About 10 to 20% of SIDS cases are believed to be due to channelopathies, which are inherited defects in the ion channels which play an important role in the contraction of the heart.Genetic evidence published in November 2020 concerning the case of Kathleen Folbigg, who is in prison over the death of four of her children, showed that at least two of the children had genetic mutations in the CALM2 gene that predisposed them to heart complications. Alcohol
Drinking of alcohol by parents is linked to SIDS. One study found a positive correlation between the two during New Years celebrations and weekends. Another found that alcohol use disorder was linked to a more than doubling of risk. Other
A 2022 study found that infants who died of SIDS exhibited significantly lower specific activity of butyrylcholinesterase, an enzyme involved in the brains arousal pathway, shortly after birth. This can serve as a biomarker to identify infants with a potential autonomic cholinergic dysfunction and elevated risk for SIDS.SIDS has been linked to cold weather, with this association believed to be due to over-bundling and thus, overheating. Premature babies are at four times the risk of SIDS, possibly related to an underdeveloped ability to automatically control the cardiovascular system.A 1998 report found that antimony- and phosphorus-containing compounds used as fire retardants in PVC and other cot mattress materials are not a cause of SIDS. The report also states that toxic gas cannot be generated from antimony in mattresses and that babies had SIDS on mattresses that did not contain the compound.
The estimate of the percentage of SIDS deaths that are actually infanticide varies from less than 1% to up to 5% of cases.Some have underestimated the risk of two SIDS deaths occurring in the same family; the Royal Statistical Society issued a media release refuting expert testimony in one UK case, in which the conviction was subsequently overturned. Prevention
A number of measures have been found to be effective in preventing SIDS, including changing the sleeping position to supine, breastfeeding, limiting soft bedding, immunizing the infant and using pacifiers. The use of electronic monitors has not been found to be useful as a preventative strategy. The effect that fans might have on the risk of SIDS has not been studied well enough to make any recommendation about them. Evidence regarding swaddling is unclear regarding SIDS. A 2016 review found tentative evidence that swaddling increases the risk of SIDS, especially among babies placed on their bellies or sides while sleeping.Measures not shown to be useful include positioning devices and baby monitors. In the United States, companies that sell the monitors do not have FDA approval for them as medical devices. Sleep positioning
Sleeping on the back has been found to reduce the risk of SIDS. It is thus recommended by the American Academy of Pediatrics and promoted as a best practice by the US National Institute of Child Health and Human Development (NICHD) "Safe to Sleep" campaign. The incidence of SIDS has fallen in a number of countries in which this recommendation has been widely adopted.