TY - JOUR A1 - Eidam, Annette A1 - Marji, Julian A1 - Benzinger, Petra A1 - Foerster, Kathrin I. A1 - Burhenne, Jürgen A1 - Czock, David A1 - Stoll, Felicitas A1 - Blank, Antje A1 - Mikus, Gerd A1 - Haefeli, Walter E. A1 - Bauer, Jürgen M. T1 - Frailty as a Marker for the Plasma Concentrations of Direct Oral Anticoagulants in Older Patients: Results of an Exploratory Study T2 - Drugs & Aging N2 - Background: Frailty makes older adults vulnerable to adverse health outcomes and can modify pharmacokinetics and drug exposure. Objective: We aimed to explore the relationship between different frailty assessments and trough plasma concentrations of direct oral anticoagulants in older patients. Methods: The frailty status of adults aged ≥ 70 years receiving regular direct oral anticoagulant medication was assessed by four different instruments: Fried physical phenotype, Rockwood frailty index, Short Physical Performance Battery, and FRAIL scale. The two performance measures “slow gait speed” and “weak grip strength” were used to build a separate score depending on the number of positive criteria (none, one, two). For each participant, a single steady-state direct oral anticoagulant trough plasma concentration was collected, dose-normalized, and its relationship to the various frailty assessments analyzed. Results: Forty-two participants completed the study, with most using apixaban (n = 22). Dose-normalized apixaban trough concentrations were 2.48-fold higher in frail participants (Fried phenotype) than in robust participants (p = 0.009) and correlated positively with Fried physical phenotype (rs = 0.535, p = 0.010) and negatively with Short Physical Performance Battery (rs = − 0.434, p = 0.044). Compared with participants who met none of the criteria “slow gait speed” and “weak grip strength”, apixaban trough concentrations were approximately 1.9-fold higher in participants who were positive for one (p = 0.018) or two (p = 0.013) of these measures. Conclusions: In this exploratory study, higher levels of frailty on performance-based frailty assessments were associated with higher apixaban exposure in older adults. KW - frailty KW - anticoagulation KW - Frailty KW - Antikoagulation Y1 - 2023 UR - https://opus4.kobv.de/opus4-hs-kempten/frontdoor/index/index/docId/1590 SN - 1170-229X SN - 1179-1969 VL - 2023 SP - 1 EP - 12 PB - Springer CY - Berlin ER -