[Psychological factors influencing weight regain after bariatric surgery]

Background Approximately 15 to 40% of bariatric patients regain a significant percentage of their weight lost after surgery. Among psychological variables, control and self-efficacy loci are associated with behaviors related to weight loss. Also, family support can be a risk or protection factor for the maintenance of weight loss. Aim To evaluate the association between psychological variables with weight maintenance or regain after bariatric surgery. Material and Methods We evaluated 97 patients at 4.1 ± 3.4 years after their bariatric surgery. They answered questionnaires about self-efficacy to lose weight, locus of weight control and family functioning style. Regain after surgery was also calculated, through self-report. Results Seventeen percent of patients gained weight. Locus of control (Z = -3.09, p < 0.01), family identity (Z = -3.71, p < 0.01) and self-efficacy (Z = -2.44, p = 0.01), differentiated patients who maintained weight loss from those who re-gained at least 15% of their lost weight. An inverse and significant relationship was observed between the percentage of weight regain and locus of control (r = -0.42, p < 0.01), family identity (r = -0.36, p < 0.01) and self-efficacy (r = -0.34, p <0.01). Conclusions The psychological variables "locus of weight control" and "family identity" are inversely and moderately associated with weight regain in patients subjected to bariatric surgery.