(P03-030-24) Diet Quality Is An Effect Modifier of the Association of Rheumatoid Arthritis With Downstream Cardiovascular Outcomes Among Postmenopausal Women

Objectives: 1.3 million Americans are afflicted with rheumatoid arthritis (RA), a chronic autoimmune disease that especially impacts postmenopausal women. RA patients also have a 1.5-2.5 fold higher incidence of coronary heart disease (CHD) and cardiovascular disease (CVD). While existing studies show that a healthy diet is individually associated with reduced risk of both RA and cardiovascular outcomes, there is a lack of research examining the impact of diet on these related diseases jointly. Thus, this research aimed to evaluate whether diet quality serves as an effect-modifier of the association of RA status with development of downstream cardiovascular outcomes among postmenopausal women.

Methods: RA was defined as a self-report of a physician diagnosis. 99,840 postmenopausal women without baseline RA and 10,494 postmenopausal women with baseline RA were prospectively followed for an average of 8.1 years as part of the Women’s Health Initiative. Diet quality was evaluated using food frequency questionnaires and the Healthy Eating Index 2015. Data was analyzed using multivariable Cox proportional regression with adjustment for income, education, body mass index (BMI), diabetes, hypertension, joint pain, joint swelling, and general health, with age used as a time-to-event variable.

Results: As compared to those with a healthy diet and no RA (Reference Group), those with an unhealthy diet and no RA (Group 1), a healthy diet and RA (Group 2), and an unhealthy diet and RA (Group 3) developed significantly more CVD (p < .0001), CHD (p=0.0068), stroke (p=0.0253), CVD death (p < .0001), and all-cause mortality (p < .0001). The percentages by which downstream cardiovascular outcomes were increased as compared to the Reference Group were as follows: Incident CVD (Group 1: +8.4%, Group 2: +7.6%, Group 3: +15.7%); Incident CHD (Group 1: +7.2%, Group 2: insignificant change, Group 3: +14.0%); Incident stroke (Group 1: +10.1%, Group 2: +17.0%, Group 3: +19.4%); CVD death (Group 1: +9.6%, Group 2: +20.6%, Group 3: +19.9%); All-cause mortality (Group 1: +14.1%, Group 2: +20.0%, Group 3: +30.5%).

Conclusions: Diet quality effect-modifies the association of RA status with downstream cardiovascular outcomes. Specifically, an unhealthy diet is associated with increased development of downstream cardiovascular outcomes in postmenopausal women with and without RA.

Funding Sources: None