Excessive dietary sodium intake augments long-term risk of atrial fibrillation in older adults with hyperglycemia: A community-based prospective cohort study

Studies investigating the association between sodium intake and new-onset atrial fibrillation (AF) have come to controversial results. This study aimed to assess the effect of excessive sodium intake on new-onset AF in individuals with hyperglycemia. Between April 2007 and November 2011, 2841 community-dwelling individuals aged 60 years and older were recruited from the Shandong area, China. Dietary sodium intake was estimated using 24-hour urine collection within seven consecutive days. Fasting plasma glucose (FPG) and glycated hemoglobin (HbA1c) were assessed. New-onset AF was diagnosed using ICD-10 with codes I48 (I48.0 – I48.9) during follow-up. The findings were that excessive sodium intake significantly and independently increased the risk of new-onset AF in older adults with hyperglycemia: hazard ratio (HR) 1.525 [95% confidence interval 1.147;2.029] adjusted P = 0.004. The risk of new-onset AF increased by 29.3% (HR 1.293 [1.108;1.509] adjusted P = 0.001) with a one-standard deviation increase in sodium intake. Excessive sodium intake synergistically interacted with hyperglycemia on the increased risk of new-onset AF (HR 1.599 [1.342;1.905] adjusted P < 0.001 for FPG and HR 1.516 [1.271;1.808] adjusted P < 0.001 for HbA1c). Our findings indicate that excessive sodium intake independently enhances the risk of new-onset AF among patients with hyperglycemia. A sodium-restricted diet may perhaps result in a multiplier effect on reducing the risk of new-onset AF.