Associations between Sedentary Duration and Cognitive Function in Older Adults: A Longitudinal Study with 2-Year Follow-Up.

OBJECTIVES: This study aimed to investigate the association between different forms of sedentary behavior and cognitive function in Chinese community-dwelling older adults. DESIGN: A longitudinal study with a 2-year follow-up. SETTING AND PARTICIPANTS: Data from 5356 participants at baseline and 956 participants at the follow-up of the Anhui Healthy Longevity Survey (AHLS) were analysed. MEASUREMENTS: Cognitive function was evaluated by the Mini-Mental State Examination (MMSE), and mild cognitive impairment (MCI) was classified according to education-specific criteria. Self-report questionnaires were used to assess the sedentary behavior of the participants. RESULTS: The participants who reported longer screen-watching sedentary duration had higher MMSE scores (1-2 hours: ß=0.758, 95% CI: 0.450, 1.066; > 2 hours: ß=1.240, 95% CI: 0.917, 1.562) and lower likelihoods of MCI (1-2 hours: OR= 0.787, 95% CI: 0.677, 0.914; >2 hours: OR=0.617, 95% CI: 0.524, 0.726). The participants who had played cards (or mahjong) sedentary had higher MMSE scores (ß= 1.132, 95% CI: 0.788, 1.476) and lower likelihoods of MCI (OR=0.572, 95% CI: 0.476, 0.687). However, the participants who reported longer other forms of sedentary duration had lower MMSE scores (1-2 hours: ß=-0.409, 95% CI: -0.735, -0.082; > 2 hours: ß=-1.391, 95% CI: -1.696, -1.087) and higher likelihoods of MCI (1-2 hours: OR=1.271, 95% CI: 1.081, 1.496; > 2 hours: OR=1.632, 95% CI: 1.409, 1.889). No significant association was detected between sedentary duration and MCI incidence. CONCLUSION: Variations in the impact of diverse sedentary behaviors on the cognitive function were detected in Chinese older adults. However, such associations were cross-sectional and longitudinal associations were not found in the current study.