The obese without cardiometabolic risk factor clustering and the normal weight with cardiometabolic risk factor clustering: prevalence and correlates of 2 phenotypes among the US population (NHANES 1999-2004).
BACKGROUND
The prevalence and correlates of obese individuals who are resistant to the development of the adiposity-associated cardiometabolic abnormalities and normal-weight individuals who display cardiometabolic risk factor clustering are not well known.


METHODS
The prevalence and correlates of combined body mass index (normal weight, < 25.0; overweight, 25.0-29.9; and obese, > or = 30.0 [calculated as weight in kilograms divided by height in meters squared]) and cardiometabolic groups (metabolically healthy, 0 or 1 cardiometabolic abnormalities; and metabolically abnormal, > or = 2 cardiometabolic abnormalities) were assessed in a cross-sectional sample of 5440 participants of the National Health and Nutrition Examination Surveys 1999-2004. Cardiometabolic abnormalities included elevated blood pressure; elevated levels of triglycerides, fasting plasma glucose, and C-reactive protein; elevated homeostasis model assessment of insulin resistance value; and low high-density lipoprotein cholesterol level.


RESULTS
Among US adults 20 years and older, 23.5% (approximately 16.3 million adults) of normal-weight adults were metabolically abnormal, whereas 51.3% (approximately 35.9 million adults) of overweight adults and 31.7% (approximately 19.5 million adults) of obese adults were metabolically healthy. The independent correlates of clustering of cardiometabolic abnormalities among normal-weight individuals were older age, lower physical activity levels, and larger waist circumference. The independent correlates of 0 or 1 cardiometabolic abnormalities among overweight and obese individuals were younger age, non-Hispanic black race/ethnicity, higher physical activity levels, and smaller waist circumference.


CONCLUSIONS
Among US adults, there is a high prevalence of clustering of cardiometabolic abnormalities among normal-weight individuals and a high prevalence of overweight and obese individuals who are metabolically healthy. Further study into the physiologic mechanisms underlying these different phenotypes and their impact on health is needed.
Wildman
Rachel P
RP
Department of Epidemiology and Population Health, Albert Einstein College of Medicine, 1300 Morris Park Ave, Belfer Building, Room 1309, Bronx, NY 10461, USA. rwildman@aecom.yu.edu
Muntner
Paul
P
Reynolds
Kristi
K
McGinn
Aileen P
AP
Rajpathak
Swapnil
S
Wylie-Rosett
Judith
J
Sowers
MaryFran R
MR
D000328:Adult; D000367:Age Factors; D001786:Blood Glucose / Q000032:analysis; D001794:Blood Pressure / Q000502:physiology; D015992:Body Mass Index; D002097:C-Reactive Protein / Q000032:analysis; D008076:Cholesterol, HDL / Q000097:blood; D016000:Cluster Analysis; D003430:Cross-Sectional Studies; D005260:Female; D006306:Health Surveys; D006801:Humans; D007333:Insulin Resistance / Q000502:physiology; D008297:Male; D008875:Middle Aged; D009043:Motor Activity; D009765:Obesity / Q000453:epidemiology*; D050177:Overweight / Q000453:epidemiology; D010641:Phenotype; D044469:Racial Groups; D012307:Risk Factors; D014280:Triglycerides / Q000097:blood; D014481:United States / Q000453:epidemiology; D049629:Waist-Hip Ratio
D001786:Blood Glucose; D008076:Cholesterol, HDL; D014280:Triglycerides; D002097:C-Reactive Protein