Background: Although most bariatric surgery patients undergo a preoperative psychological evaluation, the potential effect of psychiatric disorders on weight loss is not well understood. We sought to document the relationship of preoperative psychiatric disorders to the 6-month outcomes after gastric bypass.
Methods: The Structured Clinical Interview for the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV) was used to assess current and lifetime Axis I clinical disorders, as well as Axis II personality disorders, before surgery. We used linear regression models to examine the relationship of psychiatric disorders to postoperative weight-related outcomes.
Results: The sample (n = 207) was 83.1% female and 92.7% white. The preoperative body mass index (BMI) was 51.4 +/- 9.6 kg/m(2) and age was 45.8 +/- 9.5 years. After adjusting for the initial BMI, gender, race, and age, a lifetime Axis I disorder was associated with a smaller decrease in BMI (t = -3.7, df = 205, P <.001) at 6 months after surgery. The results of separate models for each class of disorder indicated that lifetime mood disorder was associated with a smaller decrease in BMI (t = -3.7, df = 205, P <.001), as was lifetime anxiety disorder (t = -2.6, df = 205, P = 0.009), but substance and eating disorders were not. In this sample, current Axis I clinical disorders and Axis II personality disorders were unrelated to outcomes at 6 months. Similar overall results were found when the percentage of weight loss and excess weight loss were predicted.
Conclusion: The results of our study have shown that patients who have ever had an Axis I clinical disorder, especially mood or anxiety, exhibit poorer weight outcomes 6 months after gastric bypass than those who have never had an Axis I disorder. Additional research with larger samples is needed to replicate these findings and examine more fully the effect of current clinical disorders and personality disorders on weight loss. Nevertheless, our results suggest that patients with current or past disorders might benefit from close monitoring or psychosocial intervention to improve their short-term outcomes. However, a greater duration of follow-up is needed to identify predictors of longer-term weight control.