. Author manuscript; available in PMC: 2015 Nov 18.

Published in final edited form as: J Am Coll Cardiol. 2014 Nov 10;64(20):2111–2119. doi: 10.1016/j.jacc.2014.08.039

Table 1.

Baseline Characteristics for All Patients and After Stratification by QT_corr Percentiles

	Total	QT_corr <5^th (300–383 ms)	QT_corr 20^th to <50^th (383–409 ms)	QT_corr 50^th to <95^th (410–440 ms)	QT_corr ≥ 95^th (441–503 ms)	p value

Age, years	61.7 ± 10.14	61.8 ± 10.8	61.7 ± 10.2	61.8 ± 10.0	61.3 ± 9.9	0.877

Sex, % Female	53.4	42.9	56.1	52.0	52.7	<0.001

Race, %
Caucasian	38.3	32.1	39.0	38.5	36.2
African American	27.5	34.5	26.5	27.3	30.0	0.241
Chinese American	12.0	11.8	12.0	12.2	10.8
Hispanic	22.2	21.6	22.5	22.0	23.0

Hypertension, %	43.8	32.4	38.5	47.3	56.5	<0.001

Participants on antihypertensive medications, %	36.0	32.4	31.7	38.1	46.5	<0.001

Systolic blood pressure, mm Hg	126.3 ± 21.45	122.4 ± 21.17	123.8 ± 20.40	127.9 ± 21.43	132.1 ± 23.91	<0.001

Heart rate, beats/min	63.1 ± 9.59	59.4 ± 9.93	63.7 ± 9.19	62.7 ± 9.58	63.6 ± 10.62	<0.001

Diabetes, %	11.1	10.5	10.5	10.6	15.5	0.007

Family history of heart disease, %	42.6	40.9	43.2	42.4	41.7	0.811

Current Smoking, %	13.1	12.2	12.4	12.5	18.7	0.001

QRS duration, ms	91.4 ± 9.66	88.4 ± 9.54	90.1 ± 9.49	92.7 ± 9.43	92.9 ± 10.25	<0.001

QT duration, ms	410.7 ± 30.25	383.3 ± 24.55	397.8 ± 23.87	422.1 ± 26.53	429.2 ± 38.07	<0.001

QT_b duration, ms	417.2 ± 20.61	377.5 ± 13.95	406.5 ± 11.33	427.5 ± 13.24	437.2 ± 27.35	<0.001

QT_corr duration, ms	410.7 ± 17.79	374.1 ± 9.38	399.6 ± 6.89	421.3 ± 8.08	451.2 ± 10.93	<0.001

QT_fr duration, ms	414.8 ± 18.9	377.4 ± 11.2	403.9 ± 9.1	425.3 ± 10.4	433.9 ± 25.7	<0.001

Height, cm	166.2 ± 10.04	166.7 ± 10.13	165.9 ± 10.0	166.7 ± 10.0	165.2 ± 10.31	<0.001

Weight, lbs	172.8 ± 38.16	163.8 ± 35.16	169.9 ± 37.31	176.0 ± 38.14	176.2 ± 41.28	<0.001

Body mass index, kg/m²	28.3 ± 5.47	26.63 ± 4.75	27.9 ± 5.37	28.7 ± 5.43	29.2 ± 6.07	<0.001

Low-density lipoprotein cholesterol, mg/dL	117.6 ± 31.43	115.23 ± 33.05	117.8 ± 31.28	117.7 ± 31.26	116.9 ± 31.96	0.532

High-density lipoprotein cholesterol, mg/dL	51.1 ± 14.81	52.4 ± 16.38	51.4 ± 14.96	50.5 ± 14.46	51.1 ± 14.79	0.054

Aspirin, %	31.0	31.1	30.9	31.2	30.0	0.932

Statins, %	14.4	15.2	14.8	14.1	14.1	0.866

Education (Graduate) %	17.8	21.3	18.5	17.7	13.5	<0.001

QT_corr = QT interval corrected for R-R interval, race, age and sex; QTb = QT corrected using Bazett formula; QTfr = QT interval corrected using the Framingham formula.