Poor physical fitness is independently associated with mild cognitive impairment in elderly Koreans

The purpose of this study was to investigate the association between physical fitness and mild cognitive impairment (MCI) in elderly Koreans. This was a cross-sectional study that involved 134 men and 299 women aged 65 to 88 years. Six senior fitness tests were used as independent variables: 30 s chair stand for lower body strength, arm curl for upper body strength, chair-sit-and-reach for lower body flexibility, back scratch for upper body flexibility, 8-ft up-and-go for agility/dynamic balance, and 2-min walk for aerobic endurance. Global cognitive function was assessed using the Korean version of the Mini-Mental State Examination (MMSE). Potential covariates such as age, education levels, blood lipids, and insulin resistance (IR) markers were also assessed. Compared to individuals without MMSE-based MCI, individuals with MMSE-based MCI had poor physical fitness based on the senior fitness test (SFT). There were significant positive trends observed for education level (p=0.001) and MMSE score (p<0.001) across incremental levels of physical fitness in this study population. Individuals with moderate (OR=0.341, p=0.006) and high (OR=0.271, p=0.007) physical fitness based on a composite score of the SFT measures were less likely to have MMSE-based MCI than individuals with low physical fitness (referent, OR=1). The strength of the association between moderate (OR=0.377, p=0.038) or high (OR=0.282, p=0.050) physical fitness and MMSE-based MCI was somewhat attenuated but remained statistically significant even after adjustment for the measured compounding factors. We found that poor physical fitness was independently associated with MMSE-based MCI in elderly Koreans.