Sleep quality among community-dwelling elderly people and its
demographic, mental, and physical correlates
Chia-Yi Wua, Tung-Ping Sub, Chin-Lung Fangc, Mei Yeh Changa,*
aDepartment of Nursing, College of Medicine, National Taiwan University, Taipei, Taiwan, ROC
bDepartment of Psychiatry, Taipei Veterans General Hospital, Taipei, Taiwan, ROC
cDepartment of Physical Education, National Taiwan Normal University, Taipei, Taiwan, ROC
Received January 14, 2011; accepted October 24, 2011
Background: Sleep quality is an important predictor of well being in the elderly. However, the effects of depression and physical activity on sleep
quality among elderly are less clear.
Methods: One hundred older individuals who met the inclusion criteria were randomly sampled from a Taipei district elderly residential list.
Door-to-door interviews were conducted. Sleep quality (the outcome variable), physical activity and depression symptoms were measured by the
Pittsburgh Sleep Quality Index (PSQI), Physical Activity Scale for the Elderly (PASE), and Taiwanese Depression Questionnaire (TDQ),
respectively. Logistic regression was performed to examine the relationship between the above major variables.
Results: A half of the elderly had short sleep onset (<15 minutes) but reported poor sleep quality (PSQI > 5). Twenty-two percent of
community-dwelling elders used psychoactive medication for sleep. The prevalence of depressive disorders (TDQ ? 19) was 7%. Although both
physical activity and depression were significantly associated with sleep quality in the univariate analysis, only depression remained significant
after adjusting for age, gender, education, marital status, and chronic illness confounders in logistic regression (OR ¼ 1.31, 95% confidence
interval ¼ 1.12e1.52).
Conclusion: Elderly depression symptoms was the only factor significantly associating with poor sleep quality after adjustment. Higher level of
physical activity was associated with better sleep quality in univariate analysis but not in multivariate analysis, which considered the factor of
elderly depression symptoms in the elderly. The role of physical activity in late life potentially influence sleep quality but may have less
significance compared with depression. Therefore, we suggest the need for more future research to investigate the relationship between elderly
people’s sleep and physical activity.
Copyright ? 2012 Elsevier Taiwan LLC and the Chinese Medical Association. All rights reserved.
Keywords: community-dwelling elderly; depression; physical activity; sleep quality
Sleep problems in old age are prevalent and have been
known to be associated with physical and psychological
factors.1e3Depression and hypnotics use were, in particular,
suggested as strong correlates with poor sleep.4,5Conversely,
various alterations of sleep architecture (e.g., decreased deep
sleep, impaired sleep continuity, and duration) can be identi-
fied in patients with depression.6The relationship between
depression and sleep disturbance has been hypothesized to be
bidirectional, with depression increasing the risk of poor sleep
and poor sleep predicting depression.3,6,7While late-life
depression in the community was prevalent, ranging from
8.8%e15.3%,4,8severe depressive disorder was found in less
than 3% of these people.9Different manifestations of late-life
depression that might be distinctive from major depression4
are likely to be one of the explanations causing variations
in prevalence. Alhough no known relationship has been
* Corresponding author. Dr. Mei Yeh Chang, Department of Nursing,
College of Medicine, National Taiwan University, 1, Section 1, Jen-Ai Road,
Taipei 100, Taiwan, ROC.
E-mail address: firstname.lastname@example.org (M. Yeh Chang).
Available online at www.sciencedirect.com
Journal of the Chinese Medical Association 75 (2012) 75e80
1726-4901/$ - see front matter Copyright ? 2012 Elsevier Taiwan LLC and the Chinese Medical Association. All rights reserved.
confirmed, the effects of other personal and physical health-
related factors should be studied further to broaden health
promotion strategies for sleep and depression.10
Given that the elderly are vulnerable to mental illness and
sleep problems, physical health conditions and body activity
level further confound the above interactions. The mechanism
between them has been unclear, but physical activity has been
empirically regarded as a facilitator for mental health and
sleep.10In observational studies, physical health and sleep
quality were demonstrated to be significantly linked to each
other.11,12Specifically, exercise or regular physical activity
was found to be protective for people with fatigue syndrome,
and they may also promote sleep and quality of life in patients
with cancer.13,14While the majority of studies supported their
relationship,15e17some were against the effect of exercise on
sleep quality.18A possible explanation for the neutral effect of
exercise is that researchers assessed whether participants had
exercised over a certain intensity and frequency (e.g., more
than three times a week, more than 30 minutes each time),
which may not be sensitive enough to detect minor difference
of levels of physical activity among the two groups of people
with better or worse sleep. Therefore, the definition of phys-
ical activity should be identified when making comparison
Elderly physical activity is different from that of the young
population and requires a short and categorized enquiry format
based on different activity levels to get reliable responses.19
The aspects of physical activity can be defined as including
light/moderate/heavy intensity activities, household chores
and activities,20occupational activities, and sports.19,21Older
people were found to have lessened association between
emotion, physical activity, and sleep compared with younger
counterparts.10However, previous studies have not investi-
gated the relationship between depression, physical activity,
and sleep quality among community-dwelling elderly people.
It was therefore the aim of the study to examine these factors
and their impact on sleep quality among the elderly pop-
ulation. In considering both the influences of depression and
physical activity, it was hypothesized that they would be
significantly correlated with sleep quality, adjusting for
potential confounding factors.
2.1. Study setting
The study was a cross-sectional survey of older residents
more than 65 years of age in Da-An District in Taipei City,
Taiwan, where there were approximately 310,000 residents22
(district elderly population was about 21,700). The district is
situated in the south central area of Taipei and known for its
accumulated educational institutes, recreational places, and
high-level of socioeconomic populations, particularly among
the elderly. The researchers acquired approval from the
Research Review Committee of the Graduate Institute of
Department of Nursing, National Taiwan University, Taipei,
and received a residential list from the District Health Service
Center (DHSC). In order to get a district representative study
group, simple random sampling was employed. According to
Polit and Hungler,23sample size was estimated as 126 when
the significance level (a) was set at 0.05, power was set to be
0.80, and the effect size as 0.25. Given a response rate of
around 70%, the authors needed to obtain a sample of 180
individuals. Thus, simple random sampling was performed
based on the district elderly list provided by the DHSC, with
the elderly being numbered to achieve the study sample of
180. Door-to door interviews resulted in a total of 100 older
people who agreed to participate with written informed
consent (response rate, 55.6%). Those conforming to the
following inclusions criteria were included in the study: (a)
age of 65 years and older, (b) no observable physical
impairment, (c) spoke Mandarin or Taiwanese, and (d) no
recognizable cognitive impairment as measured by the Short
and Portable Mental State Questionnaire (SPMSQ) in order to
get reliable responses.24All of the participants were instructed
with the study by telephone before home visits. Face-to-face
interviews with a structured questionnaire were accom-
plished by one of the authors to ensure consistency during the
year of 2001.
The researchers collected data of demographic features (i.e.,
age, sex, education status, and marital status) and self-reported
chronic illness of all physical systems based on a physician’s
diagnosis. Self-rated health status was regarded as covariate in
this study, which was defined as a personal perception of one’s
poor; 5 as very good). The scales used to measure sleep quality,
physical activity, and depression symptoms were the Pittsburgh
Sleep Quality Index (PSQI), the Physical Activity Scale for the
Elderly (PASE), and Taiwanese Depression Questionnaire
(TDQ)-Chinese versions, respectively. These measures were
valid and showed good test-retest reliability in other stud-
ies25e27and the current one (Pearson’s correlations between
test-retest results were 0.79, 0.89, and 0.91).
The scale assesses a person’s reported sleep status in the
past month. It evaluates personal attribution of poor sleep,
including nine reasons for sleep disturbance (difficulty falling
asleep within 30 minutes, midnight awakening, toileting,
difficulty breathing, coughing, too cold/hot, pain, nightmare,
snoring, and others) and abnormal sleep that caused difficul-
ties of functional performances (difficulty staying awake for
driving, eating or daytime social activities, difficulty staying
energetic to do things well, prescribed or over-the-counter
psychoactive medication used for sleep). The more frequently
the symptoms appeared, the higher the scores and the worse
the sleep quality. For example, the researcher asked a person,
“How many days in a week over the past month did you suffer
from poor sleep due to difficulty falling asleep within 30
minutes?” The ratings 0e3 indicate never, once a week, twice
a week, and more than three times a week, respectively, and
76 C.-Y. Wu et al. / Journal of the Chinese Medical Association 75 (2012) 75e80
the range of total score is between 0e21. The scale has been
found to be a valid and reliable scale, with retest reliability of
0.84 in a group of Taiwanese elders living in an institution.18
A cut-off point of 5/6 was used in this study, with higher
scores indicating worse sleep quality.28
The TDQ is a DSM-III-R derived scale that includes 18
depression symptoms that screen the tendency for elderly
depression in the community. The researchers evaluated the
affection, behavior, cognitive, and drive change during the past
week, which were likely to be clinically significant for
a diagnosis of major depression. All items were summed to get
a total score of 0e54, with higher score of 0e3 in each item
indicating worse mental health status (no or seldom, some-
times, often, most of the time, or always). A cut-off point at
18/19 resulted in 89% sensitivity and 92% specificity, and was
suggested as a valid and reliable screening tool for late-life
depression in the community.26
Considering different intensity, frequency, duration, and
types of physical activities among the elderly, a structured
questionnaire that is inclusive of specific activity types for the
elderly is suitable for epidemiologic surveys.19In this study,
PASE was used to measure the participants’ general activity
level. It was originally designed to measure the quantity and
quality of physical activity in the past week among
community-dwelling elderly people in large epidemiologic
studies.19In this study, the scale was slightly modified from
the Hong Kong version provided by the original inventor. The
utilization of the permitted Chinese version used in Taiwan
was developed by the authors due to linguistic difference
between both spoken and written language used in Taiwan and
Hong Kong. The assessment included the duration of physical
activity per day (less than 1 hour, 1 w 2 hours, 3 w 4 hours,
more than 4 hours) and frequency of each level of physical
activity per week (never, 1 w 2 days, 3 w 4 days, and 5w 7
days) inclusive of different intensity of activities from low,
medium, and strenuous levels to muscle endurance activities
as well as house chores. Calculation of the total score was first
based on an item-by-item recoding procedure. The pairwise
items of weekly frequency and duration of activity were then
multiplied and divided by 7 to get an average daily activity
level. All sets of scores were then summed after multiplying
each score by a constant to weigh different components of
physical activity. Three-week retest reliability was performed
on 37 participants in a subgroup of elderly people from
a public elderly residential house and was found to be highly
correlated (r ¼ 0.89, p < 0.001) in the pilot stage of this study.
The results showed that the PASE-Chinese version is a highly
reliable and valid study tool to be used in the community
setting for the elderly. Moreover, the authors used a ‘6-minute
walk test’29to validate the scale and which scores (in minutes)
showed significant association with PASE scores (r ¼ 0.38,
p < 0.01). Apart from construct validity, the authors revised
the activity classification table according to two researchers
with professional backgrounds in physical education. Consid-
ering the cultural differences and adequacy of applying the
survey to Taiwanese elderly, items that did not exist or were
not suitably classified in the society of Taiwan were revised
according to the following principle:
1. Items removed from the original scale due to low preva-
lence in Taiwan: Arrow technique, rowing boats, cricket,
horse riding, ice skating, darting, football, etc.
2. Items modified due to cultural difference: “yoga” and
“gymnastics” were recategorized from the original category
into low- and medium-intensity activity, respectively.
3. Items added into the physical activity list: Going window-
shopping was added into the category of “strolling”
because it is a common physical activity among Taiwanese
Moreover, the following activities were included in the
low-/medium-/heavy-intensity physical activity categories in
the list: Singing/hiking or fast walking, swinging the hula
hoop, and various Qigong exercises/climbing stairs.
2.3. Data analysis
The authors first tested the feature of normal distribution
of the main continuous variables, including sleep quality,
depression, and physical activity as measured by PSQI, TDQ,
and PASE, respectively. Data were ensured as having normal
distribution before being adopted into further analytical anal-
ysis.30The variables of sleep quality in continuous and cate-
gorical forms were utilized in univariate and multivariate
analysis, respectively. Univariate analysis by independent t-test
for binary variables and one-way analysis of variance for vari-
ables of multiple categories were performed. Depression and
based on the value of diagnostic cut-off point and mean score of
the study participants, respectively, for univariate analysis.
Significance level was set at p< 0.05. Factors that were signifi-
cantly associated with elderly sleep quality in the univariate
analysis were considered to be potential confounding factors.
The rationale for the selection of adjusting factors in the multi-
variate model was based on the parsimony principle and statis-
tical results. Further, multivariate analysis by logistic regression
with the “enter” method selected was executed to examine
significant factors related to late-life sleep. In the logistic
regression model, sleep quality was entered as the dependent
variable, while physical activity and depression were the major
exposures of interest. Moreover, the odds ratio and 95% confi-
dence interval were calculated to evaluate the impact of each
consideredfactor selectedinthemodel. SPSSfor Windows14.0
(Chicago, Illinois) was used to perform all of the analyses.
The study sample was comprised of 100 community-
dwelling elderly people, and 55% of them were women. The
77C.-Y. Wu et al. / Journal of the Chinese Medical Association 75 (2012) 75e80
mean age of the sample was 74.7 ? 5.3 years. About one-half
the patients (49%) reported poor sleep quality (PSQI > 5).
Mean PSQI score was 6.3 ?4.4. Forty-two percent of the
sample had total sleep time of over 7 hours, while 9% reported
less than 5 hours. In terms of sleep onset, 47% fell asleep
within 15 minutes; 28% of them fell asleep after over 30
minutes. The three major reasons for sleep disturbances of the
participants who suffered sleep disturbance in a week (at least
three times) were visits to the toilet (78%), loud snoring (either
partner or her/himself) (19%), and nightmare (19%). More-
over, 22% of the community-dwelling elders used psychoac-
tive medication at least once a week to help their sleep.
Women had significantly worse sleep compared with men
(Table 1). Age and education did not significantly correlate
with poor sleep. Better self-rated health status was associated
with better sleep quality. Those participants who evaluated
their own health as good or very good slept much better than
those reported to have poor health status. As for the influence
of chronic illness conditions, cardiovascular disease, hyper-
tension, musculoskeletal disease, endocrine, and metabolic
disease were all found to be correlated with sleep quality, with
those diagnosed with endocrine-metabolic disease having the
worse quality of sleep.
Overall, 40% of the participants did not have exercise habit,
and 63% had lower physical activity than the average score as
a whole (Table 1). The average score of PASE for the total
sample was 60.1 ?41.4, with men and women scored
64.6 ? 39.9 and 56.5 ? 42.6, respectively (p ¼ 0.24). It was
consistent that elderly people with exercise habit or higher
level of physical activity had better sleep quality. Those with
exercise habit had lower scores on PSQI (5.7 ?3.9) than those
without (7.3 ? 5.0) (p ¼ 0.08).
The prevalence of potential depressive disorders (TDQ
score ? 19) was 7% among the community-dwelling elderly
(Table 1). Mean score for TDQ for the sample was 5.1 ? 7.0.
Association between depression (using the standard cutoff
18/19) and sleep quality was significant. Moreover, correlation
between main variables of sleep quality, depression scores, and
physical activity scores indicated that they were all signifi-
cantly correlated with each other (Table 2). In summary,
factors that were found to be significantly associated with
sleep quality in univariate analysis included female sex,
self-rated health status, chronic illnesses, level of physical
activity, and depression symptoms. Findings from the logistic
regression (Table 3) showed that elderly depression symptoms
was the only factor associating with sleep quality after
adjusting for age, sex, education, marital status, and chronic
illnesses (odds ratio ¼ 1.31, 95% confidence interval ¼
In a secondary analysis of the relationship between
psychoactive medication use and the three main variables of
this study, medication use was significantly associated with
worse sleep quality (10.6 ? 4.5 vs 5.1 ? 3.6, p < 0.001) and
more depression symptoms (7.2? 2.8 vs 3.7 ? 5.9, p < 0.001)
but not with the level of physical activity.
Furthermore, in considering potential risk of multi-
collinearity in the regression model, the authors selected
variables based on findings of univariate analysis and checked
the correlation matrix between them (Table 2). A test of
collinearity was also performed and showed that it was less of
a concern (variance inflation factors value ¼ 1.8; toler-
ance ¼ 0.8).31The above test indicated that the results of this
study were relatively genuine.
Univariate analysis of sleep quality score with related factors (n¼100).
Variablesn Mean SDp value
Age groups65w 69
College and above
Very poor (1)
Very good (5)
Physical activity Higher than average
Lower than average
aScheffe test results indicated that between-group differences of sleep
quality in self-rated health were poor > good, poor > very good.
Correlationamatrix of age, self-rated health and main continuous variables of
Physical activity ?0.249 * ?0.271 ** 0.192
-0.414 *** 1.000
?0.419 *** ?0.234 * 1.000
* p<0.05; ** p<0.01; *** p<0.001.
aPearson’s correlation was performed in these statistics.
78C.-Y. Wu et al. / Journal of the Chinese Medical Association 75 (2012) 75e80
4.1. Major findings
The study recruited a sample of elderly residents of Da-An
District in Taipei. One hundred community-dwelling elders
were interviewed via home visits, and 49% of them reported
poor sleep quality (PSQI score > 5). It was found that 22% of
the study participants used psychoactive medication to help
them sleep; 7% reported having significant depression symp-
toms (TDQ ? 19). Higher level of physical activity was
associated with better sleep quality when independently
considering physical influence on sleep; however, the above
correlation was confounded by depression, which was signif-
icantly associated with poor sleep quality after adjusting for
age, sex, education, marital status, and chronic illnesses. In
summary, depression may have more influence on elderly
sleep when a person suffered from both mental and physical
4.2. Geriatric depression and its influence on sleep
This study highlights the need for early identification and
intervention of depression symptoms in geriatric population
with sleep problems. The 1-week prevalence of depression
was 7% among the community-dwelling elderly people in this
study, which was comparable with some studies in Taiwan
(8.8%e9.8%)4,32but lower than others (1-month prevalence of
neurotic depression: 15.3%).8Reasons for lower prevalence
may be related to different diagnostic criteria for the definition
of geriatric depression (e.g., neurotic depression or major
depression) and various screening tools selected in community
surveys. Therefore, one should be cautious when making
comparison between studies. Furthermore, depression was
identified as one of the main factors contributing to sleep
problems.3,11,32e34In this study, depression was the only
factor when considering related factors to be associated with
sleep quality, making mental health assessment an important
strategy in alleviating sleep problems. Notably, the 22% of
patients reporting psychoactive medication use for sleep in the
past month was consistent with other studies.3,5Previous study
pointed out that such medication use by the elderly might
strongly attenuate the relationship between depression and
Another issue concerned the fidelity of correlation between
depression and sleep quality when using the two screening
scales (TDQ and PSQI, respectively) with overlapping
symptom measurement, i.e., sleep problems. It should be
noted that the TDQ is an overall assessment of depressive
related symptoms in community-dwelling elders, with sleep
problem being one of the 18 items. The general score over
a cut-off point stands for elevated possibility of clinically
significant depressive disorders. Hence, there is not a single
item that can determine the severity of sleep problems.
Moreover, to validate this correlation, we removed the sleep-
related item in the TDQ and found the significance remained
(r ¼ 0.45, p < 0.001). Hence, the finding regarding the rela-
tionship between the two variables should be relatively true
4.3. Elderly physical activity and its correlation with
The results confirmed the effect of elderly physical activity
on sleep, but we should first consider the influence of depres-
sion when elderly people have both physical and mental
problems. It was suggested that depression may have more
influence compared with physical and other demographic
factors. Although plenty of studies supporting the positive
effect of physical activity on sleep,12,15e17the role of depres-
sion cannot be neglected and should be dealt with prioritization
before considering any exercise protocol or physical health
promotion in the elderly.
4.4. Study limitations and implications
The current study has provided evidence on the significance
of late-life depression for sleep among the community-
dwelling elderly. It is among the few studies that concur-
rently considered quantitative physical activity level, sleep
quality, and depression in a community-dwelling elderly
sample. However, there were several limitations. First, gener-
alizability of this study is limited because the sample size was
too small for drawing firmer conclusions. Also, we failed to get
demographic details of nonparticipants from the District
Health Service Center to make comparison with participants.
But the use of face-to-face interview method during field data
collection obviously increased the reliability of the findings.
Secondly, the evaluation of sleep quality and major variables
were self-reported and might have resulted in memory or
information bias, even though the researcher had used
systematic techniques to draw responses. For example, poor
sleep in the TDQ was found in 23% of study patients, while
49% of them reported good sleep quality measured by PSQI ?
5. However, there was only one question in TDQ evaluating
overall sleep quality, while the PSQI has a set of sleep
measurement components that could be more specific. They
served different purposes and should be interpreted based on
the total score. Thirdly, sleep measurement was based on
subjective descriptions rather than objective assessment. There
might be memory gap between certain variables such as total
Logistic regressionaof the factors predicting sleep quality of community-
dwelling elderly people.
Variables Odds ratio95% confidence intervalp value
Self-rated health statusb
aThe model was adjusted for age, sex, education, marital status, and chronic
bContinuous form of these variables was put in the model for analysis.
79C.-Y. Wu et al. / Journal of the Chinese Medical Association 75 (2012) 75e80
sleep time and sleep onset, subsequently influencing the
classification of people with good or bad sleep quality based
on total score of PSQI and the results of this study. Future
studies are recommended to prospectively follow up a cohort
of community-dwelling elders to evaluate elderly depression
symptoms and their effect on the relationship between physical
activity and sleep quality over time.
In conclusion, this study provides evidence that depression
among the elderly has a significant influence on sleep quality
in the community setting. Frontline community healthcare
professionals should raise community awareness regarding
chief complaints and symptoms related to depression and
The authors are grateful to the elderly people who agreed to
participate and the administration who helped provide
community nurses in the District Health Promotion Center in
the Da-An area in Taipei City. Moreover, thanks to Professor
Chun-Chen Juo of the Department of Physical Education in
National Taiwan Normal University for providing his profes-
sional opinions to develop the face validity of the Physical
Activity Scale for the Elderly-Chinese version.
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