Postherpetic neuralgia, diabetic neuropathy, and trigeminal neuralgia - Chronic peripheral neuropathic pain in 58,480 rural Italian primary care patients

Introduction: Chronic peripheral neuropathic pain (CPNP) is a condition due to peripheral nervous system diseases or injury, but its prevalence is unknown in Italian primary care.

Aim: The aim of this study is to assess the prevalence of CPNP in a rural primary care area in Northern Italy.

Materials and methods: A multicenter audit study was carried out in a rural area in Northern Italy with 113 participating general practitioners (GPs) seeing 58,480 patients >18 years during 3 months. Patients who for any reason attended GPs' surgeries and had symptoms suggestive of neuropathic pain (NP) were given the NP diagnostic questionnaire "Douleur Neuropathique en 4 Questions" (DN4) and recorded their pain level on a visual analog scale (VAS).

Results: Chronic NP was established by a DN4 score of ≥4 and a VAS pain score of ≥40 mm for >6 months together with a clinical diagnosis in 448 (254 women and 194 men) out of 58,480 patients giving a prevalence of 0.77%. 179 patients (0.31%) had diabetes neuropathy, 142 (0.24%) had postherpetic pain, 41 (0.07%) had trigeminal neuralgia, 27 (0.05%) had NP postinjury, 27 (0.05%) had NP caused by nerve entrapments, 11 (0.02%) had NP triggered by systemic diseases, and 21 (0.04%) had NP of unknown etiology.

Conclusions: The prevalence of CPNP in this population of primary care attenders in a rural area in Northern Italy was 0.77%. Diabetes neuropathy (0.31%) and postherpetic pain (0.24%) were the two most common subgroups of NP, followed by trigeminal neuralgia (0.07%).