Plasma vitamin C and risk of hospitalisation with diagnosis of atrial fibrillation in men and women in EPIC-Norfolk prospective study

Abstract

Background: Fruit and vegetable intake has been associated with lower risk for cardiovascular risk factors and disease. Data on its association with atrial fibrillation are lacking.

Methods and results: We examined the prospective association of plasma vitamin C concentration as a biomarker for fruit and vegetable intake with the risk of hospitalisation with diagnosis of atrial fibrillation in apparently healthy 8,760 men and 10,530 women aged 39-79 participating in the EPIC-study in Norfolk. The hazard ratios of atrial fibrillation comparing each quartile of plasma vitamin C concentration with the lowest were 0.76 (95% CI 0.57-1.00), 0.73 (95% CI 0.55-0.98) and 0.77 (95% CI 0.58-1.01) in women (p for trend 0.05) and 0.81 (95% CI 0.63-1.03), 0.96 (95% CI 0.76-1.22) and 1.01 (95% CI 0.79-1.28) in men (p for trend 0.66) after adjustment for age, smoking, alcohol consumption, physical activity, systolic blood pressure, diabetes, use of blood pressure medication and body-mass index, with a significant gender × vitamin C interaction (p=0.03). Assuming a linear association, a 20 μmol/l increase in plasma vitamin C concentration (1 standard deviation) was associated with a 13% (95% CI 3-22%) relative reduction in risk of atrial fibrillation in women.

Conclusion: Plasma vitamin C was inversely associated with the risk of atrial fibrillation in women, but there was no such association in men. Our findings suggest that intake of food rich in vitamin C might be preventive for atrial fibrillation with a significant benefit particularly in women with low baseline intake.

Keywords: Atrial fibrillation; Fruit and vegetables; Plasma vitamin C.