East Asian Arch Psychiatry 2014;24:43-50

ORIGINAL ARTICLE

吳日嵐、潘佳雁、林智偉、A Leung

Prof. Petrus Ng, PhD, PsyD, RSW, Department of Social Work, Hong Kong Baptist University, Hong Kong SAR, China.
Dr Jia-Yan Pan, PhD, RSW, Department of Social Work, Hong Kong Baptist University, Hong Kong SAR, China.
Dr Paul Lam, PhD, PsyD, Occupational Therapist, Richmond Fellowship of Hong Kong, Hong Kong SAR, China.
Dr Alex Leung, PhD, California School of Professional Psychology, Alliant International University, San Francisco, California, United States.

Address for correspondence: Prof. Petrus Ng, Department of Social Work, Hong Kong Baptist University, Hong Kong SAR, China.
Tel: (852) 3411 5110; Fax: (852) 3411 7145; email: petrus@hkbu.edu.hk

Submitted: 11 July 2013; Accepted: 11 September 2013

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Introduction

Over the past few decades, there has been a change in the focus of mental health services from eradication of the disease to the enhancement of quality of life (QOL) of individuals living in the community with mental illness. There has also been a shift in the treatment paradigm from symptom management and relapse prevention to promotion of QOL.¹ With this shift, more emphasis is now placed on QOL as an outcome measure for treatments and programmes, as well as for determining resource allocations

The concept of QOL has become increasingly popular as an assessment factor in people with chronic mental health problems. However, it still remains ambiguous and controversial.³ In a basic sense, QOL refers to a means for quantifying one’s overall standard of wellbeing.⁴ It incorporates all aspects of an individual’s existence, including his / her success in obtaining certain expected or desired circumstances, states, or conditions.⁵ For people with chronic mental health problems, it is generally accepted that QOL is a multidimensional concept that relates to satisfaction with various aspects of life, including physical, social, and mental health functioning, as well as general health perception.⁶

Objective Versus Subjective Quality of Life

Quality of life comprises both objective and subjective elements.⁷ The objective elements of QOL include aspects external to a person’s experiential life, such as general health and functional and socio-economic status. These can be assessed objectively in a number of ways: (a) with biological, material, social, behavioural, and psychological indicators; (b) by objectively assessing daily activities and functioning⁸; (c) by measuring health status and material resources⁹; (d) with external life situations, such as social and economic indicators, behavioural competence, and role performance measures¹⁰; and (e) with biological factors.⁴ Chan and Yu³ also added the factors of attainment of resources and opportunities as an objective QOL measure.

Although objective data can help assess the health and functional status of an individual, these are considered inaccurate reflections of an individual’s wellbeing.¹¹ It is argued that measures of QOL assessment should include a significant subjective component as well.¹² The term ‘subjective’ implies that the evaluation of QOL depends on the individual who is living that life. It should be based on an individual’s point of view,¹³ self-rating,¹² or interview. Thus, any assessment of one’s objective life condition has to take account into the individual’s scale of value. Subjective QOL has become increasingly popular as an outcome measure to evaluate health services in clinical practice.¹⁴

In general, the subjective QOL experience for any individual is dynamic and subject to change. Thus, it may vary with time and with a number of other personal and environmental factors.¹⁵ These factors may include: (a) age¹⁶; (b) gender; (c) ethnicity; (d) culture¹⁷; (e) presence of illness¹⁸ and the type of illness; (f) financial status; and (g) societal influence.¹⁹

Quality of life is considered a multidimensional concept,⁸ consisting of a number of different dimensions.¹⁹ Some researchers have proposed that QOL be divided into at least 3 major dimensions: physical, psychological, and social.¹⁹ Other researchers have proposed 5 categories for the assessment of QOL: physical health, mental health, work, social life, and home and family.²⁰ Within these different proposed models for assessing QOL, there are overlapping dimensions. A more widely used version of a 4-dimensional categorisation of QOL was suggested by the World Health Organization (WHO) in 1998²¹ which comprised physical health, psychological health, social relationships, and environmental dimensions.

Efforts to measure QOL were first undertaken in the US in 1997.²² The measurement of QOL was first applied in medical practice and was used to prove that cancer treatment could improve patients’ sense of wellbeing apart from improving their survival rate.²³ In 1985, researchers in the UK working in the fields of social and health care started to adopt QOL measures for their clients.²⁴ Over the past few decades, various measures of QOL have been developed⁴ with a complex collection of items, scales, domains, and instruments.²⁵

Quality of life in People with Mental Illness

Different factors have been reported with regard to the subjective QOL of people with chronic mental illness. However, due to the many differences in the study designs, including selection and size of the samples, characteristics of the settings, and assessment procedures and instruments used, there are no conclusive findings regarding the impact of socio-demographic factors on QOL.¹⁴ Nonetheless, a correlation has been found between QOL of individuals and clinical factors, such as severity of psychopathology, duration of illness, and number of hospitalisations.²⁶ In some studies, participants with mental health problems were found to be most dissatisfied in the areas of finance and personal safety, work, contacts with others, money, and mental health.²⁷ The length of illness and duration of hospitalisation were also reported to be associated with subjective QOL.¹² Nevertheless, the determinants of QOL of Chinese people with chronic mental illness might be different as Chinese culture places more emphasis on the Confucius values of group harmony and interpersonal connection. While there are many publications on subjective QOL in mental illness, those findings might not be relevant in Chinese societies, particularly in the domain of self- rated social support²⁸ of persons with mental illness who are living independently in the community and receiving Community Mental Health Care (CMHC) services in Hong Kong. The CMHC is a new programme set up in 2005 to provide support services for people with mental illness after getting discharged from hospitals or halfway houses, and who are deemed to be in a stable mental condition. These services, which are primarily delivered by social workers from non-governmental organisation (NGO), include: (a) providing counselling and developing an individual rehabilitation plan; (b) providing training in social and communication skills, work skills, and daily living skills such as budgeting and home management; (c) facilitating sheltered work / job placement; and (d) making referrals to other welfare services.²⁹

Methods

Participants and Procedures

This study attempted to understand the QOL profile of people with chronic mental illness living in the community and receiving CMHC services, and identify factors that affect their QOL. It was hypothesised that demographic and clinical variables would affect their QOL. Convenience sampling was used to recruit the participants.³⁰ The participants had to meet the following inclusion criteria: (a) diagnoses of mental disorders³¹; (b) having been discharged from psychiatric hospitals or halfway houses and were living in the community; (c) aged between 15 and 70 years; and (d) were receiving CMHC services. The exclusion criteria for the participants included: (a) subjects with a history of violence, or with priority follow-up status (those in need of intensive medical treatment); and (b) patients with co-morbid diagnoses of substance abuse, organic brain syndromes, or mental retardation. This study focused on QOL of people who were not in acute stage of mental illness. There are 2 major reasons for excluding people with a history of violence or priority follow-up. First, these patients were usually required to attend special services, such as special halfway houses, or need intensive medical care. Many of them were not available for this study. Second, such people usually required more interventions from the mental health professionals in relation to a history of violence or priority follow-up when compared with other patients with mental illness. They may, therefore, have different rehabilitation experiences that may affect their QOL as compared with those with mental illness without a history of violence.

The study protocol was approved by the research committee of the Hong Kong Baptist University. The study proposal was also sent to the directors of NGOs and was approved by their research committees. After obtaining oral consents from the potential participants and with the assistance from the social workers of the NGOs, individuals who met the inclusion criteria were contacted via telephone and invited to participate in the study. The face-to-face interviews were conducted in the interview rooms of the NGOs.

Instruments

Each participant completed 2 questionnaires in face-to-face interview: the Hong Kong Chinese version of the World Health Organization Quality of Life Brief questionnaire (WHOQOL-BREF-HK) and a socio-demographic questionnaire.

The WHOQOL-BREF-HK is a Hong Kong Chinese version of the WHOQOL-BREF.³¹ It was developed in 1998 through the collaboration of the Hospital Authority of Hong Kong and the WHO. The WHOQOL-BREF-HK is used to measure the QOL in the subjective sense, and covers 4 major domains or subscales with respect to QOL: physical health (DOM1), psychological health (DOM2), social relationships (DOM3), and environment (DOM4). Two additional cultural-specific questions were also added to the questionnaire, including question 27 (“To what extent do you feel other people accept you?”) and question 28 (“How easy is it for you to eat the food you desire?”). The WHOQOL-BREF-HK has demonstrated satisfactory psychometric properties with Cronbach’s alphas of 0.77 (DOM1), 0.78 (DOM2), 0.59 (DOM3), and 0.76 (DOM4). The test-retest reliability ranged between 0.80 and 0.91.³²

The socio-demographic questionnaire included questions on gender, employment status (employed or unemployed), marital status (single, married, divorced, separated), age, education level, length of mental illness, onset of mental illness, and number of hospitalisations. With respect to employment status, vocational rehabilitation services, such as day hospital, sheltered workshop, or supported employment were considered equivalent to being employed.

Results

A total of 105 individuals were recruited for the study. These individuals were predominantly Cantonese-speaking Chinese adults who were receiving CMHC services from 2 NGOs in Hong Kong. Among these, 46 (44%) were male and 59 (56%) were female. The majority of participants (71%) were living with their families and the rest (30%) were living alone or with friends in apartments or compassionate housing, a form of housing assistance provided by the Housing Authority of Hong Kong. The mean age of the participants was 40 years (range, 18-70 years). The mean (± standard deviation) age of male participants were slightly younger (39.4 ± 12.1 years) than the female participants (40.0 ± 12.5 years). The majority of the participants (n = 54; 51%) were in the age-group of 36 to 55 years. Also, 73% of the participants in this study had had their mental disorder for a long period of time, with a mean of 10.7 years.

About half (49%) of the participants were single, and 60% (n = 63) had received a secondary level education. The proportion of participants who had received post-secondary or university education prior to the onset of mental illness (12%) was significantly lower than that in the general population (25%).³³ Very few of the participants (6%) were illiterate. Of note, many of these illiterate participants were older (≥ 55 years) and might have been immigrants from Mainland China who did not have any opportunity to receive an education.

Less than half of the participants (43%) were employed in the conventional job market. Using the special criteria of employment for this study, such as engagement in different sheltered work or assisted employments like day hospital, sheltered workshop, and supported employment, the majority of the participants (85%) could be considered as being employed at the time of the study. Only 15% of participants were unemployed or unattached to occupation training services.

The majority (60%) of the participants reported to have schizophrenia. Of the remaining participants, 31% reported to have depression, 2% had personality disorders, and 7% reported to have other disorders. All participants had been hospitalised at least once; 74% (n = 78) reported only 1 hospital admission before the time of the study. Their mean duration of illness was 10.7 ± 10.3 years, whereas the duration in males was slightly longer (11.5 ± 9.9 years) than the females (10.1 ± 10.7 years; p = 0.05).

The majority (70%) of participants reported having the illness for < 10 years; 18% reported having the illness for 10 to 20 years, 11% reported having the illness for > 20 years, and another participant (1%) had the illness for < 1 year. The age at onset of the illness ranged from 11 to 66 years, with a mean of 29.6 ± 12.1 years. The mean age at onset of illness in male participants (28.4 ± 12.9 years) was lower than that of the female participants (30.6 ± 11.4 years; p = 0.05). The duration of illness was closely related to the chronicity and severity of the illness, a factor that could affect the QOL of the participants.

Data from the WHOQOL-BREF-HK were analysed for each of the 4 QOL domains to give the following Cronbach’s alphas: DOM1 (0.43), DOM2 (0.70), DOM3 (0.63), and DOM4 (0.78). The mean ratings of the 4 domains were: DOM1 (12.7 ± 2.4), DOM2 (11.5 ± 3.2), DOM3 (12.2 ± 2.7), and DOM4 (12.3 ± 2.5).

Table 1 shows the findings from one-way analysis of variance (ANOVA) comparing the types of mental illnesses with the QOL of participants. There were significant differences among the participants based on their diagnoses and the total QOL (F = 4.44, p = 0.01). Furthermore, there were significant differences between the mean scores of subjects with different types of mental illnesses (DOM1 [F = 4.94, p < 0.001], DOM2 [F = 4.84, p < 0.001], and DOM4 [F = 2.79, p = 0.04]).

Correlational Analysis

The correlations between socio-demographic and clinical variables and QOL are shown in Table 2. The duration of illness was found to have a significant positive correlation with total QOL (r = 0.25, p = 0.02) and in particular with the 3 domains of DOM1 (r = 0.20, p = 0.04), DOM2 (r = 0.27, p = 0.01), and DOM4 (r = 0.28, p = 0.01).

The age at onset of illness was significantly correlated with total QOL (r = –0.24, p = 0.02) as well as the 3 domains: DOM1 (r = –0.25, p = 0.01), DOM2 (r = –0.23, p = 0.02), and DOM4 (r = –0.25, p = 0.01).

The one-way ANOVA indicated that there was significant difference between type of mental illness and the participants’ overall QOL (F = 4.44, p = 0.01). Tukey’s HSD test was used to test for group differences, and it was found that the outcome of participants within the schizophrenia and psychotic disorder group was different from that in the mood disorder group (p = 0.01). Participants with schizophrenia and psychotic disorders had significantly better QOL than participants with mood disorders (Table 3).

The one-way ANOVA was conducted with each domain of the QOL. There was significant difference in the mean scores between types of mental disorders for DOM1 (F = 4.94, p = 0.003) and DOM2 (F = 4.84, p = 0.003). Post-hoc tests were conducted to test the group differences for the 2 domains. For DOM1, significant difference was found between the schizophrenia / psychotic disorder group and mood disorder group (p = 0.05), the mean score of the former was higher (13.0 ± 2.2) than the latter group (11.7 ± 2.4). Moreover, the DOM1 score in personality disorder group was significantly lower (9.3 ± 4.6) than the other disorder group (14.3 ± 2.5; p = 0.04). Regarding DOM2 scores, significant difference was only found between the schizophrenia / psychotic disorder group (12.1 ± 2.9) and the mood disorder group (10.3 ± 3.0; p = 0.04).

A stepwise regression on the 4 domains of QOL showed that duration of illness and age at onset accounted for a small portion of variance in QOL (Table 4). Duration of illness accounted for only 6% of the variance in the total QOL (F = 5.77, p = 0.02) and only 5% of the variance in physical health (F = 6.08, p = 0.02). In addition, duration of illness only accounted for only 9% of the variance in psychological health (F = 9.31, p = 0.003).

Discussion

We found a higher proportion of unmarried male (65%) in this study. In Hong Kong, many men with chronic mental illness, who have few financial and social abilities and resources, find it difficult than women to find a life partner. Many men with mental illness are forced by society to remain single because they cannot financially support a family. However, women with a mental illness in Hong Kong have better prognosis than men with mental illness,³⁴ and one could argue that better prognosis will likely increase one’s chances to marry. The employment rate of the participants was highly consistent with the findings from another study on hospital and community-based care for patients with chronic schizophrenia in Hong Kong.¹

Many of the participants in this study worked in sheltered workshops or in assisted employment with relatively low pay. This finding that people with chronic mental health problems live on the margin of society has been corroborated from studies conducted in other countries³⁵ as well as in Hong Kong.³ For many people with chronic mental illness working in assisted employment, the earnings are not sufficient to cover their subsistence needs. Thus, many live in poverty and cannot afford social activities.³

In general, the participants had a lower level of total QOL as well as lower scores on each of the 4 domains than the general population and psychiatric patients of Hong Kong.³⁶ These findings, which are consistent with data from studies in other countries³⁷ and local studies,^3,14 suggested that people with chronic mental illness are generally less satisfied with their QOL than the general population.

With regard to the areas of dissatisfaction, the participants in this study were most dissatisfied with their financial situation, possibly as a result of their low-paying jobs or limited general financial resources. Their financial hardships may well have affected their physical and social lives and impacted their overall enjoyment of life and attitude towards the meaning of life.

Another dissatisfaction reported was pain and discomfort, and this may possibly be related to the side-effects of antipsychotic medications. Subjects on antipsychotic medication often need to tolerate pain and discomfort associated with these medications over a long period of time. These side-effects — which may include extrapyramidal, anticholinergic, antiadrenergic, tardive dyskinesia, and antihistaminergic symptoms — negatively influence their subjective QOL.²⁶

There was no conclusion drawn regarding the effect of family support on QOL. However, family could also have a negative effect on individuals with mental illnesses because of a negative emotional climate in the family. The quality of relationships within the family could influence an individual’s social and emotional functions. The quality of family relationships was negatively influenced by the length of mental illness of the patient. In this study, the mean length of illness of the participants was 10.7 years, indicating that many families of the participants had been coping with the illness for a long period of time. Consequently, they may have become weary of the caregiving tasks.

With regard to clinical variables, participants with schizophrenia or psychotic disorders were found to have significantly higher QOL, particularly in physical and psychological domains than those with mood disorders and other disorders. Although the symptoms of schizophrenia, such as hallucinations and paranoid ideas, could affect one’s sense of security and various aspects of daily living and social functioning, people with depressed mood might report a relatively lower subjective QOL score as they are affected by their pessimistic view about themselves. However, the causal association between type of illness and QOL could not be inferred from this study, and, thus, deserves further investigation.

Stepwise regression showed that duration of illness predicted the total QOL and psychological health. Participants with longer duration of illness were found to have a significantly higher total QOL score, and in particular, psychological health. Quality of life is often related to the prognosis of the illness, and long duration of illness is often regarded to have negative effects on the prognosis. Thus, our finding is in contrast with the widely accepted view that the longer the duration, the poorer the prognosis of the illness.³¹ Perhaps this discrepancy might be due to an inherent qualitative difference between the QOL of a patient and the prognosis of the illness.

In this study, QOL refers to subjective experience and how an individual evaluates his / her own ability to cope with living with the illness. This subjective attitude may be completely unrelated to the objective evaluation of prognosis of illness by a psychiatrist. Individuals with chronic mental health problems, regardless of the prognosis, might maintain a subjectively high QOL. Moreover, some might become more content with their lives after suffering from the illness for many years. Early in the illness, the effects of both the positive and negative symptoms may have a strong impact on the individual’s social functioning. However, over time, they may adapt to their symptoms as well as living with the illness. In this study, many of the participants might have ceased to be defined by their illness, seldom refer to it, and do not show any particular dissatisfaction with their lives.

Age at onset of the illness is another clinical variable correlated with physical health, and stepwise regression showed that the age at onset was predictive of physical health. Improved physical health was significantly correlated with early onset of mental illness. However, age at onset was the least significant contributing factor relating to chronic mental health problems. This finding was inconsistent with data from previous studies^1,3 which showed that people with chronic mental health problems living independently in their community were most satisfied with their physical health and, in particular, their mobility.

This study also has some limitations. First, the sample size of the study was quite small. Second, the researchers had to adopt a convenience sampling based on the availability of the participants as they were invited voluntarily for the interview. Thus, the sampling was not exactly random in nature.

The third limitation was related to the participants of this study. This study excluded those with a history of violent behaviour or priority follow-up status. Thus, the study might not be truly representative of the people with mental illnesses in Hong Kong.

Finally, this study was a cross-sectional analysis to evaluate the QOL of people with chronic mental illness living in the community. It did not test the causal linkage between different socio-demographic and clinical factors and QOL in patients whose treatments changed and who underwent rehabilitation. There is a need to develop longitudinal studies to test the causal relationships between these factors and the QOL of patients who are recovering.

Implications for Services and Future Research

The concept of QOL has become an important consideration in the rehabilitation of patients, as it is regarded as an important indicator of good health status and positive rehabilitation.⁶ Is it important to find new ways to enhance the QOL of people with chronic mental illness?

The ability to obtain gainful employment with reasonable pay is necessary for all individuals, including those with mental illness, as it paves the way for other life pleasures and the ability to live a normal life. In view of the relatively high proportion of people with mental illness who attained secondary education level, it would be helpful for mental health professionals to become more knowledgeable about skill-based vocational training programmes to prepare their patients for gainful employment in the future, independent of social services. However, those who cannot be gainfully employed could get help from mental health professionals to develop meaning of life from non-paid activities, such as leisure and voluntary work.

In this study, clinical factors, such as duration of illness and age of onset, played a more important role in QOL than socio-demographic factors. Despite this, the clinical factors explained only 5% to 9% of the variance. Clearly, there must be other predicting factors for QOL, such as the social network of the patient, leisure, and spiritual support that deserve further investigation.

In practice, there is a need to identify ways to enhance social and supportive network for people with mental illness. Mental health professionals could organise self- help or support groups to assist their patients in developing a good social support network to sustain their living in the community. Family members also need assistance to help them cope with caring for their family members with mental illnesses. Family education in conjunction with a mutual supportive network should be organised to foster supportive attitudes and enhance a pro-social family attitude as part of rehabilitation programmes for people with mental illnesses.

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