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IntroductionGood clinical-practice guidelines (CPGs) comprise systematic summaries of up-to-date knowledge and evidence for the diag-nosis, treatment, and prevention of diseases, and are the most-important references for decision-making in real-world clinical prac-tice. Over the past 2 decades, the number of CPGs issued worldwide has consistently increased—from fewer than 100 in 1990, to more than 1,000 in 2010.1 This soaring number of CPGs reflects not only the rapid progress being made in clinical research, especially in randomized clinical trials (RCTs), which are major reference sources with which to update CPGs, but also the increasing need for authoritative, worldwide standards to guide the updating of CPGs with the best knowledge and data available. Most published CPGs have been developed and issued by well-known medical organi-zations from the European Union (EU) or the USA.2 With the increasing globalization of clinical research, the number of interna-tional clinical trials involving China and other developing countries, as well as the number of participants from these regions,

has substantially increased.3,4 This trend has improved the availability of clinical evidence from various populations and globalized the applicability of updated EU and US CPGs.

The globalization of EU and US CPGs is driven by several factors. Firstly, the world- wide epidemic of health problems, especially chronic diseases such as cardio vascular disease (CVD), diabetes mellitus, and cancer, means that the burden of these diseases has increased in developing countries.5 The second driving force is the global market-ing strategies of pharma ceutical and med-ical-equipment companies. Novel drugs, devices, and technologies can be readily recognized and sold around the world when they are recommended in updated CPGs. Thirdly, professional medical orga-nizations in the EU and the USA now place more attention than in the past on exporting technology and enhancing the internationa-lization of CPGs through various academy activities, such as inter national conferences or symposia. Fourthly, the accessibility of EU and US CPGs has dramatically increased with the development of communication techno logy, such as the Internet. However, EU and US CPGs can encounter many bar-riers to practical global application. These

barriers vary substantially from country to country, and particularly between devel-oped and develop ing countries. In this Perspectives article, we discuss the main obstacles to the application of EU and US CPGs for CVD management from the unique perspective of China, describe some of the potential problems in the process of CPG globalization, and highlight the need to create localized CPGs in China and other developing countries.

EU and US CPGs in ChinaThe American College of Cardiology (ACC), American Heart Association (AHA), and the European Society of Cardio logy (ESC) are at the global forefront of develop ing and updating CPGs for CVD. The experts involved in the creation of the CPGs issued by these national and international orga-nizations are largely from the EU and the USA.6,7 The CPGs issued by the ACC, AHA, and ESC have long been important in Chinese clinical practice. In the official, web-based library (the China Guideline Clearinghouse8) of the evidence-based medicine council (the China Physician Association), 2,000 CPGs on a variety of medical indications have been collected. The majority are translations of EU and US CPGs; among the 106 CPGs for CVD, 52% are the Chinese versions of ones published by the ACC, AHA, or ESC, and 48% are CPGs or consensus documents issued by the Chinese Society of Cardiology.8 In addition, both clinical practice and many clinical and epidemiological studies in China have used EU and US CPGs as standards for diagnosis, treatment, and quality of care.9–11

Various potential reasons for the strong influence of EU and US CPGs in China exist. First, the disease spectrum and public- health issues in China have become increas-ingly similar to those in the EU and US populations. Second, the global availability of medical products has increased access in China to up-to-date diagnostic or treat-ment methods recommended by EU and US CPGs, especially in urban areas and large hospitals. Third, most RCT evidence comes from EU or US populations. Fourth, trans-lating EU and US CPGs into Chinese is easier and quicker than producing new CPGs when independent evidence from

OPINION

Barriers to translating EU and US CVD guidelines into practice in ChinaDong Zhao and Dayi Hu

Abstract | With the increasing globalization of clinical research and evidence, clinical-practice guidelines (CPGs) developed by the European Union (EU) and the USA are also becoming increasingly international. However, these CPGs can encounter barriers to their practical application. In this Perspectives article, we analyze the main obstacles to the application of EU and US CPGs for cardiovascular diseases from the unique perspective of China, and highlight some potential problems in the globalization of CPGs. Currently, China and other countries with limited independent evidence for CPG development must localize or adapt the CPGs developed by the EU, the USA, or international medical organizations, with systematic consideration of cost-effectiveness and alternative strategies on the basis of the available evidence from the native populations. At the same time, comprehensive capabilities to collect and review clinical evidence to produce population-specific CPGs should be developed.

Zhao, D. & Hu, D. Nat. Rev. Cardiol. 9, 425–429 (2012); published online 1 May 2012; doi:10.1038/nrcardio.2012.62

Competing interestsThe authors declare no competing interests.

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the Chinese population is lacking, and col-lecting that independent evidence is highly expensive. Fifth, the capacity for CPG pro-duction needs to be developed in China.

Despite the strong influence from EU and US CPGs, the situation is changing. Rapid social and economic development in China, as well as the globalization of medicine and medical-equipment markets, has substantially increased the capacity for clinical research and CPG development in China. Although most of the research on which clinical evidence is based is con-ducted in the EU and the USA, the number of phase III clinical trials involving China has increased. China participated in only 0.42% of all RCTs in 2000, but this increased to 6.3% in 2011 (Figure 1).12 In fact, China has the fastest-growing number of phase III clinical trials.12 The numbers of non-RCT studies, such as population-based observa-tional studies and large-scale patient regis-tries, which are essential sources of evidence for CPG development in China, have also increased substantially.13–16

Risk classification of patients for CVD is important to allow recommendations for diagnosis and treatment to be made. Individual risk is largely evaluated on the basis of long-term cohort studies or patient registries.14,17 Results of long-term cohort studies showed that classification of the risk of coronary heart disease (CHD) using observations from the US popula-tion notably overestimated the risk in the Chinese population.13 Data from large-scale patient registries in China have provided

valuable evidence on outcomes, the safety of medical products, and the status of CPG implementation in real-world clinical prac-tice.15,16 Meanwhile, the number of CPGs for the management of CHD (including acute myocardial infarction [MI], heart failure, hypertension, and dyslipidemia) developed by medical organizations in China has also increased substantially (Table 1).8,18,19

CPGs versus clinical practiceEven with the remarkable increase in the availability of CPGs, many studies have shown a huge gap between CPG recommen-dations (including those issued by the EU, the USA, and China) and their implemen-tation in clinical practice. In a study by the China Cholesterol Education Program,20 only 11% of patients at very high risk of CHD reached the target LDL-cholesterol levels recommended in the US CPGs of the Adult Treatment Panel (ATP) III.21 In a nation-wide Chinese study, only 2.7% of patients with atrial fibrillation received the warfarin therapy recommended in the rele vant CPGs issued by the ACC, AHA, or ESC.11

Several other national Chinese studies revealed that a low proportion of patients with ST-segment elevation MI (STEMI) were receiving the CPG-recommended treatment by primary percutaneous coro-nary intervention (PCI). In one study, from a total of 7,510 patients with STEMI in 274 hospitals, only 9.9% received primary PCI, whereas 62.4% of patients received reper-fusion therapy.22 In the Clinical Pathways for Acute Coronary Syndrome (CPACS)

study,23 investigators gathered data from 50 hospitals throughout China and found that only 16.3% of patients received primary PCI, whereas 36.0% of patients received reperfusion therapy. In the Bridging the Gap on CHD Secondary Prevention (BRIG) study,24 researchers investigated 65 hos-pitals in 31 provinces in China and found that only 2.5% of patients with STEMI who were admitted to secondary hospitals received the CPG-recommended emer-gency PCI. The CPACS and BRIG studies also indicated that <50% of eligible patients with CHD received the standardized drug therapy recommended in the US CPGs for secondary prevention of CHD.10,23

In another Chinese national study, 80% of patients with stroke were prescribed drugs that were not recommended by any CPGs.25 Although this gap between CPG recom-mendations and clinical practice also exists in the EU and the USA—where most of the guidelines are developed—the gap seems to be much wider in China. Translating EU and US CPGs into clinical practice in China is evidently much more difficult than simply translating the language of the CPGs from English into Chinese.

Barriers to CPG implementationThe barriers to the implementation of EU and US CPGs in China are complex. Many of them are closely related to the imperfect health-care system and problems rooted in rapid socioeconomic change, which might be similar in other developing countries.

Lack of CPG infrastructuresEU and US CPGs are based primarily on the availability of medical resources in the respective countries. Some recommen-dations are much more difficult to imp-lement in China than in the EU or the USA. For example, elevated troponin I or tro-ponin T levels are a necessary component for the diagnosis of acute MI according to CPGs from the AHA, ESC, and World Heart Federation.26 However, a nationwide survey in China showed that only 31.3% and 15.6% of secondary hospitals had the facilities to test troponin I and troponin T levels, respectively, in patients with sus-pected acute MI.23 The CPGs recommend that patients with STEMI should receive primary PCI, but among more than 1,000 hospitals equipped with angiographic facili-ties in China, many are not able, according to the China Ministry of Health, to perform PCI independently.27 Similarly, monitoring of glycated hemo globin (HbA1C) and serum

JapanUSA UKFrance

Germany

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of t

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Russia South AfricaEgyptCongo

China

200

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0

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2011

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Figure 1 | Total numbers of phase III clinical trials in China and other selected countries conducted in the past decade.

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glucose levels is recommended in US CPGs for the diagnosis of diabetes.28 However, the majority of patients with diabetes in China visit grass-roots hospitals, most of which lack the facilities to test HbA1C levels.

Consensus and conflict between CPGsIn 2009, a study showed that most of the rec-ommendations in the ACC and AHA CPGs were made on the basis of low-level evidence and were largely marked as ‘class C’ in terms of the strength of evidence.29 Class C indi-cates that not enough RCT evidence is avail-able, but that consensus exists between the experts. Certainly, consensus statements issued by the EU and the USA are developed with the health-care systems and clinical-practical experiences of those regions in mind. In addition, because of nonuniform CPG development and report formats, some substantial differences exist between the recommendations in EU and US CPGs.30,31 This disparity has created confusion among Chinese clinicians about how to judge or follow these CPGs in their clinical practice.

Ethnic variationThe recommendations in EU and US CPGs are made largely on the basis of the results of clinical trials involving populations from those regions. Particular drug-safety issues might exist when applying these recom-mendations to the Chinese population. For example, several studies suggested that Chinese patients with atrial fibrillation have more bleeding complications when they take warfarin at the doses recommended in EU and US CPGs.32–34 Different reactions to certain drugs come, at least partly, from ethnic genetic variation.35

Economic factorsEconomic factors can hinder the implemen-tation of CPGs in China. Although the per-centage of the Chinese population that has basic medical insurance is increasing drama-tically, the limited amount of reimbursement has resulted in financial difficulty for many patients with chronic diseases who require long-term medication. A number of studies have indicated that economic factors are of major importance to CPG adherence.10,36 One report from a survey of the micro-economic impact of CVD conducted in four low-income and middle-income countries revealed that the families of >50% of patients with acute MI or stroke in China were confronted with catastrophic health-care expenses, which were significantly associated with low income and rural status.36

Commercially driven practiceThe huge benefits from medical products have inevitably had a commercial impact on the pattern of clinical practice in China, especially with the lack of a strict monitoring system for quality of care. A profit-driven pattern of clinical practice results in overuse or underuse of various treatments and tests regardless of CPG recommendations.

Awareness of up-to-date CPGsMany studies have shown that physicians in primary-care hospitals in China have a very low awareness of up-to-date CPG recom-mendations, especially those from the EU or the USA that are published in English.37 Because medical-care resources and associ-ated continuing medical education tend to favor doctors in big cities and large hospitals, not only are the infrastructures and facilities of primary-care hospitals insufficient, but also the up-to-date knowledge of their clini-cians is inadequate.36 These factors reduce the appropriate application of CPGs.

Patient educationAn important barrier to CPG implementa-tion is lack of knowledge among patients about their diseases or the necessity of treatment. In a survey of 45,925 farmers in a rural area of Liaoning province of China, 40.2% of individuals with hypertension did not receive antihypertensive treatment because their lack of understanding about this harmful condition meant that they either did not seek medical advice, or did not adhere to medication when it was pre-scribed.38 In another survey, 53% of patients treated with catheter ablation for atrial fibrillation did not have enough knowledge for routine management of the disease.39 Some studies have found that patients who are poorly educated tend to have lower rates of adherence to treatment.10,39

Development of CPGs in ChinaDirect translation of EU and US CPGs might be advantageous if they are considered to be

the best source of all the up-to-date evidence that is available. The advantages include sharing of global evidence and the top expertise in CPG development to improve reliability, which depends on a standardized and transparent methodology for evidence evaluation and disclosure. This process avoids repetitive collection of evidence and updating of recommendations, promotes global, evidence-based clinical practices, and improves quality of care. In an analy-sis of the trend towards the globalization of clinical research, and its associated oppor-tunities and problems, internationa lization of CPGs was identified as an inevitable consequence.4 However, the barriers dis-cussed above can substantially obstruct the implemen tation and applicability of such CPGs in clinical practice in China. Localized CPGs are clearly needed.

To date, China has developed some highly influential CPGs, including those for the pre-vention and management of hyper tension40 and dyslipidemia.41 In recog nition of the confusion in dealing with class C recom-mendations from EU and US CPGs, increas-ing numbers of consensus statements for disease management, which combine the available evidence with clinical experience in China, have been issued. These CPGs were developed using evidence from the Chinese population whenever possible. Nevertheless, huge differences still exist between China and both the EU and the USA in the quan-tity and quality of clinical evidence and the capacity for CPG development. Some studies have shown that most RCT reports from China do not meet the international Consolidated Standards of Reporting Trials (CONSORT).42,43 One systematic review indicated that most of the RCTs of tradi-tional Chinese medicines for the treatment of stroke were of a low quality.44 Among the 6,747 systematic reviews in the Cochrane Library up to 2011, only 2.5% were from China, and even this figure is a remark-able increase from 0% in 2001.45 One study demonstrated that <5% of CPGs in China

Table 1 | Numbers of guidelines for selected areas of CVD from various cardiac societies

Guideline topic ACC and AHA18 ESC19 CSC8

Coronary heart disease 48 16 13

Heart failure 15 8 7

Hypertension 10 5 12

Dyslipidemia 21 1 9

Total 94 30 41

Abbreviations: ACC, American College of Cardiology; AHA, American Heart Association; CSC, Chinese Society of Cardiology; CVD, cardiovascular disease; ESC, European Society of Cardiology.

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were developed and reported according to internationally accepted, standardized pro-cesses.46 Therefore, medical professional organizations in China must develop com-prehensive capabilities in evidence produc-tion, collection, and review, as well as CPG development according to internationally accepted standards.

Conversely, for China independently to produce all CPG evidence according to data collected from the Chinese popula-tion is unnecessary and would not be cost-effective. Moreover, China is involved in a very small proportion of the total number of RCTs. Among 4,633 new RCTs in 2010 and 2011, China was involved in only 6%, but the EU and the USA were involved in 60%.12 Consequently, China might find it difficult to develop CPGs with enough independent evidence. A reasonable com-promise would be to localize or adapt EU or US CPGs (or those of other international medical organizations), with consideration of cost-effectiveness and alternative strat-egies, by using available RCTs, large-scale patient registries, and comparative effective-ness research (including traditional Chinese medicines) among Chinese patients. Some recommended methods for adapting CPGs are available.47

ConclusionsAlthough some advantages exist to trans-lating EU and US CPGs, considerable bar-riers that are closely associated with the imperfect health-care system and current socioeconomic circumstances impede the implementation of such CPGs in clinical practice in China. Development of Chinese CPGs with sufficient independent evidence is difficult. A reasonable compromise, there-fore, would be to localize or adapt EU or US CPGs by systematic assessment of the avail-able evidence from China, with consider-ation of cost-effectiveness and alternatives strategies, and to increase the capacities for both clinical research and CPG development in China. The production of CPGs that are applicable to Chinese clinical practice will help to improve the quality of patient care in China.

Department of Epidemiology, Capital Medical University Beijing Anzhen Hospital, Beijing Institute of Heart, Lung and Blood Vessel Diseases, No. 2 Anzhen Street, Chaoyang District, Beijing, 100029, China (D. Zhao). Cardiology Department, People’s Hospital of Peking University, 11# Xizhimen S. Avenue, Beijing, 100044, China (D. Hu). Correspondence to: D. Hu dayi.hu@medmail.com.cn

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Author contributionsD. Zhao researched the data for the article. Both authors contributed substantially to discussion of its content, writing the manuscript, and to reviewing and editing it before submission.

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The following letters have recently been published:Relationship between sleep quality and the level and pattern of BPYuli Huang, Weiyi Mai and Yunzhao Hudoi:10.1038/nrcardio.2011.202-c1

The author’s reply:Inadequate sleep equates to inadequate blood pressure controlGeorge L. Bakrisdoi:10.1038/nrcardio.2011.202-c2

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