The clinical characteristics of patients with severe pandemic H1N1 influenza in Sichuan, China.

Objective To explore the clinical characteristics of patients with severe pandemic H1N1 Influenza in Sichuan and risk factors related to patients’ prognosis. Methods We observed 135 severe patients who came to hospitals for pandemic H1N1 Influenza from 12 cities in Sichuan,China,between September 12,2009 to December 14,2009,and described their baseline characteristics,treatment,and outcomes.A stepwise multiple Logistic-regression analysis was used to evaluate the independent predictors of death. Results Of the 135 patients we studied,86 patients were male. The average age was (28.2±19.3)years old,while patients between 19 to 45 years of age accounted for 47.4%. 96 patients(71.1%) presented with fever. 51 patients(37.8%) had comorbid conditions. The most frequent organ dysfunction was seen in lung(71.1%),liver(27.4%)and cardia(24.4%);130 patients(96.3%) had received oseltamivir,26 patients (19.3%) required mechanical ventilation. 12 of the 135 patients died. Compared with the survivors,patients who died were more likely to have a higher age,lower average blood pressure when admitted,more organ dysfunction,and more likely to have cardia or nervous system dysfunction. The nonsurvivors also seemed to have less opportunity to be exposed to neuraminidase inhibitors,and have more demand for mechanical ventilation.The P value were all under 0.05. The multiple Logistic-regression analysis showed the independent predictors of death were the average blood pressure when admitted and the demand for mechanical ventilation .The P value were both under 0.05. The OR value was 0.86(95%CI 0.002-0.936)and 13.86(95%CI 1.146-16.583),respectively. Conclusions For these severe patients with pandemic H1N1 Influenza we study,the male patients are more than female. Most patients are between 19 to 45 years of age. The most frequent organ dysfunction is seen in lung,liver and cardia. The mortality of these patients is 8.9%. Compared with the survivors,patients who died were more likely to have a higher age,lower average blood pressure when admitted,more organ dysfunction,and more likely to have cardia or nervous system dysfunction. The nonsurvivors also seemed to have less opportunity to be exposed to neuraminidase inhibitors,and more demand for mechanical ventilation. The multiple Logistic-regression analysis showed the independent predictors of death are the average blood pressure and the demand for mechanical ventilation. The OR value is 0.86(95%CI 0.002-0.936) and 13.86(95%CI 1.146-16.583) respectively.