Oral Presentation ESA-SRB Conference 2015

Introduction The anaerobic energy system initiates all physical activity and subserves many aspects of physical function of daily living. Anaerobic and physical capacities are reduced in GH deficient (GHD) adults (1).

Aim To investigate whether GH improves anaerobic capacity, physical function and quality of life (QoL) in GHD adults.

Method 18 GHD adults were randomized into a 1-month double-blind placebo-controlled crossover GH (0.5mg/day) study followed by a 6-month open phase. Anaerobic capacity was assessed by the Wingate test and aerobic capacity by the VO₂max test. Physical function was assessed by the stair-climb test, chair-stand test and daily step count by pedometry. QoL was assessed by the AGHDA questionnaire. Between and within treatment effects were analyzed by repeated-measures ANOVA and one tailed t-test.

Results GH treatment normalized IGF-I concentration. Stair-climb and chair-stand performance increased significantly during 1-month GH and placebo treatment. Compared to placebo, GH treatment for 1 month did not affect any outcome measure (table). GH treatment for 6 months significantly increased anaerobic power, chair-stand repetitions, daily step count (p=0.07), energy and vitality QoL scores (p=0.07), but not stair-climb duration or VO₂max

Table: Changes in outcome measures after 1 and 6 months of GH replacement 

*p<0.05  compared to 1-month placebo

Summary 1 month of GH replacement was ineffective. 6-months replacement improved Wingate and chair-stand performance, daily step counts and QoL domains but not VO₂max in GHD adults.

Conclusion GH replacement improves anaerobic capacity, physical function and QoL in a time-dependent manner in GHD adults. Improvement in anaerobic but not aerobic energy system is associated with improvement in physical function and related QoL.