Physical frailty is related to oxidative stress through thiol/disulfide homeostasis parameters

To evaluate relationship between frailty and oxidative stress through thiol/disulfide homeostasis parameters [Native thiol (NT), total thiol (TT), and disulfide levels (D), disulfide–native thiol (D/NT), disulfide–total thiol (D/TT), native thiol–total thiol (NT/TT) ratios, and ischemia-modified albumin levels (IMA)].

In total, 139 community-dwelling older adults were included. The frailty status, defined by the FRIED frailty index (FFI) and Clinical Frailty Scale (CFS), and comprehensive geriatric assessment results compared with thiol/disulfide homeostasis parameters and ischemia-modified albumin levels.

NT and TT levels were significantly lower in the frail group (respectively; p = 0.014, p = 0.020). The FFI scores were correlated with the levels of NT, TT, D/NT, D/TT, and NT/TT (respectively; r = − 0.25, r = − 0.24, r = 0.17, r = 0.17, r = − 0.17). The significant correlation could not be retained with the CFS scores. In ROC analysis, the AUC for NT was calculated as 0.639 in diagnosing frailty according to the FFI (95% CI 0.542–0.737), AUC was 0.638 for TT (95% CI 0.540–0.735), and AUC was 0.610 for NT/TT (95% CI 0.511–0.780). The AUC was calculated as 0.610 for both D/NT and D/TT in diagnosing physical frailty (95% CI 0.511–0.708).

Thiol/disulfide homeostasis parameters can be a potential biomarker in diagnosing physical frailty. However, further studies are needed for diagnosing frailty defined with cumulative deficit models.