Fighting the Health Challenges of Diabetes in Hong Kong: A Window Into Mainland China

The prevalence of diabetes has been escalating in recent decades. According to the eighth diabetes atlas of the International Diabetes Federation (IDF; http://diabetesatlas.org/resources/2017-atlas.html), diabetes affected more than 425 million adults worldwide in 2017, and the number of individuals affected will reach 629 million by 2045 if the trajectory continues. The global health care cost resulting from treatment of diabetes and its complications reached $727 billion in 2017, representing an 8% rise since 2015. These alarming statistics call for urgent public health measures to halt the diabetes pandemic.

In China alone, more than 114 million people had diabetes in 2017, making up one quarter of the world’s diabetes population. A national survey conducted in 2010¹ showed that the crude diabetes prevalence in China was 9.8% according to the World Health Organization’s criteria and 11.2% if HbA1c levels of 6.5% or above were included in diagnoses. These figures represent a dramatic increase since the 1980s, when the prevalence was under 1%; however, they are remarkably similar to figures in Hong Kong in the mid-1990s,² probably reflecting genetic similarities but temporal differences in economic growth between Hong Kong and other Chinese cities.

The Hong Kong Cardiovascular Risk Factor Prevalence Study (CRISPS), a community-based age- and sex-stratified randomized study with prospective follow-ups,^2–5 has been conducted since 1995. CRISPS data show that 9.8% of Hong Kong Chinese residents had diabetes in 1995 to 1996 according to the World Health Organization’s criteria. The independent diabetes risk factors revealed in the earlier-described national survey were similar to those revealed in CRISPS,³ including older age, obesity, male gender, family history of diabetes, hypertension, and dyslipidemia. Rapid urbanization and socioeconomic changes, unhealthy eating habits and increasingly sedentary lifestyles leading to excess adiposity and insulin resistance, and population aging likely account for the rising diabetes prevalence in China, including Hong Kong.

The IDF atlas also reports that 50% of diabetes cases worldwide are undiagnosed and that 7.3% of individuals have impaired glucose tolerance. The prevalence of undiagnosed diabetes was 53.6% in China in 2017 and 54.1% in Hong Kong in 2014 to 2015 (http://www.chp.gov.hk). Because type 2 diabetes is largely asymptomatic, individuals with this form of the disease might be diagnosed only when they present with diabetic complications. Impaired glucose tolerance is a type of prediabetes. Prediabetes carries an increased risk of diabetes,³ cardiovascular diseases,⁴ and long-term mortality, all of which can be reduced through intensified lifestyle modifications (Table A, available as a supplement to the online version of this article at http://www.ajph.org). In China, the prevalence of prediabetes was 51% in 2010,¹ with a similar prevalence found in Hong Kong in 2010 to 2012.⁴

The high prevalence of undiagnosed diabetes and prediabetes globally suggests that the health burden due to the diabetes epidemic will continue to rise. Prediabetes and diabetes share similar risk factors. Population-based strategies to reduce both conditions include provision of parks for regular exercise, provision of free or subsidized exercise facilities, and provision of healthy school lunch subsidies. A life-course approach should be adopted, with education and preventive programs taking place in schools, workplaces, and communities.

Regular screening of high-risk individuals, identified via simple Web-based tests such as the American Diabetes Association’s diabetes risk test, can lead to early diagnoses of both prediabetes and diabetes. Asians, including those of Chinese descent, are at a higher metabolic risk of diabetes than Caucasians of a similar body mass index. When Asian-specific body mass index cutoffs (normal weight defined as less than 23 kg/m²) are used, as recommended by the American Diabetes Association, the diabetes risk test is effective in diagnosing Hong Kong Chinese individuals.⁵

According to the Hong Kong diabetes database, which includes the electronic health records of 338 908 Chinese patients receiving regular screening for diabetes complications at Hospital Authority public health clinics, the incidence of (and mortality related to) end-stage renal disease and cardiovascular complications decreased between 2000 and 2012.⁶ Also, the percentage of patients achieving metabolic and risk factor goals improved; for example, the percentage of patients with HbA1c levels below 7% increased from 32.9% to 50%. This was partly attributable to more liberal use of antidiabetic agents, renin–angiotensin system blockers, and statins.

Nonetheless, the contribution of improved diabetes management should not be underestimated. Before the mid-1990s, diabetes management in Hong Kong was entirely doctor centered, and specialist diabetes clinics were packed with patients. Even those with mild or stable disease refused to be referred to primary care clinics, which they considered to provide an inferior quality of care. Specialist diabetes nursing and associated training started in 1988, and the first diabetes center—with patient education and management provided by a multidisciplinary team consisting of diabetologists, diabetes nurses, dietitians, and podiatrists—was established at Queen Mary Hospital in 1994. Currently there are diabetes centers in all of Hong Kong’s major public hospitals, reducing hospital admissions, empowering patients with diabetes knowledge and self-management skills, and providing screening for diabetes complications.

The Hong Kong diabetes database also includes patients from public primary care clinics that are part of the Multidisciplinary Risk Assessment and Management Program for Patients with Diabetes Mellitus.⁶ This program, which involves a multidisciplinary, risk-stratified, and protocol-driven approach to diabetes management, including regular screenings for diabetic complications, has also contributed to reductions in diabetes complications, specialist referrals, and hospital admissions.

Training of primary care clinic doctors and nurses has improved, partly as a result of visiting teams from diabetes centers conducting insulin clinics for patients with treatment difficulties. Agreed-on clinical pathways for patient referrals are established such that patients with different treatment needs can be managed optimally in appropriate care settings.

In addition, the Reference Framework for Diabetes Care for Adults in Primary Care Settings (http://www.pco.gov.hk) was published in 2010. This resource offers detailed, evidence-based information on prevention and control of diabetes and is updated regularly to provide diabetes management guidance for the primary care sector.

As a city that has undergone rapid socioeconomic transitions, Hong Kong’s problems and efforts in combating the diabetes epidemic may reflect on the challenges faced by the rest of China. Our experience suggests that a well-organized primary care system in which there are close interactions with secondary care providers can contribute tremendously toward reducing the health consequences of diabetes through early and optimal metabolic control and timely detection and treatment of complications.

In Mainland China, where the primary health care system is undergoing reform, there are still multiple issues that limit its readiness to contribute to the care of one quarter of the world’s diabetes population.⁷ For example, the higher reimbursement caps for outpatient and inpatient care in hospitals lead to inappropriate use of specialist services.⁷ Nonetheless, the Healthy China 2030 plan,⁷ which focuses on the primary health care system and its efforts to address the health burden and high cost of chronic noncommunicable diseases such as diabetes, is certainly a step in the right direction.