Second hand smoke exposure and the risk of invasive meningococcal disease in children: systematic review and meta-analysis
Rachael L Murray*, John Britton and Jo Leonardi-Bee
* Corresponding author: Rachael L Murray
Author Affiliations
Division of Epidemiology and Public Health, University of Nottingham, Clinical Sciences Building Phase 2, Nottingham City Hospital, Hucknall Road, Nottingham, NG5 1PB, UK
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BMC Public Health 2012, 12:1062 doi:10.1186/1471-2458-12-1062
The electronic version of this article is the complete one and can be found online at:
http://www.biomedcentral.com/1471-2458/12/1062
Received: 4 April 2012
Accepted: 22 November 2012
Published: 10 December 2012
? 2012 Murray et al.; licensee BioMed Central Ltd.
This is an Open Access article distributed under the terms of the Creative Commons Attribution License (
http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Abstract
Background
Invasive meningococcal disease remains an important cause of serious morbidity and mortality in children and young people. There is a growing body of literature to suggest that exposure to passive smoke may play a role in the development of the disease, therefore we have performed a systematic review to provide a comprehensive estimate of the magnitude of this effect for smoking by any household member, by individual family members, and of maternal smoking before and after birth.
Methods
Four databases (Medline, Embase, PsychINFO and CAB Abstracts database) were searched to identify studies (to June 2012) and reference lists scanned for further studies. Titles, abstracts and full texts were checked for eligibility independently by two authors. Quality of included studies was assessed using the Newcastle-Ottawa Scale. Pooled odds ratios (OR) with 95% confidence intervals (CI) were estimated using random effect models, with heterogeneity quantified using I2.
Results
We identified 18 studies which assessed the effects of SHS on the risk of invasive meningococcal disease in children. SHS in the home doubled the risk of invasive meningococcal disease (OR 2.18, 95% CI 1.63 to 2.92, I2 = 72%), with some evidence of an exposure-response gradient. The strongest effect was seen in children under 5 years (OR 2.48, 95% CI 1.51 to 4.09, I2 = 47%). Maternal smoking significantly increased the risk of invasive meningococcal disease by 3 times during pregnancy (OR 2.93, 95% CI 1.52-5.66) and by 2 times after birth (OR 2.26, 95% CI 1.54-3.31).
Conclusions
SHS exposure, and particularly passive foetal exposure to maternal smoking during pregnancy, significantly increases the risk of childhood invasive meningococcal disease. It is likely that an extra 630 cases of invasive meningococcal disease annually in children under 16 are directly attributable to SHS exposure in UK homes.
Keywords:
Second hand smoke; Environmental tobacco smoke; Invasive meningococcal disease; Systematic review; Meta-analysis
