Dynamic Balance Metrics Predict Physical Function in Older Adults: Linking Limits of Stability to SPPB Scores

Background Physical function is crucial for the independence of older adults. SPPB (Short Physical Performance Battery) is the main method for subjectively measuring physical function, however, the quantitative assessment methods are still lacking. This study aims to examine the value of Limits of Stability (LOS) in evaluating physical function in older adults. Methods According to SPPB results, 284 older people were split into two groups: those with poor physical function (PPF) and those with good physical function (GPF). LOS was measured using Computer Dynamic Posturography (CDP), which includes endpoint excursion (EPE) and maximal excursion (MXE). The association between LOS and SPPB scores was examined using Spearman correlation analysis and multivariate logistic regression analysis. Results Spearman correlation analysis revealed that the higher EPE and MXE, the better the physical function (P < 0.05). After controlling for age, gender, body BMI index, and age-adjusted charlson comorbidity Index scores, multivariate logistic regression analysis revealed that EPE and MXE had an independent correlation with SPPB (P < 0.05). ROC curves analysis showed that EPE (AUC = 0.73) and MXE (AUC = 0.72) were strong predictors of poor physical function. Conclusions EPE and MXE are independently associated with SPPB scores, suggesting that LOS can quantify older people's physical function, training in movement speed and distance is beneficial for improving physical function.