Published 13 October 2009, doi:10.1136/bmj.b3666
Cite this as: BMJ 2009;339:b3666

Research

Hazardous cosleeping environments and risk factors amenable to change: case-control study of SIDS in south west England

Peter S Blair, senior research fellow1, Peter Sidebotham, associate professor in child health2, Carol Evason-Coombe, research health visitor1, Margaret Edmonds, research health visitor1, Ellen M A Heckstall-Smith, research assistant1, Peter Fleming, professor of infant health and developmental physiology1

1 Department of Community Based Medicine, University of Bristol, 2 Health Sciences Research Institute, University of Warwick

Correspondence to: P Fleming, FSID Research Unit, St Michael’s Hospital, Bristol BS2 8EG peter.fleming{at}bris.ac.uk

Objectives To investigate the factors associated with sudden infant death syndrome (SIDS) from birth to age 2 years, whether recent advice has been followed, whether any new risk factors have emerged, and the specific circumstances in which SIDS occurs while cosleeping (infant sharing the same bed or sofa with an adult or child).

Design Four year population based case-control study. Parents were interviewed shortly after the death or after the reference sleep (within 24 hours) of the two control groups.

Setting South west region of England (population 4.9 million, 184 800 births).

Participants 80 SIDS infants and two control groups weighted for age and time of reference sleep: 87 randomly selected controls and 82 controls at high risk of SIDS (young, socially deprived, multiparous mothers who smoked).

Results The median age at death (66 days) was more than three weeks less than in a study in the same region a decade earlier. Of the SIDS infants, 54% died while cosleeping compared with 20% among both control groups. Much of this excess may be explained by a significant multivariable interaction between cosleeping and recent parental use of alcohol or drugs (31% v 3% random controls) and the increased proportion of SIDS infants who had coslept on a sofa (17% v 1%). One fifth of SIDS infants used a pillow for the last sleep (21% v 3%) and one quarter were swaddled (24% v 6%). More mothers of SIDS infants than random control infants smoked during pregnancy (60% v 14%), whereas one quarter of the SIDS infants were preterm (26% v 5%) or were in fair or poor health for the last sleep (28% v 6%). All of these differences were significant in the multivariable analysis regardless of which control group was used for comparison. The significance of covering the infant’s head, postnatal exposure to tobacco smoke, dummy use, and sleeping in the side position has diminished although a significant proportion of SIDS infants were still found prone (29% v 10%).

Conclusions Many of the SIDS infants had coslept in a hazardous environment. The major influences on risk, regardless of markers for socioeconomic deprivation, are amenable to change and specific advice needs to be given, particularly on use of alcohol or drugs before cosleeping and cosleeping on a sofa.


This is an open-access article distributed under the terms of the Creative Commons Attribution Non-commercial License, which permits use, distribution, and reproduction in any medium, provided the original work is properly cited, the use is non commercial and is otherwise in compliance with the license. See: http://creativecommons.org/licenses/by-nc/2.0/ and http://creativecommons.org/licenses/by-nc/2.0/legalcode.

Add to CiteULike CiteULike   Add to Complore Complore   Add to Connotea Connotea   Add to Del.icio.us Del.icio.us   Add to Digg Digg   Add to Reddit Reddit   Add to StumbleUpon StumbleUpon   Add to Technorati Technorati    What's this?

Related external webpages:

Listen to a podcast interview with Peter Fleming

This article has been cited by other articles:

  • Mitchell, E. A (2009). Risk factors for SIDS. BMJ 339: b3466-b3466 [Full text]  

Rapid Responses:

Read all Rapid Responses

Suffocation neither simplistic nor unjustified
David G HARPER
bmj.com, 17 Oct 2009 [Full text]
Changing parental high risk behaviour in the reduction of SIDS: the imperative of translational research
Julie Hepworth, et al.
bmj.com, 19 Oct 2009 [Full text]
We should not encourage bed sharing for young infants
Adèle C Engelberts, et al.
bmj.com, 20 Oct 2009 [Full text]
Swaddling and cot death risk
Bregje E. van Sleuwen, et al.
bmj.com, 21 Oct 2009 [Full text]



Access jobs at BMJ Careers
Whats new online at Student 

BMJ