The relation of blood lead and QRS-T angle in American adults

The QRS-T angle is a key ECG predictor for ventricular arrhythmia. Lead has a strong relation with cardiovascular diseases; however, no study has been conducted to investigate the association between lead exposure and QRS-T angle. Thus, we explored this association in a population-based representative sample: NHANES III. We used the standard 12-lead ECGs to calculate Spatial QRS-T angles. Blood lead concentration was measured using graphite furnace atomic absorption spectrophotometry method. We conducted multivariate weighted logistic regression to adjust for impaired fasting glucose, hypertension, poverty index, age, race, and smoking status. We found that when the log of blood lead increased by one unit, the odds of an abnormal QRS-T angle increased by 34% among men and 4% among women. We suggest the use of QRS-T angle deviation among those who are exposed to lead to detect individuals at risk for adverse cardiovascular outcomes such as arrhythmias.