Homocysteine and Cognition in Bariatric Surgery

Abstract

Purpose: The aim of this study was to investigate the effects of bariatric surgery on homocysteine serum levels with respect to cognitive functioning and level of depression. Materials and Methods: Fasting homocysteine, vitamin B12, and folate levels were measured in 99 patients; 48 bariatric surgery candidates and 51 postbariatric patients with a mean excess weight loss of at least 40%. Cognitive performance in all subjects was evaluated by a computerized test battery. Depression was assessed using the depression module of the Patient Health Questionnaire. Results: We found a significant relationship between gender, folate, and affiliation and the pre/postgroup and homocysteine levels. Postoperative patients' homocysteine levels were significantly higher compared with preoperative levels. Regarding cognitive functioning, bivariate correlations suggested a link between homocysteine and verbal learning/short-term memory, measured with the Auditory Verbal Learning Test as a trend, not reaching significance. Multivariate analysis showed that it was not homocysteine but affiliation to the pre- or postoperative group that was significantly associated with the level of depression. Applying the Auditory Verbal Learning Test as a dependent variable, male gender and younger age were associated with better task performance, but homocysteine was not. Conclusions: Our results do not support a relevant pathophysiological role of homocysteine levels in cognitive performance early after bariatric surgery.