A University Herald report quotes researcher Christian L Nicholas, National Health & Medical Research Council Peter Doherty Research Fellow in the Sleep Research Laboratory at the University of Melbourne as saying: "People likely tend to focus on the commonly reported sedative properties of alcohol, which is reflected in shorter times to fall asleep, particularly in adults, rather than the sleep disruption that occurs later in the night."
For the study, Nicholas and his colleagues recruited 24 participants (12 female, 12 male), healthy 18- to 21-year-old social drinkers who had consumed less than seven standard drinks per week during the previous 30 days. Each participant underwent two conditions: pre-sleep alcohol as well as a placebo, followed by standard polysomnography with comprehensive EEG recordings. Results showed that alcohol increased SWS delta power during NREM. However, there was a simultaneous increase in frontal alpha power.
"For individuals researching sleep in the field of alcohol studies, our findings indicate that care needs to be taken when interpreting increases in 'visually scored' SWS associated with alcohol consumption. Increases in SWS, which traditionally would be interpreted as a good thing, can be associated with more subtle changes indicating disrupted sleep, such as the increases we observed in alpha activity, which are revealed when more detailed micro-structural components of the sleep electroencephalogram are assessed," Nicholas said. Nicholas explained that the increase in frontal alpha power that occurs as a result of pre-sleep drinking likely reflects a disruption of the normal properties of NREM slow wave sleep.
"Similar increases in alpha-delta activity, which are associated with poor or un-refreshing sleep and daytime function, have been observed in individuals with chronic pain conditions," he said. "Thus, if sleep is being disrupted regularly by pre-sleep alcohol consumption, particularly over long periods of time, this could have significant detrimental effects on daytime well-being and neuro-cognitive function such as learning and memory processes."
Based on the findings, researchers concluded that alcohol is not a sleep aid. "The take-home message here is that alcohol is not actually a particularly good sleep aid even though it may seem like it helps you get to sleep quicker. In fact, the quality of the sleep you get is significantly altered and disrupted," Nicholas said.
New research by Idaho State University's Maria Wong on the relationship between poor and insufficient sleep for adolescents and them developing alcohol and drug problems has again gained international publicity. Her latest published research notes that sleep difficulties and insufficient sleep are common among US youth; new research has found that sleep difficulties can predict specific substance-related problems; and problems include binge drinking, driving under the influence of alcohol and risky sexual behaviour.
Sleep difficulties and insufficient sleep are common among youth in the US, according to Wong. Prior research has shown that poor sleep can predict alcohol-related problems and illicit drug use among adolescents and young adults in high-risk samples. A new study has 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 in a nationally representative sample.
"National polls indicate that 27% of school-aged children and 45% of adolescents do not sleep enough," said Wong, professor and director of experimental training in the ISU Department of Psychology. "Other studies have shown that about one in 10 adolescents have trouble falling asleep or staying asleep almost every day, or every day, in the previous 12 months."
"This paper is important in that it advances our understanding of the relation of sleep to substance use problems to include not only problems sleeping, that is, trouble falling asleep and/or staying asleep, but also insufficient sleep, addressed here as hours of sleep," added Tim Roehrs, director of research at the Sleep Disorders and Research Centre at the Henry Ford Hospital, and one of the first researchers to identify sleep insufficiency as a clinical issue in the 1990s.
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 Wong. 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. Over-tiredness in childhood has predicted lower response inhibition in adolescence, which in turn predicted number of illicit drugs used in young adulthood. Over-tiredness 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 and her co-authors analysed data collected via interviews and questionnaires from 6,504 adolescents (52% girls, 48% boys) participating in the National Longitudinal Study of Adolescent Health. 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, getting drunk on alcohol, driving under the influence of alcohol, getting into sexual situations one later regretted due to drinking, and using illicit drugs and drug-related problems at the second wave," said Wong. "Substance-related problems such as binge drinking, driving under the influence of alcohol, and risky sexual behavior are more important than others due to their association with reckless driving, automobile accidents, physical injuries and even death, as well as risk for sexually transmitted disease and unplanned pregnancy."
Previous studies on adolescents were mostly drawn from high risk samples, Wong said. 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.
Both Wong and Roehrs believe that parents can play a significant role regarding their adolescents' sleep habits. Parents could monitor adolescents' sleep, help their children develop good hygiene, and talk to them about the importance of sleep. Getting professional help is necessary if sleep problems persist.
"And remember," added Roehrs, "when you monitor the sleep health of your adolescent, there can be two different issues: sleep difficulty and sleep insufficiency."
[link url="http://www.universityherald.com/articles/14969/20150119/drinking-alcohol-before-bedtime-may-disrupt-sleep.htm"]Full University Herald report[/link]
[link url="http://onlinelibrary.wiley.com/doi/10.1111/acer.12621/abstract;jsessionid=20902CE21960CF9E20955D45314B1653.f03t01"]Alcoholism: Clinical & Experimental Research abstract[/link]
[link url="http://www.isu.edu/headlines/?p=7196"]Idaho State University release[/link]
[link url="http://onlinelibrary.wiley.com/doi/10.1111/acer.12618/abstract;jsessionid=6120F7FF201B6E4FD89D5D80DE8675C6.f02t01"]Alcoholism: Clinical & Experimental Research abstract[/link]