Sleep problems are a major public-health issue in the United States. In 2006, for example, more than half of 6th to 12th graders reported feeling tired or sleepy, and more than 30 percent reported having problems remaining asleep during the night. A first-of-its-kind study has found a long-term relationship between childhood sleep problems and subsequent alcohol and drug outcomes.
Results will be published in the June 2010 issue of Alcoholism: Clinical & Experimental Research and are currently available at Early View.
"About one in 10 parents/caregivers think that their toddlers, preschoolers, and children have a sleep problem," said Maria M. Wong, associate professor in the department of psychology at, Idaho State University, citing several studies. "The prevalence of problem sleepiness among adolescents and young adults, ages 12 to 25 years, is not only high but also increasing. Some serious consequences include increased risk of unintentional injuries or death, such as car accidents, low academic performance, negative moods, and increased use of alcohol and drugs."
"Sleep and sleepiness problems are important issues in childhood and adolescence," added Tim Roehrs, director of research at the Sleep Disorders and Research Center at the Henry Ford Hospital. "There are emerging data that the prevalence of chronic insomnia in children and adolescents is not that different than that seen in adults. There also are emerging data that there is morbidity associated with insomnia and sleepiness in childhood and adolescence - school and social problems and the data of the present study now add substance problems."
Wong explained that her group's previous work had shown an association between childhood sleep problems and the early onset of substance use in adolescence. "In those studies, overtiredness and having trouble sleeping predicted onset of alcohol, cigarette, and illicit drug use among boys and onset of alcohol use only among girls," she said. "Most of our participants are young adults right now. So we wanted to test for the association between sleep problems and substance problems now that they are older."
For this family study, researchers had secured the participation of 386 adolescents (292 boys, 94 girls). Data on sleep problems and substance use were gathered in six regular waves - at three to five, six to eight, nine to 11, 12 to 14, 15 to 17, and 18 to 20 years of age - as well as in seven annual waves, from ages 11 to 17.
"We found that 'having trouble sleeping' in early childhood, ages three to five, predicted a higher probability of 'having trouble sleeping' in adolescence, ages 11 to 17, which in turn predicted the presence of drug-related problems in young adulthood ages 18 to 21," said Wong. "Overtiredness in early childhood predicted lower response inhibition - that is, having problems inhibiting impulses and behavior - in adolescence, which predicted higher numbers of illicit drugs used. Overtiredness in childhood also directly predicted the presence of binge drinking, blackouts, driving after drinking alcohol, and the number of lifetime alcohol problems in young adulthood."
"As a specialist in sleep and sleep-disorders medicine and also alcoholism and drug abuse," said Roehrs, "I was not surprised by this report. However, I suspect the pediatrician or family-care physician and the lay person may be surprised. Despite some design issues, this study is an important first step in understanding the relation between sleep problems and substance use problems, particularly among adolescents. Previous studies that have reported such a relation are cross-sectional. This is the first prospective study and it is important from that perspective. Secondly, possible mediators of this relation have been identified."
Wong noted that her study does not directly explain why this relationship exists. "Childhood sleep problems appear to have both direct and indirect effects - via sleep trouble and response inhibition in adolescence - on subsequent substance-related outcomes," she said. "Additionally, our previous work showed childhood sleep problems were associated with early onset of alcohol and drug use, which was a well-established risk factor for subsequent alcohol and drug related problems. This suggests a marker of alcohol problems that may be detectable very early in the life course."
"The bottom line is, sleep is important," said Roehrs. "Even if it is not causal for this relation, improving sleep will modify and minimize the risks. In the addicted adult, at least the alcoholic, sleep problems that remain after the initial acute withdrawal are predictive of relapse."
Wong suggested several steps. "First, it is important to increase public awareness of the significance of sleep problems in children, and their potential effect on self-control and later substance use and abuse," she said. "Second, substance abuse prevention and intervention programs need to consider the relationships among sleep problems, self-control, and the increased risk for substance abuse. Third, health care providers may need to become more aware of the potential serious consequences of childhood sleep problems, and provide treatment when sleep disturbances are clinically indicated."