Pre-operative history of depression and cognitive changes in bariatric surgery patients.

Obesity-associated cognitive impairments may be partially reversible through bariatric surgery. Depression, a prevalent comorbidity in bariatric surgery candidates, is linked with cognitive impairment and poorer surgical outcomes in other populations. No study has examined the effects of pre-operative depression on cognitive changes in bariatric surgery patients. Sixty-seven bariatric surgery patients completed a computerized cognitive test battery prior to surgery and 12 months post-operatively. The structured clinical interview for the DSM-IV Axis I disorders assessed major depressive disorder (MDD). Pre-surgery history of MDD was found in 47.8% of patients, but was not associated with greater baseline cognitive impairments. Repeated measures revealed improved cognitive abilities 12 months after surgery. Pre-surgery history of MDD did not influence post-operative cognitive function. Pre-operative history of MDD did not limit post-operative cognitive improvements. Larger studies with extended follow-ups are needed to clarify our findings and identify factors (e.g. older age) that may modify cognitive changes following surgery.