According to a study published in Alcoholism: Clinical & Experimental Research, there is a link between the presence of sleep problems in early childhood and early alcohol initiation, recognised as a marker for increased risk of alcohol and other substance abuse disorders (drugs, nicotine). According to the researchers, assessing a child's sleep may be a tool for very early prediction of their future addiction problems.

Part of a continuing, multi-year prospective study conducted on a group of 257 boys from high-risk families (the boys were between 3 and 5 years old at the start of the study).