Copyright © 2015 The Korean Academy of Family Medicine
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The Effects of Alcohol on Quality of
, Mi-Kyeong Oh
*, Bum-Soon Lee
, Haa-Gyoung Kim
, Won-Joon Lee
, Ji-Ho Lee
, Jun-Tae Lim
Department of Family Medicine, Gangneung Asan Hospital, University of Ulsan, College of Medicine, Gangneung, Korea
Department of Family Medicine, Chungbuk National University Hospital, Cheongju, Korea
Background: Alcohol is traditionally known to have a relaxing effect. However, persons who consume alcohol in
excessive amounts suffer from poor sleep quality and patients with alcohol use disorders commonly report insom-
nia. In this study, we aimed to evaluate the effects of alcohol use on sleep quality.
Methods: A questionnaire-based cross-sectional survey was conducted with 234 men and 159 women who had
visited a general hospital. We used structured questionnaires, including Alcohol Use Disorder Identification Test-
Korean revised version (AUDIT-KR) and the Pittsburgh Sleep Quality Index-Korean version (PSQI-K). We analyzed
the association between scores for all subcategories of the PSQI-K and the AUDIT-KR and then analyzed the corre-
lation between AUDIT-KR and global PSQI-K scores.
Results: The global PSQI-K score for men was positively correlated with the AUDIT-KR score (P= 0.008) after ad-
justing for age, chronic disease, tobacco use, exercise, depression, and anxiety. The AUDIT-KR score was significant-
ly associated with subjective sleep quality (P = 0.005), sleep duration (P = 0.047), and sleep disturbance (P = 0.048); it
was not associated with sleep latency, sleep efficiency, or daytime dysfunction. Sleep disturbances due to snoring
were significantly associated with total AUDIT-KR score (P= 0.008). There was no correlation between the global
PSQI-K and AUDIT-KR scores for women (P = 0.333). However, daytime dysfunction showed a significant associa-
tion with total AUDIT-KR score (P= 0.048).
Conclusion: Men with higher AUDIT-KR scores tended to suffer from poor sleep quality. AUDIT-KR scores showed
significant correlations with subjective sleep quality, sleep duration, and sleep disturbances in men.
Keywords: Alcohol Drinking; Sleep Disorders; Sleep Quality
Received: August 31, 2015, Revised: September 24, 2015, Accepted: September 30, 2015
*Corresponding Author: Mi-Kyeong Oh Tel: +82-33-610-3325, Fax: +82-33-641-8130, E-mail: email@example.com
Korean J Fam Med 2015;36:294-299
Soon-Yeob Park, et al.
Alcohol and Sleep Quality
Sleep is commonly known to facilitate recovery from physical,
mental, and brain fatigue caused by daytime activities. Sleep
allows the human body the rest time required for memory and
learning, preservation of energy, development, and growth.
Recently, several studies on sleep have reported that poor qual-
ity sleep not only leads to increased stress, fatigue, and mood
but also raises risks of obesity, metabolic syndrome,
and cardiovascular disease.
Conversely, many diseases also
affect sleep quality. Depression, anxiety, musculoskeletal dis-
orders, obesity, restless leg syndrome, and other chronic dis-
eases are all known to cause sleep disorders.
Moderate alcohol consumption is known to decrease the
risk of mortality,
while excessive drinking can increase the
onset of various diseases and lead to increased risk of mortali-
Excessive drinking also cause a range of problems with
the nervous system; such problems include memory disorders,
movement disorders, peripheral neuropathy, and reduced learn-
As of 2012, the rate of high-risk drinking (average
alcohol consumption of 7+ drinks on 2+ days per week) among
Korean adults males is 21.8%. The high-risk drinking rate ex-
ceeds 25% for those aged 30–59, indicating that a significant
part of the population is exposed to drinking related dangers.
Among women, on the other hand, the high-risk drinking rate
has been reported at 6.0%.
Alcohol consumption also affects sleep quality in various
ways. A number of studies have shown that drinking momen-
tarily increases sleepiness, but later causes frequent nighttime
and early morning awakenings.
Individuals with alcohol use
disorders frequently consume alcohol before sleep in an effort
to improve their sleep. Many moderate alcohol users also drink
before sleep if they suffer from insomnia. On the contrary, oth-
er studies have shown no correlation between drinking pat-
terns and sleep quality.
While it is believed that drinking
patterns are significantly related to sleep patterns, no empirical
correlation has been confirmed to date and studies on the cor-
relation between drinking patterns and sleep quality of Kore-
ans are virtually non-existent.
Therefore, we conducted this study to examine the effects of
alcohol consumption on sleep quality and to provide recom-
mendations for improving sleep quality.
This study was conducted on patients, and their guardians,
who visited Gangneung Asan Hospital in Gangneung, Korea
from January 2014 to July 2014. Among 560 adults who volun-
tarily completed the informed consent process, subjects diag-
nosed with conditions known to affect sleep, including life-thre-
atening critical diseases, depression, anxiety, restless leg syn-
drome, and sleep apnea were excluded. Thus, we selected 234
men and 159 wo men who sincerely answered study question-
naires. This study was conducted after being reviewed and ap-
proved by the hospital’s institutional review board (GNAH IRB
2. Survey Methods
1) Structured questionnaire
In order to assess basic subject characteristics, a questionnaire
was administered asking about a subject’s age, gender, and med-
ical history (e.g., hypertension, diabetes, dyslipidemia, chronic
musculoskeletal disease, etc.). In order to identify smoking pat-
terns, subjects were categorized as current smokers, former
smokers, or non-smokers. Subjects were also asked about their
exercise habits, including total number and duration of exer-
cise sessions per week. This data was used to categorize sub-
jects into one of three exercise levels: those exercising less than
once per week, those exercising 1–2 times per week, and those
exercising 3 times or more per week.
Although persons with a history of depression or anxiety
were excluded from the study, we used a depression and anxi-
ety screening tool, which has been standardized in Korea; this
tool was used in order to correct for the role of depression or
anxiety that are known to affect sleep quality. More specifically,
we used the ‘two-question depression test’ and those who an-
swered yes to one or both of the questions were assumed to be
experiencing some level of depression.
We also asked sub-
jects four questions covering primary symptoms of anxiety,
adapted from the Korean-translated Goldberg Anxiety Scale
(GAS). Those who answered yes to two or more of the four ques-
tions were assumed to be experiencing some level of anxiety.
2) Alcohol drinking state assessment questionnaire
In order to investigate alcohol consumption rates, we used the
Alcohol Use Disorder Identification Test-Korean revised ver-
sion (AUDIT-KR), a tested and validated Korean version of the
AUDIT that is widely used for assessment of alcohol use disor-
ders and hazardous drinking.
The AUDIT-KR consists of 10
questions, with each question rated on a 4-point scale. The high-
er the respondent’s alcohol dependency, the higher the total
score. The maximum possible score is 40 points. The cutoff val-
ue for alcohol use disorders is 10 points for men and 8 points
3) Sleep quality assessment questionnaire
In order to evaluate subjects’ sleep quality, we used the Pitts-
burgh Sleep Quality Index-Korean version (PSQI-K), a tested
and validated Korean-language version of the Pittsburgh Sleep
Quality Index (PSQI), which has been widely used as a sleep
quality assessment tool since its translation in 2012.
Soon-Yeob Park, et al.
Alcohol and Sleep Quality296
vestigated the scores of the 7 components of the PSQI-K that
affect sleep quality: subjective sleep quality, sleep duration,
sleep latency, habitual sleep efficiency, sleep disturbance, use
of sleep medication, and daytime dysfunction. The global score
of the PSQI-K is the sum of all component scores. The mini-
mum possible score is 0, indicating ideal sleep quality, and the
maximum possible score is 21, indicating poor sleep quality.
Subjects with total scores of 5 and below were defined as ‘good
sleepers,’ and those with total scores of 6 and above were de-
fined as ‘poor sleepers.’ The 7 component scores are rated on a
3-point ascending scale, with 0 points indicating ideal sleep
quality and 3 points indicating poor sleep quality. Each com-
ponent score of 0–1 points was determined as having good ef-
fects on sleep quality, while scores of 2–3 points were determin-
ed as having bad effects on sleep quality.
3. Statistical Analysis
In this study, we used PASW SPSS Statistics ver. 18.0 (SPSS Inc.,
Chicago, IL, USA) for statistical analyses with significance level
set at less than 0.05 for all statistical operations. We performed
chi-square tests and independent sample t-tests to assess gen-
der differences in initial reports of underlying disease, smoking
status, exercise frequency, depressive symptoms, and anxiety
symptoms. We used the Wilcoxon two-sample test to assess
gender differences in AUDIT-KR scores. To investigate the rela-
tionship between global or component scores of the PSQI-K
and AUDIT-KR scores, we performed the Mann-Whitney test.
In order to analyze the correlation between AUDIT-KR scores
and PSQI-K scores, we performed a multiple linear regression
analysis adjusting for age, chronic disease, current smoking
status, regular exercise, two-question depression test scores,
and GAS scores. Any subjects diagnosed with hypertension, di-
abetes, ischemic heart disease, stroke, or chronic musculoskel-
etal diseases and undergoing treatment at the hospital for any
of these conditions were defined as having chronic disease, for
the purposes of this study. Subjects who reported that they ex-
ercised 3 times or more per week were defined as regular exer-
1. Baseline Characteristics of Subjects
The average age of the subjects was 51.1± 12.0 years for men
and 48.6 ± 10.0 years for women. The number of subjects cate-
gorized as having chronic disease was significantly greater among
men as compared to women (P = 0.001). As for smoking status,
the number of current smoker and former smokers were sig-
nificantly greater among men than women (P< 0.001). Report-
ed frequency of weekly exercise was also significantly greater
among men than women in this study (P= 0.004).
Total AUDIT-KR scores were significantly higher among men
than women (P< 0.001) and the number of subjects categorized
as having an alcohol use disorder was also significantly greater
among males than females (P<0.001). According to results of
the depression and anxiety screening tests, there were no sig-
nificant gender differences between subjects with symptoms of
depression and those with symptoms of anxiety. While global
PSQI-K score was significantly higher among men than women
(P = 0.033), when subjects were categorized by sleep quality
(good sleepers and poor sleepers) the ratio of poor sleepers be-
came non-significant (P= 0.114) (Table 1).
2. Relationship between Each Component of Sleep Quality
and Alcohol Use Disorder Identification Test-Korean
Revised Version Score
When our subjects were categorized by sleep quality, based
upon their total PSQI-K scores, there were no significant differ-
ences between the two groups and AUDIT-KR scores for either
men or women. Examination of the correlation between each
PSQI-K component score and AUDIT-KR score among men,
revealed that the group with poor subjective sleep quality show-
ed significantly higher AUDIT-KR scores than the group with
good subjective sleep quality (P = 0.005). Additionally, subjects
with short sleep duration ( < 6 hours of sleep per night on aver-
Table 1. Baseline characteristic of study subjects
Variable Men (n = 234) Women (n=159) P-value*
Age (y) 51.1
Ischemic heart disease
1–2 times a week
At least 3 times a week
Depressive mood 64 (27.4) 49 (30.8) 0.456
Anxious mood 33 (14.1) 23 (14.5) 0.920
AUDIT-KR 9 [3,16]
Alcohol use disorder
Pittsburgh Sleep Quality
Good sleeper (score ≤ 5) (%)
Poor sleeper (score > 5) (%)
5 [3, 7]
4 [3, 6]
Values are presented as mean
standard deviation or number (%).
AUDIT-KR, Alcohol Use Disorder Identification Test-Korean Revised.
*By independent sample t-test or chi-square test.
Values are presented as median
[25 percentile, 75 percentile].
By Wilcoxon two-sample test.
Alcohol use disorder is
indicated by an of AUDIT-KR cutoff value greater than 10 points in men and 8 points
Soon-Yeob Park, et al.
Alcohol and Sleep Quality
age) showed significantly higher AUDIT-KR scores than those
with longer sleep duration (P= 0.047). Among men, those with
more sleep disturbances showed significantly higher AUDIT-
KR scores than those with fewer sleep disturbances (P= 0.048).
No significant differences in the correlation between AUDIT-
KR scores were noted for sleep latency, sleep efficiency, and
daytime dysfunction components. Although there was no sta-
tistical significance among individual sleep efficiency items,
the group with lower efficiency tended to have higher AUDIT-
KR scores as compared to the group with higher efficiency (P =
0.09). Subjects waking up from sleep, due to snoring, at least
once per week showed significantly higher AUDIT-KR scores
than other subjects (P= 0.008) (Table 2).
Among women, those with more daytime dysfunction showed
significantly higher AUDIT-KR scores than those with lower
daytime dysfunction (P= 0.048), but the differences in AUDIT-
KR scores were insignificant in relation to other components
3. Multiple Linear Regression Analysis between Alcohol Use
Disorder Identification Test-Korean Revised Version
Scores and Sleep Quality Scores
When a linear regression analysis was performed on the corre-
lation between male AUDIT-KR and PSQI-K scores, a signifi-
cant positive correlation was found when the factors affecting
sleep were not corrected (P= 0.001). A significant correlation
was found, even after correcting for age, chronic disease, cur-
rent smoking status, regular exercise, depression symptoms,
and anxiety symptoms (P = 0.008). Depression symptoms and
anxiety symptoms were also positively correlated with PSQI-K
Table 2. Relationship between component score of PSQI-K and AUDIT-KR
Component score of PSQI-K
No. AUDIT-KR P-value* No. AUDIT-KR P-value*
Total PSQI-K score
Good sleeper (total score ≤ 5) 136 9.21
7.62 0.105 105 2.45
Poor sleeper (total score > 5) 98 11.53
9.42 54 3.74
Subjective sleep quality
Good 162 9.04
7.81 0.005 125 2.78
Poor 72 12.74
9.29 34 3.29
≤ 30 min 179 9.99
8.21 0.77 116 2.98
> 30 min 55 10.78
9.36 43 2.63
≥ 6 h 207 9.67
8.04 0.047 145 2.81
< 6 h 27 14.07
10.71 14 3.64
≥ 75% 207 9.74
8.11 0.094 148 2.84
< 75% 27 13.56
10.48 11 3.45
No 197 9.52
7.84 0.048 136 2.74
Yes 37 13.68
10.76 23 3.74
No 169 9.87
8.21 0.445 122 2.25
Yes 65 10.98
9.16 37 4.97
< 1 time/wk 167 9.20
8.15 0.008 141 2.87
≥ 1 time/wk 67 12.55
8.89 18 2.83
Values are presented as mean
PSQI-K, Pittsburgh Sleep Quality Index-Korean version; AUDIT-KR, Alcohol Use Disorder Identification Test-Korean Revised version.
*By Mann-Whitney test.
Hours asleep/hours in bed × 100.
Nighttime awakenings due to snoring.
Table 3. Multiple linear regression analysis of sleep quality by global Pittsburgh
Sleep Quality Index-Korean version score
AUDIT-KR 0.215 0.001 0.110 0.166
AUDIT-KR 0.222 0.001 0.071 0.411
Age 0.003 0.969 -0.150 0.142
Chronic disease -0.049 0.482 0.153 0.112
Current smoker -0.004 0.955
-0.122 0.062 -0.114 0.154
AUDIT-KR 0.171 0.008 0.014 0.861
Age -0.026 0.707 -0.104 0.264
Chronic disease -0.028 0.676 0.096 0.271
Current smoker 0.010 0.871
-0.088 0.181 -0.167 0.083
Depressive mood 0.175 0.008 0.258 0.001
Anxious mood 0.175 0.009 0.323 < 0.001
PSQI-K, Pittsburgh Sleep Quality Index-Korean version; AUDIT-KR, Alcohol Use Disorder
Identification Test-Korean revised version.
*Standard regression coefficient.
3 or more exercise sessions per week.
Soon-Yeob Park, et al.
Alcohol and Sleep Quality298
scores (P= 0.008 and P = 0.009, respectively) (Table 3).
Among women, no significant correlation was found between
AUDIT-KR and PSQI-K scores. However, depression symptoms
and anxiety symptoms were found to be significantly and posi-
tively correlated with PSQI-K score (P= 0.001 and P < 0.001, re-
spectively) (Table 3).
In the present study, which focused on the effects of alcohol
consumption on sleep quality among adults aged 20 years and
older, we found that AUDIT-KR and PSQI-K scores were signifi-
cantly correlated among male subjects. In particular, we learned
that alcohol consumption patterns are related to subjective sleep
quality, sleep duration, and sleep continuation. In contrast, sleep
latency was not correlated with alcohol consumption level. In
other words, it appears that men with more alcohol consump-
tion suffer from overall poor sleep quality, experience difficulty
in maintaining sleep rather than falling asleep, suffer from short-
er overall sleep duration, and therefore have worse subjective
sleep quality. Among factors that disturb sleep, it was learned
that snoring, in particular, is linked with alcohol consumption.
Among female subjects, AUDIT-KR and PSQI-K scores were
not correlated. Perhaps this is because the number of female
hazardous drinkers was notably lower than among male sub-
jects and, therefore, the number of subjects with sleep disorder
caused by alcohol might have been too low to yield any statisti-
cally significant result. When examining the correlation between
the subcategories of the PSQI-K and the AUDIT-K among wom-
en, daytime dysfunction was shown to be significantly correlat-
ed with the AUDIT-K; this finding provides a basis for the con-
clusion that alcohol does not affect nighttime sleep duration
among women as greatly as it deteriorates the recovery func-
tions of sleep leading to daytime dysfunction.
Among both men and women, depression symptoms and
anxiety symptoms were significantly correlated with increased
PSQI-K values. In this study, we found that anxiety symptoms
were more strongly correlated with PSQI-K values than depres-
sion symptoms and that women showed greater correlation
between PSQI-K values and anxiety or depression symptoms
as compared to men.
The correlation between alcohol consumption and sleep quali-
ty among men in this study was consistent with results previous-
ly reported by Roehrs and Roth
that alcohol generally disturbs
Chang et al.
and Vinson et al.
found that drin king
does not have significant effects on sleep quality. However, these
two studies did not control for gender and it could be posited that
women act as an effect modifier. In our study, drinking did not
significantly impact sleep quality among women likely because
of generally low rates of alcohol consumption. It follows that
women with problematic alcohol consumption experienced
poorer sleep quality, similar to trends observed among men.
In a laboratory study in which healthy individuals were in-
structed to drink alcohol and then undergo polysomnography,
it was shown that rapid eye movement (REM) sleep was sup-
pressed during the first half of the sleep cycle followed by an
increase during the second half of the sleep cycle.
consumption could induce deep sleep at the beginning of the
sleep cycle, but if sleep continues for a longer duration, overall
sleep quality could deteriorate due to the decreased amount of
slow wave sleep and REM sleep rebound. This is in agreement
with our findings that, among men, drinking decreased overall
sleep duration and increased sleep disturbances.
It has also been reported that alcohol consumption increas-
es sleep apnea
and our study confirmed that number of
nighttime awakenings due to snoring was related to alcohol
consumption. As mentioned above, alcohol prevents entry into
deep sleep and therefore makes a person more susceptible to
sleep disturbances given the same conditions. It has also been
suggested that alcohol relaxes the upper airway muscles, in-
creasing resistance during inhalation, which directly and sig-
nificantly impedes breathing.
A number of studies have reported that depression and anxi-
ety deteriorate overall sleep quality.
Similarly, in this study,
we found a significant correlation between anxiety or depres-
sion symptoms and deterioration in sleep quality among both
men and women. This significant correlation, which remained
after excluding persons already diagnosed with anxiety or de-
pression, reaffirms the importance of effective management of
depression and anxiety for improving sleep quality.
One limitations of this study is that the results may not reflect
the general population because the study only sampled per-
sons who visited a hospital; another limitation is that the num-
ber of female subjects with high alcohol consumption levels
was low and thus yielded limited statistical significance. We
believe that it would be meaningful to conduct further studies
on female subjects to compare the sleep quality between haz-
ardous drinkers or patients with alcohol use disorder and mod-
erate drinkers or persons who do not drink at all. In addition,
further studies are recommended focused on the correlation
between alcohol consumption and sleep apnea or restless leg
syndrome, both of which were found to be significant in the
CONFLICT OF INTEREST
No potential conflict of interest relevant to this article was re-
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