Electrocardiographic findings and conduction parameters
| Findings, classified according to the Minnesota method | Exposed group (n = 203) % | Control group (n = 94) % | Difference* | 95% CI† |
|---|---|---|---|---|
| *Difference between the percentages. | ||||
| †95% confidence interval for the differences between the percentages. | ||||
| Q and QS patterns | 0.5 | 3.3 | −2.8 | −6.6 to1.0 |
| QRS axis deviation | 2.5 | 1.1 | 1.4 | −1.6 to 4.4 |
| High amplitude R waves | 21.2 | 23.9 | −2.7 | −13.1 to 7.7 |
| T wave items | 0.5 | 2.2 | −1.7 | −4.9 to 1.5 |
| A-V conduction defect | 3.9 | 1.1 | 2.8 | −0.6 to 6.2 |
| Ventricular conduction defect | 1.5 | 6.5 | −5.0 | −10.3 to 0.3 |
| Arrhythmias | 8.4 | 9.8 | −1.4 | −8.6 to 5.8 |
| S-T segment increase | 3.9 | 2.2 | 1.7 | −2.3 to 5.7 |
| Conduction parameter | ||||
| PR time (ms) | ||||
| Mean (SD) | 164(24) | 165(23) | ||
| QRS time (ms) | ||||
| Mean (SD) | 98(11) | 99(9) | ||
| QTc time (ms) | ||||
| Mean (SD) | 407(19) | 411(17) | ||
| QT time (ms) | ||||
| Mean (SD) | 418(39) | 418(34) | ||
| Heart rate/minute | ||||
| Mean (SD) | 59(10) | 60(11) | ||