Insulin resistance, exercise capacity and body composition in subjects with two hypertensive parents.
OBJECTIVE
To study insulin resistance in subjects with strong genetic predisposition to essential hypertension, compared with non-disposed subjects.


METHODS
Thirty normotensive subjects aged 18-35 years whose parents both had essential hypertension, and 30 age- and sex matched subjects whose parents were both normotensive, were studied. Subjects or parents with diabetes and morbid obesity were excluded.


METHODS
The study comprised (1) a frequent sampling oral glucose tolerance test; (2) an isoglycemic hyperinsulinemic clamp study; (3) an analysis of body composition by dual-energy X-ray absorptiometry; (4) an exercise test with gas exchange analysis; and (5) investigation of composition of usual diet by diet registration for 5 days.


RESULTS
The 24-h diastolic blood pressure was higher in subjects predisposed to hypertension compared with the controls: 78.1 versus 74.0 mmHg (confidence interval for the difference between the means; -0.5; -7.9), but the insulin sensitivity index was similar: 312 versus 362 I(2) min(-1) pmol(-1) kg(-1) (28; -129). The two groups were similar in terms of body composition, exercise capacity and composition of usual diet. Resting and 24-h diastolic blood pressures were correlated to abdominal fat mass but not to insulin sensitivity.


CONCLUSIONS
Subjects with a strong genetic predisposition to essential hypertension had increased diastolic blood pressure compared with subjects with normotensive parents, but they were not insulin resistant. This may be due to the subjects being highly selected as to confounding factors. The increased blood pressure in the hypertension prone subjects could not be attributed to differences in body composition, exercise capacity or dietary habits.
Andersen
U B
UB
Department of Clinical Physiology and Nuclear Medicine, Hvidovre Hospital, Denmark. www.uandersen@iname.com
Dige-Petersen
H
H
Ibsen
H
H
Skøtt
P
P
Bruun
N E
NE
Vestergaard
H
H
Christiansen
C
C
D015502:Absorptiometry, Photon; D000293:Adolescent; D000328:Adult; D001786:Blood Glucose; D001794:Blood Pressure / Q000502:physiology; D001823:Body Composition / Q000235:genetics / Q000502:physiology*; D005080:Exercise Test; D017079:Exercise Tolerance / Q000235:genetics / Q000502:physiology*; D005260:Female; D020022:Genetic Predisposition to Disease; D005951:Glucose Tolerance Test; D006801:Humans; D006973:Hypertension / Q000235:genetics* / Q000503:physiopathology; D007328:Insulin / Q000097:blood; D007333:Insulin Resistance / Q000235:genetics* / Q000502:physiology*; D008297:Male; D010290:Parents; D012907:Smoking
D001786:Blood Glucose; D007328:Insulin