Background: Physical activity is associated with a reduced risk of rheumatoid arthritis (RA). However, it remains unclear whether the ‘weekend warrior’ (WW) pattern, characterized by achieving the majority of moderate-to-vigorous PA (MVPA) within 1-2 days, or a more evenly distributed pattern provides any benefits for lowering the risk of incident RA.

Objectives: This study aimed to explore the association of accelerometer-derived WW and other patterns with incident RA, and the potential modifying effect of genetic susceptibility.

Methods: 89,241 participants from the UK Biobank without a prior diagnosis of RA and with a complete week of accelerometer-based physical activity data (collected between 2013 and 2015) were included. Participants were categorized according to guideline-based thresholds: inactive (<150 min/week), active WW (≥150 min/week with ≥50% of total MVPA accrued in 1–2 days), and regularly active (≥150 min/week but not meeting the active WW criteria). A polygenic risk score for RA was used for further assessing the interactions and joint effects of genetic risk and activity patterns. The associations between different activity patterns and incident RA were evaluated using multivariable Cox proportional hazards models, adjusting for potential confounders.

Results: During a mean follow-up of 7.8 years, 675 individuals developed RA. Overall, a nonlinear inverse relationship was observed between total MVPA and incident RA ( P for nonlinearity = 0.003). Compared to inactive group, both the active WW (HR = 0.60, 95% CI, 0.50-0.71) and regularly active (HR = 0.62, 95% CI, 0.50-0.77) group exhibited a similarly reduced risk of RA. When WW and regularly activity were compared directly, there were no statistically significant differences. Similar findings were observed when applying the median MVPA threshold of ≥230.4 min/week. No significant interaction between genetic risk of RA and activity pattern was observed. Moreover, participants with an active WW pattern and low genetic risk had the lowest risk of incident RA (HR = 0.33, 95%CI, 0.23-0.46) compared with inactive individuals with low genetic risk.

Conclusions: Both concentrated MVPA accumulated over 1 to 2 days and evenly distributed physical activity were associated with a reduced risk of developing RA, even in the high and middle genetic risk groups.

REFERENCES: NIL.

Acknowledgments: NIL.

Disclosure of Interests: None declared.