Association between insulin resistance and objective measurement of physical activity in community-dwelling older adults without diabetes mellitus

Aims: The main objective of this study was to determine the association between objectively measured physical activity (PA) and cardiometabolic risk factors, particularly insulin resistance (IR), in Japanese community-dwelling older adults without diabetes mellitus. Methods: Daily PA was measured by accelerometers in 388 community-dwelling older adults. IR was determined using homeostasis model assessment of insulin resistance (HOMA-IR). Regression analyses adjusted by age and sex were performed to determine the association of light-intensity PA (LPA), moderate-to-vigorous PA (MVPA), or total steps per day with cardiometabolic risk factors. Then, multiple regression analysis was performed with HOMA-IR as an independent variable and those factors with p < 10% in the regression analysis as explanatory variables. Results: Objectively measured LPA was negatively associated with systolic blood pressure, diastolic blood pressure, waist circumference, body mass index, and triglyceride (TG) and positively associated with high-density lipoprotein cholesterol (HDL-C). LPA was also negatively associated with IR. Total steps per day also had significant association with IR. MVPA was associated with TG, HDL-C, and IR. Multiple regression analysis showed that the association between LPA and IR was independent of other covariates, whereas that between MVPA and IR was lost after adjustment for other covariates. Conclusion: IR was associated with LPA or total steps, but not with MVPA, in community-dwelling older adults without diabetes mellitus.