Cohort Profile: Hong Kong Department of Health Elderly Health Service Cohort.

The Department of Health Elderly Health Service Cohort in Hong Kong was set up to promote understanding of ageing in a global context, to exploit the role of Hong Kong as a sentinel for populations currently experiencing very rapid economic development, to provide a developed non-Western 'social laboratory' where empirically derived hypotheses can be tested and to leverage the different patterns of common chronic diseases between East and West to generate novel hypotheses about their determinants. The initial cohort enrolled from July 1998 to the end of December 2001 includes 66 820 people aged 65 years or older, forming about 9% of the population of this age. A comprehensive health assessment was made at enrollment and then repeated regularly on an ongoing basis. The health assessment included a comprehensive assessment of lifestyle, social circumstances, physical health and mental health, including an assessment of cognition and depressive symptoms. Health services use and deaths have been obtained by record linkage and confirmed, where necessary, by telephone interview. Currently, the data are not publicly available; we would welcome collaborations and research proposals.

Preliminary epidemiological assessment of MERS-CoV outbreak in South Korea, May to June 2015.

South Korea is experiencing the largest outbreak of Middle East respiratory syndrome coronavirus infections outside the Arabian Peninsula, with 166 laboratory-confirmed cases, including 24 deaths up to 19 June 2015. We estimated that the mean incubation period was 6.7 days and the mean serial interval 12.6 days. We found it unlikely that infectiousness precedes symptom onset. Based on currently available data, we predict an overall case fatality risk of 21% (95% credible interval: 14­31).

Systematic differences among never, occasional and moderate alcohol users in southern China, and its use in alcohol research: a cross-sectional study.

BACKGROUND: Western observational studies show moderate alcohol use, compared with never use, positively associated with health. Moderate users differ systematically from others, making these observations vulnerable to confounding. Observations from other contexts may help distinguish whether these associations are confounded. To assess whether southern Chinese would provide a more suitable setting to examine the association of moderate alcohol use with health, we compared never alcohol users with moderate alcohol users and occasional users in this setting. METHODS: We used age-adjusted multinomial regression to assess sex-stratified associations of alcohol use (never, occasional (<1 occasion/week), moderate (≤140 g ethanol/week for women and ≤210 g for men)) with health attributes and indicators in the Guangzhou Biobank Cohort Study (2003-2008) (n=26 361). RESULTS: Among men, moderate alcohol users, when compared with never users, had slightly lower socioeconomic position and unhealthier lifestyle. Conversely, occasional alcohol users, when compared with never users, had higher socioeconomic position and healthier lifestyle. Among women, when compared with never users, both occasional and moderate users had higher socioeconomic position and healthier lifestyle. However, all alcohol users for both sexes, when compared with never users, were more likely to be ever smokers and to be exposed to secondhand smoke. CONCLUSIONS: Observations in alcohol epidemiology may be affected by confounding due to contextually specific systematic differences. Results from a particular setting should not be interpreted as causal unless they are verified in different populations and, preferably, in non-observational studies.

Are the 2006 World Health Organization standards for infant growth applicable to Hong Kong Chinese? Universalistic standards or epidemiological transition stage-specific norms.

1. Parental socio-economic status was positively associated with length and body mass index of Hong Kong Chinese infants at 9 months. 2. Maternal smoking in pregnancy was negatively associated with infant length at 9 months. 3. Some of the World Health Organization (WHO) criteria for an optimal nurturing environment contributed positively to growth. At 36 months, Hong Kong Chinese infants were generally shorter and fatter than the WHO growth references.

Perspectives on family health, happiness and harmony (3H) among Hong Kong Chinese people: a qualitative study.

Family harmony, an important Confucian ideal in Chinese society is believed to determine family happiness and therefore health, but is this accurate? This is a qualitative study of 41 Hong Kong Chinese family members. Individual recorded interviews were thematically analysed describing perceived interactions between harmony, happiness and health. Family harmony comprised four components: communication, mutual respect, lack of conflict and family time [notably 'Gou tong' (in Cantonese )-opportunity and willingness to spend time together-requiring good interpersonal communication, emphasized by female respondents]. Lack of conflict was emphasized, while diverse values, parenting styles and financial difficulties were common causes of conflict. Respect required reciprocity. Family happiness comprised four elements: family harmony, an important pre-requisite; mutual caring and supportive orientation; sense of security emphasizing financial security in middle-class versus sense of togetherness in lower social class groups and contentment. Healthy families were harmonious; 'typical' (children/two-parent/two-grandparent); happy; caring and respectful, with individual health and healthy behaviours. Family harmony, happiness and health are interrelated and built on a communicative, respectful, caring and contented set of attitudes, in particular allowing for family time. Harmony is apparently a core element of good family functioning.

Optimal design of studies of influenza transmission in households. I: case-ascertained studies.

Case-ascertained household transmission studies, in which households including an 'index case' are recruited and followed up, are invaluable to understanding the epidemiology of influenza. We used a simulation approach parameterized with data from household transmission studies to evaluate alternative study designs. We compared studies that relied on self-reported illness in household contacts vs. studies that used home visits to collect swab specimens for virological confirmation of secondary infections, allowing for the trade-off between sample size vs. intensity of follow-up given a fixed budget. For studies estimating the secondary attack proportion, 2-3 follow-up visits with specimens collected from all members regardless of illness were optimal. However, for studies comparing secondary attack proportions between two or more groups, such as controlled intervention studies, designs with reactive home visits following illness reports in contacts were most powerful, while a design with one home visit optimally timed also performed well.

Patterns of and hypotheses for infection-related cancers in a Chinese population with rapid economic development.

With economic development, non-communicable diseases replace infectious diseases as the leading cause of death; how such transition occurs for infectious diseases with long latency has rarely been considered. We took advantage of a Chinese population with rapid economic development in the mid-20th century to study changing patterns of infection-related cancers. We used sex-specific Poisson regression to estimate age, period and cohort effects on adult deaths 1976-2005 from eight infection-related cancers in Hong Kong. Cervical, head and neck, and oesophageal cancers, associated with sexually transmitted infections, decreased for the first birth cohorts with sexual debut in a more developed environment. Leukaemia and non-Hodgkin's lymphoma, associated with vertically transmitted infections, decreased for the first cohorts born into a more developed environment. Birth cohort patterns were unclear for nasopharyngeal, stomach and liver cancers. Mortality rates for cancers related to early infections may depend on population history, with delayed reductions for some infection-related cancers.

Hong Kong Chinese community leaders' perspectives on family health, happiness and harmony: a qualitative study.

This paper examines the views of Hong Kong community leaders on the underlying issues that affect family health, happiness and harmony (3Hs) in Hong Kong. Using a community reconnaissance method, a series of individual in-depth interviews with 26 leaders that represent neighbourhoods of diverse socio-economic status (SES) from June to August 2008 were conducted. Participants considered that changing family structure, economic situation and strong work ethic are the most salient factors that affect family 3Hs. The deprived comprehensive social security assistance recipients, single-parent families and migrant women were considered to be the most vulnerable groups to breakdown in family 3Hs and particularly, they lack family resources. Families from different SES have to overcome different challenges in order to achieve and sustain family 3Hs. Leaders from low SES neighbourhood were concerned more about providing tangible help such as child care facilities to improve family resources, whereas leaders from high SES neighbourhood focused more on preventive interventions such as education on relationship skills to achieve better family well-being. The findings offer insights in designing effective social marketing education campaigns and family-friendly workplace policy to promote social harmony through the maintenance of 3Hs families.

Childhood meat eating and inflammatory markers: the Guangzhou Biobank Cohort Study.

BACKGROUND: We hypothesized that socio-economic development could, via nutritionally driven levels of pubertal sex-steroids, promote a pro-inflammatory state among men but not women in developing countries. We tested this hypothesis, using recalled childhood meat eating as a proxy for childhood nutrition, in southern China. METHODS: We used multivariable linear regression in the Guangzhou Biobank Cohort Study phase 3 (2006-8) to examine the adjusted associations of recalled childhood meat eating, <1/week (n = 5,023), about once per week (n = 3,592) and almost daily (n = 1,252), with white blood cell count and its differentials among older (≥ 50 years) men (n = 2,498) and women (n = 7,369). RESULTS: Adjusted for age, childhood socio-economic position, education and smoking, childhood meat eating had sex-specific associations with white blood cell count and lymphocyte count, but not granulocyte count. Men with childhood meat eating almost daily compared to <1/week had higher white blood cell count (0.33 109/L, 95% confidence interval (CI) 0.10 to 0.56) and higher lymphocyte count (0.16 109/L, 95% CI 0.07 to 0.25). Adjustment for obesity slightly attenuated these associations. CONCLUSION: If confirmed, this hypothesis implies that economic development and the associated improvements in nutrition at puberty may be less beneficial among men than women; consistent with the widening sex differentials in life expectancy with economic development.

Leg length and age of puberty among men and women from a developing population: the Guangzhou Biobank Cohort study.

OBJECTIVES: Leg length and relative leg length are considered to be reliable markers of prepubertal living conditions. Cessation of leg growth, driven by estrogen, occurs earlier in puberty in girls than boys. We hypothesized that leg length and relative leg length, as sitting height to leg ratio, might have sex-specific associations with age of puberty. METHODS: We used multivariable linear regression in 10,046 older (>or=50 years) Chinese from the Guangzhou Biobank Cohort Study (Phase 3) to examine the associations of recalled age of puberty (women: age of menarche, and men: mean age of first nocturnal emission, voice breaking, and first pubic hair) with subischeal leg length, sitting height to leg ratio, and sitting height. RESULTS: Leg length and sitting height to leg ratio had different associations with age of puberty in men and women (P-values for interaction <0.001), but sitting height did not. Per year earlier puberty, legs were longer among men by 0.09 cm (95% confidence interval (CI) 0.01-0.18) and shorter among women by -0.16 cm (95% CI -0.20 to -0.12). Further adjustment for age, hip size (as a marker of buttock fat), and several markers of childhood conditions did not obviate the difference in association by sex. CONCLUSIONS: Adult leg length and relative leg length (sitting height to leg ratio) may be biomarkers of different exposures in men and women, with corresponding implications for their interpretation as a biomarker of early life exposures.

A socio-biological explanation for social disparities in non-communicable chronic diseases: the product of history?

This study places social disparities in the major non-communicable chronic diseases within their global economic and historical contexts. Rapid economic transition outside the developed world provides a unique opportunity to re-examine the origins of, and biological mechanisms driving, social disparities. Gaps in prevailing theories focusing on material resources, civic infrastructure and social structure are identified. Using longstanding experimental evidence and epigenetic theories, it is suggested that exposure to economic development over generations (ie, improved living conditions over historical time) could by acting on different biological axes (somatotrophic and gonadotrophic) generate specific patterns of social disparities. Moreover, these same processes could initially generate a transient epidemic of diabetes as well as a permanent increase in male risk of premature ischaemic heart disease. As such, this study demonstrates the importance of context, and implies that current evidence from the developed world may be largely uninformative for preventing or mitigating social disparities in non-communicable chronic diseases elsewhere, suggesting research efforts should be focused on developing countries.

A socio-historical hypothesis for the diabetes epidemic in Chinese--preliminary observations from Hong Kong as a natural experiment.

It has been hypothesized that the emerging epidemic of diabetes in economically transitioning or recently transitioned populations is due to mismatch between developmental and mature environments. We took advantage of migration within an ethnically homogenous population to investigate this hypothesis, and the potentially modifying role of postnatal growth conditions, proxied by greater height. We used multivariable logistic regression in a population-based cross-sectional study from 1994 to 1996 of 2,341 long-term Hong Kong residents aged 25-74 years, either born in contemporaneously developed Hong Kong or migrants from economically undeveloped Guangdong. Migrant status was not associated with clinically diagnosed diabetes, odds ratio 1.05 (95% confidence interval 0.69-1.58) in adult migrants compared to Hong Kong-born natives and 1.22 (0.83-1.80) in preadult migrants, adjusted for age, sex, socio-economic position, and lifestyle. However, the association of diabetes with migrant status varied with height, suggesting a potentially complex relationship between indicators of prenatal and postnatal nutritional exposures. Compared to tall Hong Kong-born natives, the odds ratio of diabetes was 2.36 (1.20-4.61) in tall migrants, 1.94 (1.07-3.53) in short Hong Kong-born natives, but 1.04 (0.48-2.23) in short adult migrants. Additionally adjusting for body mass index and waist-hip ratio had little effect, apart from attenuating the association between short height and diabetes prevalence in Hong Kong-born natives. Whether the current epidemic of diabetes is a long-standing effect of such mismatch or a "first-generation through effect" generated by rapid economic development causing disproportionate growth remains to be determined.

Hong Kong's domestic health spending--financial years 1989/90 through 2004/05.

This report presents the latest estimates of Hong Kong's domestic health spending between fiscal years 1989/90 and 2004/05, cross-stratified and categorised by financing source, provider and function on an annual basis. Total expenditure on health was HK$67,807 million in fiscal year 2004/05. In real terms, total expenditure on health showed positive growth averaging 7% per annum throughout the period covered in this report while gross domestic product grew at 4% per annum on average, indicating a growing percentage of health spending relative to gross domestic product, from 3.5% in 1989/90 to 5.2% in 2004/05. This increase was largely driven by the rise in public spending, which rose 9% per annum on average in real terms over the period, compared with 5% for private spending. This represents a growing share of public spending from 40% to 55% of total expenditure on health during the period. While public spending was the dominant source of health financing in 2004/05, private household out-of-pocket expenditure accounted for the second largest share of total health spending (32%). The remaining sources of health finance were employer-provided group medical benefits (8%), privately purchased insurance (5%), and other private sources (1%). Of the $67,807 million total health expenditure in 2004/05, current expenditure comprised $65,429 million (96%) while $2378 million (4%) were capital expenses (ie investment in medical facilities). Services of curative care accounted for the largest share of total health spending (67%) which were made up of ambulatory services (35%), in-patient curative care (28%), day patient hospital services (3%), and home care (1%). The next largest share of total health expenditure was spent on medical goods outside the patient care setting (10%). Analysed by health care provider, hospitals accounted for the largest share (46%) and providers of ambulatory health care the second largest share (30%) of total health spending in 2004/05. We observed a system-wide trend towards service consolidation at institutions (as opposed to free-standing ambulatory clinics, most of which are staffed by solo practitioner). In 2004/05, public expenditure on health amounted to $35,247 million (53.9% of total current expenditure), which was mostly incurred at hospitals (76.5%), whilst private expenditure ($30,182 million) was mostly incurred at providers of ambulatory health care (54.6%). This reflects the mixed health care economy of Hong Kong where public hospitals generally account for about 90% of total bed-days and private doctors (including Western and Chinese medicine practitioners) provide 75% to 80% of out-patient care. While both public and private spending were mostly expended on personal health care services and goods (92.9%), the distributional patterns among functional categories differed. Public expenditure was targeted at in-patient care (54.2%) and substantially less on out-patient care (24.5%), especially low-intensity first-contact care. In comparison, private spending was mostly concentrated on out-patient care (49.6%), whereas medical goods outside the patient care setting (22.6%) and in-patient care (18.8%) comprised the majority of the remaining share. Compared to OECD countries, Hong Kong has devoted a relatively low percentage of gross domestic product to health in the last decade. As a share of total spending, public funding (either general government revenue or social security funds) was also lower than in most comparably developed economies, although commensurate with its public revenue collection base.

Clinical and economic impact of an antibiotics stewardship programme in a regional hospital in Hong Kong.

BACKGROUND: Inappropriate use of antibiotics is one of the important factors attributing to emergence of drug-resistant pathogens. Infection with multidrug-resistant pathogens adversely affects quality of medical care. CONTEXT: Queen Elizabeth Hospital, an 1800-bed acute service hospital in Hong Kong. Antibiotics are commonly prescribed for treating acute infections. KEY MEASURES FOR IMPROVEMENT: Reduce inappropriate prescription of broad-spectrum antibiotics and overall antibiotic prescription through implementation of a multidisciplinary antibiotics stewardship programme (ASP). STRATEGIES FOR CHANGE: A multidisciplinary programme involving policy and guideline formulation, education and feedback, monthly antibiotic consumption and cost monitoring, antimicrobial susceptibility pattern reporting and concurrent feedbacks for commonly prescribed broad-spectrum antibiotics was implemented in 2004. Predefined logistics to prescribe "restricted" antibiotics were formulated and implemented with collaborative efforts from clinical and non-clinical departments. The programme was supported by management at department and hospital levels. EFFECTS OF CHANGE: Broad-spectrum antibiotics were prescribed inappropriately in 28.9% (n = 192) clinical scenarios. The ASP reduced the restricted and total antibiotic consumption as well as the antibiotics-related costs. Predefined clinical outcomes were not adversely affected. Economic analysis suggested that the extra human cost in running ASP could be offset by savings from antibiotic expenditure. LESSONS LEARNED: It is cost-effective to implement a multidisciplinary ASP in acute service hospitals as the programme reduces antibiotic consumption and results in overall cost savings. The quality of medical care is not jeopardized as the important clinical outcomes are not adversely affected. The generalisability and sustainability of ASPs in other clinical contexts warrant further studies to ensure the continuous success of this programme.

Are height and leg length universal markers of childhood conditions? The Guangzhou Biobank cohort study.

OBJECTIVE: In developed western populations longer legs have been shown to be a marker of better early childhood conditions. In the first generations to experience the epidemiologic transition and associated economic development, epigenetic constraints on growth might preclude improved childhood conditions from increasing leg growth or height. DESIGN, SETTING AND PARTICIPANTS: Multivariable linear regression was used to assess the association of parental growth environment, proxied by parental literacy, and childhood conditions, proxied by parental possessions, with leg length, sitting height and height in a cross-sectional sample from 2005-6 of 9998 Chinese people aged at least 50 years from phase 2 of the Guangzhou Biobank Cohort Study. MAIN RESULTS: Adjusted for age and sex, the association of childhood conditions with leg length and height varied with parental literacy (interaction p values <0.01 and 0.03), but not for sitting height (p value 0.43), with statistically significant trends (p values <0.01) for parental possessions to be associated with longer legs and greater height only in the offspring of two literate parents where legs were longer by 0.56 cm (95% CI 0.27 to 0.86) and height greater by 1.16 cm (95% CI 0.74 to 1.58) for participants with most, compared with least, parental possessions in childhood. CONCLUSIONS: Epigenetic influences originating in earlier generations may constrain growth during the infancy and/or childhood phases in very recently developed populations. Neither height nor leg length should be assumed to be consistent proxies of early life environment with corresponding implications for economic history, the aetiology of some chronic diseases and the monitoring of population health.

Is leg length a biomarker of childhood conditions in older Chinese women? The Guangzhou Biobank Cohort Study.

OBJECTIVE: In developed western populations longer legs have been shown to be a biomarker of better early childhood conditions. It was hypothesised that in transitioning populations better childhood conditions may bring forward puberty and thus decrease leg length, counteracting the overall positive effect of a favourable childhood environment on leg growth. DESIGN: Structural equation modelling was used to assess the interrelationship of age, education, father's job, age of menarche and leg length in a cross-sectional sample of 7273 Chinese women aged at least 50 years from the Guangzhou Biobank Cohort Study. RESULTS: Leg length had no significant association with education or father's occupation on bivariable testing. After including age of menarche in the model, education was associated with longer legs (0.45 cm longer per 10 years of education, 95% CI 0.20 to 0.71). Education was also associated with younger age of menarche (1.21 years younger per 10 years of education, 95% CI 1.09 to 1.34), which was in turn associated with shorter legs (0.23 cm shorter per year of menarche earlier, 95% CI 0.18 to 0.27). CONCLUSIONS: In older Chinese women leg length is not a universal biomarker of childhood conditions, when proxied by her educational level and father's occupation. Nutritionally driven epigenetic influences operating over generations may constrain growth in very recently developed populations. Given the impact of childhood conditions on health, and the dearth of long-term records outside the industrialised world, a greater understanding of the influences on growth in the developing world is required.