Elderly people with hypothalamic-pituitary disease and growth hormone deficiency: lipid profiles, body composition and quality of life compared with control subjects.

OBJECTIVE

In healthy adults the secretion of growth hormone (GH) and insulin-like growth factor 1 (IGF-1) declines with ageing and body composition alters, particularly with an increase in total body fat. In elderly people, hypothalamic-pituitary disease can cause GH deficiency (GHD), compared with age matched controls. This study aimed to clarify whether GHD in the elderly is associated with differences in body composition, circulating lipid levels and quality of life (QOL) compared with control subjects.

SUBJECTS

Twenty-seven elderly patients (14 males, mean age 71 years, range 65-83) with hypothalamic-pituitary disorders (23 pituitary tumours) and GHD (mean (SD) peak stimulated GH response 1.6 mIU/l (1.03) range 0.6-5) were studied. Twenty-five patients had been treated surgically (six cranial surgery, 19 transsphenoidal) and eight patients had received external cranial irradiation. Twenty-seven control subjects (14 males, mean age 72 years, range 65-86) were also studied.

METHODS

Weight, body mass index (BMI), total fat mass (FM, bioelectrical impedance), waist to hip ratio (WHR), serum IGF-1, fasting blood glucose and lipid profile were measured. QOL was assessed in both groups using five interviewer administered self-rating questionnaires: The Nottingham Health Profile, Short-Form 36, Hospital Anxiety and Depression Scale, Mental Fatigue Questionnaire and Life Fulfilment Scale. The GHD group also completed the Disease Impact Scale.

RESULTS

The data (mean (SD)) from males and females were analyzed separately. The male patients had a higher BMI than controls, 28.9(4.5) vs. 25.2(2.3) kg/m2 (P = 0.01) but the BMI in the female patients and controls was similar. In the female patients compared with the controls, FM was higher 39. 4(6) vs. 33.1(8.3) % (P = 0.02), WHR was also higher 0.9(0.08) vs. 0. 83(0.09) (P = 0.03) and serum IGF-1 levels were lower 10.8(6.4) vs. 18.2(6.5) nmol/l (P = 0.01). However, in the male patients, FM, WHR and IGF-1 levels were similar to the controls. Fasting blood glucose was similar in both male and female patients and the controls. Two female patients and one male control subject were taking lipid-lowering agents and were therefore excluded from the analysis of lipid profiles. Total cholesterol, triglyceride, LDL cholesterol, HDL cholesterol and total cholesterol/HDL cholesterol ratio were not significantly different for both male and female patients compared with the controls. The 27 patients with GHD reported significantly less energy (P < 0.05), mobility (P < 0.05) and personal life fulfillment (P < 0.01) than the 27 controls. There were significantly more problems with emotional reaction (P < 0.01), social isolation (P < 0.05) and mental fatigue (P < 0.05). Additionally the GHD group reported more impairment in areas of social functioning (P < 0.05), general health (P < 0.05) and mental health (P < 0.05). The GHD group reported a modest degree of disease impact (mean score of 14.1). There were no significant differences in the domains of material life fulfillment, pain, sleep, physical functioning, vitality, anxiety, depression, self-esteem or role physical functioning compared with the controls.

CONCLUSION

Compared with control subjects, the elderly female patients with hypothalamic-pituitary disease and GHD had a significantly higher total fat mass, with the WHR indicating a more central fat distribution and lower female serum IGF-1 levels. In contrast, elderly male patients had similar total fat mass, WHR and IGF-1 levels compared to the controls. There were no significant differences in the lipid profiles between male or female patients compared to controls. However, many of the male patients were receiving androgen replacement which might have influenced these results. Low HDL cholesterol concentrations are probably a better predictor of future cardiovascular disease than raised LDL cholesterol levels in the elderly population and these were similar in patients and controls for both