Exercise capacity and body mass as predictors of mortality among male veterans with type 2 diabetes.
OBJECTIVE
To demonstrate the relation of exercise capacity and BMI to mortality in a population of male veterans with type 2 diabetes.


METHODS
After excluding two underweight patients (BMI <18.5 kg/m2), the study population comprised 831 consecutive patients with type 2 diabetes (mean age 61 +/- 9 years) referred for exercise testing for clinical reasons between 1995 and 2006. Exercise capacity was determined from a maximal exercise test and measured in metabolic equivalents (METs). Patients were classified both according to BMI category (18.5-24.9, 25.0-29.9, and > or =30 kg/m2) and by exercise capacity (<5.0 or > or =5.0 maximal METs). The association among exercise capacity, BMI, other clinical variables, and all-cause mortality was assessed by Cox proportional hazards. Study participants were followed for mortality up to 30 June 2006.


RESULTS
During a mean follow-up of 4.8 +/- 3.0 years, 112 patients died, for an average annual mortality rate of 2.2%. Each 1-MET increase in exercise capacity conferred a 10% survival benefit (hazard ratio 0.90 [95% CI 0.82-0.98]; P = 0.01), but BMI was not significantly associated with mortality. After adjustment for age, ethnicity, examination year, BMI, presence of cardiovascular disease (CVD), and CVD risk factors, diabetic patients achieving <5 maximal METs were 70% more likely to die (1.70 [1.13-2.54]) than those achieving > or =5 maximal METs.


CONCLUSIONS
There was a strong inverse association between exercise capacity and mortality in this cohort of men with documented diabetes, and this relationship was independent of BMI.
McAuley
Paul A
PA
Cardiology Division, VA Palo Alto Health Care System/Stanford University, Palo Alto, California 94304, USA. pamcauley@verizon.net
Myers
Jonathan N
JN
Abella
Joshua P
JP
Tan
Swee Y
SY
Froelicher
Victor F
VF
D000368:Aged; D001794:Blood Pressure; D001835:Body Weight; D015331:Cohort Studies; D016208:Databases, Factual; D003924:Diabetes Mellitus, Type 2 / Q000401:mortality* / Q000503:physiopathology; D015444:Exercise / Q000502:physiology*; D005080:Exercise Test; D005500:Follow-Up Studies; D006339:Heart Rate; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012907:Smoking / Q000453:epidemiology; D016019:Survival Analysis; D013997:Time Factors; D014481:United States; D014728:Veterans