Vitale G et al. (2005) Hypertension in acromegaly and in the normal population: prevalence and determinants. Clin Endocrinol 63: 470–476

Noncontrolled, small studies have documented the high incidence of hypertension in patients with acromegaly, in whom chronic excess of growth hormone and insulin-like growth factor 1 (IGF-1) contribute to fluid retention and increased cardiovascular mortality rates. This case–control study by Vitale et al. aimed to determine the prevalence of hypertension in patients with acromegaly, and to evaluate predictive factors for increased systolic and diastolic blood pressures.

In total, 200 patients with acromegaly were compared with 200 control individuals from the same geographic area. Populations were matched for age, sex, BMI, and smoking status. The incidence of hypertension in patients with acromegaly was nearly double that of the control group (46% versus 25%). Although the prevalence of hypertension increased with increasing age in both groups, hypertension developed a decade earlier in the acromegaly group, and was associated with lower systolic, but higher diastolic, blood pressure than that of the hypertensive control group. These differences remained even in subgroups matched for age and sex. The preferential increase in diastolic blood pressure might be explained by the stimulatory effects of excessively high levels of growth hormone and IGF-1 on proliferation of vascular smooth muscle. By contrast, in the control group, higher levels of IGF-1 correlated with lower diastolic blood pressures, even after adjustment for age. This points, perhaps, to a protective role for IGF-1 in the general population.

The authors conclude that the pathogenesis of hypertension in acromegaly differs from that in the general population, and call for further studies.