Table 1.
Characteristics of NHANES III participants by spatial QRS|T angle.
| QRS|T angle (range) | |||
|---|---|---|---|
| WOMEN | Normal (<90°) (N=2,796) |
Borderline (90° to 120°) (N=751) |
Abnormal (≥121°) (N=243) |
| Age, years | 56.1 (0.4) | 57.1 (0.9) | 60.5 (1.1) |
| Race/ethnicity | |||
| Non-Hispanic white | 86.5% | 88.4% | 83.3% |
| Non-Hispanic black | 9.7% | 8.9% | 14.0% |
| Mexican-American | 3.8% | 2.7% | 2.7% |
| Physically inactive | 28.9% | 32.5% | 36.0% |
| Current smoking | 19.2% | 20.3% | 27.9% |
| Body mass index (kg/m2) | 27.1 (0.2) | 27.3 (0.4) | 28.5 (0.7) |
| Systolic blood pressure (mmHg) | 125.6 (0.5) | 130.5 (1.1) | 136.3 (1.7) |
| Antihypertensive medication use | 19.0% | 23.4% | 38.8% |
| Heart rate (beats per minute) | 68.6 (0.3) | 70.9 (0.6) | 70.7 (1.7) |
| Total cholesterol (mg/dL) | 219.1 (1.1) | 227.0 (2.2) | 228.4 (3.6) |
| High-density lipoprotein cholesterol (mg/dL) |
56.2 (0.6) | 55.9 (0.9) | 53.4 (1.4) |
| Cholesterol-lowering medication use | 4.6% | 4.6% | 8.0% |
| C-reactive protein ≥ 3 mg/L | 38.2% | 40.1% | 49.3% |
| Diabetes mellitus | 5.9% | 11.8% | 18.6% |
| Estimated glomerular filtration rate < 60 ml/min/1.73 m2 |
8.4% | 10.5% | 13.5% |
| Albuminuria ≥ 30 mg/g | 7.5% | 13.6% | 23.5% |
| Prior history of stroke | 1.8% | 1.3% | 5.4% |
| QRS|T angle (range) | |||
|---|---|---|---|
| MEN | Normal (<107°) N=2,348 |
Borderline (107° to 135°) N=711 |
Abnormal (≥136°) N=203 |
| Age, years | 54.7 (0.4) | 55.4 (0.8) | 58.8 (1.4) |
| Race/ethnicity | |||
| Non-Hispanic white | 87.4% | 84.7% | 80.7% |
| Non-Hispanic black | 8.4% | 11.5% | 15.4% |
| Mexican-American | 4.3% | 3.9% | 3.9% |
| Physically inactive | 16.1% | 17.5% | 22.5% |
| Current smoking | 24.6% | 29.9% | 31.1% |
| Body mass index (kg/m2) | 27.3 (0.2) | 27.0 (0.2) | 28.2 (0.5) |
| Systolic blood pressure (mmHg) | 127.7 (0.6) | 131.9 (1.1) | 136.7 (2.3) |
| Antihypertensive medication use | 14.6% | 14.9% | 27.3% |
| Heart rate (beats per minute) | 66.4 (0.4) | 67.3 (0.6) | 69.8 (1.4) |
| Total cholesterol (mg/dL) | 212.5 (1.4) | 214.1 (2.1) | 211.7 (5.9) |
| High-density lipoprotein cholesterol (mg/dL) |
45.3 (0.5) | 45.8 (0.9) | 46.0 (2.1) |
| Cholesterol-lowering medication use | 3.8% | 3.1% | 9.3% |
| C-reactive protein ≥ 3 mg/L | 27.2% | 31.0% | 44.1% |
| Diabetes mellitus | 8.1% | 12.1% | 21.5% |
| Estimated glomerular filtration rate < 60 ml/min/1.73 m2 |
5.0% | 5.8% | 7.6% |
| Albuminuria ≥ 30 mg/g | 7.6% | 13.5% | 23.6% |
| Prior history of stroke | 2.1% | 2.3% | 2.9% |
Numbers in table are mean (standard error) or percentage
The cut-points for normal, borderline, and abnormal represent the 75th (90 to 120 and 107 to 135 for women and men, respectively) and 95th percentiles (≥121 and ≥136 for women and men, respectively) of the spatial QRS|T angle distribution of NHANES III after applying population weights.