Arthritis and increased risk of cardiovascular disease: is there an interaction with other chronic diseases? A nationwide cohort study.

BACKGROUND

The relationship between arthritis and cardiovascular disease (CVD) remains controversial. This study aimed to investigate whether arthritis constitutes an independent risk factor for CVD and to evaluate its potential synergistic or antagonistic interactions with other chronic conditions in predicting CVD onset.

METHODS

We used China Health and Retirement Longitudinal Study (CHARLS) data (2011-2020). Multivariate Cox regression models were employed to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for associations between arthritis and self-reported physician-diagnosed CVD, cardiac diseases, and stroke. Interaction effects between arthritis and comorbid chronic conditions were assessed via both multiplicative and additive scales.

RESULTS

A total of 14,666 baseline CVD-free participants were included. Compared with participants without arthritis, those with arthritis had increased risks of CVD (HR = 1.10; 95% CI = 1.01-1.19) and stroke (HR = 1.18; 95% CI = 1.04-1.35), but not cardiac diseases (HR = 1.07; 95% CI = 0.98-1.18) in fully adjusted models. Arthritis had antagonistic effects with diabetes/hyperglycemia on CVD risk across both interaction frameworks: a multiplicative scale (HR = 0.69; 95% CI = 0.50-0.95) and an additive scale (relative excess risk of interaction [RERI] = - 0.46, 95% CI = - 0.87 to - 0.06; attributable proportion of interaction [API] = - 2.92, 95% CI = - 6.93 to - 0.18). Arthritis did not significantly interact with other chronic conditions.

CONCLUSION

This study indicates that individuals with arthritis have an increased risk of CVD, particularly stroke. Importantly, the coexistence of arthritis and diabetes/hyperglycemia appears to attenuate CVD risk, highlighting the need for further investigation into the underlying mechanisms driving this antagonistic interplay.