Risk factors include:
(1) male gender
(2) Black or Native American
(3) prematurity
(4) socioeconomic disadvantage
(5) parental substance abuse (smoking, drinking, drugs)
(6) sleeping in the prone position
(7) soft bedding
(8) bed sharing
(9) infection such as an upper respiratory tract infection
(10) genetic factors (polymorphism in the gene for the serotonin transporter promoter region, other)
Additional contributory factors might include:
(1) floppy infant (impaired ability to respond to stimuli)
(2) medications, including those passed in breast milk (with sedation)
(3) asthma or allergies
(4) brainstem neuroanatomic development
