Introduction. The 2015 dengue outbreak in southern Taiwan caused substantial mortality rates in the elderly. We analyzed here the causes of death among adults with dengue.
Methods. The retrospective study was conducted at a medical center in Tainan from the 1st of August to 31th of December in the year 2015. The detection of the dengue NS1 antigen IgM or viral RNA in patients' blood were used to diagnose dengue. Clinical courses and causes of death were retrieved from chart reviews by two intensivists.
Results. There were 4,488 cases of dengue diagnosed in the study hospital, and these cases had an in-hospital case fatality rate of 1.34% (60 cases). Of these, the mean age was 73 years and gender did not predict outcome. Twenty-eight (46.7%) cases died of severe dengue, and 29 (48.3%) deaths were possibly caused by dengue-related complications, which were mostly secondary infections (24 cases). Most of the families of fatal case (70%) signed do-not-resuscitate (DNR) orders prior to the patients' death. When the dengue epidemic peaked, 13 cardiac arrest events, including out-of-hospital (5 events) and in-hospital (8) cardiac arrests at the emergency department, occurred within four weeks of the dengue epidemic. Notably, in half (7) of these cases, the patients did not search for medical aid prior to experiencing cardiac arrest. Of the 40 cases that had early death (occurring within one week after hospitalization), 60% died of severe dengue. In contrast, 50% of the 20 deaths that occurred later than one week after hospitalization were related to hospital-acquired infections, mainly pneumonia.
Conclusion. The elderly that experience dengue fever may die of severe dengue early or die of secondary infections later. Cardiac arrests can also occur unpredictably at the first aids, which highlight the need of professional and patient education regarding the danger signs that are related to severe dengue in an epidemic setting.