The burden of neuropathic pain: a systematic review and meta-analysis of health utilities.

Patients with neuropathic pain (NeuP) experience substantially lower health-related quality of life (HRQoL) than the general population. The aim of this systematic review and meta-analysis is to test the hypothesis that NeuP is associated with low levels of health utility. A structured search of electronic databases (MEDLINE, EMBASE, Cochrane Library and CINAHL) was undertaken. Reference lists of retrieved reports were also reviewed. Studies reporting utility single-index measures (preference based) in NeuP were included. Random effects meta-analysis was used to pool EQ-5D index utility estimates across NeuP conditions. The association of utilities and pre-defined factors (NeuP condition, patient age, sex, duration and severity of pain and method of utility scoring) was examined using meta-regression. Twenty-four studies reporting health utility values in patients with NeuP were included in the review. Weighted pooled utility score across the studies varied from a mean of 0.15 for failed back surgery syndrome to 0.61 for post-herpetic neuralgia and diabetic neuropathy. Although there was substantial heterogeneity (P<0.0001) across studies, we found little variation in utility as a function of patient and study characteristics. The single exception was a significant relationship (P<0.0001) between increasing neuropathic pain severity and a reduction in utility. This study confirms the hypothesis that patients with NeuP experience low utilities and therefore low HRQoL. However, the contribution of non-NeuP co-morbidity remains unclear. Neuropathic pain severity emerged as a primary predictor of the negative health impact of NeuP.