Does the "hispanic paradox" occur in rheumatoid arthritis? Survival data from a multiethnic cohort

Objective Despite lower socioeconomic status (SES) and higher disease burden, Hispanics in the US paradoxically display equal or lower mortality on average than non-Hispanic whites. Our objective was to determine if the "Hispanic paradox" occurs among patients with rheumatoid arthritis (RA). Methods In a cohort of 706 RA patients, we compared differences in RA severity and comorbidity between Hispanic and non-Hispanic white ethnic groups at baseline. Cox proportional hazards models were used to estimate and compare mortality risk between Hispanics and non-Hispanic whites. Results We studied 706 patients with RA, of whom 434 were Hispanic and 272 were non-Hispanic white. Hispanics had significantly lower SES, greater inflammation, as well as higher tender and swollen joint counts. Patients were observed for 6,639 patient-years, during which time 229 deaths occurred by the censoring date (rate 3.4 per 100 person-years; 95% confidence interval 3.0, 3.9). Age- and sex-adjusted mortality was not significantly different between the 2 ethnic groups (hazard ratio [HR] 0.96). After adjustment for comorbidities, RA severity, and level of acculturation, mortality among Hispanics was lower (HR 0.56, P = 0.004). Conclusion Despite greater severity in most clinical manifestations and lower SES among Hispanics, paradoxically, their mortality was not increased. Further research is needed to understand the mechanisms underlying this survival paradox.