Clinical and electrophysiological correlations in type 2 diabetes mellitus at diagnosis

The purpose of this study was to evaluate, in newly diagnosed type 2 diabetes mellitus (DM): (1) the prevalence and staging of peripheral neuropathy, as well as its possible relationship with metabolic profile; (2) the clinical value of both the Diabetic Neuropathy Index (DNI) and the Diabetic Neuropathy Score (DNS), and their reciprocal concordance, as a screening method for neuropathy. Thirty-nine newly diagnosed DM subjects underwent: neurological examination, nerve conduction studies (NCS), quantitative sensory system and cardiovascular autonomic function assessments. Peripheral neuropathy was observed in 72% of the subjects (its staging was similar to that of patients with longer disease history), while another 10% of them showed a borderline neuropathy. The Deep Breathing test was abnormal in 28% of the patients; postural hypotension was found in 6%. The same proportion (82%) of subjects who scored positively on the DNI showed altered NCS, while the quantitative sensory system assessments had a low sensitivity in order to detect the neuropathy. No correlation was found between metabolic indexes and DNI/DNS parameters. The high prevalence of peripheral and autonomic function alterations suggests that each newly diagnosed diabetic subject should be screened for neuropathy by the DNI, to reduce the negative prognostic influence of this complication.