Elevated body mass in National Football League players linked to cognitive impairment and decreased prefrontal cortex and temporal pole activity.

ABSTRACT:
Obesity is a risk factor for neurodegenerative disease and has been shown to adversely affect cognitive function. Professional athletes who participate in sports which expose them to repetitive concussions may be at heightened risk for cognitive impairment. Here, we investigated the effects of body mass as measured by waist to height ratio (WHtR) on regional cerebral blood flow using SPECT imaging in 38 healthy weight (WHtR mean 49.34% ± 2.8; age 58 ± 9.6) and 38 overweight (WHtR mean 58.7% ± 4.7; age 58 ± 13.3) retired NFL football players. After matching for age and position, we used a 2 sample t-test to determine the differences in blood flow in healthy versus overweight subjects. Statistical parametric mapping (SPM) revealed a higher WHtR ratio is associated with decreased blood flow in Brodmann Areas 8, 9, 10 brain regions involved in attention, reasoning and executive function (P<0.05, family-wise error) along with deficits in the temporal pole. Moreover, overweight athletes had significant decreases in attention (P = 0.01326), general cognitive proficiency (P = 0.012; Microcog: Assessment of Cognitive Functioning (MACF)) and memory (P = 0.005; Mild Cognitive Impairment Screen (MCIS)). The association between elevated WHtR percentage and decreased blood flow in the prefrontal cortex and temporal pole may be correlated with the decreased performance on tests of attention and memory. These findings suggest a weight management program may be critical to the health of athletes who have been exposed to mild brain trauma during their careers.