Polypharmacy-related Orthostatic Intolerance Syndrome in Community-dwelling Older Adults

Objective: Polypharmacy (PP) is associated with various adverse outcomes in older adults. Although few studies have shown an association between PP and orthostatic blood pressure changes (OBPCs), its relationship with orthostatic intolerance syndrome (OIS), which describes a group of signs and symptoms triggered by standing up straight with or without OBPCs, is not known. Therefore, we assessed the association between PP and OIS in the geriatric population. Materials and Methods: Ninety-nine geriatric outpatients were enrolled in the study. In addition to comprehensive geriatric assessment, frailty evaluation (modified fried frailty index), OBPC evaluations [active standing test (AST)], and OIS questioning both experienced in the last three months (self-reported OIS) and symptoms emerged during the AST were performed. PP was defined as using >4 drugs. Results: The participants' median age was 74 and ranged from 69.5 to 79.0 years, and 66.7% (n=66) of them were female. Patients were split into Non-OIS and OIS groups based on self-reported OIS, with 51 (51.5%) and 48 (48.5%) patients in each group, respectively. The frequency of PP was higher in the OIS group (p<0.05). In the regression analysis, OIS was significantly related to PP independent of age, sex, malnutrition, and frailty (odds ratio: 0.353, 95% confidence interval: 0.13-0.92, p=0.033). In addition, the number of drugs used was correlated with the total number of OIS symptoms (r=0.204, p=0.042). Conclusion: This is the first study to show the link between PP and OIS. Further research is required to verify our results.