HbA1c and atrial fibrillation: a cross-sectional study in Japan

The aim of the present study was to investigate whether the prevalence of atrial fibrillation (AF) is associated with the level of glycated hemoglobin (HbA1c) in Japanese adults in Kurashiki-city.

Adult residents (≧ 40 years old) were examined twice, in 2006 and 2007. Electrocardiography was conducted to determine the presence of AF. After categorizing all participants into two groups (HbA1c <6.5% as low group and ≧ 6.5% as high group), factors independently associated with the prevalence of AF were investigated in total cohort, low and high groups using multivariate logistic regression analysis.

Of the total 52,448 participants (median age, 72 years; range, 65-78 years; 17,980 men), AF prevalence was 2.2% (1161/52,448). After classifying all participants by HbA1c level, the proportion of participants with AF was 2.2% (1073/49,498) in the low group and 3.0% (88/2950) in high group (p=0.005). AF was significantly associated with cardiac disease (OR, 5.78; 95%CI, 5.07-6.58; p<0.001), elevating HbA1c (OR, 1.57; 95%CI, 1.33-1.84; p<0.001), increasing age (OR, 1.40; 95%CI, 1.30-1.51; p<0.001), and male sex (OR, 1.27; 95%CI, 1.10-1.47; p=0.001) in low group and was related to cardiac disease (OR, 4.85; 95%CI, 3.08-7.62; p<0.001) and age (OR, 1.45; 95%CI, 1.09-1.93; p=0.010) in high group. After adjusted age, gender, vascular risk factors, cardiac disease, and eGFR, elevating HbA1c (OR, 1.18; 95%CI, 1.09-1.28; p<0.001) was the factor in association with AF.

The presence of AF appears to be associated with the level of HbA1c, especially in patients with HbA1c <6.5%.