Objectives: The aim of this investigation was to identify risk factors for being found with the head covered in sudden infant death syndrome cases and determine whether head covering was likely to be an agonal event or potentially part of the causal pathway in some cases. By using the data from 2 sudden infant death syndrome case-control studies, consistency of the findings could be assessed.
Methods: Two case-control studies were assessed: (1) the New Zealand Cot Death Study (1987-1990, 393 sudden infant death syndrome cases) and (2) a German SIDS case-control study (1998-2001, 333 sudden infant death syndrome cases).
Results: The proportion of sudden infant death syndrome cases in which infants were found with their head covered was 15.6% in the New Zealand study and 28.1% in the German study. Being found with head covering was associated with older infant age. In both studies, being found with head covering was associated with being very sweaty when found. Head covering was also associated with the incidence and severity of thymic petechiae in both studies. Both the position in which the child was placed to sleep and the position in which the child was found were not associated with head covering.
Conclusions: The finding that sudden infant death syndrome cases in which infants were found with their heads covered were often very sweaty suggests that head covering was not an agonal event and that it preceded the death and may have been causally related to the death. Infants who were found with their head covered were older, which probably reflects motor development.