Midlife physical activity engagement is associated with later-life brain health.

The relationship between midlife physical activity (PA), and cognition and brain health in later life is poorly understood with conflicting results from previous research. Investigating the contribution of midlife PA to later-life cognition and brain health in high-risk populations will propel the development of health guidance for those most in need. The current study examined the association between midlife PA engagement and later-life cognition, grey matter characteristics and resting-state functional connectivity in older individuals at high-risk for Alzheimer's disease. The association between midlife PA and later-life cognitive function was not significant but was moderated by later-life PA. Meanwhile, greater midlife moderate-to-vigorous PA was associated with greater grey matter surface area in the left middle frontal gyrus. Moreover, greater midlife total PA was associated with diminished functional connectivity between bilateral middle frontal gyri and middle cingulum, supplementary motor areas, and greater functional connectivity between bilateral hippocampi and right cerebellum, Crus II. These results indicate the potentially independent contribution of midlife PA to later-life brain health.

Does sleep-disordered breathing add to impairments in academic performance and brain structure usually observed in children with overweight/obesity?

Approximately 4-11% of children suffer from sleep-disordered breathing (SDB), and children with obesity are at increased risk. Both obesity and SDB have been separately associated with poorer brain health, yet whether SDB severity affects brain health in children with obesity remains unanswered. This study aimed to examine associations of SDB severity with academic performance and brain structure (i.e., total brain and gray and white matter volumes and gray matter volume in the hippocampus) in children with overweight/obesity. One hundred nine children aged 8-12 years with overweight/obesity were included. SDB severity and its subscales (i.e., snoring, daytime sleepiness, and inattention/hyperactivity) were evaluated via the Pediatric Sleep Questionnaire (PSQ), and academic performance was evaluated with the Woodcock-Muñoz standardized test and school grades. Brain structure was assessed by magnetic resonance imaging. SDB severity was not associated with academic performance measured by the standardized test (all |ß|> 0.160, P > 0.076), yet it was associated with the school grade point average (ß = -0.226, P = 0.007) and natural and social science grades (ß = -0.269, P = 0.024). Intention/hyperactivity seemed to drive these associations. No associations were found between SDB severity and the remaining school grades (all ß < -0.188, P > 0.065) or brain volumes (all P > 0.05). CONCLUSION: Our study shows that SDB severity was associated with lower school grades, yet it was not associated with the standardized measurement of academic performance or with brain volumes in children with overweight/obesity. SDB severity may add to academic problems in children beyond the effects contributed by overweight/obesity status alone. WHAT IS KNOWN: • Sleep-disordered breathing (SDB) may affect brain structure and academic performance in children. • Children with overweight/obesity are at higher risk for the development of SDB, yet the comorbid obesity-SDB relationship with brain health has not been investigated thus far. WHAT IS NEW: • To our knowledge, this is the first study examining the associations of comorbid obesity-SDB severity with brain volumes and academic performance in children. • SDB symptoms may adversely affect academic performance at school in children with overweight/obesity, beyond the effects of weight status alone.