Loneliness shapes disparities in healthy life expectancy: a multi-state analysis from China.

OBJECTIVES: To assess the influence of loneliness on the healthy life expectancy of older adults in China and its gender disparities across different health indicators, in order to provide insights for enhancing the health status and subjective well-being of the older population. METHOD: We conducted a cohort analysis using four waves of weighted samples (2008, 2011, 2014, and 2018) from the Chinese Longitudinal Healthy Longevity Survey, encompassing 15,507 respondents aged 65-99. Physical and subjective health were assessed through activity of daily living (ADL) and self-rated health (SRH), respectively. Utilizing loneliness status as a time-variant variable, we employed the multi-state interpolated Markov Chain to explore the associations between loneliness and age-specific life expectancy (LE), healthy life expectancy (HLE), and the proportion of healthy life expectancy in life expectancy (HLE/LE). RESULTS: Compared to the non-lonely population, both LE and HLE were lower among lonely individuals. Regarding gender differences, the HLE/LE for females in the lonely population was consistently lower than that for males. The impact of loneliness on the health of older adults varied by measurement indicators and gender. Specifically, based on ADL results, the decline in HLE/LE was greater for females, with a decline of 53.6% for lonely females compared to 51.7% for non-lonely females between the ages of 65 and 99. For males, the decline was 51.4% for lonely males and 51.5% for non-lonely males. According to SRH, the gender difference in the decline of HLE/LE due to loneliness was less apparent. For males, the change in HLE/LE for non-lonely individuals was 3.4%, compared to 4.2% for lonely individuals, whereas for females, the change was 3.7% for non-lonely individuals and 4.4% for lonely individuals. CONCLUSION: Loneliness exerts varied effects on health across different measurement indicators and gender demographics. Targeted health promotion interventions are imperative to mitigate these negative impacts, particularly emphasizing the enhancement of subjective well-being and physical functioning, especially among older adult females.

Association between short-term daily temperature variability and blood pressure in the Chinese population: From the China hypertension survey.

BACKGROUND: We aimed to evaluate the impacts of short-term daily temperature variability (DTV) on blood pressure (BP) among participants with normotension, prehypertension, and hypertension, respectively, and explore the effects in different climate zones and seasons. METHODS: A representative population sample (n = 397,173) covering the subtropical, temperate continental, and temperate monsoon zones was obtained from the China Hypertension Survey. DTV was calculated as the standard deviation of daily minimum and maximum temperatures during the exposure days. The linear mixed effect regression model was used to estimate the associations between DTV exposure and BP among normotension, prehypertension, and hypertension, respectively, and further stratified analysis was performed by climate zones and seasons. RESULTS: After adjustment for confounders, per interquartile range (IQR) increase in DTV (2.28 °C) at 0-6 days of exposure was associated with an increase of 0.41 mmHg (95 % confidence interval [CI]: 0.07, 0.75) in systolic BP (SBP) and 0.41 mmHg (95 % CI: 0.09, 0.72) in pulse pressure (PP) among hypertensive participants in the subtropical zone. Similarly, DTV exposure was associated with an increase of 0.31 mmHg (95 % CI: 0.06, 0.55) in SBP and 0.59 mmHg (95 % CI: 0.24, 0.94) in PP among prehypertensive participants in the temperate continental zone. Additionally, during the warm season, DTV was positively associated with SBP among populations with prehypertension and hypertension, and with PP among all three populations. CONCLUSION: Short-term DTV exposure was associated with an increase in SBP and PP among hypertensive and prehypertensive participants in the subtropical zone and the temperate continental zone. In addition, positive associations of DTV with SBP and PP were observed among participants with prehypertension and hypertension in the warm season. Comprehensive health education and effective intervention strategies should be implemented to mitigate the effects of temperature variations on BP, particularly among prehypertensive and hypertensive populations.

Impact of income inequalities on subjective perception of older adult health: An analysis of healthy life expectancy in China from 1997 to 2006.

AIM: Driven by rapid socioeconomic development over recent decades, there are widening income inequalities and subjective health disparities among older adults in China. This study explored the relationship between income inequalities and self-rated healthy life expectancy (HLE) considering potential sex-specific differences. METHODS: From a cohort of 1760 individuals aged ≥60 years from the China Health and Nutrition Survey (1997-2006), we calculated age-specific life expectancy (LE), HLE and the proportion of HLE to LE (HLE/LE) by sex using the IMaCh software, incorporated time-varying income levels of older adults. RESULTS: Although longevity has significantly improved, the well-being of Chinese older adults could be further enhanced by assessing HLE, as the results showed that at age 60 years, ~20% of their LE was characterized by unhealthiness. Discriminated by economic status, lower-income individuals experienced worse self-rated health compared with the general population and affluent counterparts. For instance, at age 60 years, the LE, HLE and HLE/LE of low-income men were 19.8 (95% CI 18.4-21.1), 16.2 years (95% CI 15.0-17.5) and 81.8%, respectively, lower than their general (21.7, 95% CI: 20.4-23.0; 18.0, 95% CI 16.8-19.2; and 82.9%) and high-income counterparts (25.1, 95% CI 23.1-27.2; 21.4, 95% CI 19.5-23.3; and 85.3%). Sex disparities were noticeable among low-income individuals in HLE/LE, with low-income women showing the most significant disadvantage. CONCLUSIONS: Income inequalities exacerbated subjective health disparities among older adults, particularly among lower-income individuals and women. Our findings carry significant implications for formulating public health and social welfare strategies, especially in nations grappling with an aging population and undergoing parallel socioeconomic development. Geriatr Gerontol Int 2024; 24: 109-115.

Parental and Social Factors' Contribution to Adverse Pregnancy Outcomes with Urban-Rural Disparities - Four Provinces, China, 2011-2020.

What is already known about this topic?: The prevalence of adverse pregnancy outcomes (APOs) exhibits a disparity between urban and rural areas, which is commonly associated with various factors, such as demographic and socio-environmental factors. However, the specific contribution of each factor has not yet been elucidated. What is added by this report?: This study demonstrates that the primary factors contributing to urban-rural differences in the prevalence of APOs are population structure, parental age, parity, and regional development. What are the implications for public health practice?: Future prevention and control measures should be directed toward considering population structure and regional differences. Accurate interventions will enhance the efficiency of public health services.

Association between maternal exposure to chemical fertilizer and the risk of birth defects in a rural population in northern China: a population-based study.

BACKGROUND: Maternal exposure to pesticides during early pregnancy is associated with increased risks of birth defects, while the association between maternal exposure to chemical fertilizer during pregnancy and the risk of birth defects remains unknown. METHODS: Data were from a population-based birth defects surveillance system between 2007 and 2012 in Pingding County, Shanxi Province, northern China. A total of 14 074 births with 235 birth defects were used to estimate spatial clustering and correlations at the village level. A population-based case-control study of 157 cases with birth defects and 204 controls was performed to investigate the association between maternal chemical fertilizer exposure and the risk of birth defects by a two-level logistic model. RESULTS: The total prevalence of birth defects between 2007 and 2012 was 167.0/10 000 births. The spatial analysis indicated a remarkable high-risk area of birth defects in the southeast of Pingding County and the use of chemical fertilizer was associated with the risk of birth defects at the village level. After adjusting for confounders at the individual level, mothers who live in villages with chemical fertilizer application ≥65 tons/y had an increased risk of birth defects (adjusted odds ratio 2.06 [95% confidence interval 1.23 to 3.46]) compared with those of <65 tons/y. CONCLUSIONS: Our findings suggest that the risk of birth defects may be associated with the use of chemical fertilizer in rural northern China. The findings must be cautiously interpreted and need to be investigated on larger samples.

Interactive effects of maternal exposure to chemical fertilizer and socio-economic status on the risk of low birth weight.

BACKGROUND: Maternal exposure to chemical fertilizer and disadvantaged maternal socio-economic status (SES) have been found to associate with increased risk of low birth weight (LBW). However, whether the two factors would interact to elevate the risk of LBW remains unknown. The present study aimed to explore the interactive effects of maternal exposure to chemical fertilizer during pregnancy and low SES on the risk of term LBW (tLBW). METHODS: In this population-based case-control study, 179 tLBW cases (birthweight < 2500 g and gestational age ≥ 37 weeks) and 204 controls (birthweight ≥ 2500 g and gestational age ≥ 37 weeks) were chosen from the Perinatal Health Care Surveillance System of Pingding County, Shanxi Province, China between 2007 and 2012. Data on basic socio-demographic, dietary and lifestyle characteristics and environmental exposure were directly extracted from the system. Maternal exposure to chemical fertilizer was measured at both household level and village level. Household-level exposure was indicated by household chemical fertilizer use in farming during pregnancy and the data was collected by trained healthcare workers after the selection of cases and controls in 2013. Village-level exposure was indicated by annual amount of village chemical fertilizer consumption per acre and the data came from the Annals of National Economics Statistics of Pingding County in 2010. Interactions between maternal exposure to chemical fertilizer and SES were assessed in logistic regressions using relative excess risk due to interaction (RERI), which indicates an additive interaction if larger than 0. RESULTS: The combination of low maternal SES and high exposure to village-level chemical fertilizer consumption was associated with increased risk of tLBW (aOR = 2.62, 95%CI: 1.44 ~ 4.77); The combination of low maternal SES and exposure to household chemical fertilizer use was associated with elevated risk of tLBW (aOR = 2.18, 95%CI: 1.24 ~ 3.83). Additive interactions were detected between high exposure to village-level chemical fertilizer consumption and low maternal SES (RERI:1.79, P < 0.001) and between exposure to household chemical fertilizer use and low maternal SES (RERI:0.77, P < 0.05). CONCLUSIONS: Our study suggested negative impacts of potential agricultural pollutants on adverse pregnancy outcomes, especially in disadvantaged socio-economic populations.

Spatial variation and association between maternal chemical fertilizer exposure and preterm birth in a rural area in Northern China.

Whether maternal macro-environmental chemical fertilizer exposure has an association with the risk of preterm birth remains unclear. This study aimed to investigate the association between maternal exposure to chemical fertilizer during pregnancy and the risk of preterm birth. A total of 13,861 births, including 402 preterm birth from 313 villages in Pingding County, Shanxi Province, China, were analyzed to explore spatial variations of preterm birth risks at the village level. Spatial variations of preterm birth were visualized and tested with Disease Mapping, Moran's I and G* Statistic. The spatial zero-inflated negative binomial model was used to evaluate the incidence rate ratio (IRR) of preterm birth in different chemical fertilizer consumption levels at the village level. A population-based case-control study was conducted including 153 preterm births cases and 204 controls at the household level. The two-level logistic regression model was performed to estimate the association between risks of preterm birth and maternal exposure to chemical fertilizer after adjusting confounding factors. The findings indicated a remarkably clustering effect in relative risks of preterm birth and identified a high-risk clustering region of preterm birth from the south-central to the southwest and a low-risk clustering region in the northern Pingding county. The results of the spatial zero-inflated negative binomial model showed that the risk of preterm birth in the villages with chemical fertilizer consumption≥100 tons was 2.82 (95% CI: 1.50-5.57) times higher than those with <50 tons. Maternal exposure to chemical fertilizer ≥100 tons at village level was associated with an increased risk of preterm birth (aOR 2.14, 95%CI: 1.18-3.96), compared with exposure <50 tons after adjusting for confounding variables. The findings suggests that chemical fertilizers deserve more attention as a potential risk factor of preterm birth.

Hypertension Prevalence Rates Among Urban and Rural Older Adults of China, 1991-2015: A Standardization and Decomposition Analysis.

Objectives: The prevalence of hypertension (HTN) among older adults is becoming an important issue in public health in China as it is now stepping into the super-aged society with high pressure of a chronic disease burden. With urban-rural differences in population composition and health facilities, this study aimed to assess the gaps in the prevalence trends of HTN among older adults by considering demographic factors such as age, gender, education level, and regional differences during 1991-2015 in China. Methods: We adopted the consistent sampling design and measure of HTN of the cross-longitudinal surveys of the China Health and Nutrition survey, and we compared the HTN prevalence rates between urban and rural older adults by taking each wave of the survey as a cross-sectional sample of the Chinese population by the following and supplementary samples. The classic standardization and decomposition analysis method was utilized with four factor-specific rates, and contributions were calculated, i.e., age, gender, education, and region, which reflects the aspect of demographic and social development differences between urban and rural areas of China. Results: The prevalence rates of HTN of the whole of older adults were increasing in 1991-2015. However, the gaps of prevalence rates of HTN between urban and rural areas show different trends accompanied by the health policies launched by the government. Namely, the gap was narrowed during 1993-1997 and then enlarged during 1997-2011 and narrowing again. Those trends reflect the policy effects with the health resource allocation and utilization of health services for urban and rural older adults. Conclusions: With the four factors of decomposition analysis, the differences reflect the results of health policy effects, considering the urban-rural discrepancy on older adults with different demographic characteristics. Hence, the differentiated policies should be considered with the urban-rural population, such as HTN prevention and the population health promotion.

Trends of Adverse Pregnancy Outcomes in a High Prevalence Region of Birth Defects - Shanxi Province, China, 2007-2019.

What is already known about this topic? Shanxi Province in northern China has been identified as a region with the highest prevalence of birth defects nationwide. With large amounts of financial support devoted for prevention and related interventions for birth defects, huge progress has been made as a 60% decrease in its prevalence was observed from 2009 to 2014. What is added by this report? The study presented a recent trend of adverse pregnancy outcomes (APOs) in Shanxi Province, a region with high prevalence of birth defects in China from 2007-2019. The prevalence of serious APOs including birth defects, stillbirths, and neonatal deaths remained at a relatively low level, yet macrosomia, low birth weight (LBW), preterm births, and spontaneous abortion comprised a majority of all APOs, with macrosomia showing an obvious upward trend from 2007 to 2012. What are the implications for public health practice? These findings provide new evidence for prevention and intervention strategies of APOs in northern China. Future research should focus on comprehensive interventions for multiple APOs, especially macrosomia, LBW, preterm births, and spontaneous abortion.

[Association between vitamin D deficiency and Toxoplasma gondii infection in women of childbearing age].

OBJECTIVE: To explore the association between the risk of vitamin D deficiency and the infection of Toxoplasma gondii in women of childbearing age. METHODS: Based on a Women's Reproductive Health Cohort Study performed from 2007 to 2010 in four counties of Henan Province, Toxoplasma gondii infection were tested by enzyme linked immunosorbent assay(ELISA). A total of 1151 women with pregnancy outcomes were followed up and pre-pregnancy vitamin D level was measured with serum samples. Case-control study was used to examine the association between the risk of vitamin D deficiency and Toxoplasma infection. RESULTS: The prevalence of vitamin D deficiency was 61. 5%(95% CI 59. 2%-64. 9%) and Toxoplasma infection was 9. 6%(95% CI 7. 9%-11. 4%), among which IgG positive, IgM positive and both positive were 7. 6%, 2. 3% and 0. 3%, respectively. After adjusting confounding factors, including education, family annual income, and dietary intake frequencies. , it was found that the risk of vitamin D deficiency in women infected with Toxoplasma gondii recently or previously was 1. 75 times higher than that of uninfected women(95% CI 1. 11-2. 77). CONCLUSION: There is association between the risk of vitamin D deficiency and the infection of Toxoplasma gondii in women of childbearing age.

Geographic variations and potential macro-environmental exposure of hypertension: from the China hypertension survey.

OBJECTIVES: The study aimed to investigate the spatial variation of hypertension (HTN) and the associations between the risk of HTN and altitude, longitude, latitude in Chinese population. METHODS: The newest China Hypertension Survey (CHS) study, which used a nationally representative sample, was conducted between 2012 and 2015. A total of 451 755 participants aged at least 18 years from 262 county-level regions in 31 provinces were analyzed to explore the geographical variations of HTN prevalence at county-level. A total of 444 375 participants were included in two-level logistic regression model to examine the association between HTN risk and exposure to altitude, longitude, and latitude after adjusting for potential confounding variables at individual level. RESULTS: The findings of spatial analysis indicated that there were remarkably high and low HTN prevalence zones. High HTN prevalence zones extended from parts of the southeast to northern China and the northeast. The risk of HTN increased with increasing longitude, with adjusted odds ratios (aORs, 95% confidence interval [CI]) of 2.08 (1.04--4.18), 2.21 (1.15--4.22), 2.54 (1.31--4.93), 2.59 (1.32--5.08), and 2.81 (1.12--7.08) for longitudes of 90-100°E, 100-110°E, 110-120°E, 120-130°E, and at least 130°E, respectively, with a significant dose--response relationship that HTN risks increase as longitude rises from 90°E to ≥130°E(Ptrend <0.001), compared with the longitude group of less than 80°E, consistent with the conclusion that geographical variations of high HTN prevalence zones by spatial analysis. CONCLUSION: The findings of remarkably high HTN prevalence zones modified previous understandings about the regional difference of HTN distribution, and provide an important basis for future efforts to prevent and control HTN in different regions of China.

Effect of periconceptional folic acid supplementation on the risk of neural tube defects associated with a previous spontaneous abortion or maternal first-trimester fever.

STUDY QUESTION: Does maternal periconceptional no folic acid supplementation have an increased risk of neural tube defects (NTDs) associated with previous spontaneous abortion or first-trimester fever? SUMMARY ANSWER: Maternal periconceptional no folic acid supplementation can increase the risk of NTDs associated with previous spontaneous abortion or first-trimester fever, independent of known confounding factors. WHAT IS KNOWN ALREADY: Maternal periconceptional folic acid deficiency can increase the risk of NTDs. However, whether an interaction between periconceptional no folic acid supplementation and history of spontaneous abortion or first-trimester fever may have an increased risk of NTDs remains unknown. STUDY DESIGN, SIZE, DURATION: A population-based case-control study was performed including 104 nuclear families with offspring with NTDs and 100 control families with normal offspring between 1993 and 2002. PARTICIPANTS/MATERIALS, SETTING, METHODS: We investigated the potential interaction between periconceptional no folic acid use and a maternal history of spontaneous abortion or first-trimester fever in the risk for NTDs. Information on exposure factors was obtained at the onset of pregnancy, and pregnancy outcomes were collected during the first week after delivery or at the time of termination of the pregnancy. A multivariate logistic regression analysis was performed. MAIN RESULTS AND THE ROLE OF CHANCE: The interaction between periconceptional no folic acid use and a maternal history of spontaneous abortion markedly increased the risk of NTDs (adjusted odds ratio (aOR) 18.68, 95% CI, 4.43-78.76) after adjusting for potential confounding factors. The interaction coefficient was found to be 2.08, higher than 1, indicating that there is a significant interaction between two factors. Mothers who did not take periconceptional folic acid and had first-trimester fever had an increased risk of NTDs (aOR 21.81, 95% CI, 8.81-80.73). However, the interaction coefficient was found to be 0.62, less than 1, indicating that there is no significant interaction between two factors. LIMITATIONS, REASONS FOR CAUTION: A potential limitation was that the interval between the previous spontaneous abortion and the beginning of the subsequent pregnancy could not be estimated accurately, but was at least 1 year or more. WIDER IMPLICATIONS OF THE FINDINGS: We emphasize that a previous spontaneous abortion may represent a first occurrence of NTDs rather than be the cause of NTDs. Our findings indicate that mothers with a history of spontaneous abortion are ideal candidates for periconceptional folic acid supplementation. STUDY FUNDING/COMPETING INTEREST(S): This work was supported by National Natural Science Foundation of China (41871360) and Danone Nutrition Center for Dietary Nutrition Research and Education Foundation (DIC2015-05). There are no competing interests to declare.

Generational differences in longitudinal blood pressure trajectories by geographic region during socioeconomic transitions in China.

OBJECTIVES: To examine generational differences in longitudinal blood pressure trajectories by region following socioeconomic transitions, which is important for establishing the population risk of cardiovascular diseases (CVDs). METHODS: With data from the China Health and Nutrition Survey (1991-2011), we used multilevel growth-curve models to estimate systolic/diastolic blood pressure (SBP/DBP) levels at the mean age and rates of change by cohort (born between 1931 and 1980), region, and sex. RESULTS: Younger cohorts generally had higher SBP/DBP levels at 44.5 years but lower growth rates in SBP/DBP than older cohorts. They became prehypertensive (SBP ≥ 120 mm Hg or DBP ≥ 80 mm Hg) at an earlier age. The upward shift of SBP/DBP trajectories across cohorts was more pronounced in the Coastal and Southern Mountainous Regions than the Northeastern and Inland Regions, and for males versus females. CONCLUSIONS: Younger cohorts have a longer lifetime duration of being susceptible to CVDs, posing warnings for an increased burden of CVDs. Generational differences in BP trajectories and geographic and sex variations in the cohort trends highlight the need for tailored interventions to tackle the generation, region, and sex-based risk of CVDs.

Periconceptional Multivitamin Supplementation Containing Folic Acid and Sex Ratio at Birth in a Chinese Population: a Prospective Cohort Study.

BACKGROUND: To determine whether periconceptional use of multivitamin supplements containing folic acid increases the occurrence of male births in a Chinese population. METHODS: A prospective cohort study was carried out in 18 counties in four provinces of China. Participants were naturally and voluntarily divided into an intervention group (who took a multivitamin pill containing folic acid, n = 25,418) and a control group (who did not take any multivitamin, n = 26,580). Multivitamin supplements containing folic acid was ascertained before pregnancy. Pregnant women were followed through the first trimester of pregnancy and the outcome of pregnancy (i.e. livebirth, stillbirth, or fetal death; sex at birth) was recorded. RESULTS: A total of 52,043 pregnancies and 51,998 births were recorded between September 2000 and August 2002. The proportion of males born to women who did and did not take the multivitamin were 54.8% (n = 13,935) and 54.0% (n = 11,483), respectively. The male to female sex ratios at birth among women who did and did not take the multivitamin were 117:100 and 121:100, respectively. The risk ratio was 1.03 [95% confidence interval 0.99, 1.06] after adjusting for confounding factors. CONCLUSIONS: These findings suggest that periconceptional multivitamin supplementation containing folic acid is not associated with an increased likelihood of male births in a Chinese population. However, these results may have been affected by induced abortion or selective termination of pregnancy, and the findings must therefore be cautiously interpreted.

Interaction between the SLC19A1 gene and maternal first trimester fever on offspring neural tube defects.

BACKGROUND: Many studies have indicated that the reduced folate carrier gene (SLC19A1) is associated with an increased risk of neural tube defects (NTDs). However, the interaction between the SLC19A1 gene variant and maternal fever exposure and NTD risk remains unknown. The aim of this study was to investigate whether the risk for NTDs was influenced by the interactions between the SLC19A1 (rs1051266) variant and maternal first trimester fever. METHODS: We investigated the potential interaction between maternal first trimester fever and maternal or offspring SLC19A1 polymorphism through a population-based case-control study. One hundred and four nuclear families with NTDs and 100 control families with nonmal newborns were included in the study. SLC19A1 polymorphism was determined using polymerase chain reaction-restricted fragment length polymorphism. RESULTS: Mothers who had the GG/GA genotype and first trimester fever had an elevated risk of NTDs (adjusted odds ratio, 11.73; 95% confidence interval, 3.02-45.58) as compared to absence of maternal first trimester fever and AA genotype after adjusting for maternal education, paternal education, and age, and had a significant interactive coefficient (γ = 3.17) between maternal GG/GA genotype and first trimester fever. However, there was no interaction between offspring's GG/GA genotype and maternal first trimester fever (the interactive coefficient γ = 0.97) after adjusting for confounding factors. CONCLUSION: Our findings suggested that the risk of NTDs was potentially influenced by a gene-environment interaction between maternal SLC19A1 rs1051266 GG/GA genotype and first trimester fever. Maternal GG/GA genotype may strengthen the effect of maternal fever exposure on NTD risk in this Chinese population.

[Study on the related factors of prenatal health care among floating women in five cities of China].

OBJECTIVE: To understand the current status of prenatal health care (PHC) and its related factors for floating women of childbearing age, and to provide evidence for improving the quality of PHC at childbearing age. METHODS: With data from the reproductive health survey on floating population in five cities, Beijing, Nanjing, Xiamen, Shenzhen and Chongqing, in 2005, the distributions of PHC among floating women were described. Multivariate logistic regression was performed to investigate the factors related to the utilization of PHC. RESULTS: In 5 399 cases of valid questionnaires, 4 037 floating women who had the history of pregnant, cases who had or did not have PHC services would account for 75.3% (3 041/4 037) and 24.7% (996/4 037), respectively. The initial time of using the PHC service was significantly associated with the level of their education (P < 0.05) received. Data from the multivariate logistic regression analysis in PHC showed that there were differences between regions (P < 0.05). Proportions of women receiving PHC among those under 30 years and 30-39 were 4.09-folds (95% CI:3.11-5.39) and 1.98-folds (95% CI:1.61-2.43), respectively, when compared with that of women over 40-year-old. The proportion of women having received PHC with education levels of senior high school and above or junior high school, were 5.47-folds (95%CI:3.85-7.77) and 2.86-folds (95%CI:2.42-3.39) respectively, compared to that of women with education level of primary school or below. The proportion of married women having PHC was 2.36-folds (95%CI:1.07-5.22) of those unmarried women. The proportions of having PHC of women with one parity and two parities or with family planning certificate were 3.36-fold (95%CI: 2.33-4.84) and 1.61-fold (95% CI:1.12-2.30), 1.44-folds (95% CI:1.21-1.71) respectively, when compared with those women with three parities or without the certificate. CONCLUSION: Factors as having received higher education, being married, with less parities or having family planning certificate etc. showed protective effects on PHC for floating women of childbearing age. Based on PHC, education should be promoted among the floating women of childbearing age, which would contribute to the prevention and reduction of adverse outcomes related to reproductive health.

Association between risk of birth defects occurring level and arsenic concentrations in soils of Lvliang, Shanxi province of China.

The risk of birth defects is generally accredited with genetic factors, environmental causes, but the contribution of environmental factors to birth defects is still inconclusive. With the hypothesis of associations of geochemical features distribution and birth defects risk, we collected birth records and measured the chemical components in soil samples from a high prevalence area of birth defects in Shanxi province, China. The relative risk levels among villages were estimated with conditional spatial autoregressive model and the relationships between the risk levels of the villages and the 15 types of chemical elements concentration in the cropland and woodland soils were explored. The results revealed that the arsenic levels in cropland soil showed a significant association with birth defects occurring risk in this area, which is consistent with existing evidences of arsenic as a teratogen and warrants further investigation on arsenic exposure routine to birth defect occurring risk.

Arsenic levels in the soil and risk of birth defects: a population-based case-control study using GIS technology.

Arsenic is a highly dangerous metal that has been linked to a number of adverse health effects in both adults and children, including birth defects. Yet few epidemiologic studies have examined the relationship between arsenic levels in the soil and the risk of birth defects. The purpose of the authors' study was to examine this association among people exposed to environmental pollution in a developed area of China. The authors used global positioning system to locate the coordinates of 80 villages in 40 towns for soil sampling. Soil samples were analyzed for arsenic content. Logistic regression was used to investigate the relationship between exposure to arsenic and birth defects, controlling for potentially confounding factors. The authors found that exposure to arsenic in any amount increased the risk of birth defects. The positive association found between arsenic exposure and birth defects warrants further study, and future large-scale population-based studies are needed with an emphasis on individual-level exposure and confounding variables.

Twenty-year trends in the prevalence of disability in China.

OBJECTIVE: To evaluate changes in the age-adjusted prevalence of disability in transitional China from 1987 to 2006. METHODS: Data from nationally representative surveys conducted in 1987 and 2006 were used to calculate age-adjusted disability prevalence rates by applying appropriate sample weights and directly adjusting to the age distribution of the 1990 Chinese population. Trends were assessed in terms of average annual percentage change. FINDINGS: The estimated number of disabled people in China in 1987 and 2006 was 52.7 and 84.6 million, respectively, corresponding to a weighted prevalence of 4.9% and 6.5%. The age-adjusted prevalence of disability decreased by an average of 0.5% per year (average annual percentage change, AAPC: -0.5%; 95% confidence interval, CI: -0.7 to -0.4) during 1987-2006. However, it increased by an average of 0.3% (AAPC: 0.3%; 95% CI: 0.1 to 0.5) per year in males and by an average of 1.0% (AAPC: 1.0%; 95% CI: 0.8 to 1.2) per year among rural residents, whereas among females it showed an average annual decrease of 1.5% (AAPC: -1.5%; 95% CI: -1.7 to -1.3) and among urban residents, an average annual decrease of 3.9% (AAPC: -3.9%; 95% CI: -4.3 to -3.5). Despite significant declining trends for hearing and speech, intellectual and visual disabilities, the annual age-adjusted prevalence of physical and mental disabilities increased by an average of 11.2% (AAPC: 11.2%; 95% CI: 10.5 to 11.9) and 13.3% (AAPC: 13.3%; 95% CI: 10.7 to 16.2), respectively. CONCLUSION: In China, the age-adjusted prevalence of disability has declined since 1987, with inconsistencies dependent on the type of disability. These findings call for continuing and specific efforts to prevent disabilities in China.