Clinical characteristics and outcome of patients with pandemic 2009 Influenza A(H1N1)v virus infection admitted to hospitals with different levels of health-care.

BACKGROUND

The outcome of patients with influenza A 2009 (H1N1)v virus infection taking into account hospital type has not been elucidated.

OBJECTIVE

To compare risk factors, clinical features and outcome of patients admitted to 3 public hospitals with different levels of health-care.

METHODS

Prospective study of all non-pregnant adult patients admitted to 3 hospitals with pandemic H1N1 infection, from June 1 to December 31 and followed up until 1 month after discharge.

RESULTS

During the study period, 111 patients with a mean age of 49 years (15-89) were hospitalized: 52 in hospital 1 (900-bed tertiary-teaching-hospital), 33 in hospital 2 (315-beds secondary-hospital) and 26 in hospital 3 (150-beds primary-care-hospital).Overall 80% of patients had at least 1 comorbid condition with no differences between hospitals. Symptoms or signs on admission were similar except for cough (P=0.01) more frequent in patients in hospital 1 and dyspnea (P=0.05), myalgia, arthralgia (P=0.04) and hypoxemia (P=0.009) present in more patients in hospital 2. In-hospital mortality rates were not statistically different between hospitals. In the stepwise analysis, independent predictors of mortality were pneumonia on admission (adjusted OR=8.68, 95%CI 1.0-82.43) and cardiac complications during hospitalization (adjusted OR=13.2, 95%CI 1.67-103.98).

CONCLUSIONS

Mortality of patients with pandemic H1N1 infection was influenced by patients underlying conditions, severity of disease (pneumonia) on admission and complications during hospitalization. Hospital-characteristics do not appear to have influenced severe outcome.