Descriptive analysis of mortality predictors in H1n1 influenza in south Indian patients

Background: H1N1 (hemagglutinin-H-neuroaminidase-N) influenza infection is associated with high morbidity and mortality because of associated complications and related factors. Predictors of mortality in H1N1 patients are studied with very few without seasonal/pandemic declaration. This study was carried out to describe the clinical features, complications and different risk factors that affect the outcome in the patients with confirmed H1N1influenza infection. Methods: A retrospective study was done in Kasturba Medical College Hospital, Manipal, India by analyzing the medical records of 141 patients admitted from January, 2011 to June, 2015. Results: Of the 141 patients in the study, 51.1% of the patients were female with a mean age of 32±16.2 years. Fever with headache was observed in 92.9% patients while cough in 78.7% patients and breathlessness in 54.6% patients. On the basis of disease severity, 53.2% of the patients were put on mechanical ventilation. For all the patients, treatment for influenza management began with oseltemivir. Diuretics, anti-anxiety and corticosteroids were given as supportive and symptomatic care which contributed to high mortality in hospitalized patients. Mean hospitalization period was 8.5 days. During the hospitalization, patients developed different complications i.e. 31.20% patients developed respiratory tract infections, while 17.7% patients developed ARDS and 14.4% patients developed sepsis. The mortality rate of this study population was found to be 29.1 %. Conclusion: It was observed that low oxygen saturation during admission, high blood urea level, use of diuretics, corticosteroids, anti-anxiety drugs and complications like ARDS, sepsis influence the mortality rate of patients with H1N1 infection.