On Bariatric Pre-Surgery Evaluation

By Ofer Zur, Ph.D.

Obesity has become the problem about which it’s okay to laugh, sneer, psychoanalyze or moralize. Unlike most other serious medical problems for which surgery is required, the surgical treatment of morbid obesity requires a pre-surgical psychological evaluation. For these reasons it behooves the practitioner to be aware of the evidence-based data about the problem of obesity and its psychological correlates in order to design evaluations which are helpful to the patient and do not further compromise his or her self-esteem.


A quick critical look at facts & fictions about bariatric surgery and pre-surgical evaluation:

  • Bariatric EvaluationPersonality traits have no predictive value for the postoperative course of weight or mental state, according to controlled and uncontrolled trials of the last two decades.
  • Most studies comparing obese and non-obese groups have found no consistent differences in mental health, leading many researchers to conclude that obesity is not associated with general psychological problems.
  • There is a lack of compelling statistical evidence to support that pre-bariatric psychological assessments are accomplishing their intended goals. Across at least five reviews of the pre-bariatric psychological assessment literature published in the past decade, none suggest that psychosocial factors consistently predict weight-related surgery outcomes.
  • The most common items endorsed by practitioners as contraindications for surgery approval were current illicit drug abuse; active, uncontrolled symptoms of schizophrenia; severe intellectual disability (I.Q. <50); heavy drinking and lack of knowledge about the surgery.
  • The association with presence or absence of a pre-surgical psychiatric diagnosis with eventual weight loss is questionable.
  • Many pre-surgical psychological difficulties normalize following surgery, suggesting any psychological disturbances are the consequences, not the causes of morbid obesity.
  • A manifestation of prejudice is that, despite the widely discredited assumption that obese people are of necessity, psychologically disturbed, many professions continue to espouse it.
  • There is no empirical basis for the widely accepted contraindications to bariatric surgery.
  • In a two-year follow-up in the Swedish Obese Subjects study, declining levels of psychological distress were found with increased weight loss.
  • An absence of psychiatric problems and personality disorders has been associated with greater weight loss and positive postoperative psychosocial outcome.
  • In a study of those with a pre-surgical diagnosis of Binge-eating disorder (BED), the subjects had a higher frequency of manageable post-surgical complications and underwent more band adjustments than their non eating-disordered counterparts.
  • Most predictions made from single variables were not significant, even with a relatively large sample size…successful sustained weight loss is related to small contributions from a number of variables.



In summary, the pre-surgical evaluation may be unnecessary and its implementation and acceptance a product of the stigmatization around obesity. As many of you know, transsexuals must also undergo pre-surgical evaluation and obtain a disorder diagnosis before a physician will perform the surgery. Clearly, cultural values influence the placement of red tape.

Sign up for topical updates and invitations to participate with Dr. Zur