Risk Factors for Poor Outcome or Death in Young Children With Respiratory Syncytial Virus-Associated Acute Lower Respiratory Tract Infection: A Systematic Review and Meta-Analysis.

BACKGROUND: Respiratory syncytial virus (RSV)-associated acute lower respiratory tract infection (RSV-ALRTI) constitutes a substantial disease burden in young children. We aimed to identify all studies investigating the risk factors for RSV-ALRTI poor outcome or death in young children. METHODS: We carried out a systematic literature review across 7 databases with data from studies published from January 1995 to December 2019. We defined poor outcome as need for prolonged hospital stay, oxygen supplementation, mechanical ventilation, or intensive care unit admission. The quality of all eligible studies was assessed according to modified Grading of Recommendations, Assessment, Development and Evaluations (GRADE) criteria. We conducted meta-analyses to estimate odds ratios (ORs) with 95% confidence intervals (CIs) for individual risk factors. RESULTS: We identified 27 eligible studies, which investigated 20 risk factors for RSV-ALRTI poor outcome and/or death in children <5 years old, compared with children with RSV-ALRTI who did not have poor outcome or who did not die. Among the risk factors, 6 were significantly associated with RSV-ALRTI poor outcome: any comorbid condition (OR, 2.69; 95% CI, 1.89-3.83), congenital heart disease (3.40; 2.14-5.40), prematurity with gestational age (GA) <37 weeks (1.75 (1.31-2.36), prematurity with GA ≤32 weeks (2.68; 1.43-5.04), age <3 months (4.91; 1.64-14.71), and age <6 months (2.02; 1.73-2.35). The meta-estimate ORs for all risk factors other than age <3 months were based on studies using multivariable analysis. For death, only prematurity with GA <37 weeks had a significant meta-estimated OR-3.81 (95% CI, 1.68-8.63)-based on univariable analysis. CONCLUSIONS: This study represents a comprehensive report of the association between various risk factors and RSV-ALRTI poor outcome or death in young children. More research should be carried out to elucidate risk factors associated with poor outcome or death using multivariable analysis.

Disease Burden Estimates of Respiratory Syncytial Virus related Acute Respiratory Infections in Adults With Comorbidity: A Systematic Review and Meta-Analysis.

BACKGROUND: Respiratory syncytial virus related acute respiratory infection (RSV-ARI) constitutes a substantial disease burden in adults with comorbidities. We aimed to identify all studies investigating the disease burden of RSV-ARI in this group. METHODS: We estimated the incidence, hospitalization rate, and in-hospital case fatality ratio (hCFR) of RSV-ARI in adults with comorbidities based on a systematic review of studies published between January 1996 and March 2020. We also investigated the association between RSV-ARI and any comorbidity in adults. Meta-analyses based on random effects model were carried out. RESULTS: Overall, 20 studies were included. The annual incidence rate of RSV-ARI in adults with any comorbidity was 37.6 (95% confidence interval [CI], 20.1-70.3) per 1000 persons per year in industrialized countries and the seasonal incidence rate was 28.4 (11.4-70.9) per 1000 persons per season. The hCFR in industrialized countries was 11.7% (5.8%-23.4%). There were no studies in developing countries. There were insufficient data to generate the meta-estimate of hospitalization rate. The likelihood of experiencing RSV-ARI for those with any comorbidity compared to those without was estimated to be 4.1 (odds ratio [OR], 1.6-10.4) and 1.1 (OR, 0.6-1.8) from studies using univariable and multivariable analysis respectively. CONCLUSION: The disease burden of RSV-ARI among adults with comorbidity is substantial with limited data available.