SOURCE: Zoppini G, et al. Prevalence of cardiovascular autonomic neuropathy in a cohort of patients with newly diagnosed type 2 diabetes: The Verona Newly Diagnosed Type 2 Diabetes Study (VNDS). Diabetes Care 2015;38:1487-1493.
The most common neuropathy seen in type 2 diabetes (T2DM) is symmetrical distal neuropathy, which usually affects both lower extremities. T2DM is also characterized by a variety of autonomic neuropathies that have the potential to impact adrenergic, cholinergic, and dopaminergic pathways.
Cardiovascular autonomic neuropathy (CAN) may include neuropathy to the heart and vasculature. Sympathetic overactivity in CAN has been associated with arrhythmias and sudden cardiac death. Confirmation of CAN requires somewhat sophisticated tests, and there has been some inconsistency of diagnostic criteria, both of which have likely contributed to a low level of awareness of CAN and its consequences. The Verona Newly Diagnosed T2DM Study (n = 813) included a large subgroup of subjects who agreed to undergo cardiac autonomic testing (n = 557).
Depending on the strictness of testing criteria, the prevalence of CAN was at least 1.8% at baseline (strict criteria), but as high as 15.3% when less strict criteria were utilized.
Clinicians typically have thought of neuropathic changes in T2DM as a reflection of long-term disease. This study is the largest population study of newly diagnosed persons with T2DM that studied CAN at baseline. These results suggest that CAN may occur quite early. Whether treatment of diabetes might alter the course of CAN remains unknown.