Morbid obesity is a serious public health problem due to its increasing prevalence, increased morbidity and mortality and medical and psychological consequence. Obesity has a multifactorial etiology that includes genetic, environmental, dietary, cultural and psychosocial factors.

The surgical treatment of obesity has been consistently shown to be effective in long-term marked weight loss and in bringing significant improvement to medical comorbidities. Surgery is indicated in patients with BMI greater than 35 kg/m2 with severe obesity-related comorbidity and for those with BMI greater than 40 kg/m2 with or without comorbidity. Surgery candidates should be selected and evaluated in order to achieve optimal outcomes.

Psychological factors are thought to play an important role for maintaining the surgical weight loss. The findings suggest that pre-surgical cognitive function, personality, state of mental health, psychological variables and binge eating may predict post-surgical weight loss to the extent that these factors influence post-operative eating behaviour.

The high prevalence of psychiatric disorders in surgery candidates is gaining more attention than before. Studies show that around 40% of all bariatric surgery patients have at least one psychiatric diagnosis. Depressive, anxiety, and binge eating disorders are the most common diagnoses and should be treated before surgery. The most common psychiatric conditions contraindicated to surgery are active psychosis, current substance abuse, heavy drinking, and multiple suicide attempts or a suicide attempt within the previous year.

We made a review of literature on psychological predictors of surgical weight loss in order to clarify the role of pre-surgical psychiatric evaluation.