HealthDay News — Adherence to a Mediterranean diet (MedD) is associated with the risk for rheumatoid arthritis (RA) among ever-smoking women, but not among women in general, according to a study published online in Arthritis & Rheumatology.
Yann Nguyen, MD, from the Université Paris-Saclay, and colleagues examined the association between adherence to the MedD and risk for RA in a French cohort. A 9-unit dietary score assessing consumption of vegetables, legumes, cereal products, fish, meat, dairy products, olive oil, and alcohol was used to assess MedD adherence.
The researchers identified 480 incident RA cases among 62,629 women. The MedD score was not associated with RA risk in the whole population (hazard ratio, 0.86; 95% confidence interval, 0.67 to 1.09 for high vs low score; Ptrend = 0.009); among ever-smokers, the MedD score was associated with reduced RA risk (hazard ratio for a 1-point increase, 0.91; 95% confidence interval, 0.84 to 0.99; P = 0.03). The absolute risks for RA were 38.3 and 51.5 per 100,000 person-years in smokers with high and low MedD scores, respectively, compared with 35.8 per 100,000 person-years in never-smokers with high MedD scores.
“We found an inverse association between a high adherence to MedD and the risk of RA only among ever-smoking women, but not among nonsmoking women,” the authors write. “These could be explained by the differences between smokers and nonsmokers in RA pathophysiological mechanisms.”