BioMed Research International / 2019 / Article / Tab 1

Research Article

Independent Influence of Blood Pressure on QTc Interval: Results from a General Chinese Population

Table 1

Characteristics of the study population.

VariableNormal QTcProlonged QTcP value
(n = 9,182)(n = 1,371)

Age, years53.2 ± 10.356.8 ± 10.8< 0.001
Male4,239 (46.2)536 (39.1)< 0.001
Race of Han8,708 (94.8)1,303 (95.0)0.751
BMI, kg/m224.7 ± 3.625.3 ± 3.9< 0.001
SBP, mmHg139.9 ± 22.5152.6 ± 25.5< 0.001
DBP, mmHg81.3 ± 11.386.5 ± 13.0< 0.001
Hypertension4,359 (47.5)982 (71.6)< 0.001
FBG, mmol/L5.84 ± 1.506.31 ± 2.27< 0.001
TC, mmol/L5.21 ± 1.075.40 ± 1.16< 0.001
TG, mmol/L1.59 ± 1.391.97 ± 1.96< 0.001
LDL-C, mmol/L2.90 ± 0.813.05 ± 0.85< 0.001
HDL-C, mmol/L1.41 ± 0.381.40 ± 0.400.441
SUA, mg/dL4.87 ± 1.404.99 ± 1.530.007
Calcium, mmol/L2.32 ± 0.132.34 ± 0.12< 0.001
Potassium, mmol/L4.21 ± 0.344.09 ± 0.38< 0.001
Magnesium, mmol/L0.85 ± 0.110.85 ± 0.080.117
Current smoker3,243 (35.3)474 (34.6)0.590
Current drinker2,073 (22.6)264 (19.3)0.006
LVIDd, cm4.70 ± 0.414.74 ± 0.450.001
IVS, cm0.87 ± 0.120.91 ± 0.14< 0.001
PWT, cm0.85 ± 0.100.88 ± 0.12< 0.001
LVMI, g/m281.1 ± 18.086.5 ± 21.7< 0.001
LVH837 (9.1)251 (18.3)< 0.001
Heart rate, bpm70.3 ± 11.679.9 ± 13.1< 0.001
QTc interval, ms423.3 ± 19.2469.5 ± 18.9< 0.001
History of heart disease†830 (9.0)210 (15.3)< 0.001
Medication used‡4,745 (51.7)870 (63.5)< 0.001

Abbreviations. BMI: body mass index; DBP: diastolic blood pressure; FBG: fasting blood glucose; HDL-C: high density lipid cholesterol; IVS: interventricular septum; LDL-C: low density lipid cholesterol; LVH: left ventricular hypertrophy; LVIDd: left ventricular internal diameter at end-diastole; LVMI: left ventricular mass index; PWT: posterior wall thickness; QTc: QT interval corrected for heart rate with Bazett’s formula; SBP: systolic blood pressure; TC: total cholesterol; TG: triglycerides.
Note. Data are presented as mean ± standard deviation or n (%).
†Including coronary heart disease, arrhythmia, and heart failure.
‡Indicating any self-reported medication used in the past 2 weeks.