biostudies-literatureGuo SNational Natural Science Foundation of China3173https://www.ebi.ac.uk/biostudies/studies/S-EPMC12487511biostudies-literatureUnknown25(1)<h4>Background</h4>Body mass index (BMI) affects cognitive health throughout life. BMI variability has emerged as a promising indicator for tracking longitudinal changes in BMI. The association of BMI variability with cognitive impairment remains unclear.<h4>Objective</h4>This study investigated the relationship between BMI variability and cognitive outcomes across age groups defined by a 50-year threshold.<h4>Methods</h4>The current study enrolled 1474 participants (> 18 years) from the China Suboptimal Health Cohort Study (COCAS). Various metrics, including the coefficient of variation (CV), standard deviation (SD), variability independent of the mean (VIM), and average real variability (ARV), were used to measure BMI variability. The main clinical outcome was the incidence of cognitive BMC public healthVisit-to-visit body mass index variability in relation to longitudinal cognitive changes in Chinese adults: a retrospective cohort study.PMC1248751181972144Liu YZhang YWang DGuo SChen XfalseVisit-to-visit body mass index variability in relation to longitudinal cognitive changes in Chinese adults: a retrospective cohort study.<h4>Background</h4>Body mass index (BMI) affects cognitive health throughout life. BMI variability has emerged as a promising indicator for tracking longitudinal changes in BMI. The association of BMI variability with cognitive impairment remains unclear.<h4>Objective</h4>This study investigated the relationship between BMI variability and cognitive outcomes across age groups defined by a 50-year threshold.<h4>Methods</h4>The current study enrolled 1474 participants (> 18 years) from the China Suboptimal Health Cohort Study (COCAS). Various metrics, including the coefficient of variation (CV), standard deviation (SD), variability independent of the mean (VIM), and average real variability (ARV), were used to measure BMI variability. The main clinical outcome was the incidence of cognitive 2025-01-01T00:00:00Z2025 Sep2026-06-06T13:34:05.712Z2026-05-31T03:07:52.99ZS-EPMC124875114102956810.1186/s12889-025-24243-5