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Association between poverty and psychiatric disability among Chinese population aged 15–64 years
Psychiatry Research 200 (2012) 917–920
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Psychiatry Research journal homepage: www.elsevier.com/locate/psychres
Association between poverty and psychiatric disability among Chinese population aged 15–64 years Ning Li, Lihua Pang, Wei Du, Gong Chen, Xiaoying Zheng n Institute of Population Research, No. 5, Yiheyuan Road, Haidian District, Peking University, Beijing, China
a r t i c l e i n f o
abstract
Article history: Received 11 September 2011 Received in revised form 14 May 2012 Accepted 24 May 2012
Psychiatric disability is an important public health problem in China, and poverty may be positively correlated with disability. Little study in the existing literatures has explored the contribution of poverty to the psychiatric disability among Chinese population. Using a nationally representative data, this paper aims to investigate the association between poverty and psychiatric disability in Chinese population aged 15–64 years. We used the second China National Sample Survey on Disability, comprising 1.8 million people aged 15–64 years. Identification and classification for psychiatric disability was based on consensus manuals. We used standard weighting procedures to construct sample weights considering the multistage stratified cluster sampling survey scheme. Population weighted numbers, weighted proportions, and the adjusted Odd Ratios (OR) were calculated. For people with psychiatric disability aged 15–64 years, more than 4 million were below the poverty level in China. After controlling for other demographic variables, poverty was found to be significantly associated with psychiatric disability (OR ¼ 2.25, 95% Confidence Interval (CI) 2.15–2.35). Given China is undergoing rapid social-economic transition and psychiatric diseases become a leading burden to the individuals, community, and health care systems, poverty reduction programs are warranted to prevent psychiatric disability and/or improve the lives for persons with psychiatric disability. & 2012 Elsevier Ireland Ltd. All rights reserved.
Keywords: Poverty Psychiatric disability Chinese population
1. Introduction Poverty may be positively correlated with disability (Elwan, 1999; Wittenburg and Favreault, 2003; Yeo and Moore, 2003; US Census Bureau, 2004; Hoogeveen, 2005). In the United States (US), approximately 12% of disability-free persons were living below the poverty level, whereas poverty was over-presented among disabled population, i.e., 14% of those mildly disabled and 24% of those severely disabled were living below poverty level (US Census Bureau, 2004). In developing countries, approximately 10% of the overall population were disabled and about 20% of the people living below poverty level were disabled (Braithwaite and Mont, 2009). In China, the most populous country in the world, there were about 25 million disabled persons living below the poverty level in 1998 (China Disabled Persons’ Federation, 1998). Poverty related indicators such as inadequate income to purchase basic life necessities, malnutrition, lack of health care access, more risky physical working environment, and residing in polluted environment may contribute to elevated risk of disability (Elwan, 1999). On the other hand, disability may increase the n Correspondence to: Institute of Population Research, Peking University & WHO Collaborating Center for Reproductive Health and Population Science, Beijing, China. Tel.: þ 86 10 62759185; fax: þ 86 10 62751976. E-mail address: [email protected] (X. Zheng).
0165-1781/$ - see front matter & 2012 Elsevier Ireland Ltd. All rights reserved. http://dx.doi.org/10.1016/j.psychres.2012.05.026
exposure to negative living stress, social deprivation, and insufficient treatment of illness, thus result in poverty (Elwan, 1999; Druss et al., 2000). However, this poverty–disability circle has been largely overlooked in the population health agenda especially in developing countries. In China, psychiatric disability accounts for approximately 9% of all disabilities (Zheng et al., 2011). The World Health Organization also indicated that psychiatric diseases had become one of the most important causes of disease burden in China, which would account for one fifth of the total disease burden by 2020 (Murray and Lopez, 1996; Phillips, 2004). Given China is undergoing rapid social and economical transitions, there is a need to describe the role of poverty in psychiatric disability so as to inform future prevention and rehabilitation strategies. In this study, using the nationally representative data from the second China National Sample Survey on Disability conducted in 2006 (Zheng et al., 2011), we aimed to provide a social-demographic snapshot for persons with psychiatric disability and investigate the association between poverty and psychiatric disability in Chinese population aged 15–64 years. We hypothesized that poverty was correlated with psychiatric disability in Chinese population. The findings may increase understanding of the role of poverty in relation with psychiatric disability and facilitate initiatives to improve strategy and policy making to combat psychiatric disability.
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N. Li et al. / Psychiatry Research 200 (2012) 917–920
2. Method
3. Results
2.1. Study population and sampling
3.1. Study population characteristics
This study was derived from a national representative population-based data of the second China National Sample Survey on Disability conducted in 2006. This national survey aimed to describe the prevalence and causes of disability, and to explore the characteristics of people with disabilities in China, which cover all provincial administrative areas in mainland China excluding Hong Kong, Macau, and Taiwan. Multistage stratified and clustering sampling scheme was used in the survey and sampling was conducted with probability proportional to cluster size. Within each stratum, a four-stage sampling strategy was followed involving four natural administrative units (i.e. county, town, village, and community). A total of 2.5 million persons were sampled from randomly selected 5964 communities. Details of the survey protocol and sampling procedures were described elsewhere (Office of the Second China National Sample Survey on Disability, 2007; Zheng et al., 2011). The current study population comprised survey respondents aged 15–64 years.
The study population comprises a weighted estimate of 6.7 million persons aged 15–64 years suffering with psychiatric disability. Less than half (41.0%) of those without disability were below the poverty level, compared with 64.3% of those with psychiatric disability were below the poverty level (Table 1).
2.2. Interviewers and interviewing procedures More than 20,000 interviewers, 6,000 doctors of various specialties, as well as 50,000 survey assistants participated in this survey. Every family member of the selected households was interviewed. For subjects aged 7 years or above, a screen scale of disabilities was conducted by interviewers, and those suspected to be disabled were then examined and diagnosed by doctors. Social-demographic information of the subjects, such as gender, age, residence location, education level, marital status, family annual income, and family size were collected. During the survey, medical and rehabilitation suggestions were provided to those diagnosed as disabled. This study was proved by the State Council of China and informed consents were obtained from the participants or their next of kin.
3.2. Psychiatric disability among people aged 15–64 years Schizophrenia, schizotypal and delusional disorders accounted for 58.9% (weighted n ¼3.9 million) of all the psychiatric disability, followed by organic mental disorders (weighted n ¼0.9 million, weighted proportion¼13.7%), and epilepsy (weighted n¼0.5 million, weighted proportion¼7.5%) (Fig. 1). People having extremely severe psychiatric disability accounted for 27% of all the psychiatric disabled persons, whereas people having mild psychiatric disability accounted for 43% (Fig. 2). 3.3. Association between poverty and psychiatric disability After controlling for age, gender, residence location, marital status, and education level, poverty was found to be significantly associated with psychiatric disability (OR ¼2.25, 95% CI 2.15– 2.35) (Table 2).
4. Discussion 2.3. Identification of people with psychiatric disability During the survey, psychiatrists used the International Statistical Classification of Diseases 10th Revision (ICD-10) to confirm diagnosis of mental disorders (WHO, 1993), and used WHO-DAS II as the grading tool to assess the severity of psychiatric disability, classified as mild, moderate, severe, or extremely severe, among those psychiatrically disabled persons (WHO, 1999). In this study, psychiatric disability refers to having mental disorders lasting more than one year, which manifested in cognitive, affective, and behavior disorders, and limited and restricted the patients’ daily life and social function (WHO, 2001). The use of screening methods, diagnostic tools, and classification and grading standard on psychiatric disability were validated in pilot studies (Office of the Second China National Sample Survey on Disability, 2007; Zhang, 2010a).
2.4. Study variable definition We define poverty for persons with an annual family income per capita lower than 50% of the provincial average level were considered to be under poverty level, employing the provincial income data from the 2006 China Statistical Year Book (National Bureau of Statistics of China, 2007). We defined the status of psychiatric disability as binary, i.e., yes or no; poverty as below poverty level or not; age group as 15–19, 20–24, 25–29, 30–34, 35–39, 40–44, 45–49, 50–54, 55–59, or 60–64; marital status as married, unmarried, or divorced/widowed; education level as illiterate, elementary school, junior high school, or senior high school and above.
2.5. Data analysis We used standard weighting procedures calculating the inverse probability of inclusion for individual survey respondent in the multistage sampling frame to construct sample weights taking into account the complex survey sample design (Lohr, 1999). Population weighted numbers and weighted proportions were calculated where appropriate. Multivariable logistic regression model was used to calculate the adjusted Odd Ratios (OR) and 95% Confidence Interval (CI). Taylor series linearization method was used to estimate variance and corresponding 95% Confidence Interval (CI) (Korn and Graubard, 1999). The procedures SURVEYFREQ and SURVEYLOGISTIC of the SAS 9.1 package were used to perform all the data analyses (SAS Institute Inc., 2002). We set p-value less than 0.05 as statistically significant.
Consistent with the other studies (Elwan, 1999; Hitchen, 2006; Lustig and Strauser, 2007; Lund et al., 2010), this study indicates that poverty was positively correlated with psychiatric disability Table 1 Weighted numbers in thousand (n) and weighted proportions (%) by different characteristics of Chinese population aged 15–64 years. Total (unweighted)
Non-poverty (n, %)
Poverty (n, %)
Age group 15–19 20–24 25–29 30–34 35–39 40–44 45–49 50–54 55–59 60–64
209 148 157 206 239 228 171 192 142 104
Gender Male Female
903 893
272,881 (50.6) 193,683 (50.0) 266,914 (49.5) 193,899 (50.0)
Residence location Urban Rural
628 1167
120,765 (22.4) 176,785 (45.6) 419,031 (77.6) 210,797 (54.4)
Marital status Married Unmarried Divorced or Widowed
361 1370 65
419,240 (77.7) 290,009 (74.8) 104,577 (19.4) 81,125 (20.9) 15,978 (3.0) 16,448 (4.2)
Education level Illiterate Elementary school Junior high school Senior high school and above
176 477 716 427
61,923 44,783 47,642 59,975 70,044 70,229 53,091 61,544 42,185 28,379
46,319 142,602 218,843 132,032
(11.5) (8.3) (8.8) (11.1) (13.0) (13.0) (9.8) (11.4) (7.8) (5.3)
48,391 29,759 32,309 46,209 54,604 47,726 33,367 37,770 31,627 25,820
(12.5) (7.7) (8.3) (11.9) (14.1) (12.3) (8.6) (9.7) (8.2) (6.7)
(8.6) 45,008 (11.6) (26.4) 111,986 (28.9) (40.5) 159,435 (41.1) (24.5) 71,153 (18.4)
N. Li et al. / Psychiatry Research 200 (2012) 917–920
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Fig. 1. Distribution of people with psychiatric disability by different causes.
Extremely severe (1.82, 27%)
Mild (2.86, 43%)
Severe (0.92, 14%)
Moderate (1.08, 16%)
Fig. 2. Distribution of people with psychiatric disability by different severity (weighted number in millions and weighted proportion (%) are presented).
in China’s setting. Filling the existing knowledge gap in the Chinese literatures, this is the first study demonstrating the association between poverty and psychiatric disability in Chinese population aged 15–64 years. Although some mental health impairments may not be identifiable, the use of standardized quality control measures, standardized diagnostic tools, and a nationally representative data with substantial sample size and standardized quality control schemes provided a somewhat robust estimate of the association between poverty and psychiatric disability. Poverty is one of the key social-demographic correlates that affect people’s health, which positively links to other correlates such as education and employment (Elwan, 1999; Lustig and Strauser, 2007). It is not surprising to identify that poverty elevates the risk of psychiatric disability after controlling for the other social-demographic factors. Existing programs in developed countries demonstrate their success in combating the adverse role of poverty in psychiatric disability (Hitchen, 2006; Atkins et al., 2006; Kling et al., 2007). Whether or not translating these programs to a China’s setting could lead to success remains unknown. Nevertheless, the study findings call for developing strategies or programs to combat poverty to prevent and control psychiatric disability in China. Compared with the reported number of psychiatrically disabled persons living below poverty level in 1998 (China Disabled Persons’ Federation, 1998), the proportion as well as the absolute number of people with disabilities below poverty level had increased substantially from 25 to 388 million. This increase
might be due to the change of disability definition and the difference in criteria for poverty. For persons with psychiatric disability aged 15–64 years, more than 4 million were below the poverty level in 2006. Considering the under-development status of mental health service system (Hu et al., 2006; Park et al., 2005), as well as the lack of sound social support and financial support systems for disabled people (Qi et al., 2008; Zheng, 2008; Zhang, 2010b), more efforts and countermeasures should be taken to improve the life of the psychiatric disabled people living below poverty level in China. Poverty and disability were mutually causal to each other, i.e., living in poverty could elevate the risk of disability whereas disability could elevate the risk of living in poverty (Elwan, 1999). However, this cross-sectional study did not reveal the causal relationship between poverty and psychiatric disability. It is also possible that psychiatric disability may result in poverty, which could be attributed to stigma, unemployment, and job discrimination (Druss et al., 2000). To overcome this major limitation, further cohort studies employing temporal information about age at onset of disability and income prior to the onset of disability may confirm the causation pathway for poverty and psychiatric disability. Nevertheless, no matter what causation scenario is the case as to the association between poverty and psychiatric disability, the problem of poverty in psychiatrically disabled persons is worth close attention and immediate action. Strategies on reducing poverty and improving the life of people with psychiatric disability should be developed.
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Table 2 Adjusted Odds Ratio (OR) and its 95% Confidence Interval (CI) for psychiatric disability among Chinese people aged 15–64 years. OR (95% CI)
P o 0.001
Poverty No Yes
Referent 2.25 (2.15–2.35)
Age group 15–19 20–24 25–29 30–34 35–39 40–44 45–49 50–54 55–59 60–64
Referent 3.15 (2.77–3.58) 9.45 (8.32–10.74) 15.49 (13.55–17.71) 18.64 (16.29–21.32) 21.43 (18.72–24.53) 19.53 (16.91–22.55) 17.21 (14.88–19.91) 16.56 (14.25–19.23) 13.00 (11.09–15.23)
Gender Male Female
Referent 1.28 (1.22–1.34)
o 0.001
o 0.001
o 0.001
Residence location Urban Rural 0.5 Marital status Married Unmarried Divorced or Widowed
Referent 9.12 (8.56–9.70) 3.12 (2.91–3.34)
Education level Illiterate Elementary school Junior high school Senior high school and above
Referent 0.47 (0.45–0.50) 0.31 (0.28–0.33) 0.25 (0.22–0.27)
Referent 1.31 (1.23–1.39) o 0.001
o 0.001
Given China is undergoing rapid social-economic transition and psychiatric diseases become a leading disability burden to the individuals, communities, and health care systems, poverty reduction programs are warranted to prevent psychiatric disability and/or improve the lives for persons with psychiatric disability.
Acknowledgments This study was supported by the State Key Development Program of Basic Research of China973 (no. 2007CB511901), Yang Zi Program of MOE, State Key Funds of Social Science Project (Research on Disability Prevention Measurement in China, no. 09&ZD072). WD is supported by an NHMRC exchange program. References Atkins, M.S., Frazier, S.L., Birman, D., Adil, J.A., Jackson, M., Graczyk, P.A., Talbott, E., Farmer, A.D., Bell, C.C., McKay, M.M., 2006. School-based mental health
services for children living in high poverty urban communities. Administration and Policy in Mental Health 33 (2), 146–159. Braithwaite, J., Mont, D., 2009. Disability and poverty: a survey of World Bank Poverty Assessments and implications. European Journal of Disability Research 3, 219–232. China Disabled Persons’ Federation, 1998. Report on Families with Disabled Persons below Poverty Level in 1998. /http://www.cdpf.org.cn/old/zulian/ zl0006.htmS. Druss, B.G., Marcus, S.C., Rosenheck, R.A., Olfson, M., Tanielian, T., Pincus, H.A., 2000. Understanding disability in mental and general medical conditions. American Journal of Psychiatry 157, 1485–1491. Elwan, A., 1999. Poverty and Disability: A Survey of the Literature. Social Protection Discussion Paper Series no. 9932. The World Bank. Hitchen, L., 2006. Address poverty to reduce mental health problems among children, says BMA. British Medical Journal 332 (7556), 1471. Hoogeveen, J., 2005. Measuring welfare for small but vulnerable groups: poverty and disability in Uganda. Journal of African Economies 14, 603–631. Hu, J., Higgins, J., Higgins, L.T., 2006. Development and limits to development of mental health services in China. Criminal Behaviour and Mental Health 16, 69–76. Kling, J., Liebman, J., Katz, L., 2007. Experimental analysis of neighborhood effects. Econometrica 75 (1), 83–119. Korn, E., Graubard, B., 1999. Analysis of Health Surveys. Wiley, New York. Lohr, S., 1999. Sampling: Design and Analysis. Duxbury Press, Pacific Grove. Lund, C., Breen, A., Flisher, A.J., Kakuma, R., Corriqall, J., Joska, J.A., Swartz, L., Patel, V., 2010. Poverty and common mental disorders in low and middle income countries: a systematic review. Social Science & Medicine 71, 517–528. Lustig, D.C., Strauser, D.R., 2007. Causal relationships between poverty and disability. Rehabilitation Counseling Bulletin 4, 194–202. Murray, C.J.L., Lopez, A.D., 1996. The Global Burden of Disease: A Comprehensive Assessment of Mortality and Disability from Diseases, Injuries, and Risk Factors in 1990 and Projected to 2020. Harvard University Press, Cambridge, MA. National Bureau of Statistics of China, 2007. China Statistical Year Book 2006. China Statistics Press, Beijing, China. Office of the Second China National Sample Survey on Disability, 2007. Documentation of the Second China National Sample Survey on Disability. China Statistics Press, Beijing, China. Park, L., Xiao, Z., Worth, J., Park, J.M., 2005. Mental health care in China: recent changes and future challenges. Harvard Health Policy Review 2, 35–45. Phillips, M.R., 2004. Mental health in China: challenge and choice in the 21st century. Chinese Journal of Nervous and Mental Diseases 30, 1–10. (in Chinese). Qi, X., Li, C., Chen, X., Guo, Y., 2008. Report on the social security for the disabled persons in Beijing. Population and Development 3, 1–10. (in Chinese). SAS Institute Inc., 2002. Statistical Analysis Software (SAS) Version 9.1. SAS Institute Inc, Cary, NC. US Census Bureau, 2004. Survey of Income and Program Participation 1991. /http://www.census.gov/population/pop-profile/disabilityS. WHO, 1993. The ICD-10 Classification of Mental and Behavioral Disorders: Diagnostic Criteria for Research. World Health Organization, Geneva. WHO, 1999. The World Health Organization Disability Assessment Schedule Phase II Field Trial Instrument. World Health Organization, Geneva, Switzerland. WHO, 2001. International Classification of Functioning, Disability, and Health (ICF). World Health Organization, Geneva. Wittenburg, D., Favreault, M., 2003. Safety Net or Tangled Web? An Overview of Programs and Services for Adults with Disabilities. Urban Institute, Washington, DC. Yeo, R., Moore, K., 2003. Including disabled people in poverty reduction work: nothing about us, without us. World Development 31, 571–590. Zhang, J., 2010a. Study of Disability Survey Method. Dissertation, Peking University (in Chinese). Zhang, J., 2010b. A Study on the Social Support System for People with Disabilities in Urban Area—Taking Xi’an City as an Example. Dissertation, Northwest University (in Chinese). Zheng, G., 2008. The social security for people with disabilities in China: current situation and development strategy. Journal of Renmin University of China 10, 1–8. (in Chinese). Zheng, X., Chen, G., Song, X., Liu, J., Yan, L., Du, W., Pang, L., Zhang, L., Wu, J., Zhang, B., Zhang, J., 2011. Twenty-year trends in the prevalence of disability in China. Bulletin of the World Health Organization 89, 788–797.
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Psychiatry Research journal homepage: www.elsevier.com/locate/psychres
Association between poverty and psychiatric disability among Chinese population aged 15–64 years Ning Li, Lihua Pang, Wei Du, Gong Chen, Xiaoying Zheng n Institute of Population Research, No. 5, Yiheyuan Road, Haidian District, Peking University, Beijing, China
a r t i c l e i n f o
abstract
Article history: Received 11 September 2011 Received in revised form 14 May 2012 Accepted 24 May 2012
Psychiatric disability is an important public health problem in China, and poverty may be positively correlated with disability. Little study in the existing literatures has explored the contribution of poverty to the psychiatric disability among Chinese population. Using a nationally representative data, this paper aims to investigate the association between poverty and psychiatric disability in Chinese population aged 15–64 years. We used the second China National Sample Survey on Disability, comprising 1.8 million people aged 15–64 years. Identification and classification for psychiatric disability was based on consensus manuals. We used standard weighting procedures to construct sample weights considering the multistage stratified cluster sampling survey scheme. Population weighted numbers, weighted proportions, and the adjusted Odd Ratios (OR) were calculated. For people with psychiatric disability aged 15–64 years, more than 4 million were below the poverty level in China. After controlling for other demographic variables, poverty was found to be significantly associated with psychiatric disability (OR ¼ 2.25, 95% Confidence Interval (CI) 2.15–2.35). Given China is undergoing rapid social-economic transition and psychiatric diseases become a leading burden to the individuals, community, and health care systems, poverty reduction programs are warranted to prevent psychiatric disability and/or improve the lives for persons with psychiatric disability. & 2012 Elsevier Ireland Ltd. All rights reserved.
Keywords: Poverty Psychiatric disability Chinese population
1. Introduction Poverty may be positively correlated with disability (Elwan, 1999; Wittenburg and Favreault, 2003; Yeo and Moore, 2003; US Census Bureau, 2004; Hoogeveen, 2005). In the United States (US), approximately 12% of disability-free persons were living below the poverty level, whereas poverty was over-presented among disabled population, i.e., 14% of those mildly disabled and 24% of those severely disabled were living below poverty level (US Census Bureau, 2004). In developing countries, approximately 10% of the overall population were disabled and about 20% of the people living below poverty level were disabled (Braithwaite and Mont, 2009). In China, the most populous country in the world, there were about 25 million disabled persons living below the poverty level in 1998 (China Disabled Persons’ Federation, 1998). Poverty related indicators such as inadequate income to purchase basic life necessities, malnutrition, lack of health care access, more risky physical working environment, and residing in polluted environment may contribute to elevated risk of disability (Elwan, 1999). On the other hand, disability may increase the n Correspondence to: Institute of Population Research, Peking University & WHO Collaborating Center for Reproductive Health and Population Science, Beijing, China. Tel.: þ 86 10 62759185; fax: þ 86 10 62751976. E-mail address: [email protected] (X. Zheng).
0165-1781/$ - see front matter & 2012 Elsevier Ireland Ltd. All rights reserved. http://dx.doi.org/10.1016/j.psychres.2012.05.026
exposure to negative living stress, social deprivation, and insufficient treatment of illness, thus result in poverty (Elwan, 1999; Druss et al., 2000). However, this poverty–disability circle has been largely overlooked in the population health agenda especially in developing countries. In China, psychiatric disability accounts for approximately 9% of all disabilities (Zheng et al., 2011). The World Health Organization also indicated that psychiatric diseases had become one of the most important causes of disease burden in China, which would account for one fifth of the total disease burden by 2020 (Murray and Lopez, 1996; Phillips, 2004). Given China is undergoing rapid social and economical transitions, there is a need to describe the role of poverty in psychiatric disability so as to inform future prevention and rehabilitation strategies. In this study, using the nationally representative data from the second China National Sample Survey on Disability conducted in 2006 (Zheng et al., 2011), we aimed to provide a social-demographic snapshot for persons with psychiatric disability and investigate the association between poverty and psychiatric disability in Chinese population aged 15–64 years. We hypothesized that poverty was correlated with psychiatric disability in Chinese population. The findings may increase understanding of the role of poverty in relation with psychiatric disability and facilitate initiatives to improve strategy and policy making to combat psychiatric disability.
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N. Li et al. / Psychiatry Research 200 (2012) 917–920
2. Method
3. Results
2.1. Study population and sampling
3.1. Study population characteristics
This study was derived from a national representative population-based data of the second China National Sample Survey on Disability conducted in 2006. This national survey aimed to describe the prevalence and causes of disability, and to explore the characteristics of people with disabilities in China, which cover all provincial administrative areas in mainland China excluding Hong Kong, Macau, and Taiwan. Multistage stratified and clustering sampling scheme was used in the survey and sampling was conducted with probability proportional to cluster size. Within each stratum, a four-stage sampling strategy was followed involving four natural administrative units (i.e. county, town, village, and community). A total of 2.5 million persons were sampled from randomly selected 5964 communities. Details of the survey protocol and sampling procedures were described elsewhere (Office of the Second China National Sample Survey on Disability, 2007; Zheng et al., 2011). The current study population comprised survey respondents aged 15–64 years.
The study population comprises a weighted estimate of 6.7 million persons aged 15–64 years suffering with psychiatric disability. Less than half (41.0%) of those without disability were below the poverty level, compared with 64.3% of those with psychiatric disability were below the poverty level (Table 1).
2.2. Interviewers and interviewing procedures More than 20,000 interviewers, 6,000 doctors of various specialties, as well as 50,000 survey assistants participated in this survey. Every family member of the selected households was interviewed. For subjects aged 7 years or above, a screen scale of disabilities was conducted by interviewers, and those suspected to be disabled were then examined and diagnosed by doctors. Social-demographic information of the subjects, such as gender, age, residence location, education level, marital status, family annual income, and family size were collected. During the survey, medical and rehabilitation suggestions were provided to those diagnosed as disabled. This study was proved by the State Council of China and informed consents were obtained from the participants or their next of kin.
3.2. Psychiatric disability among people aged 15–64 years Schizophrenia, schizotypal and delusional disorders accounted for 58.9% (weighted n ¼3.9 million) of all the psychiatric disability, followed by organic mental disorders (weighted n ¼0.9 million, weighted proportion¼13.7%), and epilepsy (weighted n¼0.5 million, weighted proportion¼7.5%) (Fig. 1). People having extremely severe psychiatric disability accounted for 27% of all the psychiatric disabled persons, whereas people having mild psychiatric disability accounted for 43% (Fig. 2). 3.3. Association between poverty and psychiatric disability After controlling for age, gender, residence location, marital status, and education level, poverty was found to be significantly associated with psychiatric disability (OR ¼2.25, 95% CI 2.15– 2.35) (Table 2).
4. Discussion 2.3. Identification of people with psychiatric disability During the survey, psychiatrists used the International Statistical Classification of Diseases 10th Revision (ICD-10) to confirm diagnosis of mental disorders (WHO, 1993), and used WHO-DAS II as the grading tool to assess the severity of psychiatric disability, classified as mild, moderate, severe, or extremely severe, among those psychiatrically disabled persons (WHO, 1999). In this study, psychiatric disability refers to having mental disorders lasting more than one year, which manifested in cognitive, affective, and behavior disorders, and limited and restricted the patients’ daily life and social function (WHO, 2001). The use of screening methods, diagnostic tools, and classification and grading standard on psychiatric disability were validated in pilot studies (Office of the Second China National Sample Survey on Disability, 2007; Zhang, 2010a).
2.4. Study variable definition We define poverty for persons with an annual family income per capita lower than 50% of the provincial average level were considered to be under poverty level, employing the provincial income data from the 2006 China Statistical Year Book (National Bureau of Statistics of China, 2007). We defined the status of psychiatric disability as binary, i.e., yes or no; poverty as below poverty level or not; age group as 15–19, 20–24, 25–29, 30–34, 35–39, 40–44, 45–49, 50–54, 55–59, or 60–64; marital status as married, unmarried, or divorced/widowed; education level as illiterate, elementary school, junior high school, or senior high school and above.
2.5. Data analysis We used standard weighting procedures calculating the inverse probability of inclusion for individual survey respondent in the multistage sampling frame to construct sample weights taking into account the complex survey sample design (Lohr, 1999). Population weighted numbers and weighted proportions were calculated where appropriate. Multivariable logistic regression model was used to calculate the adjusted Odd Ratios (OR) and 95% Confidence Interval (CI). Taylor series linearization method was used to estimate variance and corresponding 95% Confidence Interval (CI) (Korn and Graubard, 1999). The procedures SURVEYFREQ and SURVEYLOGISTIC of the SAS 9.1 package were used to perform all the data analyses (SAS Institute Inc., 2002). We set p-value less than 0.05 as statistically significant.
Consistent with the other studies (Elwan, 1999; Hitchen, 2006; Lustig and Strauser, 2007; Lund et al., 2010), this study indicates that poverty was positively correlated with psychiatric disability Table 1 Weighted numbers in thousand (n) and weighted proportions (%) by different characteristics of Chinese population aged 15–64 years. Total (unweighted)
Non-poverty (n, %)
Poverty (n, %)
Age group 15–19 20–24 25–29 30–34 35–39 40–44 45–49 50–54 55–59 60–64
209 148 157 206 239 228 171 192 142 104
Gender Male Female
903 893
272,881 (50.6) 193,683 (50.0) 266,914 (49.5) 193,899 (50.0)
Residence location Urban Rural
628 1167
120,765 (22.4) 176,785 (45.6) 419,031 (77.6) 210,797 (54.4)
Marital status Married Unmarried Divorced or Widowed
361 1370 65
419,240 (77.7) 290,009 (74.8) 104,577 (19.4) 81,125 (20.9) 15,978 (3.0) 16,448 (4.2)
Education level Illiterate Elementary school Junior high school Senior high school and above
176 477 716 427
61,923 44,783 47,642 59,975 70,044 70,229 53,091 61,544 42,185 28,379
46,319 142,602 218,843 132,032
(11.5) (8.3) (8.8) (11.1) (13.0) (13.0) (9.8) (11.4) (7.8) (5.3)
48,391 29,759 32,309 46,209 54,604 47,726 33,367 37,770 31,627 25,820
(12.5) (7.7) (8.3) (11.9) (14.1) (12.3) (8.6) (9.7) (8.2) (6.7)
(8.6) 45,008 (11.6) (26.4) 111,986 (28.9) (40.5) 159,435 (41.1) (24.5) 71,153 (18.4)
N. Li et al. / Psychiatry Research 200 (2012) 917–920
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Fig. 1. Distribution of people with psychiatric disability by different causes.
Extremely severe (1.82, 27%)
Mild (2.86, 43%)
Severe (0.92, 14%)
Moderate (1.08, 16%)
Fig. 2. Distribution of people with psychiatric disability by different severity (weighted number in millions and weighted proportion (%) are presented).
in China’s setting. Filling the existing knowledge gap in the Chinese literatures, this is the first study demonstrating the association between poverty and psychiatric disability in Chinese population aged 15–64 years. Although some mental health impairments may not be identifiable, the use of standardized quality control measures, standardized diagnostic tools, and a nationally representative data with substantial sample size and standardized quality control schemes provided a somewhat robust estimate of the association between poverty and psychiatric disability. Poverty is one of the key social-demographic correlates that affect people’s health, which positively links to other correlates such as education and employment (Elwan, 1999; Lustig and Strauser, 2007). It is not surprising to identify that poverty elevates the risk of psychiatric disability after controlling for the other social-demographic factors. Existing programs in developed countries demonstrate their success in combating the adverse role of poverty in psychiatric disability (Hitchen, 2006; Atkins et al., 2006; Kling et al., 2007). Whether or not translating these programs to a China’s setting could lead to success remains unknown. Nevertheless, the study findings call for developing strategies or programs to combat poverty to prevent and control psychiatric disability in China. Compared with the reported number of psychiatrically disabled persons living below poverty level in 1998 (China Disabled Persons’ Federation, 1998), the proportion as well as the absolute number of people with disabilities below poverty level had increased substantially from 25 to 388 million. This increase
might be due to the change of disability definition and the difference in criteria for poverty. For persons with psychiatric disability aged 15–64 years, more than 4 million were below the poverty level in 2006. Considering the under-development status of mental health service system (Hu et al., 2006; Park et al., 2005), as well as the lack of sound social support and financial support systems for disabled people (Qi et al., 2008; Zheng, 2008; Zhang, 2010b), more efforts and countermeasures should be taken to improve the life of the psychiatric disabled people living below poverty level in China. Poverty and disability were mutually causal to each other, i.e., living in poverty could elevate the risk of disability whereas disability could elevate the risk of living in poverty (Elwan, 1999). However, this cross-sectional study did not reveal the causal relationship between poverty and psychiatric disability. It is also possible that psychiatric disability may result in poverty, which could be attributed to stigma, unemployment, and job discrimination (Druss et al., 2000). To overcome this major limitation, further cohort studies employing temporal information about age at onset of disability and income prior to the onset of disability may confirm the causation pathway for poverty and psychiatric disability. Nevertheless, no matter what causation scenario is the case as to the association between poverty and psychiatric disability, the problem of poverty in psychiatrically disabled persons is worth close attention and immediate action. Strategies on reducing poverty and improving the life of people with psychiatric disability should be developed.
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N. Li et al. / Psychiatry Research 200 (2012) 917–920
Table 2 Adjusted Odds Ratio (OR) and its 95% Confidence Interval (CI) for psychiatric disability among Chinese people aged 15–64 years. OR (95% CI)
P o 0.001
Poverty No Yes
Referent 2.25 (2.15–2.35)
Age group 15–19 20–24 25–29 30–34 35–39 40–44 45–49 50–54 55–59 60–64
Referent 3.15 (2.77–3.58) 9.45 (8.32–10.74) 15.49 (13.55–17.71) 18.64 (16.29–21.32) 21.43 (18.72–24.53) 19.53 (16.91–22.55) 17.21 (14.88–19.91) 16.56 (14.25–19.23) 13.00 (11.09–15.23)
Gender Male Female
Referent 1.28 (1.22–1.34)
o 0.001
o 0.001
o 0.001
Residence location Urban Rural 0.5 Marital status Married Unmarried Divorced or Widowed
Referent 9.12 (8.56–9.70) 3.12 (2.91–3.34)
Education level Illiterate Elementary school Junior high school Senior high school and above
Referent 0.47 (0.45–0.50) 0.31 (0.28–0.33) 0.25 (0.22–0.27)
Referent 1.31 (1.23–1.39) o 0.001
o 0.001
Given China is undergoing rapid social-economic transition and psychiatric diseases become a leading disability burden to the individuals, communities, and health care systems, poverty reduction programs are warranted to prevent psychiatric disability and/or improve the lives for persons with psychiatric disability.
Acknowledgments This study was supported by the State Key Development Program of Basic Research of China973 (no. 2007CB511901), Yang Zi Program of MOE, State Key Funds of Social Science Project (Research on Disability Prevention Measurement in China, no. 09&ZD072). WD is supported by an NHMRC exchange program. References Atkins, M.S., Frazier, S.L., Birman, D., Adil, J.A., Jackson, M., Graczyk, P.A., Talbott, E., Farmer, A.D., Bell, C.C., McKay, M.M., 2006. School-based mental health
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