A simplified protocol to screen for distal polyneuropathy in type 2 diabetic patients

To test a simplified protocol to screen type 2 diabetic patients (DM2) for distal polyneuropathy (DPN), 80 outpatients and 45 controls answered a symptom questionnaire, underwent a directed examination (pin-prick, tuning fork, monofilament, ankle jerk, cold spatula and walking on heels), autonomic tests, and an electroneurophysiological study (EMG). Symptoms were also analysed as scores. DPN was diagnosed in the presence of abnormal EMG (or autonomic neuropathy), plus one symptom or one abnormal objective finding. Symptoms were equally frequent in patients (56%) and controls (35%, P=0.20). Objective findings were more frequent in patients (62/80 versus 11/45; P<0.05). The 60 DM2 patients with DPN were older, with longer diabetes duration and more often hypertensive than those without DPN. The 15 patients unable to walk on heels had DPN (sensitivity 20.8%, specificity 100%, positive predictive value 100% and negative predictive value 12.3%). The 12 patients able to walk on heels but with three or more abnormal tests had DPN (sensitivity 21.1%, specificity 100%, positive predictive value 100% and negative predictive value 15.1%). Isolated signs and symptoms do not identify patients with DPN. Patients with higher degrees of impairment can be identified by six simple ambulatory tests, reducing in one-third the need for EMG.