Effect of socioeconomic conditions on frequent complaints of pain in children: findings from the UK Millennium Cohort Study

Background Frequent complaints of pain (FCP) are common in high-income countries, affecting about 25% of children, and may have significant adverse consequences including prolonged school absence and disability. Most FCP are unexplained, and the aetiology is poorly understood. This study aimed to identify risk factors for FCP and explore how risk factors explain variation in pain reporting by childhood socioeconomic conditions (SECs). Methods Analysis of the UK Millennium Cohort Study, including 8463 singleton children whose parents provided data throughout the study. At 11 years, mothers were asked whether their child frequently complains of pain. Risk ratios (RR) and 95% CIs for FCP were estimated using Poisson regression, according to maternal education. Other risk factors were explored to assess if they attenuated any association between FCP and SECs. Results 32.3% of children frequently complained of pain. Children of mothers with no educational qualifications were more likely to have FCP than children of mothers with higher degrees (RR 2.06, 95% CI 1.64 to 2.59) and there was a clear gradient across the socioeconomic spectrum. Female sex, fruit consumption, childhood mental health and maternal health measures were associated with childhood FCP in univariable and multivariable analyses. Inclusion of these factors within the model attenuated the RR by 17% to 1.70 (95% CI 1.36 to 2.13). Conclusion In this representative UK cohort, there was a significant excess of FCP reported in less advantaged children that was partially attenuated when accounting for indicators of parental and childhood mental health. Addressing these factors may partially reduce inequalities in childhood FCP.