Late‐Onset Rheumatoid Arthritis and Air Pollution in a Multiethnic Cohort
Authors' conclusion
Exposure to PM and gaseous pollution associates with increased RA incidence after age 65 years, particularly among African American and Latino adults.
Study context
- Population
- California Multiethnic Cohort participants aged ≥65 years (>70% African American and Latino adults) enrolled in Medicare Fee For Service (2001–2018)2,027 incident rheumatoid arthritis (RA)
- Participants
- 42,152 participants
- Exposure
- Higher vs lower exposure to ambient air pollutants
- Outcome
- Incident RA
Methodological detailsmultiethnic cohort, multivariable Cox proportional hazards regression, time-varying exposures from spatiotemporal models
- Multiethnic cohort
- Multivariable Cox proportional hazards regression
- Time-varying exposures from spatiotemporal models
Main finding
As reported in the abstract
RA incidence by air pollutant exposure
Hazard ratio (95% CI)
PM2.5 per 2 μg/m³
1.20(1.16–1.23)
NO2 per 10 μg/m³
1.44(1.35–1.52)
Each row per its own increment, as printed
Observational data: associations, not effects.
Further findings
RA-PM2.5 association by sex (subgroup)
| HR (95% CI) | P value | ||
|---|---|---|---|
| Men | 1.23 (1.15–1.32) | ||
| Women | 1.17 (1.12–1.21) | P for heterogeneity = 0.06 | |
| 0.512Hazard ratio (log scale) |
RA-PM2.5 association by high-risk work (subgroup)
| HR (95% CI) | P value | ||
|---|---|---|---|
| High-risk work | 1.29 (1.18–1.41) | ||
| No high-risk work | 1.16 (1.12–1.21) | P for heterogeneity = 0.04 | |
| 0.512Hazard ratio (log scale) |
- RA-PM2.5 association by high-risk work (subgroup): longest occupation in labor/craftsman work and ≥10 years in ≥1 of 13 industries
Pollutant levels and risk associations by race/ethnicity (subgroup)
- Higher in African American and Latino than in Japanese American and White adults
- P for heterogeneity < 0.05
RA associations with PM2.5 (and NO2) by demographics, smoking, other lifestyle factors (subgroups)
- Did not differ by demographics, smoking, or other lifestyle factors
Original publication
Late‐Onset Rheumatoid Arthritis and Air Pollution in a Multiethnic Cohort. Arthritis Rheumatol. Published 6 April 2026. doi:10.
Composed by AI from the published abstract and checked against it. How Briefs are made →