Diabetic neuropathy: prevalence, concordance between clinical and electrophysiological testing and impact of risk...

The aim of this study was to assess the prevalence of various forms of diabetic neuropathy (DN), by clinical and electrophysiological tests, on 374 diabetic patients (66 with type 1 and 308 with type 2 diabetes mellitus) and the concordance between clinical and electroneurological alterations and relative risk factors impact. The overall prevalence of DN, according to the Saint Antonio Conference criteria, was 44.9% (28.88% somatic, 14.44% mixed and 1.60% autonomic) without statistical difference between type 2 and type 1 diabetes (46.43% and 37.88% respectively). In 32.24% of patients nerve conduction velocity (NCV) abnormalities were present together with clinical signs or symptoms of neuropathy, while 12.68% presented only signs and/or symptoms. In addition 9.36% of patients showed alterations of NCV in the absence of clinical signs or symptoms of neuropathy. The most frequent form was asymptomatic (30.21%), followed by symptomatic neuropathy (12.83%); rare was the severe neuropathy. Relative risk increased for diabetes duration > 20 years (p < 0.0001).

1) the Saint Antonio Consensus Conference criteria can be considered the most complete test for neuropathy diagnosis; 2) NCV alterations may not be concordant with signs-symptoms of neuropathy; 3) the duration of diabetes seems to be the most important risk factor.