Differences in obesity measures and selected comorbidities in former National Football League professional athletes.
OBJECTIVE
To assess the accuracy of body mass index (BMI) as a measure of obesity compared with percent body fat (%BF) directly measured by dual energy x-ray absorptiometry among retired football players.


METHODS
The level of agreement between BMI and %BF as measures of obesity was assessed by sensitivity, specificity, and the kappa statistic among 129 retired football players. Logistic regression was used to investigate the association between obesity and selected comorbidities.


RESULTS
Using BMI 30 kg/m or higher to identify obesity had poor specificity (0.36): 87 of 129 subjects were classified as obese, yet only 13 were truly obese based on %BF. Although BMI did not reliably indicate true %BF-obesity, BMI-obesity was significantly correlated with lineman position (P < 0.0001), years played (P = 0.03), and obstructive sleep apnea (P = 0.0005).


CONCLUSIONS
Percent body fat measured by dual energy x-ray absorptiometry provides a more accurate measure of obesity than does BMI among retired football players.
Division of General Internal Medicine, School of Public Health, University of California, Los Angeles, CA, USA.
Mark H
MH
Hyman
Diana L
DL
Dang
Yihang
Y
Liu
D015502:Absorptiometry, Photon; D000273:Adipose Tissue / Q000000981:diagnostic imaging; D000328:Adult; D056352:Athletes / Q000706:statistics & numerical data*; D015992:Body Mass Index; D015897:Comorbidity; D003920:Diabetes Mellitus / Q000453:epidemiology; D005538:Football / Q000706:statistics & numerical data*; D005764:Gastroesophageal Reflux / Q000453:epidemiology; D006801:Humans; D006973:Hypertension / Q000453:epidemiology; D017379:Hypertrophy, Left Ventricular / Q000453:epidemiology; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000453:epidemiology*; D012179:Retirement / Q000706:statistics & numerical data; D012680:Sensitivity and Specificity; D020181:Sleep Apnea, Obstructive / Q000453:epidemiology