Prevalence and characteristics of painful diabetic neuropathy in a large community-based diabetic population in the U.K.

OBJECTIVE - To assess, in the general diabetic population, 1) the prevalence of painful neuropathic symptoms; 2) the relationship between symptoms and clinical severity of neuropathy; and 3) the role of diabetes type, sex, and ethnicity in painful neuropathy. RESEARCH DESIGN AND METHODS - Observational study of a large cohort of diabetic patients receiving community-based health care in northwest England (n = 15,692). Painful diabetic neuropathy (PDN) was assessed using neuropathy symptom score (NSS) and neuropathy disability score (NDS). RESULTS - Prevalence of painful symptoms (NSS ≥5) and PDN (NSS ≥5 and NDS ≥3) was 34 and 21%, respectively. Painful symptoms occurred in 26% of patients without neuropathy (NDS ≤2) and 60% of patients with severe neuropathy (NDS >8). Adjusted risk of painful neuropathic symptoms in type 2 diabetes was double that of type 1 diabetes (odds ratio [OR] = 2.1 [95% CI 1.7-2.4], P <0.001) and not affected by severity of neuropathy, insulin use, foot deformities, smoking, or alcohol. Women had 50% increased adjusted risk of painful symptoms compared with men (OR = 1.5 [1.4-1.6], P <0.0001). Despite less neuropathy in South Asians (14%) than Europeans (22%) and African Caribbeans (21%) (P <0.0001), painful symptoms were greater in South Asians (38 vs. 34 vs. 32%, P <0.0001). South Asians without neuropathy maintained a 50% increased risk of painful neuropathy symptoms compared with other ethnic groups (P <0.0001). CONCLUSIONS - One-third of all community-based diabetic patients have painful neuropathy symptoms, regardless of their neuropathic deficit. PDN was more prevalent in patients with type 2 diabetes, women, and people of South Asian origin. This highlights a significant morbidity due to painful neuropathy and identifies key groups who warrant screening for PDN. © 2011 by the American Diabetes Association.