Impaired fasting glucose and body mass index as determinants of mortality in ALLHAT: is the obesity paradox real?
Emerging literature suggests that obesity may be "protective" against mortality and cardiovascular outcomes, while dysglycemia may worsen outcomes regardless of obesity. The authors measured the association of weight, smoking, and glycemia with mortality in the Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial (ALLHAT). Among 5423 ALLHAT participants without established diabetes or cardiovascular disease, 3980 (73%) had normal fasting glucose and 1443 (27%) had impaired fasting glucose (IFG) levels at study entry. After a median of 4.9 years follow-up, 554 (10%) had died (37% cardiovascular). IFG was associated with higher all-cause mortality (adjusted hazard ratio [HR], 1.23; 95% confidence interval [CI], 1.02-1.50), while obesity was associated with lower all-cause mortality (adjusted HR, 0.76; 95% CI, 0.60-0.96). However, after excluding underweight individuals (body mass index [BMI] <22 kg/m(2) ) and smokers, neither obesity nor IFG was associated with all-cause mortality [corrected]. Although obesity appeared protective against mortality, this association was not significant in never-smokers or after exclusion of BMI <22 kg/m(2) . The obesity paradox may result from confounding by a sicker, underweight referent population and smoking.
Cardiology Division, Department of Medicine, Massachusetts General Hospital, Boston, MA.
Ravi V
RV
Shah
Siddique A
SA
Abbasi
José-Miguel
JM
Yamal
Barry R
BR
Davis
Joshua
J
Barzilay
Paula T
PT
Einhorn
Alison B
AB
Goldfine
Allison
A
Goldfine
D000368:Aged; D000959:Antihypertensive Agents / Q000627:therapeutic use*; D001786:Blood Glucose / Q000378:metabolism*; D015992:Body Mass Index; D002423:Cause of Death / Q000639:trends; D004311:Double-Blind Method; D005215:Fasting / Q000097:blood*; D005260:Female; D006801:Humans; D006973:Hypertension / Q000097:blood / Q000188:drug therapy* / Q000401:mortality; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000097:blood* / Q000401:mortality / Q000503:physiopathology; D011379:Prognosis; D015996:Survival Rate / Q000639:trends; D014481:United States / Q000453:epidemiology
D000959:Antihypertensive Agents; D001786:Blood Glucose