Adolescents who get poor or insufficient sleep may be at higher risk of developing alcohol and drug problems, scientists say.
Researchers have found that sleep difficulties and hours of sleep can predict a number of specific problems, including binge drinking, driving under the influence of alcohol, and risky sexual behaviour.
"Among normal adults, sleep difficulties and insomnia have predicted onset of alcohol use one year later, and increased risk of any illicit drug use disorder and nicotine dependence 3.5 years later," said Maria M Wong, professor and director of experimental training in the department of psychology at Idaho State University.
"Among adult alcoholics who received treatment for alcohol dependence, those with insomnia at baseline were more likely to relapse to alcohol use.
"The association between poor sleep and substance use has also been found in younger age groups. Overtiredness in childhood has predicted lower response inhibition in adolescence, which in turn predicted number of illicit drugs used in young adulthood.
"Overtiredness in childhood has also directly predicted the presence of binge drinking, blackouts, driving after drinking alcohol, and number of lifetime alcohol problems in young adulthood.
"The purpose of this study was to examine whether sleep difficulties and hours of sleep prospectively predicted several serious substance-related problems that included binge drinking, driving under the influence of alcohol, and risky sexual behaviour," Wong said.
Wong and her co-authors analysed data collected via interviews and questionnaires from 6,504 adolescents (52 per cent girls, 48 per cent boys) participating in the National Longitudinal Study of Adolescent Health in the US.
Data were collected for three waves - 1994-1995, 1996, and 2001-2002 - and study authors used sleep difficulties from a previous wave to predict substance-related problems at a subsequent wave, while controlling for substance-related problems at the previous wave.
"Sleep difficulties at the first wave significantly predicted alcohol-related interpersonal problems, binge drinking, gotten drunk or very high on alcohol, driving under the influence of alcohol, getting into a sexual situation one later regretted due to drinking, and ever using any illicit drugs and drugs-related problems at the second wave," said Wong.
"Previous studies on adolescents were mostly drawn from high risk samples," said Wong.
"This study has added to the existing literature by establishing the relationship between two sleep variables - sleep difficulties and hours of sleep - and the odds of serious alcohol- and drug-related problems in a nationally representative sample," she said.
The study will be published in the journal Alcoholism: Clinical & Experimental Research.