Bed Sharing and the Risk of Sudden Infant Death Syndrome: Can We Resolve the Debate? Vennemann MM, Hense HW, BajanowskiT, Blair P, Complojer C, Moon RY, Kiechl-Kohlendorfer U. Journal of Pediatrics 2012;160(1):44-48.
Reviewed by Maribeth Chitkara
What was the study question?
The main objective of this study was to evaluate the evidence regarding the risks of bed sharing in regard to Sudden Infant Death Syndrome (SIDS). The practice of bed sharing remains controversial, and practice regarding recommendations varies among providers. Acknowledging that SIDS is still the leading cause of death in the post-natal period in developed countries, the authors sought to perform a meta-analysis of case-control studies providing data on bed sharing and SIDS to determine if it is a legitimate risk factor that should be avoided.
How was the study done?
A literature search via PubMed and Medline was performed by two of the authors using subjects: "sudden infant death syndrome", "sudden unexpected death", and "cot death" with "bed sharing" or "co-sleeping". All case-control studies comparing the relationship of bed sharing and SIDS were included from January, 1970 to December, 2009. Selection criteria included: (1) adequate definition of SIDS; (2) autopsies performed in >95% of cases; (3) an appropriate description of SIDS ascertainment in the study population; (4) a clear description of the process of control selection; and (5) sufficient data to calculate odds ratios (OR) and 95% confidenc intervals (CI), or the actual ORs and 95% CIs were provided. Summary ORs from published univariate and multivariate ORs were calculated. Studies were stratified according to parental smoking status, age of infant at time of last sleep regardless of smoking status, and bed sharing as a usual habit versus bed sharing not usual but in the last night.
What were the results?
Eleven case-control studies were included in this study. In the combined analysis, 710/2464 (28.8%) cases and 863/6495 (13.3%) controls bed shared. The summary OR for bed sharing and SIDS was 2.89 (95% CI, 1.99-4.18). Subgroup analysis for maternal smoking and bed sharing found an OR of 6.27 (95% CI 3.94-9.99), whereas for non-smoking mothers the OR was 1.02 (95% CI 0.49-2.12). Calculated ORs for infants who bed shared under the age of 12 weeks was 10.37 (95% CI 4.44-24.21) versus 1.02 (95% CI 0.49-2.12) for older infants. Infants who did not routinely bed share with their parents, but had bed shared on the last night had a higher OR (2.18, 95% CI 1.45-3.28) when compared to those who routinely bed shared (OR 1.42, 95% CI 0.85-2.38).
What are the implications of these findings?
All of the studies included in this meta-analysis found an increased risk of SIDS in infants who bed shared. However, the elevation of risk appears to be less pronounced in older infants as well as those who are not exposed to maternal smoking. Based on these findings, it is still unclear whether bed sharing in general should be discouraged, or if particularly hazardous circumstances should be identified so as to provide targeted anticipatory guidance for families at risk. At a minimum, the authors suggest that families be warned against bed sharing when either parent smokes or when the parent has consumed drugs or alcohol. While not included in the meta-analysis, the authors call attention to more recent studies looking at deaths associated with co-sleeping on unsafe surfaces, such as sofas, and recommend that parents be counseled against such practices. (SLB)