Painful diabetic polyneuropathy and quality of life in Danish type 2 diabetic patients

Background and aims Painful polyneuropathy (PPN) is a disabling complication of diabetes. This study aims to determine its prevalence and relationship with Quality of Life (QoL) in a nationwide prospective cohort of incident recently diagnosed Danish type 2 diabetic patients. Methods We sent a detailed questionnaire on neuropathy, pain and QoL to 6726 patients prospectively enrolled from general practitioners and hospital specialist outpatient clinics into the Danish Centre for Strategic Research in Type 2 Diabetes (DD2) cohort. Patients who reported pain in both feet and a score ≥3 on the Douleur Neuropathique (DN4) questionnaire were considered to have possible PPN. QoL and pain intensity were measured on a numeric rating scale (NRS, 0–10). The Michigan Neuropathy Screening Instrument (MNSI) was used to assess neuropathy. Results A total of 5371 (79.8%) returned a complete questionnaire. 848 (15.8%) recently diagnosed type 2 diabetic patients reported pain in both feet. Of the 619 patients with pain who completed the DN4 questionnaire, 404 (65.2%) had a DN4 score ≥ 3, corresponding to a prevalence in the total population of possible PPN of 10.3%. Mean pain intensity was 5.2 (SD 2.2) and 89% had a MNSI score ≥ 3. Patients with possible PPN had a substantially lower QoL score than those without PPN (median QoL score 6 versus 8 (p < 0.001)), also when correcting for MNSI score. Conclusions Ten percent of newly diagnosed type 2 diabetic patients in Denmark had possible PPN. Patients with PPN had lower QoL than patients without PPN.