Potential herb-drug interactions in community-dwelling older adults in China: the Shanghai Aging Study.

Abstract

Potential herb-drug interactions (pHDIs) often go unrecognized, and little is known about the prevalence of pHDIs in older adults. This study aimed to investigate the prevalence of pHDIs in community-dwelling older adults in Shanghai and identify patterns and factors associated with pHDIs. Baseline data from the Shanghai Aging Study, which was designed to establish a prospective community-based cohort of older adults in Shanghai, were analyzed regarding pHDIs with Lexi-Interact Online software. Among 1227 participants who used any combination of drug-herb or herb-herb, 43.3% were exposed to at least one pHDI. A total of 1641 different pHDIs were identified among the study samples. Only seven (0.4%) pHDIs were rated as risk category X, indicating that the combinations were contraindicated and should be avoided. Worryingly, 876 (53.4%) pHDIs were rated as risk category D, indicating that significant interactions may occur and therapeutic modification should be considered. Of particular concern is that 99.8% of pHDIs in risk category D involve herbs with anticoagulant/antiplatelet properties. Individuals with stroke (odds ratio [OR] 2.02), hyperlipidemia (OR 1.51) or heart diseases (OR 1.42) and the number of herbs (2.66), number of drugs (OR 1.21), and age (OR 1.02) were significantly associated with the risk of pHDIs. 43.3% of community-dwelling older adults who used any combination of drug-herb or herb-herb was exposed to pHDIs, and more than half of pHDIs were related to herbs with anticoagulant/antiplatelet properties. Awareness of the patterns and high-risk groups of these pHDIs may contribute to increased patient safety.