Sensitivity of the DN4 in Screening for Neuropathic Pain Syndromes

Several tools have been developed to screen for neuropathic pain. This study examined the sensitivity of the Douleur Neuropathique en 4 Questions (DN4) in screening for various neuropathic pain syndromes.

This prospective observational study was conducted in 7 Canadian academic pain centers between April 2008 and December 2011. All newly admitted patients (n=2199) were approached and 789 eligible participants form the sample for this analysis. Baseline data included demographics, disability, health-related quality of life, and pain characteristics. Diagnosis of probable or definite neuropathic pain was on the basis of history, neurological examination, and ancillary diagnostic tests.

The mean age of study participants was 53.5 years and 54.7% were female; 83% (n=652/789) screened positive on the DN4 (≥4/10). The sensitivity was highest for central neuropathic pain (92.5%, n=74/80) and generalized polyneuropathies (92.1%, n=139/151), and lowest for trigeminal neuralgia (69.2%, n=36/52). After controlling for confounders, the sensitivity of the DN4 remained significantly higher for individuals with generalized polyneuropathies (odds ratio [OR]=4.35; 95% confidence interval [CI]: 2.15, 8.81), central neuropathic pain (OR=3.76; 95% CI: 1.56, 9.07), and multifocal polyneuropathies (OR=1.72; 95% CI: 1.03, 2.85) compared with focal neuropathies.

The DN4 performed well; however, sensitivity varied by syndrome and the lowest sensitivity was found for trigeminal neuralgia. A positive DN4 was associated with greater pain catastrophizing, disability and anxiety/depression, which may be because of disease severity, and/or these scales may reflect magnification of sensory symptoms and findings. Future research should examine how the DN4 could be refined to improve its sensitivity for specific neuropathic pain conditions.