Introduction: Neuropathic low back pain (LBP) is a debilitating phenomenon that significantly impacts quality-of-life (QOL). The painDETECT questionnaire (PD-Q) is a screening tool aimed at distinguishing LBP of nociceptive (NoP) and neuropathic (NeP) origin. Associations between the PD-Q and LBP specific patient-reported outcome measures (PROMs) are yet to be fully established. Differences in the sociodemographic characteristics of patients suffering NeP compared to NoP LBP remain poorly understood. The purpose of this study was to determine the relationship between NeP as assessed by the PD-Q and pain, disability, quality of life and sociodemographic variables.
Methods: A prospective cohort study was conducted involving 665 patients who presented to a tertiary spine clinic with LBP, aged >18years, who completed the PainDETECT questionnaire. Patiejnts were included if they completed at least one of the following: oswestry disability index (ODI), EuroQol Five-Dimensional (EQ-5D) questionnaire or answered question regarding their sociodemographic status.
Results: The NeP group had a higher mean numerical rating scale (7.961.54 vs. 5.762.27, p<0.001) and lower age (5515.6 vs. 5917.8, p<0.05) compared to the NoP group. When confounded for numeral rating score (NRS), analysis of covariance demonstrated an 89.5% higher total ODI score (p<0.001) and 50.5% lower EQ-5D utility score (p<0.001) in the NeP compared to NoP group. Smokers and individuals with a no partner marital status were 2.373 (OR=2.373, 95%C.I.-[1.319-4.266], p<0.01) and 2.384 times (OR=2.384, 95%C.I.-[1.390-4.092], p<0.01) more likely to have NoP rather than NoP LBP respectively. Patients with NeP were also of lower income class compared to patients with NoP (Z=-2.45, p<0.05).
Conclusion: NeP LBP was associated with higher levels of disability and lower QOL. Smokers, individuals with a no partner marital status, and individuals with a lower income class were more likely to suffer NeP rather than NoP LBP. This study carries profound implications for prior LBP research relying solely on scalar measures to assess pain severity. Our findings have illuminated a critical aspect: in patients with elevated NRS, the detrimental impact of characterizing pain as neuropathic underscores the vital need for accurately distinguishing such pain from its NoP counterpart.