Mediterranean Diet and Incidence of Rheumatoid Arthritis in Women

Abstract

Objective We examined the association between Mediterranean dietary pattern as measured by Alternate Mediterranean Diet Score (aMed) and risk of incident rheumatoid arthritis (RA) in US women. Methods We prospectively followed 83,245 participants from the Nurses’ Health Study (NHS, 1980–2008) and 91,393 participants from NHS II (1991–2009) who were initially free of baseline connective tissue diseases. Dietary information was obtained via validated food frequency questionnaires (FFQ) at baseline and approximately every 4 years during follow-up. The aMed was calculated according to the consumption status of 9 food components using cumulative average value. Time-varying Cox proportional hazards models were used to calculate hazard ratios (HR) for RA, seropositive RA and seronegative RA after adjustment for potential confounding factors. Results from 2 cohorts were pooled by an inverse variance–weighted, fixed-effects model. Results During 3,511,050 person-years of follow-up, 913 incident cases of RA were documented in the two cohorts. After adjustment for several lifestyle and dietary variables, in both cohorts, greater adherence to Mediterranean dietary pattern was not significantly associated with altered risk of RA. The pooled HR for women in the highest quartile of aMed score was 0.98 (95% CI: 0.80–1.20) compared with those in the bottom quartile. Similar non-significant results were observed for both seropositive and seronegative RA. We did not find significant associations between each individual food component (except for alcohol) of aMed score and risk of incident RA. Conclusion We did not find a significant association between Mediterranean dietary pattern and risk of RA in women.

Role of Microbiome in Rheumatic Diseases

“…A recent Japanese study found that the anti-CCP antibody could cross-react with microbial proteins and plants, not only limited to human autoantigens. This observation supports the hypothesis of food or microbes inducing RA via anti-CCP antibody production [1,38,39].…”

Long-term dietary quality and risk of developing rheumatoid arthritis in women

“…43 44 Finally, legumes, nuts and whole grains, which are abundant in dietary fibre and antioxidants may have potential to mitigate the RA risk. 33 In the current study, we have found that the protective effects of higher diet quality on RA risk are strongest among women aged ≤55 years. This result is similar to our previous finding that the positive association between obesity and RA is also restricted among women with RA diagnosed at younger age.…”

“…In our previous study evaluating association of Alternate Mediterranean Diet Score (AMED) with RA risk, we did not observe a significant association of AMED score as well as the fruit and vegetable consumption components with overall RA risk, but did not investigate whether this was associated with earlier onset RA. 33 AMED is the simple sum of nine dichotomised components at median, not including detailed amount of actual dietary intakes. We previously found another AHEI-2010 component, sugar-sweetened beverages, to be linked to increased risk of later onset RA (diagnosed after age 55 years) using different comparison groups from the current study.…”

Relationship Between Fish Consumption and Disease Activity in Rheumatoid Arthritis

“…Total average energy/day was calculated as the sum of average energy/day from all 120 items. Participants reporting extreme total average energy/day (men <800 kcal/day or >4,200 kcal/day, women <600 kcal/day or >3,500 kcal/day) were excluded (n = 10) . Thus, the range of total average energy intake/day was 800–4,200 kcal/day for men, and 600–3,500 kcal/day for women.…”