Obesity paradox and cardiorespiratory fitness in 12,417 male veterans aged 40 to 70 years.
OBJECTIVE
To evaluate the influence of cardiorespiratory fitness (fitness) on the obesity paradox in middle-aged men with known or suspected coronary artery disease.


METHODS
This study consists of 12,417 men aged 40 to 70 years (44% African American) who were referred for exercise testing at the Veterans Affairs Medical Centers in Washington, DC, or Palo Alto, CA (between January 1, 1983, and June 30, 2007). Fitness was quantified as metabolic equivalents achieved during a maximal exercise test and was categorized for analysis as low, moderate, and high (defined as <5, 5-10, and >10 metabolic equivalents, respectively). Adiposity was defined by body mass index (BMI) according to standard clinical guidelines. Separate and combined associations of fitness and adiposity with all-cause mortality were assessed by Cox proportional hazards analyses.


RESULTS
We recorded 2801 deaths during a mean+/-SD follow-up of 7.7+/-5.3 years. Multivariate hazard ratios (95% confidence interval) for all-cause mortality, with normal weight (BMI, 18.5-24.9 kg/m2) used as the reference group, were 1.9 (1.5-2.3), 0.7 (0.7-0.8), 0.7 (0.6-0.7), and 1.0 (0.8-1.1) for BMIs of less than 18.5, 25.0 to 29.9, 30.0 to 34.9, and 35.0 or more kg/m2, respectively. Compared with highly fit normal-weight men, underweight men with low fitness had the highest (4.5 [3.1-6.6]) and highly fit overweight men the lowest (0.4 [0.3-0.6]) mortality risk of any subgroup. Overweight and obese men with moderate fitness had mortality rates similar to those of the highly fit normal-weight reference group.


CONCLUSIONS
Fitness altered the obesity paradox. Overweight and obese men had increased longevity only if they registered high fitness.
McAuley
Paul A
PA
Department of Human Performance and Sport Sciences, Winston-Salem State University, 601 S Martin Luther King Jr Dr, Anderson C 24-E, Winston-Salem, NC 27110, USA. mcauleypa@wssu.edu
Kokkinos
Peter F
PF
Oliveira
Ricardo B
RB
Emerson
Brian T
BT
Myers
Jonathan N
JN
D000328:Adult; D000368:Aged; D015992:Body Mass Index; D002140:California / Q000453:epidemiology; D002318:Cardiovascular Diseases / Q000209:etiology / Q000401:mortality; D002423:Cause of Death; D004219:District of Columbia / Q000453:epidemiology; D005080:Exercise Test; D006801:Humans; D008297:Male; D055686:Metabolic Equivalent; D008875:Middle Aged; D015999:Multivariate Analysis; D009765:Obesity / Q000150:complications / Q000175:diagnosis / Q000401:mortality*; D010809:Physical Fitness; D016016:Proportional Hazards Models; D011446:Prospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D013851:Thinness / Q000150:complications / Q000175:diagnosis / Q000401:mortality*; D014728:Veterans / Q000706:statistics & numerical data