Benefit of Growth Hormone Replacement in Adults Older than 60 Years

Kristin Arp, Christian Schwahn, Nele Friedrich, Thomas Kohlmann, Jörn Moock, Maria Koltowska-Häggström, Matthias Nauck, Michael Buchfelder, Henri Wallaschofski, Christin Spielhagen

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Institute of Clinical Chemistry and Laboratory Medicine, University Medicine Greifswald, Greifswald, Germany.

DOI: 10.4236/ojemd.2013.33024                

Abstract

Objective: Benefits of replacement therapy in growth hormone deficiency (GHD) are well documented in younger and middle-aged patients. The aim of our investigation was to prove the benefit of GH replacement for patients older than 60 years especially in terms of health-related quality of life (HRQoL) of age as well. Design: Data of 743 consecutively recruited patients (394 men, 349 women) with GHD aged 20 - 49 (n = 606) and 60 - 69 (n = 137) years enrolled from KIMS Germany (Pfizer International Metabolic Database) were compared. Treatment effects over the 12 months dose-finding and the subsequent phase up to three years were analysed using mixed models. Serum insulin-like growth factor I (IGF-I), fasting blood glucose, fasting serum total cholesterol and low-density lipoprotein cholesterol (LDL-C) as well as body mass index (BMI) at baseline and at last visit were studied. HRQoL was assessed using the Quality of Life-Assessment of Growth Hormone Deficiency in Adults (QoL-AGHDA). Results: For both age groups and genders the IGF-I level and standardized IGF-I increased over the dose-finding phase. In women, the overall QoL-AGHDA score at the baseline examination was 8.7 (95% CI: 7.7 - 9.7) and decreased to 6.3 (95% CI: 5.1 - 7.6) at the end of the dose-finding phase (p < 0.001). In men, the corresponding values were 8.8 (95% CI: 7.8 - 9.8) and 6.4 (95% CI: 5.1 - 7.6; p < 0.001) without differences between the age groups. The therapy benefit for elderly was supported by the non-impairment after the dose-finding phase. In total cholesterol, LDL-C and fasting blood glucose, no significant changes were detected, whereas an increase in BMI did not differ between age groups. Conclusion: We could show positive effects of GH replacement on HRQoL in patients older than 60 years of age. Therefore, GH replacement should be considered in elderly GHD adults without difference compared to younger age groups.

Keywords

Growth Hormone Deficiency; Quality of Life; Growth Hormone; IGF-I

Conflicts of Interest

The authors declare no conflicts of interest.

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