Diurnal variation in trauma mortality in sub-Saharan Africa: A proxy for health care system maturity.

BACKGROUND

Globally, traumatic injury is a leading cause of morbidity and mortality in low-income countries. However, trauma centers in these environments have limited resources to manage complex trauma with minimal staffing and diagnostic tools. These limitations may be exacerbated at night. We hypothesized that there is an increase in trauma-associated mortality for patients presenting during nighttime hours.

METHODS

We conducted a retrospective analysis of all patients recorded in the Kamuzu Central Hospital trauma registry in Lilongwe, Malawi from January 2012 through December 2016. Nighttime was defined as 18:00 until 5:59. Patients brought in dead were excluded. A modified Poisson regression model was used to calculate the relationship between presentation at night and mortality, adjusted for significant confounders.

RESULTS

74,500 patients were included. During the day, crude mortality was 0.8% compared to 1.4% at night (p < 0.001). The risk ratio of mortality following night time presentation compared to day was 1.90 (95% CI 1.48, 2.42) when adjusted for injury severity, assessed by the Malawi Trauma Score (MTS), and transfer status. When stratified by the year of traumatic injury, the risk ratio of death decreased each year from 2012-2014 but increased in 2015. There was no difference in 2016.

CONCLUSIONS

We report the first description of diurnal variation in trauma-associated mortality in sub-Saharan Africa. Injured patients who presented at night had nearly twice the adjusted risk ratio of death compared to patients that presented during the daytime although there were yearly differences. Diurnal variation in trauma-associated mortality is a simple but important indicator of the maturity of a trauma system and should be tracked for health care system improvement.