factors associated with quality of life among older adults with chronic disease in taiwan

Original ArticleFactors Associated with Quality of Life Among Older Adults with Hsiao-Mei Chen1,2, Ching-Min Chen3* 1 Institute of Allied Health Sciences, College of Medicine, National C

Original Article

Factors Associated with Quality of Life Among Older Adults with

Hsiao-Mei Chen1,2, Ching-Min Chen3*

1 Institute of Allied Health Sciences, College of Medicine, National Cheng Kung University, 2 Cheng Ching Hospital, Taichung City, 3 Department of Nursing,

National Cheng Kung University, Taiwan

a r t i c l e i n f o

Article history:

Received 1 October 2015

Received in revised form

29 June 2016

Accepted 27 July 2016

Available online xxx

Keywords:

chronic disease,

disability risk,

older adults,

quality of life

s u m m a r y Background: There have been many studies reviewing quality of life (QoL) of older population and found

an inverse association between QoL and chronic diseases However, previous studies have focused only

on that of people with specific diseases In this study, we identified critical quality of life determinants, especially risk for disability, in older adults suffering from chronic diseases

Methods: A cross-sectional, correlational design was used A purposive sample of 115 older patients, diagnosed with co-morbidity was recruited from an outpatient medical center in Southern Taiwan Results: Results of a stepwise multiple regression analysis indicated that the overall regression model explained 49% of the variance in QoL After controlling the sociodemographic factors and health status of older patients, the risk for disabilities in social isolation and depression were negatively correlated with QoL Alzheimer disease-8 (AD-8) had the strongest association with the total QoL score, and it alone explained 27% of the variance

Conclusion: Understanding the importance of determining factors of poor QoL, such as potential cognitive impairment, potential social isolation and depression, inadequate family income, and dimin-ished ability to perform practical and social activities (IADLs) among older adults with chronic diseases is critical for geriatric health care providers Awareness of these factors can assist providers in identifying people at risk and guide new intervention programs to improve care for these invaluable members of our communities

Copyright© 2016, Taiwan Society of Geriatric Emergency & Critical Care Medicine Published by Elsevier Taiwan LLC This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/

licenses/by-nc-nd/4.0/)

1 Introduction

Aging is a global issue1 The older population (aged 65 years and

over) in Taiwan crossed the 7% threshold of an aging society in

1993, and the percentage of aging population has reached 12.50%2

The disability of older adults is closely related to the degree of their

weakness, which is determined by aging, diseases and lack of

ex-ercise3,4 Aging is frequently accompanied by a larger burden of

comorbid conditions and greater illness severity3,5

Aging-associated diseases, such as heart disease, stroke, degenerative arthritis and fractures caused by falls often reduce older adult's capability of activity6,7 Disability can be defined in several ways, including difficulties with activities of daily living (ADL), difficulties with instrumental activities of daily living (IADL), and mobility limitations, impairments, and participation restrictions4,5 Globally, co-morbidity is a common problem and increases with age3,8 The prevalence of chronic diseases among older adults aged 65 and above accounts for approximately 70%, and about one-third of the older adults suffer from co-morbidity8 In addition, chronic diseases and co-morbidity have a considerable degree of influence on the health functions of older adults8,9 With the Charlson Comorbidity Index (CCI), the co-morbidity situation and the disease burden of the chronic disease patients can be understood10 Disability-adjusted life-year (DALY) is a measure of overall disease burden, and mortality and morbidity are combined11 Dementia causes major disability in older adults and is a global public health burden12 The Alzheimer disease 8 is, however, quite sensitive to

* Conflict of interest: The authors declare that there is no conflict of interest.

** Funding: The work was supported by the “Aim for the Top University Plan” of

the National Cheng Kung University and the Ministry of Education, Taiwan, R.O.C

None of the study sponsors or funding sources had a role in the design, conduct,

analysis or reporting of the study.

* Correspondence to: Dr Ching-Min Chen, National Cheng Kung University,

Department of Nursing, 1 University Rd, Tainan, 70101, Taiwan Fax: þ886

62377550.

E-mail address: chingmin@mail.ncku.edu.tw (C.-M Chen).

Contents lists available atScienceDirect

International Journal of Gerontology

jo u rn a l h o m e p a g e :w w w i j g e - o n l i n e c o m

http://dx.doi.org/10.1016/j.ijge.2016.07.002

1873-9598/Copyright © 2016, Taiwan Society of Geriatric Emergency & Critical Care Medicine Published by Elsevier Taiwan LLC This is an open access article under the CC BY-NC-ND license ( http://creativecommons.org/licenses/by-nc-nd/4.0/ ).

International Journal of Gerontology xxx (2016) 1e4

detecting early cognitive changes associated many common

dementing illness13 Older adults who suffer from multiple chronic

diseases and cognitive dysfunction are often rendered physically

impaired14 Therefore, the preventing disability from happening

among older adults has become a government priority in Taiwan

Previous studies on the quality of life (QoL) of older adults have

found an inverse association between QoL and chronic diseases, but

most of the data focused on patients with a specific disease or have

used a wide variety of instruments Thus, studies on the factors

affecting QoL among older adults with multiple chronic diseases

are limited15,16, particularly those on the correlation between risk

for disability and QoL Therefore, the objectives of this study were

(1) to understand QoL of older adults with chronic diseases in

physical and mental health, social relations, and environment

components; (2) to examine the correlations among the

socio-demographic characteristics, health status, risk for disabilities, and

QoL; and (3) to identify impact of disability risk on QoL of older

adults with chronic diseases

2 Materials and methods

2.1 Design and sample

A cross-sectional study design was adopted Participants were

recruited from October to December of 2011 at the outpatient

center of a medical center (Neurology, Cardiology, Metabolism,

Rehabilitation, Family Medicine, etc.) in Southern Taiwan

Purpo-sive sampling was used, and the inclusion criteria included older

adults aged 65 years or over who were (1) physician-diagnosed

with more than one common chronic diseases, (2) able to

communicate in either Mandarin or Taiwanese, (3) willing to

participate in interviews and to complete the questionnaire

inde-pendently or with assistance, and (4) agreed to participate in the

study and signed the letter of consent The exclusion criteria were

severe dementia, disability, visual or hearing impairments, and

inability to communicate Among the participants, 115 were willing

to participate in the interview and complete the questionnaire, 29

declined, and six did not meet the criteria The response rate for this

study was 79.86%

2.2 Data collection process and definitions

Ethical approval for the study was obtained from the

institu-tional review board (IRB) (No: ER-100-359), Nainstitu-tional Cheng Kung

University Hospital After obtaining agreement from the case

hos-pital and outpatient departments, we explained the research

pur-poses to the recruited participants to obtain their agreement and

signed consent forms before beginning data collection

Data on socio-demographic characteristics included age, gender,

marital status, living conditions, religion, level of education, and

economic condition Health status were measured according to

diagnosis, charlson comorbidity index (CCI), Alzheimer disease 8

(AD8), Activities of daily living (ADL) and instrumental activities of

daily living scale (IADL) CCI was developed in 1987 to predict a

relative risk of death within 12 months10 For calculation of CCI, a

standardized weight was assigned in each indicated 19 diagnoses

and added together to provide a total CCI score The scores are

calculated as 0 (no condition occurs), 1, and 2, 3, and 6 points A

higher score indicates a more severe burden of co-morbidity10,17

The AD8 contains 8 items that test for memory, orientation,

judg-ment, and function An AD8 score of2 indicates possible cognitive

impairment and that further diagnosis is required18 The ADL

consists of 10 items The total score ranges from 0 to 10019 The IADL

score of each item ranges from 2 to 4 points, with a total score of 24

points20

The risk for disability scale was adopted from Japan21 The scale comprisesfive subscales, movement (5 items), nutrition (4 items), cognition (5 items), social relations (5 items), and depression (5 items), yielding a total of 24 yes/no questions A score of 1 or above

in each subscale shows disability risk in that domain A higher score indicates that the person is at higher risk of disability22 Quality of Life comprises 28 questions across four domains, physical health, mental health, social relations, and environmental The scoring is based on a 5-point Likert scale The average score of all the ques-tions within the same domain is multiplied by 4 as the score of that domain, which ranges from 4 to 20 The sum of the scores of the four domains represents the overall QoL score23

2.3 Statistical methods Statistical analysis was conducted using the SPSS17.0 Chinese version The frequency, percentage, mean, standard deviation were reported for variable description Independent t test, Pearson cor-relation, one-way analysis of variance (ANOVA), and stepwise multiple regression analysis were used to determine correlations between predicting variables on QoL

3 Results Among the 115 participants, there were more women (62.6%) than men The average age was 70.87 (SD¼ 8.39) Married partic-ipants accounted for 79.1% of the total sample, and a great part of them (53.3%) had a high school (vocational) degree Regarding the income, 69 (62.7%) participants considered it was sufficient, 7 (6.4%) considered it was slightly inadequate, and 4 (3.6%) consid-ered it was very inadequate The prevalence of chronic diseases among subjects were hypertension (43.6%), cardiovascular disease (24.5%), diabetes (22.6%), hypercholesterolemia (12.7%), and arthritis (11.3%) Based on age-unadjusted CCI score, 63 older adults (54.8%) had a disease burden The average score of the ADL was 98.83, with a range of 97e99.6 The average IADL score was 22.68 (out of 24), with a range of 93%e97.50% of each item, indicating that majority of older adults with chronic conditions having intact physical functions The mean AD8 score was 1.56, and 40 subjects (34.7%) obtained scores equal to or greater than 2, indicating an early sign of dementia

3.1 Quality of life of older adults with chronic diseases The average QoL score of older adults with chronic diseases was 58.30 (out of 80), showing a medium level of QoL From each QoL dimension, the environmental category scored the highest, with an average of 15.02 (SD¼ 1.97), followed by the physiological health (14.69± 2.37) and the social relation (14.35 ± 2.23), whereas the psychological category scored the lowest, with an average of 14.21 (SD ¼ 2.42) For overall health satisfaction, 87 (77.9%) reached moderate or higher satisfaction regarding their health

3.2 Disability risk and health status of older adults with chronic diseases

Thefive components of disability risk assessment were move-ment, nutrition, cognition, social relations and depression Fifty-seven (49.6%) older adults obtained scores equal to or higher than

5, and a higher score indicated a higher risk of disability Nearly half (49.6%) of older adults with chronic diseases had a higher risk for disability (Table 1)

Correlational analyses among the socio-demographic charac-teristics, health status, disability risk, and quality of life of older

adults with chronic diseases Correlations between

socio-demographic characteristics and quality of life

The results showed that education level and economic

condi-tions (whether the income is adequate) of older adults with chronic

diseases were significantly correlated Older adults with a high

school or higher education showed significantly higher score in QoL

than did those who were illiterate/literate (self-study) in

physio-logical health (F ¼ 5.564, p < 0.05) and psychological status

(F¼ 4.678, p < 0.01) Regarding economic conditions, the adequacy

of income reached a significant level in the four aspects of QoL

Participants whosefinancial status were ‘more than sufficient’

re-ported higher QoL compared with those whosefinancial status was

‘sufficient’ or ‘slightly inadequate/very inadequate’ Results of

Pearson correlation analyses indicated that older people in age had

worsened QoL in the physiological health (r¼ 0.233; p < 0.05)

3.3 Correlations between health status and quality of life

The Pearson correlation analysis indicated that the ADL, IADL,

co-morbidity, and early sign of dementia were significantly

corre-lated with QoL, whereas the other variables were not Higher ADL

scores showed positive correlations with physiological health

(r¼ 0.372; p < 0.01), psychological status (r ¼ 0.433; p < 0.01),

social relations (r ¼ 0.228; p < 0.05), and environmental QoL

(r¼ 0.273; p < 0.01) The higher in IADL, the higher QoL were in

physiological health (r ¼ 41; p < 0.01), psychological status

(r¼ 0.41; p < 0.01), social isolation (r ¼ 0.26; p < 0.01), and

envi-ronmental QoL (r¼ 0.26; p < 0.01) A lower CCI score (age

unad-justed CCI score) indicated a higher psychological status

(r¼ 0.237; p < 0.05) A lower AD8 score indicated a more positive

QoL in physiological health (r¼ 0.465; p < 0.01), psychological

status (r¼ 0.546; p < 0.01), social isolation (r ¼ 0.391; p < 0.05),

and environmental QoL (r¼ 0.336; p < 0.01;Table 2)

3.4 Correlations between disability risk and QoL Pearson product-moment correlation was applied to analyze the correlations between risk for disability and QoL The results show that a sum of disability risk was correlated with QoL in physiolog-ical health (r¼ 0.609; p < 0.01), psychological status (r ¼ 0.521;

p< 0.01), and environmental domain (r ¼ 0.304; p < 0.01).Table 2

shows that the five disability risk domains, namely movement, nutrition, cognition, social relations, and depression, have signi fi-cant correlations with the QoL in physiological health, psycholog-ical status, social relations, and environmental factors, indicating that the fewer the disability risk were, the higher QoL was perceived

3.5 Predicting factors of the quality of life

To identify primary determinants affecting QoL, multiple linear regression models were conducted in three steps in order to examine the independent contributions of measures when entered together (Table 3) In thefirst step, economic status was found significant in explaining 10% of the variance in overall QoL (F¼ 10.50; p < 0.001) In the second step, the predictors with the most predicting power was an early sign of dementia, followed by physical function and the adequacy of the income These three variables effectively explained 39% of the variance in overall QoL (F¼ 19.79; p < 0.001) In the third step, the AD8 score was deter-mined to be the most effective predictor, followed by risk for depressive disability, income (more than sufficient), and risk for social relations disability These three variables effectively explain 49% of variance in overall QoL (F¼ 17.56; p < 0.001) The results show that, when controlling socio-demographic characteristics and health status, the differences between both risks of depression and social isolation and QoL were significant (Table 3)

Table 1

Risk of disability among older adults with chronic diseases (N ¼ 115).

Table 2

The correlations of sociodemographic characteristics, health status, risk for disability

on quality of life among older adults with chronic diseases (N ¼ 115).

Variables Physiological Psychological Social Environment

Sociodemographic characteristics

Health status

ADL a , b 0.372** 0.433** 0.228* 0.273**

IADL a , b 0.413** 0.408** 0.255** 0.261**

CCI b

Age adjusted CCI a , b 0.153 0.237* 0.147 0.111

AD8 a , b 0.465** 0.546** 0.391** 0.336**

Risk for disability

Overall a 0.609** 0.521** 0.174 0.304**

Movement a 0.472** 0.344** 0.174 0.304**

Nutrition a 0.394** 0.279** 0.116 0.258**

Cognition a 0.416** 0.362** 0.181 0.310**

Social a 0.298** 0.245** 0.139 0.203*

Depression a 0.394** 0.420** 0.202* 0.154

a *p < 0.05, **p < 0.01, ***p < 0.001.

b ADL ¼ activities of daily living; IADL ¼ instrumental activities of daily living;

CCI ¼ charlson comorbidity index; Age adjusted CCI score ¼ age adjusted charlson

comorbidity index score; AD8 ¼ alzheimer disease 8.

Table 3 Summary of hierarchical regression analysis predicting quality of life among older adults with chronic diseases (N ¼ 115).

Standardized regression coefficient

R 2 Standardized regression coefficient

R 2 Standardized regression coefficient

R 2

Sociodemographic characteristics

Level of education

①Primary/Junior High School/Junior

②High school more 0.040 0.060 0.060 The adequacy of the cost of living

①Sufficient and more than a

0.320** 0.10 0.023** 0.05 0.260** 0.04

Health status

③Age adjusted CCI score b

Risk for disability

F value a 10.500*** 19.790*** 17.560***

a *p < 0.05, **p < 0.01, ***p < 0.001.

b ADL ¼ activities of daily living; IADL ¼ instrumental activities of daily living; Age adjusted CCI score ¼ age adjusted charlson comorbidity index score; AD8 ¼ alzheimer disease 8.

3.6 Discussion

Based on the analysis, older adults with chronic diseases may

suffer from various diseases that lead to poor control of movement

and limit the performance of various activities Older adults are

therefore worried about themselves (physiologically and

psycho-logically), causing emotional distress that could generate negative

thoughts and feelings24,25

The regression analysis indicated that the AD8 score had the

most predictive power for older patients' QoL, which explains 27%

of the variance Empirical data concerning AD8 and QoL were

limited However, previous results have indicated that one of the

negative factors was cognitive impairment18,26

The IADL is also a crucial predictor of QoL The use of IADL is

appropriate for assessing the level of independence of older adults

with chronic diseases27 Previous studies have also indicated that

greater IADL functions in chronic patients indicate enhanced higher

QoL25

The stepwise regression analysis showed that risk for

depres-sion and social relations are primary factors related to QoL and

explain 14% of the variance Depression and social relations reflect

the QoL of patients with chronic diseases28,29 Faller et al.29

addressed that if depression issues are not emphasized, then the

quality of care cannot be improved, severely affecting

patient-s'prognosis and QoL will be followed

Our results have significant implications for clinical practice To

reduce the risk of disability conditions, it is necessary to strengthen

the patients' self-care ability, encourage them to participate in social

activities, focus on their mental health, and enhance their economic

conditions30,31 An increasing number of co-morbidities leads also to

a decrease of health-related QoL in older adults32 Therefore, to

maintain and to promote independent living of those with

disabil-ities, health care service system and the disability assessment tools

such as ADL, IADL, and AD8 are used to screen the elderly at high risk

of disability of activities of daily living and cognitive function12,33

The application of DALY index can also be applied to learn about the

diseases and control them from a macro perspective to make a

preliminary assessment of the existing measures so that limited

resources can have greater effectiveness34,11to increase the quality

of life among the elderly with disabilities35

We adopted purposive sampling and cross-sectional correlation

analysis, and the participants enrolled were limited to patients in a

medical center in Southern Taiwan In addition, DALY index was not

included Therefore, it is difficult to obtain comprehensive

reasoning and long-term discussion about the disability risks of

patients with chronic diseases If possible, a more rigorous

evalu-ation of the effectiveness can be conducted with experimental or

quasi-experimental design along with a longitudinal study design

for in-depth exploration of the ways DALY index can also be

included to help us adopting the best interventions to prevent the

priority disease, enhance the self-management of older adults,

improve their quality of life so as to decrease the risk of disabilities

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