Early-life famine exposure and rheumatoid arthritis in Chinese adult populations: a retrospective cohort study

Objective This study aimed to explore the association between famine exposure in early life and the odds of rheumatoid arthritis (RA) in adulthood.Design A population-based retrospective cohort study.Setting China.Participants A total of 111 706 participants (1775 with RA) born from 1956 to 1964 were selected from the baseline survey of a large cohort in China.Primary and secondary outcome measures Four famine exposure groups were generated based on dates of birth, namely prenatal-exposed, infant-exposed, preschool-exposed and non-exposed groups. Logistic regressions were used to explore the association between famine exposure and self-reported RA in adulthood, adjusting for sex, region, monthly income, highest education, alcohol consumption, tobacco use, body mass index (BMI) and metabolic equivalent tasks. Analyses were also performed with stratification for sex (female or male), residing region (urban or rural), famine severity (severe or non-severe) and BMI (≥24 or