Deterioration of cardiac autonomic function over a period of one year in relation to cardiovascular and somatic neuropathy complications in type 2 diabetes mellitus

Aims: Progression of cardiac autonomic dysfunction (CADF) in relation to severity of diabetic autonomic neuropathy is well documented. But its progression while coexisting with somatic neuropathy (PNP) and cardiovascular disease (CVD) is less described. We monitored CADF over a period of one year in relation to PNP and CVD in patients with type 2 diabetes mellitus. Methods: Cardiac autonomic function was assessed in 104 type 2 diabetics. Based on complications study subjects were divided into four subgroups: Group A (No complications); Group B (with CVD); Group C (with PNP); Group D (with CVD and PNP). The parameters measured were: Expiratory:Inspiratory ratio (E:I ratio) and standard deviation of all the N-N intervals (SDNN). These parameters were measured at the baseline and at follow-up. Data analysis was done by employing suitable statistical tests. Results: In Group B: SDNN declined (p< 0.001); E:I ratio did not change. In Group C: E:I ratio declined (p< 0.01); SDNN did not change. In Group D: SDNN and E:I ratio declined significantly (p< 0.001). Conclusion: CADF coexisting with PNP and CVD deteriorates with time. E:I ratio and SDNN are suitable markers in monitoring CADF coexisting with PNP and CVD respectively in type 2 diabetes mellitus.