Increased basal cortisol levels have been found in bulimia nervosa. After stress, increased cortisol levels have been associated with increased food intake in healthy women. Therefore, we assessed cortisol, hunger, and desire to binge eat after a cold pressor test (CPT) among women with binge eating disorder (BED).
Twenty-two obese (body mass index [BMI] = 36.7 ± 6.5 SD) females (11 non-BED, 11 BED) completed the Zung depression scale and underwent the CPT, hand submerged in ice water for 2 minutes. Over 60 minutes, periodic ratings of hunger and desire to binge eat were obtained, just before blood draws for cortisol, as well as insulin. On a separate day, participants had a 1-mg oral dexamethasone suppression test (DST).
The BED group had higher depression scores than the non-BED (p = .04), but depression was not a significant covariate for the cortisol response or to DST. After controlling for contraceptive use (n = 3), the BED group had higher basal cortisol than the non-BED group (p = .03), but cortisol did not differ after DST (p = .40). The BED group had nearly significant greater cortisol AUC after the CPT (p = .057) after controlling for insulin AUC and contraceptive use (p = .057). The BED group also had greater AUC for hunger (p = .03) and desire to binge eat (p = .02) after the CPT.
These findings support our hypothesis of a hyperactive HPA-axis in BED, which may contribute to greater hunger and binge eating.
AN = anorexia nervosa;
AUC = area under the curve;
BED = binge eating disorder;
BMI = body mass index;
BN = bulimia nervosa;
CPT = cold pressor test;
DST = dexamethasone suppression test;
HPA = hypothalamic pituitary adrenal;
VAS = visual analogue scale;
WHR = waist-hip ratio.