Abstract
BACKGROUND: Low QRS voltage has been shown to be associated with increased mortality in the general population and in a small pilot study the combined QRS voltage of ECG leads I and II was found to be associated with in-hospital mortality. HYPOTHESIS: Confirm that low QRS voltage predicts the in-hospital mortality of acutely ill patients, and compare QRS voltage with other predictors of mortality that can be easily, quickly and cheaply obtained at the bedside. METHODS: Prospective observational study of vital signs, QRS voltage and simple tools used to assess mental, functional and nutritional status at the bedside in unselected acutely ill patients admitted to a resource-poor hospital in sub-Saharan Africa. RESULTS: Out of 1486 patients, 77 died (5.2%) in hospital. A combined lead I + II voltage <1.8 mV was present in 789 (53.1%) of patients, and significantly associated with in-hospital mortality (odds ratio 3.6, 95% CI 2.0-6.5, χ(2) 21.2, P < 0.00001). On logistic regression impaired mobility, the National Early Warning Score, male gender and lead I + II voltage were the only independent predictors of mortality. None of the 445 patients who were mobile on admission with a lead I + II voltage ≥ 1.8 mV died in hospital. CONCLUSIONS: Low QRS voltage, male gender, NEWS, and impaired mobility were independent predictors of in-hospital mortality in the study population. These four variables, which are easily obtained at the bedside, could potentially provide a rapid, easy, and cheap risk stratification system.