Table 1.

Age-standardized prevalence of ECG abnormalities in Lithuanian population aged 40–64 years

Prevalence of ECG abnormalities	Study years				P from chi squared
	1986–1987	1992–1993	1999–2002	2006–2008
Men (n)	1496	926	1119	1886
Q - QS codes, %	4.1	3.8*	2.5*	2.1a	0.002
Left axis deviation, %	4.3*	5.5*	3.3	5.2*	0.048
ST-T codes, %	6.3*	3.8a, *	5.0*	5.1	0.057
High R waves, %	6.3*	5.8*	9.0a, b, *	9.5a, b, *	< 0.001
Arrhythmia, %	5.3	5.9	4.7*	4.4*	0.295
Blocks, %	1.4	1.4*	1.8*	1.8*	0.729
Definite myocardial infarction, %	1.2*	1.0*	0.8*	0.5*	< 0.001
Possible myocardial infarction, %	1.2	1.1	0.7	0.7*
Left ventricular hypertrophy, %	3.1	4.0*	6.3 a, *	5.8 a, *
Ischemia, %	5.9*	4.0*	4.0*	4.7
Marginal abnormalities or absent, %	88.6*	89.8	88.1	88.3*
Women (n)	1609	1114	1415	2339
Q - QS codes, %	3.2	1.8	1.1a	2.1	< 0.001
Left axis deviation, %	2.8	2.8	2.2	2.7	0.696
ST-T codes, %	12.9	7.7a	9.1a	5.9a, c	< 0.001
High R waves, %	4.2	2.7	3.7	3.5	0.233
Arrhythmia, %	4.8	4.2	2.6a	3.1a	0.004
Blocks, %	0.7	0.5	0.6	0.8	0.869
Definite myocardial infarction, %	0.4	0.0	0.2	0.2	< 0.001
Possible myocardial infarction, %	1.4	0.6	0.4a	1.4c
Left ventricular hypertrophy, %	2.6	1.7	2.1	2.2
Ischemia, %	12.3	8.2a	8.4a	5.9a, c
Marginal abnormalities or absent, %	83.2	89.5a	88.9a	90.3a

^ap < 0.05 compared to 1986–1987, Bonferroni test. ^bp < 0.05 compared to 1992–1993, Bonferroni test. ^cp < 0.05 compared to 1999–2002, Bonferroni test. *p < 0.05 compared men to women

ECG: electrocardiogram

Bold typeface of P values indicates significance