Prospective randomised treatment with recombinant human growth hormone in cystic fibrosis. A multicenter, randomized, double-blind, placebo-controlled trial to evaluate the metabolic and respiratory effects of growth hormone in children with cystic fibrosis. Lack of effects of recombinant growth hormone on muscle function in patients requiring prolonged mechanical ventilation: a prospective, randomized, controlled study. Effect of growth hormone on exercise tolerance in children with cystic fibrosis.
To evaluate the efficacy and safety of treatment with recombinant growth hormone (rGH) in patients with cystic fibrosis (CF).
                Twenty patients with CF (aged 10-23 years) were randomised to age and sex matched treatment and control groups. The treatment group received daily subcutaneous injections of 1 IU/kg/wk rGH for 12 months. Pulmonary function (forced expiratory volume in one second (FEV1) and airway resistance), exercise capacity measured with a bicycle ergometer, body composition (dual energy x ray absorptiometry), and weight were assessed at the beginning of the study and after 6 and 12 months.
                rGH treatment did not improve weight and pulmonary function, but lean body mass increased significantly in the treatment group. Exercise capacity increased in the treatment group from 143 (16) W (mean (SD)) to 164 (19) W after 12 months of rGH treatment.
                Treatment of CF patients with rGH for one year improved the exercise capacity significantly but not pulmonary function. The improved exercise capacity needs confirmation in a larger population before such an expensive treatment is justified. Positive effects of growth hormone therapy on growth, nutritional status, and lung function have been observed in patients with cystic fibrosis, but the current evidence is based on unblinded studies that involved a small number of patients. This trial was designed as a multicenter, randomized, placebo-controlled, double-blind study to assess the efficacy and safety of 2 dosages of growth hormone in cystic fibrosis.
                Sixty-three dystrophic patients with cystic fibrosis were randomly assigned for 24 weeks to 1 of 3 treatment arms: growth hormone dosage of 0.11 IU/kg body weight per day, growth hormone dosage of 0.21 IU/kg body weight per day, or placebo. The 24-week double-blind period was followed by an open treatment period of 24 weeks. The primary outcome measure was the change in forced expiratory volume in 1 second in percentage predicted from baseline. Secondary outcome measures were changes in height, weight, and exercise tolerance.
                Height, growth velocity, and growth factors (insulin-like growth factor 1 and insulin-like growth factor-binding protein 3) increased significantly in both treatment groups, whereas weight gain did not differ between the growth hormone groups and placebo. A trend toward improvement in absolute forced vital capacity was observed in patients who received the higher growth hormone dosage, whereas forced expiratory volume in 1 second did not change significantly with growth hormone treatment. Maximal oxygen uptake during peak exercise increased significantly in treated patients. There were no significant differences in the frequency or severity of adverse effects or in the incidence of abnormalities in glucose metabolism.
                These data suggest that in the group investigated, growth hormone therapy was well tolerated and had positive metabolic effects but did not result in short-term improvement of lung function in patients with cystic fibrosis. To evaluate the benefit of recombinant human growth hormone administration on muscle strength and duration of weaning in critically ill patients undergoing prolonged mechanical ventilation.
                Prospective, randomized, controlled, single-blind study.
                Intensive care unit. Patients: Twenty patients requiring > or = 7 days of mechanical ventilation for acute respiratory failure.
                Random assignment to receive either 0.43 IU (approximately 0.14 mg) recombinant growth hormone/kg body weight/day (treated group), or saline (nontreated group) for 12 days.
                Nutritional support was guided by indirect calorimetry. Cumulative nitrogen balance was positive throughout the study period in the treated group 17.3 (44.9 +/- 17.3[SEM] g/12 days) vs. the nontreated group (-65.8 +/- 11.8 g/12 days) (p<.0001). Despite similar initial plasma concentrations, recombinant growth hormone supplementation resulted in marked increases in growth hormone, insulin like growth factor-1, and insulin concentrations (p<.05, .02, and .0001, respectively, vs. nontreated group). Body impedance determined net fat-free mass increased in the treated group (0.8 +/- 0.6 kg) vs. the nontreated group (-1.1 +/- O.5 kg) (p<.03). Initial peripheral muscle function, assessed by computer-controlled electrical stimulation of the adductor pollicis, was similarly lower in treated and nontreated groups than sex and age-matched normal controls, and decreased further during the study period. Arterial blood gases, cumulative total mechanical ventilation time, and number of hrs/day of mechanical ventilation during weaning were similar in both patient groups. Only three of the ten patients in each group were weaned from mechanical ventilation by day 12.
                Daily administration of recombinant growth hormone in mechanically ventilated patients with acute respiratory failure promotes a marked nitrogen retention. However, this reaction is accompanied neither by an improvement in muscle strength nor by a shorter duration of ventilatory supports. The effect of growth hormone (GH) treatment on exercise tolerance in children with cystic fibrosis was investigated.
                10 prepubertal children (mean +/- SD; age: 12.1 +/- 1.7 yr; height: 137.4 +/- 9.2 cm; body mass: 27.8 +/- 4.2 kg; forced expiratory volume in 1 s (FEV1): 68 +/- 22% predicted) were randomly assigned to either control period (CON, standard therapy) or recombinant human growth hormone (GH) period (additional GH treatment, 0.11-0.14 IU.kg-1, daily, s.c.) for the first 6 months, and then assigned to the other period for the next 6 months. At study entry and after each period, anthropometric data, pulmonary function, and exercise capacity (peak exercise capacity, .VO(2peak), and isokinetic muscle strength) were measured.
                Changes in height (+4.3 +/- 1.0 cm), total body mass (+2.2 +/- 0.8 kg), and lean body mass (LBM, +2.9 +/- 0.7 kg) were significantly higher (P < 0.01) after GH treatment compared with CON. Pulmonary function did not significantly change in either of the periods. In contrast to CON, GH treatment improved absolute .VO(2peak) (+19%, P < 0.01), peak ventilation (+14%, P < 0.01), and peak oxygen pulse (+18%, P < 0.01). Analysis of variance revealed that most of the changes (71%) in .VO(2peak) could be explained by those in LBM and FEV1 (P = 0.001).
                GH treatment clearly improved exercise tolerance, presumably resulting from the combined effects of GH on the muscular, cardiovascular, and pulmonary capacity.
Recombinant growth hormone therapy is effective in improving the intermediate outcomes in height, weight and lean tissue mass when compared with no treatment. One measure of pulmonary function test showed moderate improvement. No significant changes in quality of life, clinical status or side-effects were observed in this review. Long-term, well-designed randomised controlled trials of recombinant growth hormone therapy in patients with cystic fibrosis are required prior to evaluation of human growth hormone treatment for routine use in patients.