Trends in bronchiolitis hospitalizations in the United States, 2000-2009

Abstract

Objective: To examine temporal trend in the national incidence of bronchiolitis hospitalizations, use of mechanical ventilation, and hospital charges between 2000 and 2009.

Methods: We performed a serial, cross-sectional analysis of a nationally representative sample of children hospitalized with bronchiolitis. The Kids Inpatient Database was used to identify children <2 years of age with bronchiolitis by International Classification of Diseases, Ninth Revision, Clinical Modification code 466.1. Primary outcome measures were incidence of bronchiolitis hospitalizations, mechanical ventilation (noninvasive or invasive) use, and hospital charges. Temporal trends were evaluated accounting for sampling weights.

Results: The 4 separated years (2000, 2003, 2006, and 2009) of national discharge data included 544 828 weighted discharges with bronchiolitis. Between 2000 and 2009, the incidence of bronchiolitis hospitalization decreased from 17.9 to 14.9 per 1000 person-years among all US children aged <2 years (17% decrease; P(trend) < .001). By contrast, there was an increase in children with high-risk medical conditions (5.9%-7.9%; 34% increase; P(trend) < .001) and use of mechanical ventilation (1.9%-2.3%; 21% increase; P(trend) = .008). Nationwide hospital charges increased from $1.34 billion to $1.73 billion (30% increase; P(trend) < .001); this increase was driven by a rise in the geometric mean of hospital charges per case from $6380 to $8530 (34% increase; P(trend) < .001).

Conclusions: Between 2000 and 2009, we found a significant decline in bronchiolitis hospitalizations among US children. By contrast, use of mechanical ventilation and hospital charges for bronchiolitis significantly increased over this same period.

Keywords: bronchiolitis; hospital charge; hospitalization; incidence; mortality; trends.

FIGURE 1

Incidence rates of US bronchiolitis hospitalizations per 1000 children according to age group and different definitions, 2000–2009. Overall, there was a decrease in the incidence rate of bronchiolitis hospitalization (17% decrease; P_trend < .001) between 2000 and 2009. Similarly, there was a decrease in the incidence rate in children aged <12 months (21% decrease; P_trend < .001), cases with primary diagnosis of bronchiolitis aged <12 months without high-risk medical conditions (29% decrease; P_trend < .001), cases with bronchiolitis as the primary diagnosis (18% decrease; P_trend < .001), and cases with no high-risk medical conditions (24% decrease; P_trend < .001). By contrast, the incidence rate among children from 12 months to 23 months increased (13% increase; P_trend < .001).

FIGURE 2

In-hospital health care utilization and hospital charges for US children with bronchiolitis, 2000–2009. Between 2000 and 2009, there was a significant decline in the use of intravenous antibiotics (40% decrease; P_trend = .009) and chest radiograph (66% decrease; P_trend = .010), whereas use of mechanical ventilation increased (21% increase; P_trend = .008). The geometric mean of hospital charges per case increased significantly (34% increase; P_trend < .001), adjusted for inflation.