Models for evaluating intrinsic capacity based on different locomotion assessments in the old-old

Abstract Purpose: To compare the World Health Organization (WHO) intrinsic capacity (IC) model with different IC decline models based on various locomotion assessments for consistency and predictive value of adverse health outcomes. Methods: IC was evaluated using the WHO IC model. Locomotion was assessed using the Short Physical Performance Battery (SPPB), five times sit-to-stand test (FTSST), usual gait speed (GS), timed up-and-go test (TUG), and handgrip strength (HG). Different IC models were constructed based on the outcomes of each locomotion item. Cohen's kappa coefficient was used to evaluate consistency. Logistic regression and receiver operating characteristic curves were used to analyse the relationships between IC decline and adverse health outcomes. Results: A total of 173 older residents (85.1±3.5 years) were enrolled. The consistencies (Cohen's kappa coefficient) of the FTSST, GS, TUG, and HG models with the WHO IC model were 0.83, 0.78, 0.75, and 0.43, respectively. After adjusting for age, sex, and comorbidity, IC decline based on the SPPB, FTSST, GS, and TUG models was significantly associated with falls and functional decline (p < 0.01), while IC decline based on the HG model was not. The FTSST, GS, and TUG models had similar predictive values for falls (0.63 vs. 0.65 vs. 0.63) and functional decline (0.63 vs. 0.64 vs. 0.62) when compared with the WHO IC model (area under the curve= 0.65). Conclusions: IC models based on FTSST, GS, and TUG assessments of the locomotion dimension were in good agreement with the WHO IC model.