Patient-reported physical health and handgrip strength for identifying reduced functional exercise capacity in older adults with ischaemic heart disease

Background Brief assessments may help identify reduced functional exercise capacity when walking tests are not immediately feasible. However, the comparative performance of patient-reported physical health and muscle strength remains unclear. This study compared baseline 12-Item Short Form Health Survey Physical Component Summary (SF-12 PCS), handgrip strength (HGS), and their combination for identifying reduced functional exercise capacity at 3 months in older adults with ischaemic heart disease.Methods This secondary analysis included participants with complete baseline SF-12 PCS, HGS, sex, and 3-month six-minute walk distance (6MWD) data. Reduced functional exercise capacity was defined as 6MWD <350 m. Discrimination was assessed using sex-adjusted logistic regression models and receiver operating characteristic analysis. Exploratory cut-offs were determined using the Youden index.Results Among 350 participants, 57 (16.3%) had reduced functional exercise capacity. SF-12 PCS and HGS showed comparable discrimination (AUC 0.739 and 0.743, respectively), while the combined model yielded the highest AUC (0.777; 95% CI 0.715–0.839), with no significant pairwise differences. Exploratory cut-offs were ≤40.25 points for SF-12 PCS and ≤35.38 kg for men and ≤18.14 kg for women for HGS. In the comorbidity-adjusted model, higher SF-12 PCS (OR 0.776, 95% CI 0.657–0.916) and HGS (OR 0.736, 95% CI 0.605–0.897) were associated with lower odds of reduced functional exercise capacity.Conclusions SF-12 PCS and HGS showed comparable discrimination, with no significant incremental benefit from their combination. These brief assessments may support initial physiotherapy evaluation when the six-minute walk test is not immediately feasible but should complement direct assessment. The exploratory cut-offs require external validation.