Effects of an oral ghrelin mimetic on body composition and clinical outcomes in healthy older adults: a randomized trial.

BACKGROUND: Growth hormone secretion and muscle mass decline from midpuberty throughout life, culminating in sarcopenia, frailty, decreased function, and loss of independence. The decline of growth hormone in the development of sarcopenia is one of many factors, and its etiologic role needs to be demonstrated. OBJECTIVE: To determine whether MK-677, an oral ghrelin mimetic, increases growth hormone secretion into the young-adult range without serious adverse effects, prevents the decline of fat-free mass, and decreases abdominal visceral fat in healthy older adults. DESIGN: 2-year, double-blind, randomized, placebo-controlled, modified-crossover clinical trial. SETTING: General clinical research center study performed at a university hospital. PARTICIPANTS: 65 healthy adults (men, women receiving hormone replacement therapy, and women not receiving hormone replacement therapy) ranging from 60 to 81 years of age. INTERVENTION: Oral administration of MK-677, 25 mg, or placebo once daily. MEASUREMENTS: Growth hormone and insulin-like growth factor I levels. Fat-free mass and abdominal visceral fat were the primary end points after 1 year of treatment. Other end points were body weight, fat mass, insulin sensitivity, lipid and cortisol levels, bone mineral density, limb lean and fat mass, isokinetic strength, function, and quality of life. All end points were assessed at baseline and every 6 months. RESULTS: Daily administration of MK-677 significantly increased growth hormone and insulin-like growth factor I levels to those of healthy young adults without serious adverse effects. Mean fat-free mass decreased in the placebo group but increased in the MK-677 group (change, -0.5 kg [95% CI, -1.1 to 0.2 kg] vs. 1.1 kg [CI, 0.7 to 1.5 kg], respectively; P < 0.001), as did body cell mass, as reflected by intracellular water (change, -1.0 kg [CI, -2.1 to 0.2 kg] vs. 0.8 kg [CI, -0.1 to 1.6 kg], respectively; P = 0.021). No significant differences were observed in abdominal visceral fat or total fat mass; however, the average increase in limb fat was greater in the MK-677 group than the placebo group (1.1 kg vs. 0.24 kg; P = 0.001). Body weight increased 0.8 kg (CI, -0.3 to 1.8 kg) in the placebo group and 2.7 kg (CI, 2.0 to 3.5 kg) in the MK-677 group (P = 0.003). Fasting blood glucose level increased an average of 0.3 mmol/L (5 mg/dL) in the MK-677 group (P = 0.015), and insulin sensitivity decreased. The most frequent side effects were an increase in appetite that subsided in a few months and transient, mild lower-extremity edema and muscle pain. Low-density lipoprotein cholesterol levels decreased in the MK-677 group relative to baseline values (change, -0.14 mmol/L [CI, -0.27 to -0.01 mmol/L]; -5.4 mg/dL [CI, -10.4 to -0.4 mg/dL]; P = 0.026); no differences between groups were observed in total or high-density lipoprotein cholesterol levels. Cortisol levels increased 47 nmol/L (CI, 28 to 71 nmol/L (1.7 microg/dL [CI, 1.0 to 2.6 microg/dL]) in MK-677 recipients (P = 0.020). Changes in bone mineral density consistent with increased bone remodeling occurred in MK-677 recipients. Increased fat-free mass did not result in changes in strength or function. Two-year exploratory analyses confirmed the 1-year results. LIMITATION: Study power (duration and participant number) was insufficient to evaluate functional end points in healthy elderly persons. CONCLUSION: Over 12 months, the ghrelin mimetic MK-677 enhanced pulsatile growth hormone secretion, significantly increased fat-free mass, and was generally well tolerated. Long-term functional and, ultimately, pharmacoeconomic, studies in elderly persons are indicated.

The effects of MK-0677, an oral growth hormone secretagogue, in patients with hip fracture.

OBJECTIVES: To evaluate the effects of MK-0677, an orally active growth hormone (GH) secretagogue, on functional recovery from hip fracture in previously mobile older individuals. DESIGN: Placebo-controlled, randomized, double-blind trial. SETTING: Thirteen medical centers in England, Sweden, Denmark, Belgium, Switzerland, Canada, and the United States. Patients were recruited between 3 and 14 days postoperatively, or no more than 18 days postfracture, at acute care hospitals and rehabilitation centers. PARTICIPANTS: One hundred sixty-one hip-fracture patients were enrolled. Entry criteria included consenting hip-fracture patients who were aged 65 and older and who were ambulatory before their fracture, medically stable postoperatively, and mentally competent. Patients were excluded if they had multiple fractures or severe trauma, diabetes mellitus, cancer, uncontrolled hypertension, congestive heart failure, or total hip replacement in the involved extremity. INTERVENTION: Random assignment to 6 months of daily treatment with MK-0677 or placebo. Patients were followed for an additional 6 months after completion of therapy. MEASUREMENTS: Change from Week 6 to Week 26 in a panel of functional performance measures. Additional outcome measures included change in the Sickness Impact Profile for Nursing Homes (SIP-NH), the ability to live independently, and insulin-like growth factor I (IGF-I) levels. RESULTS: MK-0677 treatment increased serum IGF-I levels by 84% (95% confidence interval (CI)=63-107), compared with an increase of 17% (95% CI=8-28) on placebo. There were no significant differences between MK-0677 and placebo in improvement in functional performance measures or in the overall SIP-NH score. Although MK-0677 patients showed greater improvement relative to placebo in three of four lower extremity functional performance measures, in the physical domain of the SIP, and in the ability to live independently, these differences were not statistically significant. CONCLUSION: Although MK-0677 treatment increased serum IGF-I, it is uncertain whether clinically significant effects on physical function were achieved. Measuring function in clinical trials in hip-fracture patients is difficult because of the lack of validated outcome measures, high variability, and the lack of a baseline assessment. Present functional performance measures may not be sufficiently responsive for use as the primary endpoint of small intervention studies; alternatively, stimulation of GH may not result in significant functional improvement.

Dissecting the workforce and workplace for clinical endocrinology, and the work of endocrinologists early in their careers.

CONTEXT: The United States lacks timely reliable mechanisms for assessing the professional work of subspecialty physicians. OBJECTIVE: The aim was to use early-career members of The Endocrine Society as a model to estimate subspecialty physician involvement in patient care, teaching, research, and administration among clinical, academic, federal, and pharmaceutical/biotech workplaces and to assess the workforce for research within individual workplaces. METHODS: Physicians joining The Endocrine Society from 1991-2005 and residing in North America were invited to complete a Web-based survey. This report relies on 817 early-career endocrinologists or 29.6% of eligible respondents. RESULTS: Respondents from all types of workplaces engaged in patient care, teaching, research, and administration. The time committed to the four tasks, however, differed significantly among workplaces. Research (basic, translational, disease, patient, population, and prevention) was accomplished within all workplaces, but the scope and scale of investigative work was employer dependent. Recipients of National Institutes of Health K08/23 awards succeeded in receiving federal research project grants (P < 0.001). Respondents associated research with lowered incomes, a perception validated by an estimated drop in annual earnings of 2.8% per half-day spent on research (P < 0.001). Women in academic settings earned less than men (P < 0.01) and were less likely to occupy tenure-eligible positions (P < 0.01). CONCLUSIONS: Web-based surveys offer a simple tool for estimating the work of subspecialty physicians and provide a framework for improving biomedical investigation. Several interventions should be considered for endocrinology: recruit physicians from underrepresented demographic groups, increase K08/23 awards, incentivize investigative careers, and improve the national infrastructure for biomedical research.

Incidence and severity of sexual adverse experiences in finasteride and placebo-treated men with benign prostatic hyperplasia.

OBJECTIVES: To evaluate the incidence and resolution of sexual adverse experiences (AEs) in men with benign prostatic hyperplasia treated with finasteride 5 mg compared with placebo. METHODS: The Proscar Long-term Efficacy and Safety Study (PLESS) was a 4-year, randomized, double-blind, placebo-controlled trial assessing the efficacy and safety of finasteride 5 mg in 3040 men, aged 45 to 78 years, with symptomatic benign prostatic hyperplasia, enlarged prostates, and no evidence of prostate cancer. Patients completed a questionnaire at screening regarding their history of sexual dysfunction. During treatment, spontaneously self-reported sexual AEs were recorded. RESULTS: At screening, 46% of patients in each treatment group reported some history of sexual dysfunction. During year 1 of the study, 15% of finasteride-treated patients and 7% of placebo-treated patients had sexual AEs that were considered drug related by the investigator (P <0.001). During years 2 to 4, no between-group difference was noted in the incidence of new sexual AEs (7% in each group). The drug-related sexual AE profile for finasteride was similar for men with or without a history of sexual dysfunction. Sexual AEs resolved while continuing therapy in 12% of finasteride patients and 19% of placebo patients. Only 4% of finasteride and 2% of placebo patients discontinued the study because of sexual AEs. In men who discontinued with a sexual AE, 50% and 41% experienced resolution of their sexual AE after discontinuing finasteride or placebo therapy, respectively. CONCLUSIONS: Compared with placebo, men treated with finasteride experienced new drug-related sexual AEs with an increased incidence only during the first year of therapy.