Mild cognitive impairment and sedentary behavior: A multinational study

Background: Sedentary behavior (SB) is associated with poor cognitive performance. However, the contribution of sedentary time to risk of mild cognitive impairment (MCI) remains unclear. This study assessed the association of SB with MCI in six low- and middle-income countries. Methods: The Study on Global Ageing and Adult Health (SAGE) survey included 34,129 adults aged ≥50 years [mean (SD) age 62.1 (15.6) years; 51.7% females]. SB was self-reported and expressed as a categorical variable [<8 or ≥8 h per day (high SB)]. The definition of MCI was based on the recommendations of the National Institute on Ageing-Alzheimer's Association. Multivariable logistic regression analysis was conducted to assess the association between SB and MCI. Results: The overall prevalence (95%CI) of MCI and high SB (i.e., ≥8 h/day) were 15.3% (14.4%–16.3%) and 10.1% (9.0%–11.3%), respectively. After adjustment for potential confounders, being sedentary for ≥8 h/day was associated with a 1.56 (95%CI = 1.27–1.91) times higher odds for MCI. A one-hour increase in SB was associated with a 1.08 (95%CI = 1.05–1.11) times higher odds for MCI. Conclusion: Our study results highlight the need to further explore a sedentary lifestyle as a potential risk factor for MCI or subsequent dementia. Longitudinal and intervention studies are warranted to confirm/refute the current findings.