Children with special risk medical conditions (SRMC) are over-represented in influenza hospitalizations. A systematic review was undertaken to determine whether children with SRMCs experience greater complications or severity following influenza infection.
Bibliographies of pertinent articles were searched in MEDLINE and EMBASE (1990 to March 2018) and contact made with the investigators of unpublished studies containing relevant data. Studies of children (aged ≤18 years) with a SRMC hospitalized with influenza were included. Outcomes were pneumonia, intensive care unit (ICU) admission, mechanical ventilation, neurologic outcomes (seizures, encephalopathy), death and length of stay in hospital or ICU.
Twenty-two studies met inclusion criteria. Compared with healthy peers, children with SRMC had higher odds of ICU admission [pooled odds ratio (OR) 1.66 (95% confidence interval (CI): 1.25–2.21)], for mechanical ventilation [pooled OR 1.53 (95% CI: 0.93–2.52)] and death [pooled OR 1.34 (95% CI: 0.74–2.41)]. Additionally, children with SRMC were more likely to develop bacterial pneumonia (crude OR 1.7; 95% CI: 1.1–2.6) or experience prolonged hospital length of stay [adjusted rate ratio 1.75 (95% CI: 1.44–2.11)]. The level of GRADE evidence was low for all outcomes considered in this review.
While there was evidence that ICU management and bacterial pneumonia increases in children with SRMC, evidence showing an increase in the probability of death or need for mechanical ventilation was inconsistent. Further research using large datasets should evaluate the impact of complications and associated morbidity from influenza in SRMC children.
From the *Discipline of Paediatrics, Adelaide Medical School
†Robinson Research Institute, The University of Adelaide, South Australia, Australia
‡Central Adelaide Local Health Network, SA Health, South Australia, Australia
§Department of Paediatrics, University of Melbourne, Murdoch Children’s Research Institute (MCRI), Melbourne, Australia
¶Department of General Medicine, Royal Children’s Hospital, Melbourne, Australia
‖Vaccinology and Immunology Research Trials Unit, Women’s and Children’s Hospital, North Adelaide, South Australia, Australia
Accepted for publication May 7, 2019.
The authors have no financial relationships relevant to this article to disclose. No funding was secured for this study. This review was initiated as part of studies toward a Doctor of Philosophy (PhD) undertaken by Ms Tuckerman; funded by an Australian Government Research Training Program Scholarship (formally Australian Postgraduate Award). Prof Marshall is supported by NHMRC Fellowship APP1084951. This review is not sponsored or financed by a third party.
H.M. is an investigator on clinical trials of investigational vaccines sponsored by Industry. Her institution receives funding from Industry (GSK, Pfizer, Novavax) for Investigator led research. She does not receive any personal payments from the Industry. H.M. is a member of the Australian Technical Advisory Group on Immunisation (ATAGI), Australian Government. This paper reports her own personal views and not those of the ATAGI. The other authors have no conflicts of interest to disclose.
Registration: PROSPERO CRD42017074648 web link: http:/www.crd.york.ac.uk/PROSPERO/display_record.php?ID=CRD42017074648
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Address for correspondence: Helen S. Marshall, MD, Robinson Research Institute, University of Adelaide; Vaccinology and Immunology Research Trials Unit (VIRTU), Women’s and Children’s Hospital, 72 King William Rd, North Adelaide, SA 5006, Australia. E-mail: firstname.lastname@example.org.