Abstract
Objective Interventions to increase lean body mass pre-operatively and prevent or reduce postoperative catabolism could be of great benefit in elderly patients with reduced lean tissue reserve. This study examined the effects of recombinant human growth hormone (GH) treatment on body composition and function in elderly patients undergoing elective knee replacement for osteoarthritis. Method 32 patients (aged 58-78 years) were studied in this double blind placebo controlled study. GH or placebo was given for 14 weeks preoperatively (target dose 0.1 IU/Kg/day) and for 4 weeks post operatively. Serum IGF-1, IGFBP2, IGFBP3, body composition, mid-thigh muscle cross-sectional area, muscle strength, 4 minute walking distance and quality of life were measured at baseline, one week preoperatively, four weeks postoperatively and twelve weeks postoperatively. Results Following treatment mean serum IGF-1 was raised significantly compared to baseline in the treatment group with a parallel increase in IGFBP3. There were no significant changes in IGFBP2. Lean mass increased preoperatively by an average of 2 Kg with growth hormone treatment (p<0.05 vs placebo). There was a non-significant increase in the mid-thigh muscle cross-sectional area following growth hormone treatment. This increase in lean body mass was not sufficient to overcome the losses associated with postoperative catabolism. Growth hormone showed no significant changes in muscle function pre or postoperatively. Four minute walking distance showed a trend although statistically non-significant in favour of the treatment group with an increase, on average, in the GH group and a reduction, on average, in the Placebo group after 14 weeks of treatment and an increase, on average, in both treatment groups at study termination. The quality of life analysis shows a beneficial trend in the treatment group in keeping with quality of life changes that are seen in growth hormone deficient patients. Dose related side effects were seen in many of the patients receiving growth hormone. Conclusion In patients undergoing total knee replacement for osteoarthritis, pre-operative GH treatment results in increased lean body mass. The treatment may have some positive effects on aspects of function and quality of life. Treatment with GH was not able to offset postoperative catabolic losses or effect physiotherapy milestones or length of inpatient stay.