Managing Risk of Non-Communicable Diseases in Women with Bulimia Nervosa or Binge Eating Disorders: A Randomized Trial with 12 Months Follow-Up

Abstract

Persons with bulimia nervosa (BN) or binge eating disorder (BED) have an elevated risk of non-communicable diseases (NCDs). However, lowering this risk is rarely addressed in standard cognitive-behavioral treatment (CBT). We aimed to compare CBT with an intervention combining physical exercise and dietary therapy (PED-t), and hypothesized that the PED-t would do better than CBT in lowering the risk of NCD both initially and longitudinally. In this study, 164 women with bulimia nervosa or binge eating disorder were randomly assigned to 16-weeks of outpatient group therapy with either PED-t or CBT. Body composition (BC) was measured by dual-energy X-ray absorptiometry. Measures of physical fitness (VO₂peak and one repetition maximum (1RM) in squats, bench press, and seated row) were also recorded. All measurements were completed baseline, post-treatment, and at 6- and 12-month follow-ups, respectively. Our results showed that PED-t improved more than CBT on mean (99% CI) absolute Vo2peak; 57,2 (84.4, 198.8) mL (g = 0.22, p < 0.001) post-treatment. There were small to medium long-term differences in 1RM after PED-t compared to CBT. BC deteriorated in both groups during follow-up. Neither the PED-t nor the CBT lowered the risk for NCDs. Clearly, other approaches need to be considered to promote physical fitness and lower the risk of NCDs among individuals with BN and BED.

Keywords: binge eating disorder; bulimia; eating disorders; exercise; nutrition; obesity; physical activity; physical fitness; visceral adipose tissue.

Figure 1

Recruitment, retention, and attrition during test periods. Overview of recruitment, screening, randomization, and attendance to the baseline (T1), post-treatment (T2), and follow-up measures (T3–T4). PED-t: physical exercise and dietary therapy; CBT: cognitive behavior therapy; BN: bulimia nervosa; BED: binge-eating disorder; EDE-q: eating disorder examination questionnaire; LFU: lost to follow up; ¹ Fairburn and Beglin, 2008 [29]; ² Sheehan, Lecrubier, Sheehan, et al., 1998 [30].

Figure 2

Changes in soft tissue body composition after PED-t or CBT. Results are estimated means (99% CI). (a) Changes in total body fat (kg); (b) changes in lean body mass (kg); (c) changes in visceral adipose tissue (gram). PED-t: Physical Exercise and Dietary therapy; CBT: Cognitive Behavior Therapy; 99% CI: 99% confidence interval; T1: baseline; T2: post-treatment; T3: 6 months post-treatment; T4: 12 months post-treatment; α: significant within-group change from T1 in PED-t (p < 0.01); β: significant within-group change from T1 in CBT (p < 0.01).

Figure 3

Changes in proximal femur bone mineral density (BMD), proximal femur BMD Z-score, and spine BMD after PED-t or CBT. Results are estimated means (99% CI). (a) Changes in proximal femur BMD (gram/cm²); (b) changes in proximal femur BMD Z-score; (c) changes in spine BMD (gram/cm²). PED-t: Physical Exercise and Dietary therapy; CBT: Cognitive Behavior Therapy; 99% CI: 99% confidence interval; BMD: bone mineral density; T1: baseline; T2: post-treatment; T3: 6 months post-treatment; T4: 12 months post-treatment; α: significant within-group change from T1 in PED-t (p < 0.01); ε: significant between-group difference (p < 0.01).