Neurologic Manifestations of Vitamin B Deficiency after Bariatric Surgery

INTRODUCTION: The aim of this study was to assess the incidence, clinical presentation, and outcomes of neurologic disorders secondary to vitamin B deficiencies following bariatric surgery.

METHODS: Patients at a single academic institution who underwent bariatric surgery and developed neurologic complications secondary to low levels of vitamins B1, B2, B6, and B12 between the years 2004 and 2015 were studied.

RESULTS: In total, 47 (0.7%) bariatric surgical patients (Roux-en-Y gastric bypass n = 36, sleeve gastrectomy n = 9, and duodenal switch n = 2) developed neurologic manifestations secondary to vitamin B deficiencies. Eleven (23%) patients developed postoperative anatomical complications contributed to poor oral intake. Median duration to onset of neurologic manifestation following surgery was 12 months (IQR, 5-32). Vitamin deficiencies reported in the cohort included B1 (n = 30), B2 (n = 1), B6 (n = 12), and B12 (n = 12) deficiency. The most common manifestations were paresthesia (n = 31), muscle weakness (n = 15), abnormal gait (n = 11), and polyneuropathy (n = 7). Four patients were diagnosed with Wernicke-Korsakoff syndrome (WKS) which was developed after gastric bypass (n = 3) and sleeve gastrectomy (n = 1). Seven patients required readmission for management of severe vitamin B deficiencies. Overall, resolution of neurologic symptoms with nutritional interventions and pharmacotherapy was noted in 40 patients (85%). The WKS was not reversible, and all four patients had residual mild ataxia and nystagmus at the last follow-up time.

CONCLUSIONS: Nutritional neurologic disorders secondary to vitamin B deficiency are relatively uncommon after bariatric surgery. While neurologic disorders are reversible in most patients (85%) with vitamin replacements, persistent residual neurologic symptoms are common in patients with WKS.