High prevalence of fragmented QRS on electrocardiography in Japanese subjects with diabetes irrespective of metabolic syndrome

Abstract

BackgroundFragmented QRS (fQRS) on electrocardiography is a marker of myocardial fibrosis and myocardial scar formation. fQRS has been reported as a reliable predictor of adverse cardiac events in several populations. We investigated the relationship of fQRS with diabetes mellitus (DM) and metabolic syndrome (MetS) in Japanese patients.Material and methodsOur study enrolled a total of 702 subjects (435 without DM and 267 with type 2 DM) who had a routine health checkup at the Hokuriku Health Service Association (Toyama, Japan) in October 2014. Based on MetS and DM status, participants were categorized into one of the following four groups: DM+ MetS + (157 subjects); DM+ MetS - (110 subjects); DM- MetS + (82 subjects); and DM- MetS- (353 subjects). fQRS was assessed using the results of electrocardiography.ResultsThe prevalence of fQRS was statistically higher in patients with DM+MetS+ (36%) and DM+MetS- (36%), than those with DM-MetS+ (18%) or DM-MetS- (9%) (p < 0.001). Significant differences were observed between the fQRS(+) and fQRS(-) groups for age, gender, waist circumference (WC), heart rate, hypertension, HbA1c, TC, MetS, and DM. The area under the receiver-operating curve for traditional risk factors and DM was 0.72 (p=0.0021, 95% confidence interval [CI]: 0.68-0.77), and for traditional risk factors and MetS it was 0.69 (p=0.1478, 95% CI: 0.64-0.73). Patients with DM had more than three-fold higher likelihood of showing fQRS (odds ratio, 3.41; 95% CI, 2.25-5.22; p<0.0001) compared to the reference group without DM, after adjusting for age, gender, dyslipidemia, hypertension, and WC.ConclusionfQRS was observed more frequently in DM than in MetS and control subjects. DM was the most significant determinant for fQRS among MetS and other traditional metabolic risk factors in the general Japanese population.