Insulin sensitivity in obese normotensive adults: influence of family history of hypertension.
OBJECTIVE
To evaluate the influence of family history of hypertension on insulin sensitivity in obese normotensive adults, comparing them with lean subjects.


METHODS
136 normotensives (N)(mean 24 h blood pressure < 130/80 mmHg; age range 35-45 y): 32 lean (body mass index, BMI < or = 25 kg/m2) N with normotensive parents (F-), 37 lean N with one or two parents hypertensive (F+), 32 obese (BMI > or = 30 kg/m2) NF- and, 35 obese NF+.


METHODS
24 h ambulatory blood pressure monitoring; glucose, insulin and C-peptide before and 30, 60, 90 and 120 min after an oral glucose load; index of insulin peripheral activity (Ia: 10(4)/insulin x glucose values at glucose peak); fasting insulin/C-peptide ratio (I/Cp).


RESULTS
The four groups were comparable for age, gender and blood pressure values throughout the 24 h. Glucose, fasting and during test, and I/Cp were similar among the four groups; insulin and C-peptide, fasting and stimulated, were significantly higher and Ia lower in obese N than in lean N; at similar BMI, insulin and C-peptide were significantly higher and Ia lower, in F+ than in F-. The correlation between insulin and BMI was significantly closer in F- than in F+.


CONCLUSIONS
Family history of hypertension appears to be significantly associated with insulin sensitivity in both lean and obese normotensive adults; moreover, overweight and a genetic predisposition to hypertension may have additive adverse effects on insulin sensitivity in normotensive adult subjects.
Department of Clinical and Biological Sciences, II Faculty of Medicine, University of Pavia, Varese, Italy.
A M
AM
Grandi
G
G
Gaudio
A
A
Fachinetti
E
E
Piantanida
P
P
Zanzi
L
L
Ceriani
L
L
Guasti
A
A
Venco
D000328:Adult; D001786:Blood Glucose / Q000378:metabolism; D018660:Blood Pressure Monitoring, Ambulatory; D001824:Body Constitution; D015992:Body Mass Index; D002096:C-Peptide / Q000097:blood; D005260:Female; D005951:Glucose Tolerance Test; D006801:Humans; D006973:Hypertension / Q000235:genetics*; D007328:Insulin / Q000097:blood*; D007333:Insulin Resistance / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000503:physiopathology*
D001786:Blood Glucose; D002096:C-Peptide; D007328:Insulin