Rheumatoid arthritis (RA) is associated with increased arterial dysfunction and increased risk of cardiovascular disease. Regular fruit and vegetable consumption prevents cardiovascular disease, but their influence on arterial dysfunction in RA has not been investigated. We assessed the relationship between daily fruit-vegetable consumption and arterial dysfunction in this high-risk group.
Participants were recruited from a consecutive series of RA patients aged 40-65 years without overt cardiovascular disease attending rheumatology clinics. Standardised research nurse assessment included SphygmoCor pulse wave analysis using radial applanation tonometry (a higher augmentation index (AIX%) indicates arterial dysfunction), fasting blood sample, patient questionnaire and medical record review. Multivariable analysis was used to adjust for age, sex, cholesterol, mean arterial blood pressure, smoking habit, alcohol consumption, physical activity, cumulative inflammatory burden, rheumatoid nodules, disability and education.
We recruited 114 RA patients: 81% female, mean age 54 years, median arthritis duration 10 years and mean AIX% 31.5 (s.d. 7.7). Fruit and vegetable consumption were significantly correlated (Spearman's rho 0.54, P≪0.0001) and on unadjusted analysis daily fruit and vegetable consumption was associated with a lower AIX% (-3.2; 95% CI -6.4 to -0.1, P=0.05). On adjusted analysis AIX% was lower with daily vegetable (-4.2; 95% CI -7.9 to -0.5; P=0.003), but not with daily fruit (-0.02; 95% CI -3.9 to 3.8; P=0.99) consumption.
Daily vegetable consumption, but not daily fruit consumption, was independently associated with more favourable arterial function in patients with RA. These findings are consistent with the enterosalivary circulation of nitrate having an influence on arterial function.