Recombinant human growth hormone treatment in elderly patients undergoing elective total hip replacement

OBJECTIVE Measures to prevent postoperative catabolism may be of greatest benefit in the elderly because of their reduced lean tissue reserve. We examined the effects of recombinant human growth hormone (GH) treatment on body composition and physical performance in elderly patients undergoing elective total hip replacement. METHODS We recruited 33 patients (aged 60-82 years) scheduled for hip replacement. The study was double-blind and placebo-controlled with parallel groups. GH or placebo was administered for 14 weeks preoperatively (target GH dose 0.04 U/kg/day) and 4 weeks postoperatively (with dose doubled for first 2 weeks postoperatively). Serum IGF-I, body composition, mid-thigh muscle cross-sectional area, muscle strength and 4-min walking distance were measured at baseline, 2-3 days preoperatively and 4 weeks postoperatively. RESULTS Mean serum IGF-I doubled during GH treatment. Lean body mass increased preoperatively by an average of 5.2% (representing 1.8 kg) with GH treatment (P < 0.05 vs. placebo), but fell postoperatively by 3% in both groups. Similar changes pre- and postoperatively were seen for mid-thigh muscle cross-sectional area, such that there was no net loss in the GH group but a fall of more than 10% in the placebo group (P < 0.005 vs. GH). There was a trend towards a favourable effect of GH on strength in the majority of muscles tested, but this was significant only for the abductors of the nonoperated hip (P < 0.02), where there was a 7% increase in strength over the whole study compared with a 25% decrease in the placebo group. Four-minute walking distance improved postoperatively by a mean of 26.9 m in the GH group compared with a 19.5 m reduction in the placebo group (P < 0.05). Dose-related side-effects were seen in the majority of patients receiving GH. CONCLUSIONS In elderly patients undergoing total hip replacement, preoperative GH treatment results in improvements in lean body mass and skeletal muscle mass that are sufficient to offset postoperative losses. The treatment may also preserve or improve muscle strength and postoperative walking ability.