Hsieh LC, et al. Effect of beta-hydroxy-beta-methylbutyrate on protein metabolism in bed-ridden elderly receiving tube feeding. Asia Pac J Clin Nutr. 2010;19(2):200-8.
This randomized, controlled trial investigated the effect of HMB on body composition and protein metabolism in bed-ridden elderly patients fed by nasogastric tube. The subjects were randomized to either the HMB (n=39) or control group (n=40). Anthropometry measurements, blood sampling, and 24 hour urine samples were collected at baseline and 14 days after study initiation. A subset of patients (HMB, n=19; control, n=20) continued the study until day 28. Changes in body weight and BMI were not significantly different between the control and treatment groups on days 14 or 28. However, blood urea nitrogen significantly decreased in the HMB group (p<0.05), but remained unchanged in the control group after 14 days. Urinary urea nitrogen also significantly decreased in the HMB group (p<0.05), while it showed a trend toward increase in the control group at 14 and 28 days. The investigators concluded that HMB supplementation for 2 to 4 weeks could reduce muscle breakdown in elderly bed-ridden nursing home patients receiving tube feeding.
Berk L, et al. A randomized, double-blind, placebo-controlled trial of a beta-hydroxyl beta-methyl butyrate, glutamine, and arginine mixture for the treatment of cancer cachexia. Support Care Cancer. 2008 Oct;16(10):1179-88.
This randomized, double-blind trial enrolled 472 advanced cancer patients who had between 2% and 10% weight loss. Patients were randomized to receive either an isonitrogenous, isocaloric control mixture (n=237) or, Juven® (n=235), a commercially available formula containing HMB, glutamine, and arginine. Patients received an 8-week supply of Juven or the control at the initial visit and were evaluated at 4- and 8-week follow-up. The primary endpoint was the percentage increase in lean body mass at 8 weeks as compared to baseline. Secondary endpoints were change in fatigue, quality of life, percent change in weight, and percent change in lean body mass. Based on an intent-to-treat analysis, there was no statistically significant difference in lean body mass between the control and treatment groups at 8 weeks. There were also no statistically significant differences in secondary endpoints between the two groups. However, patients on Juven showed a strongly higher trend throughout the study in a secondary lean body mass endpoint (measured using area under the curve [AUC]) evaluated by bioimpedance (p=0.08) and skin fold measurements (p=0.08). The investigators concluded that Juven failed to prevent lean body mass loss among cancer cachexia patients. However, the improving trend in lean body mass when measured using AUC suggests that further study is warranted.