Neurological complications of bariatric surgery.

Obesity is reaching pandemic proportions, and the number of bariatric surgeries is increasing. Neurological complications of bariatric procedures are more and more frequently reported and physicians need to recognize and be able to manage them. Neurological complications may result from mechanical or inflammatory mechanisms, but mainly from nutritional deficiencies. Vitamin B12, folate, thiamine, vitamin D, and vitamin E are the most frequent deficiencies. Different patterns of complications can be observed that may differ from time to presentation. At an early stage, immediate peripherical nerve injury, Wernicke's encephalopathy, and polyradiculoneuropathy are the most frequent. Late complications may appear after years and include optic neuropathy, myelopathy, peripherical neuropathy, and myopathy. Bariatric surgery patients should benefit from careful nutritional follow-up with routine monitoring of micronutrients at 6 weeks and 3, 6, and 12 months post-op and then annually after surgery, and multivitamin supplementation for life.