Short and long-term cardiovascular effects of growth hormone in growth hormone deficient adults.
OBJECTIVE: Since GH substitution is now available for adult GH deficient patients, information on the cardiovascular effects of GH substitution has assumed major clinical interest. We have therefore assessed cardiovascular effects of short and long-term growth hormone substitution in these patients.
PATIENTS AND MEASUREMENTS: Doppler echocardiography was performed in 21 GH deficient patients after 4 months placebo and 4 months GH , in a double blind cross-over study. In an open design study, 13 patients were reinvestigated following 16 months and 9 patients following 38 months of GH . Twenty-one age and sex-matched normal control subjects were also investigated.
RESULTS: Heart rate was increased in placebo treated patients as compared to controls. After 4 months of GH results, heart rate showed a further increase (10%, P < 0.01) and seemed to remain elevated after 16 months of GH . Systolic and diastolic blood pressures were significantly lower in placebo treated patients than in controls, and did not change significantly after GH results. The left ventricular diastolic diameter was reduced in patients as compared to controls, but increased after 4 months GH (P > 0.05) and seemed to increase further during prolonged GH results. Cardiac index was at the same level in controls and in placebo-treated patients, but increased by 20% following GH and remained elevated after 16 and 38 months (P < 0.05) of GH substitution.
CONCLUSION: Following GH substitution in GH deficient adult patients, left ventricular diastolic dimensions increased and seemed to normalize, while heart rate and cardiac output were found to be increased to supranormal levels.