Clinical diagnosis of diabetic polyneuropathy with the diabetic neuropathy symptom and diabetic neuropathy examination scores

OBJECTIVE - To evaluate the discriminative power of the Diabetic Neuropathy Symptom (DNS) and Diabetic Neuropathy Examination (DNE) scores for diagnosing diabetic polyneuropathy (PNP), as well as their relation with cardiovascular autonomic function testing (cAFT) and electro-diagnostic studies (EDS). RESEARCH DESIGN AND METHODS - Three groups (matched for age and sex) were selected: 24 diabetic patients with neuropathic foot ulcers (DU), 24 diabetic patients without clinical neuropathy or ulcers (DC), and 21 control subjects without diabetes (C). In all participants, the DNS and DNE scores were assessed and cAFT (heart rate variability [HRV], baroreflex sensitivity [BRS]), and EDS were performed (Nerve Conduction Sum [NCS] score; muscle fiber conduction velocity fastest/slowest ratio [F/S ratio]). RESULTS - Both the DNS and the DNE scores discriminated between the DU and DC groups significantly (P < 0.001). The DNE score even discriminated between DC and C (P < 0.05). Spearman's correlation coefficients between both DNS and DNE scores and cAFT (HRV -0.42 and -0.44; BRS -0.30 and -0.29, respectively) and EDS (NCS 0.51 and 0.62; F/S ratio 0.44 and 0.62, respectively) were high. Odds ratios were calculated for both DNS and DNE score, with cAFT (HRV 4.4 and 5.7; BRS 20.7 and 14.2, respectively) and EDS (NCS 5.6 and 16.8; F/S ratio 7.2 and 18.8, respectively). CONCLUSIONS - The DNS and DNE scores are able to discriminate between patients with and without PNP and are strongly related to cAFT and EDS. This further confirms the strength of the DNS and DNE scores in diagnosing diabetic PNP in daily clinical practice.