QUESTIONS AND ANSWERS

Are Chromium Supplements Useful for Patients with Binge Eating Disorder?

Q. I recently heard a colleague talking about chromium supplements for patients with binge eating disorder (BED). Is there any validity to this approach? (GS, Melbourne, Australia)

A. Chromium was discovered in France in the late 1790s, but it was the 1960s before it was recognized as being an important trace element. Chromium is an essential element that affects insulin sensitivity and serotonin function. Chromium supplementation has been widely studied for glucose regulation in patients with type-2 diabetes mellitus and related metabolic conditions and for mood regulation in patients with atypical depression.

At the 2015 ICED meeting in Boston, Lauren Breithaupt from George Mason University and colleagues at the University of North Carolina, Chapel Hill, reported the results of the first pilot study of chromium supplementation for patients with BED. Twenty-one (of 24 randomized) overweight adults with BED completed a 6-month placebo-controlled study of chromium picolinate (CrPic). At a 3-month follow-up visit, all the subjects completed feasibility and acceptability questionnaires. According to the authors, the study results were overwhelmingly positive. Participants felt the study was helpful in terms of symptom improvement and reported no barriers to treatment. No study participants dropped out due to negative side effects. Little is known about the true effectiveness of supplements for eating disorder treatment. These results should encourage further work in the area.

— SC

Can Leptin Levels Be Used to Predict Outcome in Anorexia Nervosa?

Q. I’ve heard that leptin, a hormone produced by fat cells and that can reflect body fat stores, may help predict the outcome of treatment for anorexia nervosa (AN). Can you comment on this? (TJ, Dallas, TX)

A. A recent study at Columbia University and Florida State University evaluated whether leptin levels could predict a positive outcome for women treated for AN. Jonathan Hersch and colleagues reported at the recent International Conference on Eating Disorders in April that his group evaluated a group of 54 women hospitalized for acute treatment of AN. After the women had gained and maintained a body mass index (BMI, kg/m²) of 19.5 for at least 2 weeks, the researchers evaluated their body composition using total body magnetic resonance imaging and fasting leptin levels. The 54 patients were asked to return to the clinic one year later, for a brief clinical assessment and weight evaluation. Their treatment outcome was defined by their BMIs: those who maintained a BMI greater than 18.5 kg/m² were considered successful, while those with BMIs lower than this were deemed treatment failures. The researchers then used independent sample t-tests, demographic data, body composition, and leptin levels to compare the “success” and “failure” groups. Binary logistic regression was also constructed to evaluate the relationship between pre-discharge leptin level and outcome at one year.

Data from 46 participants were available for analysis. Twenty-four of the women met the outcome criteria for success, while 22 were deemed to have treatment failure. There were some differences between the two groups. The “success” group tended to be slightly younger (23+4 years vs 26+6 years; p=0.09) and had a somewhat shorter duration of illness (6+3 years vs 9+8 years; p=0.08). The pre-discharge BMIs were not different between the two groups but percent body fat was higher in the “success” group (27+4%) compared to the “failure” (23+5%) group (p=0.003).

In the “success” group, both leptin (16+18 ng/mL) and leptin normalized for fat mass (0.99+0.97 ng/mL/kg) levels were significantly higher compared to those of the “failure” group (leptin: 6.3+6.4 ng/mL p=0.02, leptin/fat mass: 0.47+0.43 ng/mL/kg, p=0.03). Pre-discharge leptin (p=0.04) and leptin/fat mass (p=0.02) but not BMI (p=0.20) significantly predicted treatment outcome at one year.

This study suggests leptin levels may eventually be a clinically useful predictor of outcome in AN. The study is a good start, but more research is needed to confirm the potential role of leptin as a clinical marker in AN.

— SC