Schizophrenia is a severe and persistent mental illness, affecting approximately 1% of the world's population (Clark, 2016). According to the Chinese Ministry of Health, Ministry of Civil Affairs, and Ministry of Public Security and Disabled Persons Federation (2002), there are 16 million individuals in China with severe mental illness, including 7.8 million with schizophrenia. Patients with schizophrenia experience symptoms, stigma, disability, unemployment, and reduced quality of life (QOL) (Wilkinson et al., 2000).
With advances in the pharmacological treatment of acute psychiatric symptoms in schizophrenia over the past 20 years, QOL measurements have become an important way to evaluate the treatments and care provided to patients with schizophrenia (Alessandrini et al., 2016). Determinants of QOL in individuals with schizophrenia have been extensively reported, including demographic and clinical variables, and psychosocial characteristics such as social support, stigma, self-esteem, and social functioning (Hsiao, Hsieh, Tseng, Chien, & Chang, 2012). Among these impact factors, psychosocial determinants are more preventable for nurses but have not been fully explored.
One important factor that affects QOL of individuals with severe mental illness is self-stigma (Corrigan, Rafacz, & Rüsch, 2011). Schizophrenia has been found to be one of the most stigmatizing conditions (Angermeyer & Schulze, 2001). Those with mental illness and their families often state that the stigma associated with their diagnosis is more difficult to bear than the actual illness (Happell & Gough, 2009). Self- or internalized stigma exists at the individual level and refers to the process by which individuals with mental illness apply negative stereotypes to themselves, expect to be rejected by others, and feel alienated from society (Parker et al., 2013). The harmful effects of stigma on the lives of individuals with mental illness are thoroughly documented in the literature. Internalized stigma has been associated with decreased self-esteem and self-efficacy, hopelessness, reduced feelings of empowerment, poor QOL, depression, impairments in vocational functioning, and reduced treatment adherence (Gerlinger et al., 2013; Lysaker, Roe, & Yanos, 2007).
Another key variable influencing QOL for outpatients with schizophrenia is their empowerment (i.e., their strengths and the ability to sustain control over their life) (Sibitz et al., 2011). In the past two decades, implementation of empowerment in community mental health has increased. The growing emphasis on empowerment reflects a newer conception of the goals of mental health services and self-involvement for outpatients with mental illness (Chou et al., 2012). Empirical studies have shown that empowerment is positively associated with QOL, social support, self-confidence, and self-esteem (Sakellari, 2008), and negatively associated with severity of psychiatric symptoms (Roth & Crane-Ross, 2002). A focus on personal empowerment encourages patients to actively manage their psychiatric symptoms, make choices about the development and implementation of their treatment, and develop a positive sense of self (Glynn, 2003; Hansson & Björkman, 2005).
One aspect of QOL that has not been fully explored is the role of uncertainty in illness of individuals with schizophrenia. Uncertainty in illness is defined as the “inability to determine the meaning of illness-related events when the patient cannot determine the value of events or cannot accurately predict the disease outcome due to the lack of sufficient cues” (Mishel, 1981, p. 258). State of uncertainty is a major component of all illness experiences and affects psychosocial adaptation and outcomes of disease. Increasing uncertainty results in less problem-oriented coping, more emotion-oriented coping, and poorer QOL (Reich, Johnson, Zautra, & Davis, 2006). Some individuals with schizophrenia experience differing degrees of uncertainty (Baier, 1995). A study on Chinese patients with schizophrenia found that most (92.1%) experienced moderate or higher levels of uncertainty in illness (Zhong & Cai, 2014). Thus, it is important to explore the relationship between illness uncertainty and QOL in patients with schizophrenia.
In addition, psychiatric symptoms (especially negative symptoms) are consistently found to be paramount factors that affect QOL in individuals with schizophrenia (Fontanil-Gómez, Alcedo Rodríguez, & Gutiérrez López, 2017). However, symptom reductions alone often do not result in meaningful improvements in QOL because other problems, such as lack of social contacts, uncertainty of illness, and stigmatization, remain. Psychosocial interventions are now universally accepted as an integral part of the comprehensive management of schizophrenia. Only by having a clear understanding of the determinants of QOL can rational and cost-effective strategies be developed (Yeung & Chan, 2006).
The specific objectives of the current study were to: (a) examine the relationships among demographic characteristics, psychosocial variables, symptom severity, and QOL as perceived by individuals with schizophrenia; and (b) identify predictors of QOL for those with schizophrenia living in the community.
A cross-sectional research design was used. The study was conducted with the approval of the Ethics Committee of Wuhan University in China. After having received information about the aim of the study, participants were asked to sign an informed consent form. Anonymity was assured and it was made clear that participants could withdraw from the study at any time. Participants received a small gift once questionnaires were completed as a means of thanking them for their time and effort.
Recruitment and Data Collection
A convenience sample of individuals with schizophrenia was recruited from several community mental health centers in Wuhan, China. Recruitment of participants was conducted by the first author (C.C.), who visited the centers twice per week and contacted all suitable patients. Inclusion criteria were: having a case record diagnosis of schizophrenia, outpatient treatment, providing informed consent, being clinically stable and not aggressive or hostile, having sufficient cognitive capacity, and capable of communicating in Chinese. Exclusion criteria were having coexisting mental retardation, dementia, or other severe organic disorders, or drug or alcohol dependence.
Participant demographics that were collected included age, gender, marital status, education, occupation, and disease-related information, including duration of illness and medications.
Perceived stigma was measured using the Internalized Stigma of Mental Illness Scale (ISMI; Ritsner, Kurs, Gibel, Hirschmann, & Shinkarenko, 2003), which contains 29 Likert items rated on a 4-point agreement scale (where 4 = strongly agree); higher scores indicate greater self-stigma. The ISMI is a self-report questionnaire designed to measure the internalized, subjective experiences of stigma for individuals with mental illness. It comprises five subscales: alienation, stereotype endorsement, discrimination experience, social withdrawal, and stigma resistance. An overall score (i.e., the sum of all items with stigma resistance items being reversed) was used for analyses. Previous research has demonstrated excellent internal consistency with the ISMI total score (Livingston & Boyd, 2010). Internal consistency of the scale in the current study was 0.87.
Personal empowerment was measured using the Empowerment Scale (Rogers, Chamberlin, Ellison, & Crean, 1997), which is a 4-point Likert scale ranging from strongly agree to strongly disagree. Total scores range from 28 to 112, with higher total scores indicating better feelings of empowerment. The scale has been demonstrated to have adequate internal consistency and good factorial validity, as well as adequate construct validity (Sibitz et al., 2011), which comprises five factors: self-efficacy/self-esteem, power/powerlessness, community activism, righteous anger, and optimism–control. Cronbach's alpha was 0.85 in the current study.
Illness uncertainty data were collected using the Mishel Uncertainty in Illness Scale (MUIS; Mishel, 1981), which was designed to measure patients' perceptions of uncertainty about their symptoms, diagnoses, treatment, prognosis, and relationship with caregivers. The MUIS has four subscales: illness uncertainty, focusing on ambiguity, and complexity and unpredictability of symptoms. As done in previous studies (Parker et al., 2013; Reich et al., 2006), the current authors combined these subscale scores into a single total score. Higher scores indicate greater illness uncertainty. Items were recorded on a 5-point scale, where 1 = strongly disagree to 5 = strongly agree. Cronbach's alpha was 0.87 in the current study.
The 18-item Brief Psychiatric Rating Scale (BPRS; Overall & Gorham, 1962) was used to assess the presence and severity of psychiatric symptoms. Each item is rated on a 6-point scale ranging from not present to extremely severe, with higher scores representing a higher level of mental symptoms (total score range = 0 to 108). Cronbach's alpha was 0.8 in the current study.
QOL was measured using the Schizophrenia Quality of Life Scale (SQLS; Wilkinson et al., 2000), which is a disease-specific instrument for patients to assess the effect of schizophrenia on their lives. It is a self-reported, 30-item questionnaire for measuring QOL specific to patients with schizophrenia, requiring 5 to 10 minutes to complete. The SQLS is a 5-point Likert-type scale where 1 = never to 5 = always, with higher scores indicating worse QOL. It comprises three subscales: psychosocial (15 items), motivation and energy (7 items), and symptoms and side effects (8 items). Lower scores indicate higher levels of subjective QOL. Reliability and validity of the Chinese version of the scale have been found acceptable (Luo, Seng, Xie, Li, & Thumboo, 2008).
SPSS 14.0 was used to analyze data. Patient characteristics were analyzed using descriptive statistics. Pearson correlations were used to test associations between the variables of interest. Variables with a significant relationship with QOL (p < 0.05) were then used in stepwise multiple regression analyses to investigate the relative importance of these variables as determinants of QOL. The one-sample Kolmogorov–Smirnov test was used as a goodness-of-fit test to investigate the distributions of the variables. The results of this test indicated that the distributions of these measures were relatively normal (p > 0.05).
Ethical approval was obtained from, and conducted in accordance with, the Research Ethics Committee of Wuhan University and the community mental health centers from which potential participants were approached about the study. A consent form was used and researchers explained the purpose, method, and process of the study to patients and their families, and clearly stated that they had the right to withdraw at any time before obtaining this consent. Responses were recorded on each respective questionnaire. Researchers also clarified that all information collected would be treated as anonymous and confidential.
One hundred seventy-eight individuals with schizophrenia were recruited from several community mental health centers in central China. Of these, 172 completed the survey (96% response rate). This sample size can detect correlations between variables with a medium effect size at the power of 0.80, alpha of 0.05, and p value of 0.05 (Cohen, 1992). Participants' ages ranged from 18 to 65 years (mean = 43.1 years, SD = 10.7 years) with a mean illness duration of 14.5 years. Approximately 61% of participants were male; 39% were female. Mean years of education was 11.25 (SD = 2.15 years, range = 6 to 18 years). Most participants were single, with only 25% having an intimate relationship. Overall, 23.5% of participants lived unsupervised in a home/apartment and 26.5% resided in some type of supervised living arrangement. In addition, 96.6% received disability benefits and 9.4% reported a current paid job. Mean number of previous hospitalizations was 5.2 (SD = 5.5). Mean age at mental illness onset was 25.1 years (SD = 5.81 years). All participants took medications. No significant SQLS score differences existed between demographic items, except in employment status (p = 0.03) and monthly household income (p = 0.01). Mean total score for the SQLS was 21.54 (SD = 11.62). Mean scores for perceived stigma, personal empowerment, uncertainty in illness, and the BPRS were 92.65 (SD = 15.55), 66.88 (SD = 11.56), 99.56 (SD = 7.55), and 86.79 (SD = 10.32), respectively.
Significant correlations were found among variables, except for uncertainty with symptom severity and the SQLS (Table 1). Pearson's correlations ranged from 0.11 to 0.69. Personal empowerment was positively correlated with employment status (r = 0.112, p < 0.01) and monthly household income (r = 0.231, p < 0.01), and negatively and significantly correlated with uncertainty (r = −0.412, p < 0.001), perceived stigma (r = −0.323, p < 0.01), and symptom severity (r = −0.551, p < 0.001). Empowerment, followed by symptom severity, stigma, income, and employment status, had the highest strength of correlation with total SQLS score. Variance of total SQLS score can be explained by 47.88%, 29.16%, 16.81%, 9.67%, and 5.38% of these variables, respectively.
Correlation Coefficients among Major Variables (N = 172)
Predictors of Quality of Life
The variables that correlated significantly with the global SQLS in the univariate analysis were entered in a stepwise multiple regression analysis with total QOL. Employment status, annual family income, perceived stigma, personal empowerment, symptom severity, and uncertainty in illness were used as independent variables. The variable of employment status is dichotomous and coded 1 if the patient was employed or 0 if unemployed or retired, and annual family income is a categorical variable that was coded from 1 to 3, where 1 = <1,000 yuan/month, 2 = 1,000 to 2,000 yuan/month, and 3 = >2,000 yuan/month. The most important factor related to QOL was empowerment (Table 2). Better empowerment was related to better QOL, accounting for 22.1% of variance. A smaller contribution of 7.6% was made by symptom severity—the two in total accounting for 29.7% of variance.
Stepwise Multiple Regression of the Predictors of Quality of Life (N = 172)
Consistent with previous studies (Hsiao et al., 2012; Sibitz et al., 2011), sociodemographic factors (e.g., monthly household income, employment status) were found to be significantly correlated with QOL among community-dwelling patients with schizophrenia. In addition, greater symptom severity of an illness is associated with decreased QOL, which has been confirmed in a variety of populations (Kao, Liu, Chou, & Cheng, 2011; Priebe et al., 2011). Previous findings concerning the relationship between symptom severity and QOL in this population of individuals with schizophrenia have been mixed and generated inconsistent results. For example, research examining QOL of individuals in the early course of schizophrenia has indicated that psychiatric symptoms may be more influential to QOL compared with more chronic populations. Narvaez, Twamley, McKibbin, Heaton, and Patterson (2008) found that positive symptom severity does not predict subjective or objective QOL, but that negative and depressive symptoms play an important role in QOL. The current sample, which was in a comparatively stable condition (i.e., few positive symptoms), might partly explain the nonsignificant relationship between symptom severity and QOL.
It has been hypothesized that illness uncertainty is related to QOL in individuals with schizophrenia (Parker et al., 2013), but this was not found true in the current sample. Studies of patients with cancer (Jeon, Choi, Lee, & Noh, 2015) and chronic illness (Caruso, Giammanco, & Gitto, 2014) found uncertainty can lead to reduction in QOL and the ability to cope with illness. Some researchers encourage professionals to provide patients clear and consistent information, thereby reducing illness uncertainty (Lin et al., 2013). The current results suggest that this concept must be used with caution in psychiatric nursing. Providing patients information about the disease is widely accepted in Eastern culture, but may not be fully accepted or practiced in Chinese culture. In China, many individuals have a pessimistic, incurable belief about schizophrenia, and cannot accept that schizophrenia is a chronic, lifelong illness (Zhong & Cai, 2014). Baier (1995) showed that for some individuals with schizophrenia, uncertainty provided the opportunity for hope, whereas for others the uncertainty was perceived as a danger. Other studies have indicated that illness uncertainty is associated with positive and threatening outcomes (Hilton, 1994; McCormick, 2002). Different measures of illness uncertainty, heterogeneous samples, and whether to consider uncertainty independently or other variables simultaneously may account for the inconsistency. How an individual endows meaning to an uncertain situation and how uncertainty can be transformed into a positive or negative outcome is unclear and requires further study. The types of situations in which health professionals should intervene to eliminate uncertainty or when interventions should be implemented to promote uncertainty for individuals with schizophrenia are unknown. Different perspectives must be applied to achieve a fuller understanding and further research is needed to determine the relationship between uncertainty and other psychosocial variables, such as coping, perceived control, social support, and QOL.
The current results confirm that perceived stigma is negatively correlated with personal empowerment and QOL in individuals with schizophrenia. This finding is consistent with previous findings that stigma plays an obstructive role in QOL in community-dwelling individuals with mental illness (De Hert et al., 2011). Regarding personal empowerment, significant positive relationships were found with QOL. Negative correlations were found with symptom severity, stigma, and illness uncertainty. These findings were consistent with those in most international studies (Tolman & Kurtz, 2012). Regression analysis identified the relative importance of personal empowerment as a determinant of QOL. Among all variables, personal empowerment was the best positive predictor, whereas symptom severity was the best negative predictor, of QOL in patients with schizophrenia. Although perceived stigma was significantly correlated with QOL, when all variables were taken into account, stigma did not factor into the regression equation, which may indicate that the effect of stigma on QOL is explained by empowerment. For example, Sibitz et al. (2011) noted that although stigma and lack of empowerment impair QOL, having some degree of internalized stigma does not inevitably impede well-being if accompanied by high empowerment. Hwang et al. (2009) found that although cross-sectional analyses revealed a moderate, negative relationship between self-stigma and QOL, longitudinal analyses indicated that self-stigma was not a significant predictor of QOL. Finally, the regression model explained only 25.2% of the variance; therefore, there may be other variables, such as a patients' coping style, social support, or community orientation, which have not been considered sufficiently in the current study.
The current study has some limitations. First, the cross-sectional design limited conclusions regarding causality. The second limitation is lack of reliability of the self-report methodology. A third limitation is that participants were recruited from several community mental health centers located in central China using convenience sampling. The findings cannot be generalized to all patients with schizophrenia in China.
Relevance for Clinical Practice
The current findings have implications for community health care. Although symptom management is necessary for community-dwelling individuals with schizophrenia, reducing perceived stigma and enhancing patient empowerment is more important for this population. Many factors that influence QOL in this population are not readily amenable to change (i.e., employment). Interventions directed toward enhancing empowerment and managing stigma are comparatively reasonable to help improve QOL in these patients. Health care professionals should consider patient interventions targeted toward personal empowerment to improve QOL for individuals with schizophrenia. An empowerment rehabilitation program should provide patients with flexible social environments that provide security, as well as interactions that promote individual growth, formation of identity, competence, and a meaningful relationship with peer groups (Freund, 1993). Mental health nurses may develop and implement adequate psychosocial rehabilitation activities to facilitate decision-making skills and promote self-esteem by providing assertive training or creating opportunities to improve social skills for individuals with schizophrenia (Chou et al., 2012).
The current study investigated the relationship among sociodemographic characteristics, symptom severity, and psychosocial determinants (e.g., self-stigma, empowerment, uncertainty of illness), and their comparative contribution to affecting QOL in community-dwelling patients with schizophrenia. The results indicate that QOL in this population is significantly correlated with perceived stigma and symptom severity and personal empowerment. When all psychosocial determinants were considered, personal empowerment was the best positive predictor of QOL in patients with schizophrenia. Implications for mental health nursing are that interventions targeted toward personal empowerment may improve QOL in this population.
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Correlation Coefficients among Major Variables (N = 172)
|Variable||Employment Status||Income||Empowerment||Stigma||Uncertainty||Symptom Severity|
|Quality of life||0.232**||0.311**||0.692***||−0.41**||0.019||−0.54***|
Stepwise Multiple Regression of the Predictors of Quality of Life (N = 172)a
|Variable||R2 Change||F Change||Final Beta||p Value|