Prevalence and impact on quality of life of peripheral neuropathy with or without neuropathic pain in type 1 and type 2 diabetic patients attending hospital outpatients clinics

Abstract

Diabetic polyneuropathy (DPN) without or with neuropathic pain (DPN-P) is one of the most frequent complications of diabetes. To better delineate their respective prevalences, we conducted a cross-sectional study that included 1111 patients (767 type 2 and 344 type 1 diabetic patients) followed up in diabetic outpatients clinics. The association of DPN and DPN-P with other diabetic complications, the impact on quality of life (QoL) and pain management were also investigated. Two validated tools (Neuropen) and the DN4 questionnaire) were used to diagnose the two conditions. Pain intensity was measured using a visual analogue scale, and participants completed the 12-item Short-Form Health Survey to evaluate the physical and mental components of QoL. Univariate and multivariate models were used for the statistical analyses. The prevalence of DPN was 43% (95% CI 40.1-45.9), and was higher in type 2 (50.8%) than in type 1 (25.6%) diabetic patients. The prevalence of DPN-P was 14% (95% CI 12.1-16.2) which, again, was higher in type 2 (17.9%) than in type 1 (5.8%) patients. These prevalences both increased with age and diabetes duration. Nephropathy, obesity, low HDL cholesterol and high triglyceride levels were independently associated with DPN and/or DPN-P. Physical and mental components of QoL were significantly altered by DPN-P, but not DPN. Only half of the DPN-P patients were using analgesic treatment, while 28% were using anticonvulsants or antidepressants. DPN and DPN-P are frequent complications of diabetes, especially in type 2, and can be identified with inexpensive and easy-to-use screening tools. Despite its profound impact on QoL, DPN-P remains undertreated.