Kit Yee Chan

Epidemiology of Alzheimer's disease and other forms of dementia in China, 1990-2010: a systematic review and analysis.

BACKGROUND China is increasingly facing the challenge of control of the growing burden of non-communicable diseases. We assessed the epidemiology of Alzheimers disease and other forms of dementia in China between 1990, and 2010, to improve estimates of the burden of disease, analyse time trends, and inform health policy decisions relevant to Chinas rapidly ageing population. METHODS In our systematic review we searched for reports of Alzheimers disease or dementia in China, published in Chinese and English between 1990 and 2010. We searched China National Knowledge Infrastructure, Wanfang, and PubMed databases. Two investigators independently assessed case definitions of Alzheimers disease and dementia: we excluded studies that did not use internationally accepted case definitions. We also excluded reviews and viewpoints, studies with no numerical estimates, and studies not done in mainland China. We used Poisson regression and UN demographic data to estimate the prevalence (in nine age groups), incidence, and standardised mortality ratio of dementia and its subtypes in China in 1990, 2000, and 2010. FINDINGS Our search returned 12,642 reports, of which 89 met the inclusion criteria (75 assessed prevalence, 13 incidence, and nine mortality). In total, the included studies had 340,247 participants, in which 6357 cases of Alzheimers disease were recorded. 254,367 people were assessed for other forms of dementia, of whom 3543 had vascular dementia, frontotemporal dementia, or Lewy body dementia. In 1990 the prevalence of all forms of dementia was 1·8% (95% CI 0·0-44·4) at 65-69 years, and 42·1% (0·0-88·9) at age 95-99 years. In 2010 prevalence was 2·6% (0·0-28·2) at age 65-69 years and 60·5% (39·7-81·3) at age 95-99 years. The number of people with dementia in China was 3·68 million (95% CI 2·22-5·14) in 1990, 5·62 million (4·42-6·82) in 2000, and 9·19 million (5·92-12·48) in 2010. In the same period, the number of people with Alzheimers disease was 1·93 million (1·15-2·71) in 1990, 3·71 million (2·84-4·58) people in 2000, and 5·69 million (3·85-7·53) in 2010. The incidence of dementia was 9·87 cases per 1000 person-years, that of Alzheimers disease was 6·25 cases per 1000 person-years, that of vascular dementia was 2·42 cases per 1000 person-years, and that of other rare forms of dementia was 0·46 cases per 1000 person-years. We retrieved mortality data for 1032 people with dementia and 20,157 healthy controls, who were followed up for 3-7 years. The median standardised mortality ratio was 1·94:1 (IQR 1·74-2·45). INTERPRETATION Our analysis suggests that previous estimates of dementia burden, based on smaller datasets, might have underestimated the burden of dementia in China. The burden of dementia seems to be increasing faster than is generally assumed by the international health community. Rapid and effective government responses are needed to tackle dementia in low-income and middle-income countries. FUNDING Nossal Institute of Global Health (University of Melbourne, Australia), the National 12th Five-Year Major Projects of China, National Health and Medical Research Council Australia-China Exchange Fellowship, Importation and Development of High-Calibre Talents Project of Beijing Municipal Institutions, and the Bill & Melinda Gates Foundation.

A method for the quantitative analysis of the layering of HIV-related stigma

HIV-related stigma is regarded as one of the major barriers in the development of effective prevention and care programs; but the stigma associated with HIV stigma is not a singular entity. The stigma of the infection is layered with other stigmas, such as those associated with the routes of transmission (e.g., sex work and injecting drug use) and personal characteristics (e.g., race, religion, ethnicity and gender). In developing programs and policies to overcome HIV-related stigma, cognisance needs to be taken of all the sources of stigma, and how they may interact. A novel method is described for examining the layers of HIV/AIDS-related stigma, and secondary data are adapted to illustrate this. The importance of understanding the layering of stigma for the development of effective interventions is also discussed.

Causes of deaths in children younger than 5 years in China in 2008

BACKGROUND Previous estimates of the global burden of disease for children have not included much information from China, leading to a large gap in data. We identified the main causes of deaths in neonates (<1 month), postneonatal infants (1-11 months), and children (<5 years) in China using information that was available to the public. METHODS The Child Health Epidemiology Reference Group in collaboration with colleagues from Peking University systematically searched Chinese databases that were available to the public. Information was obtained from the Chinese Ministry of Health and Bureau of Statistics websites, Chinese National Knowledge Infrastructure database, and Chinese Health Statistics yearbooks for 1990-2008. We also obtained information from 206 high-quality community-based longitudinal studies of different causes of deaths in children (<5 years) that were written in the Chinese language. A statistical model was developed to estimate the total number of deaths in children according to provinces, age groups, and main causes. FINDINGS During 1990-2008, the mortality rates in neonates, postneonatal infants, and children were reduced by 70% (from 34.0 to 10.2 per 1000 livebirths), 72% (from 53.5 to 14.9 per 1000 livebirths), and 71% (from 64.6 to 18.5 per 1000 livebirths), respectively, meeting the targets set in the Millennium Development Goal 4. The leading causes of deaths in 2008 were pneumonia, birth asphyxia, and preterm birth complications, each accounting for 15-17% of all deaths. Congenital abnormalities and accidents increased in importance during this period, contributing to 11% and 10% of child deaths, respectively. Sudden infant death syndrome contributed to 5% of deaths in children. INTERPRETATION Publically available Chinese databases contain much important information that has been underused in the estimation of global and regional burden of disease. On the basis of trends, preterm birth complications are expected to become the leading cause of child mortality in China, whereas deaths from congenital abnormalities, accidents, and sudden infant death syndrome are predicted to continue increasing in importance in the long term. FUNDING Bill & Melinda Gates Foundation.

Setting Research Priorities to Reduce Global Mortality from Childhood Pneumonia by 2015

Igor Rudan and colleagues report the results of their consensus building exercise that identified health research priorities to help reduce child mortality from pneumonia.

Global and regional estimates of COPD prevalence: Systematic review and meta-analysis

Background The burden of chronic obstructive pulmonary disease (COPD) across many world regions is high. We aim to estimate COPD prevalence and number of disease cases for the years 1990 and 2010 across world regions based on the best available evidence in publicly accessible scientific databases. Methods We conducted a systematic search of Medline, EMBASE and Global Health for original, population–based studies providing spirometry–based prevalence rates of COPD across the world from January 1990 to December 2014. Random effects meta–analysis was conducted on extracted crude prevalence rates of COPD, with overall summaries of the meta–estimates (and confidence intervals) reported separately for World Health Organization (WHO) regions, the World Banks income categories and settings (urban and rural). We developed a meta–regression epidemiological model that we used to estimate the prevalence of COPD in people aged 30 years or more. Findings Our search returned 37 472 publications. A total of 123 studies based on a spirometry–defined prevalence were retained for the review. From the meta–regression epidemiological model, we estimated about 227.3 million COPD cases in the year 1990 among people aged 30 years or more, corresponding to a global prevalence of 10.7% (95% confidence interval (CI) 7.3%–14.0%) in this age group. The number of COPD cases increased to 384 million in 2010, with a global prevalence of 11.7% (8.4%–15.0%). This increase of 68.9% was mainly driven by global demographic changes. Across WHO regions, the highest prevalence was estimated in the Americas (13.3% in 1990 and 15.2% in 2010), and the lowest in South East Asia (7.9% in 1990 and 9.7% in 2010). The percentage increase in COPD cases between 1990 and 2010 was the highest in the Eastern Mediterranean region (118.7%), followed by the African region (102.1%), while the European region recorded the lowest increase (22.5%). In 1990, we estimated about 120.9 million COPD cases among urban dwellers (prevalence of 13.2%) and 106.3 million cases among rural dwellers (prevalence of 8.8%). In 2010, there were more than 230 million COPD cases among urban dwellers (prevalence of 13.6%) and 153.7 million among rural dwellers (prevalence of 9.7%). The overall prevalence in men aged 30 years or more was 14.3% (95% CI 13.3%–15.3%) compared to 7.6% (95% CI 7.0%–8.2%) in women. Conclusions Our findings suggest a high and growing prevalence of COPD, both globally and regionally. There is a paucity of studies in Africa, South East Asia and the Eastern Mediterranean region. There is a need for governments, policy makers and international organizations to consider strengthening collaborations to address COPD globally.

Research priorities for health of people with disabilities: an expert opinion exercise

International evidence shows that people with disabilities have many unmet health and rehabilitation needs, face barriers in accessing mainstream health-care services, and consequently have poor health. Inadequate specific information is available about the prevalence and patterns of health conditions of people with disabilities, effective interventions, and policy-relevant research about what works to improve health and functioning of people with disabilities. In view of the urgency of the issues at stake and scarcity of resources, research contributing to improvement of health of people with disabilities needs to be prioritised. We invited 82 stakeholders to list and score research options, with the priority-setting method of the Child Health and Nutrition Research Initiative. 83 research questions were assessed for answerability, applicability, sensitivity, support within the context, and equity. The leading research priority was identification of barriers that people with disabilities have in accessing health services at different levels, and finding the best possible strategies to integrate their needs into primary health-care systems and ensure local delivery. Results showed that addressing specific impairments is secondary to ensuring that health systems provide adequately for all people with disabilities. Our findings are a call for urgent attention to the issue of access to appropriate health care for people with disabilities, especially in low-income and middle-income countries.

Setting Research Priorities to Reduce Almost One Million Deaths from Birth Asphyxia by 2015

Joy Lawn and colleagues used a systematic process developed by the Child Health Nutrition Research Initiative (CHNRI) to define and rank research options to reduce mortality from intrapartum-related neonatal deaths (birth asphyxia) by the year 2015.

Research priorities to reduce global mortality from newborn infections by 2015.

Background: Newborn infections are responsible for approximately one-third of the estimated 4.0 million neonatal deaths that occur globally every year. Appropriately targeted research is required to guide investment in effective interventions, especially in low resource settings. Setting global priorities for research to address neonatal infections is essential and urgent. Methods: The Department of Child and Adolescent Health and Development of the World Health Organization (WHO/CAH) applied the Child Health and Nutrition Research Initiative (CHNRI) priority-setting methodology to identify and stimulate research most likely to reduce global newborn infection-related mortality by 2015. Technical experts were invited by WHO/CAH to systematically list and then use standard methods to score research questions according to their likelihood to (i) be answered in an ethical way, (ii) lead to (or improve) effective interventions, (iii) be deliverable, affordable, and sustainable, (iv) maximize death burden reduction, and (v) have an equitable effect in the population. The scores were then weighted according to the values provided by a wide group of stakeholders from the global research priority-setting network. Findings: On a 100-point scale, the final priority scores for 69 research questions ranged from 39 to 83. Most of the 15 research questions that received the highest scores were in the domain of health systems and policy research to address barriers affecting existing cost-effective interventions. The priority questions focused on promotion of home care practices to prevent newborn infections and approaches to increase coverage and quality of management of newborn infections in health facilities as well as in the community. While community-based intervention research is receiving some current investment, rigorous evaluation and cost analysis is almost entirely lacking for research on facility-based interventions and quality improvement. Interpretation: Given the lack of progress in improving newborn survival despite the existence of effective interventions, it is not surprising that of the top ranked research priorities in this article the majority are in the domain of health systems and policy research. We urge funding agencies and investigators to invest in these research priorities to accelerate reduction of neonatal deaths, particularly those due to infections.

Institutional and structural forms of HIV-related discrimination in health care : a study set in Beijing

Abstract This paper presents key findings of a situational analysis of institutional and structural levels of HIV/AIDS-related discrimination in Beijing, China, with a focus on the area of health care. Initially slow to respond to the presence of HIV, China has altered its approach and enacted strict legislative protection for people living with HIV/AIDS (PLWHA). In order to determine whether this has altered discrimination against PLWHA, this study examined existing legislation and policy, and interviewed key informants working in health care and PLWHA. The overall findings revealed that discrimination in its many forms continued to occur in practice despite Chinas generally strong legislative protection, and it is the actual practice that is hindering PLWHAs’ access to health services. A number of legislative and policy gaps that allow discrimination to occur in practice were also identified and discussed. The paper concludes with a call to rectify specific gaps between legislation, policy and practice. An understanding of the underlying factors that drive discrimination will also be necessary for effective strategic interventions to be developed and implemented.

Research priorities to reduce the global burden of dementia by 2025

At the First WHO Ministerial Conference on Global Action Against Dementia in March, 2015, 160 delegates, including representatives from 80 WHO Member States and four UN agencies, agreed on a call for action to reduce the global burden of dementia by fostering a collective effort to advance research. To drive this effort, we completed a globally representative research prioritisation exercise using an adapted version of the Child Health and Nutrition Research Initiative method. We elicited 863 research questions from 201 participants and consolidated these questions into 59 thematic research avenues, which were scored anonymously by 162 researchers and stakeholders from 39 countries according to five criteria. Six of the top ten research priorities were focused on prevention, identification, and reduction of dementia risk, and on delivery and quality of care for people with dementia and their carers. Other priorities related to diagnosis, biomarkers, treatment development, basic research into disease mechanisms, and public awareness and understanding of dementia. Research priorities identified by this systematic international process should be mapped onto the global dementia research landscape to identify crucial gaps and inform and motivate policy makers, funders, and researchers to support and conduct research to reduce the global burden of dementia. Efforts are needed by all stakeholders, including WHO, WHO Member States, and civil society, to continuously monitor research investments and progress, through international platforms such as a Global Dementia Observatory. With established research priorities, an opportunity now exists to translate the call for action into a global dementia action plan to reduce the global burden of dementia.