Focal brain atrophy in gastric bypass patients with cognitive complaints.

Recently, we have identified a series of patients presenting with cognitive complaints after gastric bypass, without any identifiable etiology. We aimed to determine if focal brain atrophy could account for the complaints. A retrospective case series was performed to identify patients with cognitive complaints following gastric bypass who had a volumetric MRI. Voxel-based morphometry was used to assess patterns of grey matter loss in all 10 patients identified, compared to 10 age and gender-matched controls. All patients had undergone Roux-en-Y gastric bypass surgery at a median age of 54 (range: 46-64). Cognitive complaints developed at a median age of 57 (52-69). Formal neuropsychometric testing revealed only minor deficits. No nutritional abnormalities were identified. Voxel-based morphometry demonstrated focal thalamic atrophy in the gastric bypass patients when compared to controls. Patients with cognitive complaints after gastric bypass surgery may have focal thalamic brain atrophy that could result in cognitive impairment.