Body mass index and trajectories of the cognition among Chinese middle and old-aged adults

This study aims to investigate the association between trajectories of the cognition and body mass index (BMI) among Chinese middle and old-aged adults. A total of 5693 adults (age 45 +) whose cognitive score is higher than average at the baseline were included from China Health and Retirement Longitudinal Study (CHARLS:2011-2015). Cognitive function was measured by Mini-mental state examination (MMSE) in Chinese version. The Group-based trajectory modeling (GBTM) was adopted to identify the potential heterogeneity of longitudinal changes over the past 5 years and to investigate the relationship between baseline BMI and trajectories of cognitive function. Three trajectories were identified in results: the slow decline (37.92%), the rapid decline (6.71%) and the stable function (55.37%). After controlling for other variables, underweight (BMI < 18.5 kg/m(2)) was associated with the rapid and slow decline trajectories. Obesity (BMI > 28 kg/m(2)) was associated with the slow decline trajectory. High-risk people of cognitive decline can be screened by measuring BMI.

Automated summary

This study investigates the association between trajectories of cognition and body mass index (BMI) among Chinese middle and old-aged adults. Three trajectories were identified: slow decline, rapid decline, and stable function. Underweight was associated with rapid and slow decline trajectories, while obesity was associated with the slow decline trajectory.