed the drugs/drug combinations which can prolong QT interval and can cause adverse effects on the cardiovascular system. Hence, it is important to implement precautionary safety interventions, be vigilant and prevent QT prolongation and adverse cardiac effects in clinical practice.