Chronic Pain Features Relate to Quality of Life More than Physiopathology: A Cross‐Sectional Evaluation in Pain Clinics

Objective To compare the impact of chronic pain physiopathology on health‐related quality of life (HR‐QoL), considering the influence of pain features and psychosocial adjustment (intensity, interference, psychological comorbidities, and sleep quality). Design A cross‐sectional study involving 1,025 noncancer patients with predominantly neuropathic, nociceptive, or mixed chronic pain conditions was conducted in 88 pain clinics within Spain. The EuroQol‐5 Dimensions instrument (EQ‐5D) was used to measure HR‐QoL. The Brief Pain Inventory (BPI), Hospital Anxiety and Depression Scale (HADS), and sleep scale developed for the MOS study (MOS‐SQ) were used to measure pain features and psychosocial adjustment. Multivariate analyses were used to model HR‐QoL measures. Results All patients reported very low HR‐QoL. The mean EQ‐5D index scores were 0.33, 0.36, and 0.37 in the mixed, neuropathic, and nociceptive pain groups, respectively. The differences did not reach statistical significance (P = 0.057). Patients with nociceptive pain had less pain (least pain intensity score: 4.7 vs. 5.2 in the other groups; P = 0.006), less interference with daily activities (BPI average interference score: 6.3 vs. 6.6 and 6.7 in the neuropathic and mixed pain groups, respectively; P = 0.013), less anxiety (HADS score: 8.5 vs. 9.6 and 9.7 in the same respective groups; P = 0.001), and fewer sleep problems (MOS‐SQ sleep problems index: 46.8 vs. 52.2 and 50.2 in the same respective groups; P = 0.005). In the adjusted analyses, HR‐QoL measures were explained by pain intensity, anxiety, and sleep quality, but not by physiopathological pain type. Conclusions Pain features, particularly intensity, have a greater impact than pain physiopathology on HR‐QoL. Distinct physiopathological mechanisms give rise to different pain features that, in turn, may mediate the HR‐QoL of patients with chronic pain. This could be used to improve pain management strategies.