Growth hormone deficiency and replacement in elderly hypopituitary adults

OBJECTIVE Although elderly hypopituitary adults demonstrate an increase in total and central fat compared with age-matched controls and are distinguishable from control subjects in terms of growth hormone (GH) responsiveness on dynamic testing, there are few data available on response to GH replacement, The objective of this study was to compare the baseline characteristics and longitudinal response to GH replacement in patients aged >65 years with that observed in younger patients enrolled in KIMS (Pharmacia and Upjohn International Metabolic Database). KIMS is a physician-managed, open, long-term surveillance study of adult GH-deficient patients receiving GH replacement. Patients were entered and data provided by interested physicians. PATIENTS Baseline characteristics were studied in 109 patients (66 males) aged >65 years commencing GH replacement at time of entry into KIMS and the effects of GH replacement on blood pressure, lipids and quality of life in 64 patients who had completed at least 6 months of GH replacement. Data were compared with baseline data on 863 patients aged <65 years with adult onset GH deficiency, who had not received GH for at least 6 months prior to entry into KIMS, 220 of whom went on to complete >6 months GH therapy in KIMS, RESULTS Blood pressure, cholesterol and LDL cholesterol were positively correlated with age, particularly in females, and older patients had a predictably higher prevalence of diabetes mellitus and history of hypertension. The frequency of previous fractures was increased in females but not in males aged >65 years. Body mass index, waist/hip ratio and quality of life (AGHDA score) was similar in both groups prior to commencement of GH therapy. GH replacement doses were similar in younger and older patients and the percentage of patients with serum IGF-I of > 2SD above the age-related normal mean was not significantly different between the groups (<65 years, 20%; >65 years, 11%), After 6 months of GH replacement significant improvements were evident in waist circumference, waist/hip ratio, diastolic blood pressure, total and LDL cholesterol and AGHDA score in patients aged <65 years. Similar significant reductions in total and LDL cholesterol were evident in patients >65 years. In addition, male patients aged >65 years demonstrated significant reductions in diastolic blood pressure and AGHDA score but no change in waist circumference whereas females aged >65 years demonstrated a trend to reduction in waist circumference and AGHDA score, CONCLUSIONS These data, derived from the largest series of GH-treated hypopituitary patients published to date, confirm similar baseline characteristics and positive benefit from GH replacement in older compared with younger hypopituitary patients particularly in relation to quality of life.