Disease burden of COPD in China: a systematic review

Figures & data

Table 1 Inclusion and exclusion criteria

Inclusion criteria	Exclusion criteria
• Chinese or English language Full-text available • Studies that consider the disease burden or quality of life of COPD	• Conference abstracts, case reports, letters, comments, editorials, and review papers • Economic evaluation studies on therapies • Epidemiological studies on pathogenesis or etiology • Intervention studies • Clinical studies • Effect studies • Animal or in vitro studies

Table 2 Quality assessment scale

1. Was the objective clear?

2. Was the data source official?

3. Was the study population-based?

4. Was the sampling randomized?

5. Was the study region nationwide?

6. Were the diagnostic criteria clear?

7. Were the results comparatively analyzed?

8. Did outcome indicators include DALY/YLL/YLD?

9. Can the results be externalized?

Notes: All items have two possible answers except number 9: yes (+) and no (−). Item 9 has three possible responses: yes (++), likely (+), and no (−).

Abbreviations: DALY, disability-adjusted living year; YLL, years of life lost; YLD, years lost due to disability.

Table 3 Characteristics of included studies (n=47)

Study	Publication year	Region of study	Data source	Sample size	Sample age (years)	Indicator of disease burden	Language
Yin et al^Citation10	2015	China	Official statistics		>15	Prevalence, mortality, DALY, YLL, YLD	Chinese
Han et al^Citation11	2015	Heilongjiang	Survey	4,478	>40	Prevalence, influencing factors	Chinese
Shi et al^Citation12	2015	Ningbo, Zhejiang	Institutional data	803	>60	Direct cost	Chinese
Huang^Citation13	2015	Beijing	Institutional data	1,638	73.4±9.07	Direct cost	Chinese
Chen and Bian^Citation14	2015	Zhuji, Zhejiang	Survey	82	36–81	QoL	Chinese
Zhu et al^Citation15	2014	Xinjiang	Survey	2,874	>35	Prevalence, influencing factors	Chinese
Cai et al^Citation16	2014	Yunnan Province	Survey	17,158	>18	Prevalence, influencing factors, direct & indirect cost	English
Xu et al^Citation17	2013	Chengdu, Sichuan	Survey	83	54–86	Direct & indirect cost	Chinese
Zhu et al^Citation18	2013	Jinshan, Shanghai	Institutional data			Mortality, YLL	Chinese
An et al^Citation19	2013	Beijing	Survey	97		QoL	Chinese
Fang et al^Citation20	2013	Shanghai	Survey	101	76.15	QoL	Chinese
Jiang^Citation21	2013	Guangzhou, Guangdong	Survey	278	67.6±8.0	QoL	Chinese
Yang et al^Citation22	2013	China	GBD2010			Mortality, DALY, YLL, YLD	English
Qiu^Citation23	2012	Ningxia	Survey	4,626	>40	Prevalence, influencing factors, consultation rate	Chinese
Mao et al^Citation24	2012	Yunnan (rural)	Survey	9,396	≥18	Prevalence, mortality, DALY, direct & indirect cost	Chinese
Li^Citation25	2008	Guangzhou, Guangdong	Survey	102	38–83	QoL	Chinese
He et al^Citation26	2012	Huaian, Jiangsu	Survey	185	≥60	QoL	Chinese
Lou et al^Citation27	2012	Xuzhou, Jiangsu	Survey	5,900	40–75	Influencing factors, YLL, QoL, direct & indirect cost	English
Lou et al^Citation28	2012	Xuzhou, Jiangsu	Survey	8,217	36–84	Consultation rate, YLL, direct & indirect cost	English
Xu et al^Citation29	2011	China	Survey	1,859	>18	Prevalence, direct & indirect cost	Chinese
Liu et al^Citation30	2011	Meizhou, Guangdong	Survey	134	58–85	QoL	Chinese
Wang et al^Citation31	2011	China	Official statistics		≥40	Prevalence, mortality	English
Fletcher et al^Citation32	2011	Brazil, China, Germany, Turkey, UK, US	Survey	2,426	45–67	QoL, direct & indirect cost	English
Yin et al^Citation33	2011	China	Official statistics	49,363	15–69	Prevalence, influencing factors	English
Guo^Citation34	2010	Guangzhou, Guangdong	Institutional data	669		Direct & indirect cost	Chinese
Lou et al^Citation35	2010	Xuzhou, Jiangsu	Survey	383	34–84	YLL, direct & indirect cost	Chinese
Lu and Li^Citation36	2010	Beijing	Survey	61		QoL	Chinese
Zhou et al^Citation37	2009	China (rural)	Survey	11,290	≥40	Prevalence, influencing factors, consultation rate, QoL	Chinese
Zhou et al^Citation38	2009	China	Survey	20,245	≥40	QoL	Chinese
Chen^Citation39	2009	Shanghai	Institutional data	83	>40	Direct cost	Chinese
An et al^Citation40	2009	Xuzhou, Jiangsu	Survey	383	62	Direct cost	Chinese
He et al^Citation41	2009	China	Survey	723	67±10	QoL, direct & indirect cost	Chinese
Zhu and Cai^Citation42	2009	Beijing	Institutional data	416		Direct cost	Chinese
Hosgood et al^Citation43	2009	Xuan Wei, Yunnan	Survey	160		Influencing factors	English
Jiang et al^Citation44	2008	Hubei	Survey	1,883	>40	Prevalence, consultation rate	Chinese
Cai et al^Citation45	2008	Kunming, Yunnan (Suburban)	Official statistics	335,622	>0	Influencing factors, mortality, YLL	English
Shen et al^Citation46	2008	Xuan Wei, Yunnan	Survey	178		Influencing factors	English
Zhang^Citation47	2007	Shandong	Survey			Direct & indirect cost	Chinese
Jiang et al^Citation48	2007	Hubei	Survey	1,883	>40	Prevalence, influencing factors	Chinese
Zhang et al^Citation49	2007	Chengdu, Sichuan	Survey	446		Direct cost	Chinese
Zhang et al^Citation50	2007	Chengdu, Sichuan	Survey	446	38–94	Consultation rate	Chinese
Xu et al^Citation51	2007	Nanjing	Survey	29,319	≥35	Prevalence, influencing factors	English
Liu et al^Citation52	2007	Guangdong	Survey	3,286	≥40	Prevalence, influencing factors	English
Zhong et al^Citation53	2007	China	Survey	20,245	40–99	Prevalence, influencing factors	English
Yang et al^Citation54	2006	Beijing	Survey	110	68–90	QoL	Chinese
Cai and Chongsuvivatwong^Citation55	2006	Kunming, Yunnan	Official statistics	894,253	>0	Mortality, YLL	English
Ren et al^Citation56	2002	Chengdu, Sichuan	Survey	205		Consultation rate, direct cost	Chinese

Abbreviations: DALY, disability-adjusted living years; YLL, years of life lost; YLD, years lost due to disability; QoL, quality of life.

Figure 1 The process and results of literature screening.

Table 4 Prevalence of COPD in China

Publication year	Study region	Sample size	Age (years)	Prevalence (%)
				Overall	Female	Male	Urban	Rural
2015	China^Citation10		>15	3.90
2015	Heilongjiang^Citation11	4,478	≥40	7.30	6.50	8.60	6.00	8.80
2014	Xinjiang^Citation15	2,874	≥35					7.50
2014	Yunnan^Citation16	17,158	>18	1.20	1.00	1.40
2012	Ningxia^Citation23	4,626	≥40	8.87	5.35	13.01	7.97	9.78
2012	Yunnan^Citation24	9,396	≥18					1.41
2011	China^Citation29	1,859	≥18				1.92
2011	China^Citation33	49,363	15–69	2.20	2.40	3.40	2.50	3.10
2009	China^Citation37	11,290	≥40					8.80
2007	Hubei^Citation48	1,883	≥40					9.88
2007	Nanjing^Citation51	29,319	≥35	5.90
2007	Guangdong^Citation52	3,286	>40	9.40
2007	China^Citation53	20,245	40–99	8.20	5.10	12.40	7.80	8.80

Figure 2 Consultation rate of COPD in China.

Note: *Diagnostic rate is defined by the number of patients who have been diagnosed with COPD in the past divided by the number of subjects recognized as COPD cases through epidemiology research.

Figure 3 Risk factors of COPD in China.

Table 5 Total disease cost of COPD in China*

Publication year	Study region	Sample size	Direct cost (per capita per year, USD)	Direct medical cost (per capita per year, USD)	Direct non-medical cost (per capita per year, USD)	Indirect cost (per capita per year, USD)	Total disease cost (per capita per year, USD)
2015	Ningbo^Citation12	803					685
2013	Chengdu^Citation17	83	1,930			396
2012	Rural Yunnan^Citation24	9,396	884			20
2011	China^Citation29	1,859	726			306	1,033
2010	Xuzhou^Citation28	383		298
2009	Shanghai^Citation39	83		1,323
2009	China^Citation41	723		3,565	477
2007	Shandong^Citation47	150		358	136	783	1,277
2007	Chengdu^Citation49	446	499
2002	Chengdu^Citation56	205		729
2014	Yunnan^Citation16	17,158		1,657	109	22	1,787
2011	Shanghai^Citation32	398		72		77

Notes:

* All Chinese currency in the tables of this section are adjusted to comparable prices to 2013, according to the Residence Consumption Index (http://data.stats.gov.cn/easyquery.htm?cnC01) and converted to USD according to the exchange rate in 2013 (6.1932 RMB=1 USD).

Table 6 Outpatient and hospitalization expenditure of COPD in China

Publication year	Study region	Sample size	Outpatient expenditure (per capita per year) (USD)	Hospitalization expenses (per capita per year) (USD)	Features
2015	Beijing^Citation13	1,638		4,220	Hospital based
2010	Guangzhou^Citation34	669		5,611	Hospital based
2009	Beijing^Citation42	416		20,295	Hospital based
2002	Chengdu^Citation56	205	202	338	Community based
2014	Rural Yunnan^Citation16	17,158	74	1,332	Community based

Figure 4 Major scales used for QoL assessment of COPD patients.

Abbreviations: SGRQ, Saint George Respiratory Questionnaire; AQ20, Airways Questionnaire 20; SF-12, 12-item short-form health survey questionnaire; MCMQ, Medical Coping Modes Questionnaire; CAT, COPD Assessment Test; SF-36, 36-item Short Form Survey Instrument; EQ-5D, EuroQol Five-Dimensional Questionnaire.

Table S1 Quality assessment results of included studies

No	Article title	Quality scale
1	Changing pattern of premature mortality burden over 6 years of rapid growth of the economy in suburban south-west China: 1998–2003	B
2	Rural-urban differentials of premature mortality burden in south-west China	B
3	Rapid health transition in China, 1990–2010: findings from the Global Burden of Disease study 2010	A
4	NSFC health research funding and burden of disease in China	B
5	Toward a healthy and harmonious life in China: stemming the rising tide of non-communicable diseases	B
6	Vulnerability of patients with chronic obstructive pulmonary disease according to gender in China	B
7	Vulnerability, beliefs, treatments and economic burden of chronic obstructive pulmonary disease in rural areas in China: a cross-sectional study	B
8	The economic burden of smoking and secondhand smoke exposure in rural South-West China	B
9	COPD uncovered: an international survey on the impact of chronic obstructive pulmonary disease [COPD] on a working age population	B
10	Better understanding the influence of cigarette smoking and indoor air pollution on chronic obstructive pulmonary disease: a case-control study in Mainland China	A
11	Biomass fuels are the probable risk factor for chronic obstructive pulmonary disease in rural South China	A
12	A report of cytokine polymorphisms and COPD risk in Xuan Wei, China	B
13	PTEN identified as important risk factor of chronic obstructive pulmonary disease	B
14	Effects of smoking and solid-fuel use on COPD, lung cancer, and tuberculosis in China: a time-based, multiple risk factor, modelling study	A
15	Prevalence of chronic obstructive pulmonary disease in Ningxia Province of China (in Chinese)	B
16	The economic burden of chronic obstructive pulmonary disease (COPD) in Shanghai and the feasibility of 3D reconstruction using low-dose CT scan in diagnosis and classification of COPD (in Chinese)	B
17	The study of the economic burden on Chinese rural COPD patients (in Chinese)	B
18	A study on economic burden for hospitalized patients with COPD (in Chinese)	B
19	The risk factors of chronic obstructive pulmonary disease in Heilongjiang province (in Chinese)	B
20	Study on the prevalence rate and risk factors of chronic obstructive pulmonary disease in rural community population in Hubei province (in Chinese)	B
21	Correlation study of body mass index with morbidity rate of chronic obstructive pulmonary disease in parts of Xinjiang (in Chinese)	B
22	Analysis on status of chronic obstructive pulmonary disease in rural population (in Chinese)	B
23	Analysis on economic burden of COPD patients in Tongshan County (in Chinese)	B
24	Direct economic burden of 803 patients with chronic obstructive pulmonary disease and influencing factors in Ningbo (in Chinese)	B
25	The disease burden of chronic obstructive pulmonary disease among people aged over 15 years in 1990 and 2010 in China (in Chinese)	A
26	Analysis on direct economic burden of hospitalized patients with COPD and its influencing factors in a three-level hospital in Beijing (in Chinese)	B
27	Analysis on direct economic burden of community COPD patients and its influence factors in Chengdu (in Chinese)	B
28	Research on direct economic burden of chronic obstructive pulmonary disease in community of Xuzhou City (in Chinese)	B
29	Current status of prevention and management of chronic obstructive pulmonary disease in rural area in China (in Chinese)	A
30	Impact of chronic obstructive pulmonary disease on quality of life and economic burden in Chinese urban areas (in Chinese)	B
31	Costs of the last hospitalization for patients with acute exacerbation of chronic obstructive pulmonary disease and patients with lung cancer (in Chinese)	B
32	The economic burden of the COPD and its factor analysis (in Chinese)	B
33	Analysis of prevalence and economic burden of chronic obstructive pulmonary disease in rural residents of Yunnan Province (in Chinese)	B
34	Economic burden and influence factors of chronic obstructive pulmonary disease patients in Chenghua District (in Chinese)	B
35	Mortality and the trend of YPLL of COPD in Jinshan District of Shanghai City from 1985–2011 (in Chinese)	B
36	Factors influencing the use of health care services from patients with COPD in Chengdu (in Chinese)	B
37	Study on the costs of chronic obstructive pulmonary disease (in Chinese)	B
38	The correlational study of severity and QoL of stable phase chronic obstructive pulmonary disease patients (in Chinese)	B
39	Analysis on quality of life and its influencing factors in patients with stable chronic obstructive pulmonary disease (in Chinese)	B
40	Analysis on quality of life of patients with chronic obstructive pulmonary disease and its influencing factors (in Chinese)	B
41	Investigation and analysis on the quality of life and influence factors in patients with COPD (in Chinese)	B
42	Quality of life and coping style in patients with chronic obstructive pulmonary disease (in Chinese)	B
43	Evaluation and analysis on quality of life and influencing factors of patients with chronic obstructive pulmonary disease (in Chinese)	B
44	Quality of life and its related factors in patients of stable chronic obstructive pulmonary disease (in Chinese)	B
45	Survey of the quality of life and social supports of patients with chronic obstructive pulmonary disease in community (in Chinese)	B
46	Application of COPD-specific version of the St George’s Respiratory Questionnaire in evaluating quality of life among COPD patients in Guangzhou (in Chinese)	B
47	The quality of life of patients with chronic obstructive pulmonary disease and correlated factors (in Chinese)	A

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