A cross-sectional analysis examined the dose−response association between physical activity and cognitive function in Chinese subjects. A total of 27,651 participants aged 50 to 85 years were recruited from 2003 to 2008 and cognitive function was assessed by the delayed 10-word recall test (DWRT). Information on potential confounders, including demographic and anthropometric characteristics, socioeconomic position, lifestyle, and disease history, was collected by standardized interview and procedures. Most participants were classified as physically active (53.1%), with 42.4% moderately active and 4.5% physically inactive. Significant dose−response relations were found across quintiles of metabolic equivalent value (METs) with DWRT score in participants with or without good self-rated health (all p for trend < 0.001). In participants with poor self-rated heath, those in the fifth quintile of METs compared to the first quintile had a significantly reduced risk of mild cognitive impairment by 28% (p < .01; p for trend = .006). The association between physical activity and DWRT score remained significant after adjustment for depression. The authors concluded that a significant dose−response relationship between physical activity and cognitive function was found and that the association was more pronounced in participants with poor self-rated health. Ann Epidemiol. 2011 Jul 22. PMID: 21784658.
