Bright light therapy decreases winter binge frequency in women with bulimia nervosa: A double-blind, placebo-controlled study

The study objective was to determine the effect of winter bright light ther apy on binge and purge frequencies and depressive symptoms in subjects with bulimia nervosa. Thirty-four female bulimic outpatients were treated with either 10,000 lux bright white light or 50 lux dim red light (placebo contr ol) during the winter months. In this double-blind study, the placebo group (n = 18) and the bright light group (n = 16) were matched for age, degree of seasonality (measured by the Seasonal Patterns Assessment Questionnaire [SPAQ]), and concurrent depression (measured by Structured Clinical Intervi ew for DSM-IV [SCID]), Three weeks of baseline data collection were followe d by 3 weeks of half-hour daily morning light treatment and 2 weeks of foll ow-up evaluation. There was a significant light-treatment by time interacti on (Wilks' lambda = .81, F(2,28) = 3,31, P = .05). The mean binge frequency decreased significantly more from baseline to the end of treatment for the bright light group (F(1,29) = 6.41, P = .017) than for the placebo group. The level of depression (measured by daily Beck Depression Inventory [BDI] scores) did not significantly differ between the groups during any phase, a nd neither depression nor seasonality affected the response to light treatm ent, In this double-blind study, bulimic women who received 3 weeks of wint er bright light treatment reported a reduced binge frequency between baseli ne and the active treatment period in comparison to subjects receiving dim red light. Copyright (C) 1999 by W.B. Saunders Company.