Are the Results of a Combined Behavioural and Surgical Treatment of Morbid Obesity Satisfactory and Predictable?

Treatment of subjects with morbid obesity (Body Mass Index (BMI) > 40 kg/m(2) or > 35 kg/m(2) with obesity-related complications) often fails. This study explored the biopsychosocial predictors of dropout and weight loss during a combined behavioural and surgical weight-reduction program. Behavioural treatment for six months was followed by bariatric surgery and a visit six months after surgery. The success criterion was the loss of ≥50% of excess BMI above 25 kg/m(2) (%EBMIL). Thirty-one men and 113 women with BMI 43.5 kg/m(2) (SD 4.3) and 41.8 kg/m(2) (SD 3.6), respectively, were included; 115 underwent bariatric surgery (Gastric sleeve: 23; Roux-en-Y gastric bypass: 92), and 98 had a follow-up visit six months after surgery. The mean %EBMIL at follow-up was 71.2% (SD 18.5). Treatment success was achieved in 86 subjects. Assuming success in 17 subjects who did not attend the follow-up visit (best possible outcome), 103 out of 144 subjects (72%) achieved successful weight reduction. Cohabitation was the only predictor of accomplishing surgery. Neither weight loss during behavioural therapy nor biopsychosocial factors were found to be clinically significant predictors of weight loss after surgery. The success rate of less than three in four subjects was unsatisfactory. There is a need to improve the regimen and to determine effective alternative interventions.