Insights & Discussion
Fish intake does not majorly impact overall rheumatoid arthritis risk but can lessen the association of smoking for rheumatoid arthritis diagnosed under 55 years of age.
In this study, we evaluated fish intake and its potential impact on rheumatoid arthritis (RA) risk in a sample of 166,013 women, utilizing data from two prospective cohorts, the Nurses' Health Study spanning 1984-2014, and the Nurses' Health Study II spanning 1991-2015. We assessed fish intake using food frequency questionnaires given at the start of the study and every four years following. We determined cases of RA and their serologic status by reviewing medical records. Subsequently, we applied a pooled Cox regression model to estimate hazard ratios for RA relative to fish intake frequency. Additionally, we tested for any interactions between smoking and fish intake concerning RA risk.
In the analysis of our results, during a combined follow-up period resulting in over 3.8 million person-years, we documented 1,080 incident RA cases. Interestingly, we found no significant association between higher fish intake and a reduced risk of RA, whether seropositive or seronegative. However, we observed an elevated risk of RA specifically in cases diagnosed after 55 years of age with an increase in fish intake. In contrast, among women 55 years old or younger, frequent fish intake compared to infrequent consumption was generally associated with a reduced risk of RA. Furthermore, our results indicated that ever-smokers with infrequent fish intake exhibited a significantly higher risk of RA diagnosed 55 years or younger. However, this risk was more modest among ever-smokers with frequent fish intake.
Discover Related Insights
Moderate consumption of fish, particularly oily fish, may decrease rheumatoid arthritis risk, potentially countering the increased risk induced by smoking.
2022 Nutrients Fish Consumption and Risk of Rheumatoid Arthritis: Findings from the E3N Cohort Study Nguyen Y, Salliot C, Mariette X, Boutron-Ruault MC, Seror R
Cohort Study Fish Oils Omega-3 Fatty Acids
The research was carried out within the E3N Study, a French prospective cohort study involving 98,995 women from 1990. Within this group, the diet of the subjects was assessed via validated food frequency questionnaires gathered in 1993. Utilising the colossal amount of data collected, a statistical method known as Cox proportional hazards models were implemented to identify potential relationships between incident rheumatoid arthritis, various types and amounts of fish consumption, and other potential risk factors such as smoking and age.
Looking at the discussion of results, the study unearthed some fascinating links. Starting off, no linear association between general fish consumption and rheumatoid arthritis risk existed. Nevertheless, moderate consumption of fish was found to have a protective effect, reducing likelihood of developing rheumatoid arthritis. Digging deeper, this protection was especially pronounced in current or former smokers. Interestingly, this favorable association seemed to be stronger when it came to consumption of oily fish, thanks to its high omega-3 fatty acid content. Conversely, lean fish consumption did not display the same level of correlation. The proposed theory is the protective influence is likely due to the omega-3 fatty acid content prevalent in oily fish.