551200 research-article2014
APHXXX10.1177/1010539514551200Asia-Pacific Journal of Public HealthWang et al.
Original Article
Rural–Urban Differences in the Prevalence of Chronic Disease in Northeast China
Asia-Pacific Journal of Public Health 1–13 © 2014 APJPH Reprints and permissions: sagepub.com/journalsPermissions.nav DOI: 10.1177/1010539514551200 aph.sagepub.com
Shibin Wang, BSMed1, Changgui Kou, PhD1, Yawen Liu, PhD1, Bo Li, PhD1, Yuchun Tao, PhD1, Carl D’Arcy, PhD2, Jieping Shi, BSMed1, Yanhua Wu, BSMed1, Jianwei Liu, BSMed3, Yingli Zhu, BSMed3, and Yaqin Yu, PhD1
Abstract Rural–urban differences in the prevalence of chronic diseases in the adult population of northeast China are examined. The Jilin Provincial Chronic Disease Survey used personal interviews and physical measures to research the presence of a range of chronic diseases among a large sample of rural and urban provincial residents aged 18 to 79 years (N = 21 435). Logistic regression analyses were used. After adjusting for age and gender, rural residents had higher prevalence of hypertension, chronic ischemic heart disease, cerebrovascular disease, chronic low back pain, arthritis, chronic gastroenteritis/peptic ulcer, chronic cholecystitis/gallstones, and chronic lower respiratory disease. Low education, low income, and smoking increased the risk of chronic diseases in rural areas. Reducing rural–urban differences in chronic disease presents a formidable public health challenge for China. The solution requires focusing attention on issues endemic to rural areas such as poverty, lack of chronic disease knowledge, and the inequality in access to primary care. Keywords chronic disease, health disparity, risk factor, rural, socioeconomic status, Jilin, China
Introduction Demographic aging, rapid unplanned urbanization, and the globalization of unhealthy lifestyles are driving the epidemic of chronic diseases touching every region of the world, particularly developing countries.1 Contrary to popular opinion, available data demonstrate that around 80% of all chronic disease deaths (29 million) occurred in low- and middle-income countries.2 Chronic diseases are caused, to a large extent, by 4 behavioral risk factors: tobacco use, unhealthy diet, insufficient physical activity, and the harmful use of alcohol.3 The effects of these risk factors in
1Jilin
University, Changchun, China of Saskatchewan, Saskatoon, Saskatchewan, Canada 3Jilin Provincial Center for Disease Control and Prevention, Changchun, China 2University
Corresponding Author: Yaqin Yu, Department of Epidemiology and Biostatistics, School of Public Health, Jilin University, 1163 Xinmin Street, Changchun 130021, China. Email: [email protected]
Downloaded from aph.sagepub.com at UNIV OF OKLAHOMA on March 28, 2015
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Asia-Pacific Journal of Public Health
developing countries reflect underlying socioeconomic determinants, such as education, household income, living conditions, and access to quality health care.1,4 China has had an enviable economic growth and development performance for more than 30 years, and the health status of its population has changed radically as well.5 As a developing middle-income country, China has made impressive gains in recent decades to control communicable disease through health interventions such as increased vaccination coverage, improved access to health care, and improved economic living standards. However, the “new” China has to confront chronic noncommunicable diseases as leading causes of ill health, premature mortality, and disability.6,7 Despite the rapid economic transition in China, there are still significant rural– urban differences in socioeconomic status and health status.8,9 These differences are manifested in education, income, living conditions, the availability of medical insurance and the quality of health services.9-11 Previous studies have indicated that the prevalence of chronic diseases in the circulatory system, and endocrine, nutritional, and metabolic diseases were higher among urban residents than rural residents.9,12-14 However, because of large-scale rural-to-urban migration in which young people have moved into cities leaving the elderly behind in rural areas, China’s rural areas are aging more rapidly than its cities.15 Although in the past 10 years, a new health insurance system, the New Cooperative Medical Scheme (NCMS), has been adopted in rural areas, people do not find that the NCMS decreases out-of-pocket expenditure; nor has it been found to increase the utilization of formal medical services or improve health status.16 Therefore, it is important to examine potential rural-urban differences in chronic diseases prevalence more closely, particularly as they relate to the range of established risk factors. In this article, we describe and compare prevalence rates of chronic diseases between rural and urban residents in Jilin Province, which is an intermediately economically developed province located in the central part of northeastern China, with a total population of 27.5 million.17,18 The analyses used data from Jilin Provincial Chronic Disease Survey of 2012, which is the first comprehensive baseline chronic disease survey in this area. Besides the rural–urban variations in the prevalence of chronic diseases, we also examined whether such differences can be explained by inequalities in socioeconomic status and other well-established risk factors. The results provide useful information for policy makers in making informed decisions to reduce the rural– urban health disparity and the effectiveness of health investments.
Methods Setting and Sampling This baseline survey is part of the Project on Present Situation and Change Forecast of Disease Spectrum in Jilin Province of China. The Jilin Provincial Chronic Disease Survey was a face-toface health interview and physical examination survey conducted from June 2012 to August 2012 among individuals aged 18 to 79 years. The survey sample size calculation took into account the estimated prevalence of the different chronic diseases to be surveyed (varying between 0.02 and 0.99), the absolute error (varying between 0.01 and 0.10), a confidence level of 95%, the costs of data collection, physical examinations, and laboratory tests. The final target sample size was established at 25 240, which is about 1‰ of the total adult population in Jilin Province. A multistage stratified cluster sample was used. In the first stage, the province was stratified into 9 regions, which cover all of Jilin Province (Changchun, Jilin [city], Siping, Liaoyuan, Tonghua, Baishan, Songyuan, Baicheng, and Yanbian). The regions are administrative areas that are largely responsible for health care delivery. In the second stage, clusters of 4 districts or counties were randomly selected from each of the 9 regions using probability proportional to size
Downloaded from aph.sagepub.com at UNIV OF OKLAHOMA on March 28, 2015
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Wang et al.
(PPS) sampling. In the third stage, each selected district or county was divided into urban and rural areas as defined by the National Bureau of Statistics of China.17 Subsequently 4 or 5 communities were sampled from both rural and urban strata using PPS. Finally, 1 adult resident was randomly selected from each household of the selected communities. Respondents who were judged to very frail or ill were excluded from completing the survey. The Ethics Committee of Jilin University School of Public Health approved the study (Reference Number: 2012-R-011). All participants gave written informed consent prior to participating in the survey.
Procedures A total of 116 investigators were trained together on uniform survey procedures and divided into 4 teams to interview the participants. All on-site interviews and screenings were done in examination centers at local health stations or community clinics in the participants’ residential area. A detailed structured interview was used to collect information on age, gender, level of education, income class, medical insurance, smoking status, and diagnosed chronic disease history in the past 12 months.
Dependent Measures To determine a person’s chronic disease status, respondents were asked “Have you ever been told by a doctor, nurse or other health professional that you have any chronic disease?” Respondents were shown a table displaying 32 kinds of chronic diseases based on the codes of International Classification of Disease, 10th Revision (ICD-10), see Table 1. All the selected chronic diseases were spoken out by investigators to the respondents in local language (dialect) to help them recall the relevant diagnosis and they were encouraged to ask about these diseases if they were not clear of the diseases. Respondents answered either “yes” or “no.” If the survey participant answered “yes,” then further questions were asked and the response was recorded.
Independent Measures Income was measured at the household level and classified into 5 classes: low income class, lower-middle class, middle class, higher-middle class, high class, according to Jilin Provincial Bureau of Statistics.18 Medical insurance includes Urban Employee Basic Medical Insurance (UEBMI), Urban Resident Basic Medical Insurance (URBMI), New Rural Cooperative Medical Insurance (NRCMI), state free medical service and commercial health insurance. Smoking status was categorized into current smoker, former smoker, and never smoked. Those who reported smoking at least 100 cigarettes in their lifetime and smoked either everyday or some days at the time of the survey were defined as current smoker. Those who reported smoking at least 100 cigarettes in their lifetime and did not smoke at all at the time of the survey were defined as former smokers. Those who reported never having smoked 100 cigarettes were defined as never smoked.19 All participants were also recruited for a physical examination, which was conducted at a field survey site. Height was measured to the nearest 0.1 cm without shoes using an anthropometer. Weight was recorded in light clothing to the nearest 0.1 kg after removal of shoes. Body mass index (BMI) was calculated as weight (kg)/height (m)2 (kg/m2). We categorized adults as not overweight or obesity with BMI
APHXXX10.1177/1010539514551200Asia-Pacific Journal of Public HealthWang et al.
Original Article
Rural–Urban Differences in the Prevalence of Chronic Disease in Northeast China
Asia-Pacific Journal of Public Health 1–13 © 2014 APJPH Reprints and permissions: sagepub.com/journalsPermissions.nav DOI: 10.1177/1010539514551200 aph.sagepub.com
Shibin Wang, BSMed1, Changgui Kou, PhD1, Yawen Liu, PhD1, Bo Li, PhD1, Yuchun Tao, PhD1, Carl D’Arcy, PhD2, Jieping Shi, BSMed1, Yanhua Wu, BSMed1, Jianwei Liu, BSMed3, Yingli Zhu, BSMed3, and Yaqin Yu, PhD1
Abstract Rural–urban differences in the prevalence of chronic diseases in the adult population of northeast China are examined. The Jilin Provincial Chronic Disease Survey used personal interviews and physical measures to research the presence of a range of chronic diseases among a large sample of rural and urban provincial residents aged 18 to 79 years (N = 21 435). Logistic regression analyses were used. After adjusting for age and gender, rural residents had higher prevalence of hypertension, chronic ischemic heart disease, cerebrovascular disease, chronic low back pain, arthritis, chronic gastroenteritis/peptic ulcer, chronic cholecystitis/gallstones, and chronic lower respiratory disease. Low education, low income, and smoking increased the risk of chronic diseases in rural areas. Reducing rural–urban differences in chronic disease presents a formidable public health challenge for China. The solution requires focusing attention on issues endemic to rural areas such as poverty, lack of chronic disease knowledge, and the inequality in access to primary care. Keywords chronic disease, health disparity, risk factor, rural, socioeconomic status, Jilin, China
Introduction Demographic aging, rapid unplanned urbanization, and the globalization of unhealthy lifestyles are driving the epidemic of chronic diseases touching every region of the world, particularly developing countries.1 Contrary to popular opinion, available data demonstrate that around 80% of all chronic disease deaths (29 million) occurred in low- and middle-income countries.2 Chronic diseases are caused, to a large extent, by 4 behavioral risk factors: tobacco use, unhealthy diet, insufficient physical activity, and the harmful use of alcohol.3 The effects of these risk factors in
1Jilin
University, Changchun, China of Saskatchewan, Saskatoon, Saskatchewan, Canada 3Jilin Provincial Center for Disease Control and Prevention, Changchun, China 2University
Corresponding Author: Yaqin Yu, Department of Epidemiology and Biostatistics, School of Public Health, Jilin University, 1163 Xinmin Street, Changchun 130021, China. Email: [email protected]
Downloaded from aph.sagepub.com at UNIV OF OKLAHOMA on March 28, 2015
2
Asia-Pacific Journal of Public Health
developing countries reflect underlying socioeconomic determinants, such as education, household income, living conditions, and access to quality health care.1,4 China has had an enviable economic growth and development performance for more than 30 years, and the health status of its population has changed radically as well.5 As a developing middle-income country, China has made impressive gains in recent decades to control communicable disease through health interventions such as increased vaccination coverage, improved access to health care, and improved economic living standards. However, the “new” China has to confront chronic noncommunicable diseases as leading causes of ill health, premature mortality, and disability.6,7 Despite the rapid economic transition in China, there are still significant rural– urban differences in socioeconomic status and health status.8,9 These differences are manifested in education, income, living conditions, the availability of medical insurance and the quality of health services.9-11 Previous studies have indicated that the prevalence of chronic diseases in the circulatory system, and endocrine, nutritional, and metabolic diseases were higher among urban residents than rural residents.9,12-14 However, because of large-scale rural-to-urban migration in which young people have moved into cities leaving the elderly behind in rural areas, China’s rural areas are aging more rapidly than its cities.15 Although in the past 10 years, a new health insurance system, the New Cooperative Medical Scheme (NCMS), has been adopted in rural areas, people do not find that the NCMS decreases out-of-pocket expenditure; nor has it been found to increase the utilization of formal medical services or improve health status.16 Therefore, it is important to examine potential rural-urban differences in chronic diseases prevalence more closely, particularly as they relate to the range of established risk factors. In this article, we describe and compare prevalence rates of chronic diseases between rural and urban residents in Jilin Province, which is an intermediately economically developed province located in the central part of northeastern China, with a total population of 27.5 million.17,18 The analyses used data from Jilin Provincial Chronic Disease Survey of 2012, which is the first comprehensive baseline chronic disease survey in this area. Besides the rural–urban variations in the prevalence of chronic diseases, we also examined whether such differences can be explained by inequalities in socioeconomic status and other well-established risk factors. The results provide useful information for policy makers in making informed decisions to reduce the rural– urban health disparity and the effectiveness of health investments.
Methods Setting and Sampling This baseline survey is part of the Project on Present Situation and Change Forecast of Disease Spectrum in Jilin Province of China. The Jilin Provincial Chronic Disease Survey was a face-toface health interview and physical examination survey conducted from June 2012 to August 2012 among individuals aged 18 to 79 years. The survey sample size calculation took into account the estimated prevalence of the different chronic diseases to be surveyed (varying between 0.02 and 0.99), the absolute error (varying between 0.01 and 0.10), a confidence level of 95%, the costs of data collection, physical examinations, and laboratory tests. The final target sample size was established at 25 240, which is about 1‰ of the total adult population in Jilin Province. A multistage stratified cluster sample was used. In the first stage, the province was stratified into 9 regions, which cover all of Jilin Province (Changchun, Jilin [city], Siping, Liaoyuan, Tonghua, Baishan, Songyuan, Baicheng, and Yanbian). The regions are administrative areas that are largely responsible for health care delivery. In the second stage, clusters of 4 districts or counties were randomly selected from each of the 9 regions using probability proportional to size
Downloaded from aph.sagepub.com at UNIV OF OKLAHOMA on March 28, 2015
3
Wang et al.
(PPS) sampling. In the third stage, each selected district or county was divided into urban and rural areas as defined by the National Bureau of Statistics of China.17 Subsequently 4 or 5 communities were sampled from both rural and urban strata using PPS. Finally, 1 adult resident was randomly selected from each household of the selected communities. Respondents who were judged to very frail or ill were excluded from completing the survey. The Ethics Committee of Jilin University School of Public Health approved the study (Reference Number: 2012-R-011). All participants gave written informed consent prior to participating in the survey.
Procedures A total of 116 investigators were trained together on uniform survey procedures and divided into 4 teams to interview the participants. All on-site interviews and screenings were done in examination centers at local health stations or community clinics in the participants’ residential area. A detailed structured interview was used to collect information on age, gender, level of education, income class, medical insurance, smoking status, and diagnosed chronic disease history in the past 12 months.
Dependent Measures To determine a person’s chronic disease status, respondents were asked “Have you ever been told by a doctor, nurse or other health professional that you have any chronic disease?” Respondents were shown a table displaying 32 kinds of chronic diseases based on the codes of International Classification of Disease, 10th Revision (ICD-10), see Table 1. All the selected chronic diseases were spoken out by investigators to the respondents in local language (dialect) to help them recall the relevant diagnosis and they were encouraged to ask about these diseases if they were not clear of the diseases. Respondents answered either “yes” or “no.” If the survey participant answered “yes,” then further questions were asked and the response was recorded.
Independent Measures Income was measured at the household level and classified into 5 classes: low income class, lower-middle class, middle class, higher-middle class, high class, according to Jilin Provincial Bureau of Statistics.18 Medical insurance includes Urban Employee Basic Medical Insurance (UEBMI), Urban Resident Basic Medical Insurance (URBMI), New Rural Cooperative Medical Insurance (NRCMI), state free medical service and commercial health insurance. Smoking status was categorized into current smoker, former smoker, and never smoked. Those who reported smoking at least 100 cigarettes in their lifetime and smoked either everyday or some days at the time of the survey were defined as current smoker. Those who reported smoking at least 100 cigarettes in their lifetime and did not smoke at all at the time of the survey were defined as former smokers. Those who reported never having smoked 100 cigarettes were defined as never smoked.19 All participants were also recruited for a physical examination, which was conducted at a field survey site. Height was measured to the nearest 0.1 cm without shoes using an anthropometer. Weight was recorded in light clothing to the nearest 0.1 kg after removal of shoes. Body mass index (BMI) was calculated as weight (kg)/height (m)2 (kg/m2). We categorized adults as not overweight or obesity with BMI
