Dramatic escalation in metabolic syndrome and cardiovascular risk in a Chinese population experiencing rapid economic development.

BACKGROUND: Metabolic syndrome (MetSyn) increases the incidence of cardiovascular disease. Information on changes in prevalence of MetSyn in developing countries is limited. This study aims to compare MetSyn prevalence and its associated vascular risk over the period between 2002 and 2010 in a population which has had the world's fastest economic development over the past three decades. METHODS: Two health surveys were conducted by using the multistage cluster random sampling method in a Chinese population of 85 million in southern China. The participants received a full medical check-up, including measurement of blood pressure (BP), obesity indices, fasting lipids and glucose levels. Data describing socio-economic status and lifestyle factors were also collected through interview. Metabolic syndrome was defined in accordance with the International Diabetes Federation criteria. RESULTS: A total of 3,561 participants from Survey 2010 were included in the data analysis. Women had a significantly higher prevalence of MetSyn than men. Comparison between the two surveys shows that age-standardized prevalence of MetSyn increased fourfold (from 5.4% in 2002 to 21.3% in 2010) in those ≧ 20 years. Among the MetSyn components, prevalence of hyperglycaemia has increased most (from 9.1% to 53.1%). The age-standardized prevalence of central obesity, hypertension, hypertriglyceridaemia and low HDL-cholesterol increased from 13.5% to 25.4%, from 23.6% to 40.8%, from 12.1% to 17.4% and from 32.1% to 71.1%, respectively. Differences between rural and urban residents in the prevalence in MetSyn and its components narrowed in 2010. CONCLUSIONS: Cardiovascular risk escalated dramatically in this population between 2002 and 2010. The escalation may relate to the rapid economic development, which led to accelerating changes in nutrition, lifestyle, and socio-economic status. Our findings suggest that health transition in rapidly developing second- and third-world countries may be much faster than what has been observed in Western countries.

Hypertension prevalence, awareness, treatment, control and associated factors in a developing southern Chinese population: analysis of serial cross-sectional health survey data 2002-2010.

BACKGROUND: The aim of this study was to investigate trends in the distribution, prevalence, awareness, treatment, and control of hypertension in a Chinese population that has had the fastest growing gross domestic product in the world over the past 3 decades. METHODS: Four standardized cross-sectional health surveys were conducted between 2002 and 2010 in a population consisting of 85 million residents in Guangdong Province. Multistage cluster sampling was adopted to recruit representative samples. The data were obtained through on-site health examinations and face-to-face interviews. RESULTS: The aging trend in this population was not significant (P = 0.17) during the survey period, whereas body mass index/waist circumference increased significantly (P = 0.047 for body mass index and P < 0.001 for waist circumference). The age-standardized prevalence of hypertension increased from 10.5% to 13.3%, averaging a 0.35% increase per year. A higher risk was observed in younger residents over the survey period. Awareness and treatment increased by 22.0% and 19.0%, respectively, in the rural areas, whereas there was no significant change in the urban area (the corresponding figures were 1.8% and -3.1%, respectively). There was no improvement in hypertension control (the age-standardized control prevalence in 2002 was 50.3%, whereas it was 43.2% in 2010). CONCLUSIONS: The prevalence of hypertension increased slightly in this population with the fastest economic development. This increase mirrored the trend of increasing obesity. Awareness and treatment of hypertension have improved in the rural areas, although there were no significant changes in the urban areas. The prevalence of awareness and treatment remains at unacceptably low levels, suggesting that urgent and aggressive strategies are necessary to improve hypertension control and intervention.

Diabetes and pre-diabetes as determined by glycated haemoglobin A1c and glucose levels in a developing southern Chinese population.

BACKGROUND: The American Diabetes Association and World Health Organization have recently adopted the HbA1c measurement as one method of diagnostic criteria for diabetes. The change in diagnostic criteria has important implications for diabetes treatment and prevention. We therefore investigate diabetes using HbA1c and glucose criteria together, and assess the prevalent trend in a developing southern Chinese population with 85 million residents. METHODS: A stratified multistage random sampling method was applied and a representative sample of 3590 residents 18 years of age or above was obtained in 2010. Each participant received a full medical check-up, including measurement of fasting plasma glucose, 2-hour post-load plasma glucose, and HbA1c. Information on history of diagnosis and treatment of diabetes was collected. The prevalence of diabetes obtained from the present survey was compared with the data from the survey in 2002. RESULTS: The prevalence of diabetes based on both glucose and HbA1c measurements was 21.7% (95% CI: 17.4%-26.1%) in 2010, which suggests that more than 1 in 5 adult residents were suffering from diabetes in this developing population. Only 12.9% (95% CI: 8.3%-17.6%) of diabetic residents were aware of their condition. The prevalence of pre-diabetes was 66.3% (95% CI: 62.7%-69.8%). The prevalence of diabetes and pre-diabetes which met all the three diagnostic thresholds (fast plasma glucose, 2 hour post-load plasma glucose, and HbA1c) was 3.1% and 5.2%, respectively. Diabetes and pre-diabetes as determined by HbA1c measurement had higher vascular risk than those determined by glucose levels. The prevalence of diabetes increased from 2.9% (95% CI: 2.0%-3.7%) in 2002 to 13.8% (95% CI: 10.2%-17.3%) in 2010 based on the same glucose criteria. CONCLUSIONS: Our results show that the diabetes epidemic is accelerating in China. The awareness of diabetes is extremely low. The glucose test and HbA1c measurement should be used together to increase detection of diabetes and pre-diabetes.

[What temperature index is the best predictor for the impact of temperature on mortality].

OBJECTIVE: To explore the suitable temperature index to establish temperature-mortality model. METHODS: The mortality and meteorological information of Guangzhou between year 2006 and 2010 were collected to explore the association between sendible temperature, heat index and deaths by adopting distributed lag non-linear model to fit the daily maximum, mean and minimum temperature with and without humidity. Q-Q plots based on the standardized residuals of each model were used to qualitatively access the goodness of fitting. The minimum Akaike information criterion (AIC) and residual sum of squares (RSS) value were used to explore the most suitable temperature index for model establishment, and to further analyze the fittest temperature index for different diseases, ages and cold and hot effect. RESULTS: Guangzhou features a subtropical monsoon climate, with an annual average temperature at 22.9°C and daily average relative humidity of 71%. The standardized residuals of all models followed normal distribution. For all death, death from circulation system diseases, the 65-84 years old aging groups and cold effect models, the daily average temperature fit better, whose AIC (RSS) values were the smallest as 11 537 (1897), 9527 (1928), 10 595 (2018) and 11 523 (1899), respectively. However, for death from respiratory system disease, groups aging under 65 years old or over 85 years old and hot effect models, the daily average sendible temperature fit better, whose AIC (RSS) values were the smallest as 8265(1854), 675 (1739), 8550 (1871) and 11 687 (1938), respectively. In comparison with the model controlling both temperature and relative humidity, different diseases, aging groups and cold and hot effect models fitted by sendible temperature index showed smaller AIC (RSS) values. The relative risk (RR) value of the cold effect lagging 0 - 3 days fitting by daily maximal temperature was < 1, and the RR value of it fitting by daily minimum temperature was > 1.04. The RR value of the hot effect lagging 0 - 1 days fitting by daily maximal temperature was < 1.16, and the RR values of it fitting by daily minimum temperature and daily average temperature were > 1.16. CONCLUSION: There were no best temperature indicators for different diseases, ages and cold and hot effect. The model using sendible temperature index better fit the model including relative humidity as a covariable.

[Association between temperature and daily mortality in Guangzhou, 2006-2009: a time-series study].

OBJECTIVE: To study the association between temperature and daily mortality from June 1, 2006 to December 31, 2009 in Guangzhou. METHODS: Time series approach was used to estimate the impact of temperature on the rates of total and cause-specific daily mortality. We fitted generalized additive Poisson regression using non-parametric smooth functions to control for the long-term time trend, day of week, air pollution and other weather variables. RESULTS: A slight sloping U-like relationship between the total mortality and temperature was found, with an optimum average temperature (temperature with lowest mortality risk) value of 19.7°C in Guangzhou. For temperature above the optimum value, the relative risk of total mortality increased by 3.0% (RR=1.030, 95%CI: 1.011-1.050) for each increase of degree in Celsius. For average temperature below the optimum value, the relative risk of total mortality and diseases of circulatory system had a 3.3% (RR=0.967, 95%CI: 0.936-0.997) decrease and a 3.6% (RR=0.964, 95%CI: 0.935-0.994) increase, for each degree of Celsius increase, respectively. CONCLUSION: Our findings showed that the temperature had an impact on the daily mortality in Guangzhou. Countermeasures needed to be taken to reduce the temperature related mortality.

[Features on suicide attempts and its influencing factors among residents in Guangdong province].

OBJECTIVE: To understand the prevalence of suicide attempts and its related risk factors in Guangdong province to provide scientific basis information for suicide intervention. METHODS: Multi-stage stratified random sampling method was used to select the sample. 42 streets or towns were selected from 21 counties or districts through randomly sampling. 4 communities were then chosen from every selected town or district, followed by 40 families chosen from every village or community. Questionnaire was used to collect data on suicide attempts and its related risk factors. SPSS 16.0 was used for data analysis. RESULTS: 6625 peoples were participated in the study. The 12-month incidence of suicidal attempts was 0.8%. It was higher for females (1.1%) than that for males (0.5%), and the 25 - 35 years (1.6%) age group was among the highest. There was no significant difference between the prevalence rates in urban or rural residents. RESULTS: from multivariate analysis showed that factors as: being female (OR = 2.1), experienced negative events of life (OR = 15.5), in poor sleeping condition (OR = 1.6), feeling lonely (OR = 1.5) and anxiety (OR = 1.8) were high risk for suicide attempts. CONCLUSION: Suicide attempts in Guangdong province exhibited a high prevalence with complicated influencing factors. Comprehensive countermeasures are needed to prevent and reduce suicidal behaviors.

[Study on health-related behaviors among males in rural and urban residents from Guangdong province].

OBJECTIVE: To compare the magnitude of inequities in health-related behaviors among males in Guangdong province, and to investigate the extent of the disparities. METHODS: Data sets available from the Guangdong Chronic Diseases and Risk Factors Survey 2007 are used. Concentration index (C) and concentration curve are employed to measure the differential of males' health-related behaviors across urban and rural areas in Guangdong. Odds ratios of 6 health-related behaviors among different areas are derived from 4 logistic models, after adjusting for age, married state, educational status, occupation and income. RESULTS: Results from Cs reveal that the inequality gradients disadvantageous to men in rural areas are:smoking (C = -0.075, P = 0.000), alcohol intake (C = -0.023, P = 0.002), blood pressure (C = 0.106, P = 0.000), blood sugar (C = 0.114, P = 0.000) and weight (C = 0.107, P = 0.000), while lack of physical activity (C = 0.044, P = 0.000)concentrates in the more affluent areas. The magnitudes of these inequalities appear to be higher on health-seeking behaviors than on health-risk behaviors. After adjusting for age and marital status, there is still strong evidence showing the rural-urban differences in the health related behaviors among males in Guangdong province. When educational status, occupation and income are added to the logistic model as control factors, the results have led to a loss of statistical significance on such rural-urban inequalities, indicating that socioeconomic factors play an important role on these health-related behaviors which leads to the inequalities among males in Guangdong province. CONCLUSION: To reduce the gaps in health-related behaviors seen in the rural and urban areas, effective policies should be developed to change the social determinants of rural-urban differences in health and to strengthen the implementation of health-related programs on those vulnerable groups.