The Social Gradient of Pain in Europe: Income‐Related Inequities and the Modifying Role of Osteoarthritis

ABSTRACT Background Bodily pain is a frequent, disabling, and socially patterned population health burden. Although socioeconomic inequalities in pain have been described in Europe, it remains unclear whether this gradient changes in the presence of highly prevalent musculoskeletal conditions such as osteoarthritis. Methods We conducted a cross‐sectional study using anonymized EHIS Wave 3 microdata from 2018 to 2020. The final sample included 278,250 adults from 30 European countries. Bodily pain in the past 4 weeks was analysed as a binary outcome. Household income quintile was the main exposure and self‐reported osteoarthritis the effect modifier. Adjusted prevalence ratios were estimated using robust Poisson regression with an income‐by‐osteoarthritis interaction. Adjusted probabilities, the Relative Index of Inequality, the Slope Index of Inequality, and between‐country heterogeneity were also estimated. Results The weighted prevalence of pain was 55.04%. The income‐by‐osteoarthritis interaction was significant, χ 2 (4) = 135.00; p < 0.001. Among adults without osteoarthritis, higher income was associated with lower pain prevalence (Q5 vs. Q1: aPR = 0.909; 95% CI: 0.893–0.925), whereas osteoarthritis was associated with substantially higher pain prevalence (aPR = 1.392; 95% CI: 1.370–1.413). Without osteoarthritis, the RII was 1.125 and the SII was 4.75 percentage points; with osteoarthritis, the RII was 0.964 and the SII was −2.21 percentage points. Between‐country heterogeneity was significant, χ 2 (29) = 348.99; p < 0.001. Conclusions Bodily pain affects more than half of European adults and follows an income‐related pattern. Osteoarthritis modifies this inequality: without osteoarthritis, pain follows a classic socioeconomic gradient, whereas with osteoarthritis, pain remains highly prevalent across income groups and the gradient is attenuated or slightly reversed. Significance Statement This study demonstrates that income‐related inequalities in recent bodily pain vary according to self‐reported osteoarthritis status across 30 European countries. Its main contribution is to show that a high prevalence of pain in people reporting osteoarthritis may attenuate or obscure conventional socioeconomic gradients when pain is measured as a binary outcome. These findings highlight the limitations of relying exclusively on pain presence to characterize socioeconomic inequalities and support further investigation of pain severity and functional consequences.