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Comparative Study
. 2010 Dec;126(6):e1453-60.
doi: 10.1542/peds.2010-0507. Epub 2010 Nov 22.

Risk factors in children hospitalized with RSV bronchiolitis versus non-RSV bronchiolitis

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Comparative Study

Risk factors in children hospitalized with RSV bronchiolitis versus non-RSV bronchiolitis

Carla G García et al. Pediatrics. 2010 Dec.

Abstract

Background: The trends in hospitalization rates and risk factors for severe bronchiolitis have not been recently described, especially after the routine implementation of prophylaxis for respiratory syncytial virus (RSV) infections.

Objectives: To define the burden of hospitalizations related to RSV and non-RSV bronchiolitis in a tertiary-care children's hospital from 2002 to 2007 and to identify the risk factors associated with severe disease.

Methods: Medical records of patients hospitalized for bronchiolitis were reviewed for demographic, clinical, microbiologic, and radiologic characteristics as well as the presence of underlying medical conditions. Differences were evaluated between children with RSV and non-RSV bronchiolitis, and multivariable logistic regression analyses were performed to identify independent risk factors for severe disease.

Results: Bronchiolitis hospitalizations in children younger than 2 years old (n = 4800) significantly increased from 536 (3.3%) in 2002 to 1241 (5.5%) in 2007, mainly because of RSV infections. Patients with RSV bronchiolitis (n = 2840 [66%]) were younger at hospitalization and had a lower percentage of underlying medical conditions than children hospitalized with non-RSV bronchiolitis (27 vs 37.5%; P < .001). However, disease severity defined by length of hospitalization and requirement of supplemental oxygen, intensive care, and mechanical ventilation was significantly worse in children with RSV bronchiolitis. RSV infection and prematurity, regardless of the etiology, were identified as independent risk factors for severe bronchiolitis.

Conclusions: There was a significant increase in hospitalizations for RSV bronchiolitis from 2002 to 2007. A majority of the children with RSV bronchiolitis were previously healthy, but their disease severity was worse compared with those hospitalized with non-RSV bronchiolitis.

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Figures

FIGURE 1
FIGURE 1
Flow diagram of selection of study patients. From 2002 to 2007, 5233 hospitalizations were attributed to bronchiolitis at Children’s Medical Center Dallas. A total of 92% occurred in children younger than 2 years, and 95% had a viral test performed. Only the first hospitalization was considered for subsequent analysis, which left a total of 4285 unique patients. ICD-9 indicates International Classification of Diseases, Ninth Revision. a Enzyme immunoassay, DFA, or viral cultures. The DFA viral test used in the study detected 7 respiratory viruses (RSV, para-influenza virus 1, 2, and 3, influenza virus A and B, and adenovirus).
FIGURE 2
FIGURE 2
Bronchiolitis hospitalizations at CMCD. A, Bronchiolitis hospitalizations significantly increased from 2002 to 2007. The x-axis represents each study year. The y-axis reflects the total number of hospital admissions and the total number and percentage of bronchiolitis hospitalizations, which significantly increased from 2002 to 2007 (P < .001; χ2 for trends). B, RSV and non-RSV bronchiolitis hospitalizations per year from 2002 to 2007 at Children’s Medical Center Dallas. Although the proportion of children hospitalized with non-RSV bronchiolitis decreased from 2002 to 2007, hospitalizations attributed to RSV significantly increased from 2002 to 2007 (P < .01).
FIGURE 3
FIGURE 3
Monthly distribution of bronchiolitis hospitalizations. The horizontal (x) axis represents the months of the year for RSV (■) and non-RSV bronchiolitis (gray dashed bars) hospitalizations; the vertical axis displays the aggregates for each month (total number of cases identified per month) during the study period.
FIGURE 4
FIGURE 4
Odds ratios (ORs) for risk factors associated with disease severity in bronchiolitis-related hospitalizations. According to multiple logistic and multiple linear regression analyses, the independent significant risk factors associated with disease severity of oxygen, PICU, and intubation requirement and length of hospital stay are those with a P value of <.05. The reference for disease group RSV is non-RSV, for male subjects are female subjects, and for race is white race. The odds of PICU admission and intubation were inversely exponentially related to the weight and age of the patients. Given that the other risk factors are constant, for every increase (decrease) in weight by 1 kg, the odds of PICU admission decrease (increase) by 9.2% (10.2%). Similarly, for every increase (decrease) in age by 1 month, the odds of intubation decrease (increase) by 1.8% (17.9%), respectively. NS indicates not significant.

References

    1. Shay DK, Holman RC, Newman RD, Liu LL, Stout JW, Anderson LJ. Bronchiolitis-associated hospitalizations among US children, 1980–1996. JAMA. 1999;282(15):1440–1446. - PubMed
    1. Boyce TG, Mellen BG, Mitchel EF, Jr, Wright PF, Griffin MR. Rates of hospitalization for respiratory syncytial virus infection among children in Medicaid. J Pediatr. 2000;137(6):865–870. - PubMed
    1. Carroll KN, Gebretsadik T, Griffin MR, et al. Increasing burden and risk factors for bronchiolitis-related medical visits in infants enrolled in a state health care insurance plan. Pediatrics. 2008;122(1):58– 64. - PMC - PubMed
    1. Leader S, Kohlhase K. Respiratory syncytial virus-coded pediatric hospitalizations, 1997 to 1999. Pediatr Infect Dis J. 2002;21(7):629–632. - PubMed
    1. Leader S, Kohlhase K. Recent trends in severe respiratory syncytial virus (RSV) among US infants, 1997 to 2000. J Pediatr. 2003;143(5 suppl):S127–S132. - PubMed

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