Pathological changes in the vagus nerve in diabetes and chronic alcoholism.

The pathological changes in the vagus nerve removed at necropsy have been studied in patients with chronic alcoholism and diabetes. Morphometric studies on myelinated fibres were performed on the nerve at mid-cervical, lung hilum and diaphragmatic levels. In two insulin-dependent diabetics the density of myelinated fibres was below the lower limit of the control range at all levels. In all the diabetic and chronic alcoholic subjects there was significant reduction in the density of myelinated fibres at the most distal level in the nerve. The degenerative changes in the nerve are consistent with the findings of abnormal vagal function in diabetics and chronic alcoholics.