Differential impact of insulin and obesity on cardiovascular risk factors in non-diabetic subjects.
OBJECTIVE
To assess the differential impact of obesity and hyperinsulinaemia on cardiovascular risk factors in non-diabetic, normotensive subjects.


METHODS
Cross-sectional (n = 1897) and 8-year follow-up data (n = 1047) from non-diabetic, normotensive, normolipidaemic men and women (screened in the San Antonio Heart Study) with a body mass index [BMI] in the range 15.2-58.5 kg/m2.


RESULTS
183 of 849 obese subjects (BMI > or = 27 kg/m2 in men, > or = 26 in women) had fasting and post-glucose plasma insulin concentrations superimposable on those of the normoinsulinaemic segment of the non-obese subgroup. Yet, waist/hip ratio (WHR), systolic and diastolic blood pressure, fasting plasma glucose and triglyceride levels were significantly higher, and serum HDL-cholesterol concentrations lower, in the obese than in the non-obese. In the whole sample (n = 1897), both obesity and hyperinsulinaemia were independently associated with higher WHR, arterial blood pressure, fasting and post-load plasma glucose and triglyceride concentrations, and lower HDL-cholesterol levels. This pattern of associations was essentially unaltered after adjustment by WHR. In the subjects re-tested 8 years following the initial screening, the 8-year changes in the level of cardiovascular risk factors were significantly associated with the corresponding changes in both fasting plasma insulin and BMI, independently of one another.


CONCLUSIONS
Although plasma insulin and body weight are closely inter-related variables, they have a separate impact on the cardiovascular risk profile in normal subjects.
Ferrannini
E
E
CNR Institute of Clinical Physiology, University of Pisa, Italy.
Muscelli
E
E
Stern
M P
MP
Haffner
S M
SM
D000328:Adult; D001786:Blood Glucose / Q000378:metabolism; D001794:Blood Pressure; D001824:Body Constitution; D015992:Body Mass Index; D002318:Cardiovascular Diseases / Q000209:etiology*; D008076:Cholesterol, HDL / Q000097:blood; D008078:Cholesterol, LDL / Q000097:blood; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D007328:Insulin / Q000097:blood*; D008297:Male; D009765:Obesity / Q000150:complications*; D012307:Risk Factors; D014280:Triglycerides / Q000097:blood
D001786:Blood Glucose; D008076:Cholesterol, HDL; D008078:Cholesterol, LDL; D007328:Insulin; D014280:Triglycerides