Differential effects of obesity and hypertension on brain structure and cognitive ability: A subgroup analysis from nested study.

Background: Obesity and hypertension are widespread health issues associated with changes in brain structure and cognitive function, especially in individuals who lead sedentary lifestyles. This research examines the connections between obesity, high blood pressure, brain structure, and cognitive abilities in people who lead a sedentary lifestyle.

Materials and methods: The study involved 90 individuals aged between 18 and 35 years, who were categorized into three groups: control (n = 30), obese (n = 30), and hypertensive (n = 30). The researchers used magnetic resonance imaging (MRI) scans to examine the brain's structure, specifically analyzing the volume of different regions. The researchers assessed cognitive function using the flanker task to measure selective attention and the n-back task to evaluate working memory. Statistical analysis involved the use of one-way analysis of variance (ANOVA) and Games-Howell post-hoc tests.

Results: The findings revealed notable variations in the volume of the left parahippocampal gyrus (lPHG) among the different groups, with the control group exhibiting the highest volume, followed by the obese group, and finally the hypertensive group. The cognitive performance varied greatly among the groups in both the flanker and n-back tasks, with a significant difference observed in all measures (P and lt;.001). The group with high blood pressure showed the lowest performance, followed by the group with obesity, with the control group performing the best.

Conclusion: Our findings reveal a gradient of cognitive impairment and reduced lPHG volume in sedentary individuals, with hypertension showing more pronounced effects than obesity alone. These findings underscore the importance of considering the cognitive effects of obesity and hypertension in individuals who lead sedentary lifestyles, underscoring the necessity for comprehensive care strategies that address both physical and cognitive dimensions of these conditions.