Table 1. Baseline clinical characteristics of the study population (n = 143).

Age (years)	58.9 ± 11.1
Male—n (%)	100 (69.9)
Follow-up period (years)	16.6 ± 5.3
Organic heart disease* - n (%)	21 (14.7)
Hypertension—n (%)	47 (32.9)
Diabetes mellitus—n (%)	33 (23.1)
Dyslipidemia—n (%)	13 (9.1)

Data are presented as mean ± SD or n (%). The follow-up period is a time interval from the baseline ECG recording to the endpoint or the last day of observation.

*Organic heart disease indicates ischemic heart disease, cardiomyopathy, valvular heart disease, and congenital heart disease.