Objective To construct profiles of health status based upon physical,mental and social support items in adult twins of Qingdao.Methods Grade of Membership(GoM) model was applied to a set of 31 indicators to construct ideal profiles.Results Four health profiles were identified: pure type Ⅰ(healthy),pure type Ⅱ(personality disorders),pure type Ⅲ(psychological symptoms) and pure type Ⅳ(physiological symptoms).The most frequently occurring combination in this population was profile Ⅰ,Ⅱ,Ⅳ(14.74%),followed by profile Ⅰ,Ⅱ,Ⅲ,Ⅳ(13.44%),and then type Ⅰ(11.08%).Only 13.56% of subjects fell completely into one single pure type.Conclusions One healthy type and three non-healthy types are determined.Most individuals exhibit some of the characteristics of two or more types,holding partial membership in multiple categories.

Objective To investigate the varying variances of the genetic components in birth cohorts.Methods Twin samples used in the current study were collected from the Chinese National Twin Registry and a two-wave study was conducted,in Qingdao and Lishui regions.Samples were broken down by birth cohort to create four subgroups:-1958,1959-1961,1962-1970 and 1970-.Structural equation models were fitted in each subgroup to estimate the genetic and environmental variances.Results From each birth cohort,weight and body mass index in 2012 appeared higher than those in 2001.Twins of 1971-cohort subgroup showed lower weight than in the other cohort subgroups.Except for the 1959-1961 cohort subgroup,the later birth cohorts were inversely related to the body mass indexes.Genetic factors might explain 54％-76％ of the total variations on the body mass index.Heritability of body mass index of twins born during 1959-1961 was increasing along with age.Conclusion Genetic factors might explain the main portion which related to the phenotypic variance of body mass index.Effects of genetic factors on body mass index of twins born during 1959-1961 might have increased along with age.

Objective: To explore the association between DNA methylation and body mass index (BMI) using Mendelian randomization analysis. Methods: A total of 469 participants were selected from the Chinese National Twin Registry in 2013, who were living in Shandong, Jiangsu, Zhejiang, and Sichuan provinces, and at least 18 years of age. A questionnaire survey and physical examination were conducted to collect demographic, clinical, and behavioral information. Peripheral blood cells were collected to detect genotype and methylation status. Association analyses between DNA methylation and BMI and between CpGs and cis-SNP were conducted. With rs748212 as the instrumental variable, the association between cg15053022 and BMI was explored using the Mendelian randomization method. Results: A total of 469 participants were selected. The mean age of participants was (44.8±13.2) years and the BMI was (25.0±3.8) kg/m². Nine BMI-related DNA methylation sites were found and DNA methylation site cg15053022 in the ATP4A gene was negatively associated with cis-SNP rs748212 (β=-0.020); the mean methylation level of AA, AC, and CC were 0.212±0.025, 0.242±0.024, and 0.264±0.028, respectively. rs748212 was associated with BMI (β=0.04, P=0.007) and closely related to cg15053022 (F=237.66, P=0.143). Mendelian randomization analysis showed lower methylation levels at cg15053022 were associated with higher BMI (β=-1.97, P<0.001). Conclusion This study supported the impact of cg15053022 methylation in the ATP4A gene on BMI using Mendelian randomization analysis and provided the basis for using Mendelian randomization analysis in methylation studies.

BACKGROUND/OBJECTIVES: This study examined the relationship between famine exposure in early life and the risk of type 2 diabetes in adulthood during the 1959–1961 Chinese Famine. SUBJECTS/METHODS: A total of 3,418 individuals aged 35–74 years free of diabetes from two studies in 2006 and 2009 were followed up prospectively in 2009 and 2012, respectively. Famine exposure was classified as unexposed (individuals born in 1962–1978), fetal exposed (individuals born in 1959–1961), child exposed (individuals born in 1949–1958), and adolescent/adult exposed (born in 1931–1948). A logistic regression model was used to assess the relationship between famine exposure and diabetes after adjustment for potential covariates. RESULTS: During a three-year follow-up, the age-adjusted incidence rates of type 2 diabetes were 5.7%, 14.5%, 12.7%, and 17.8% in unexposed, fetal-exposed, child-exposed, and adolescent/adult-exposed groups, respectively (P < 0.01). Relative to the unexposed group, the relative risks (95% confidence interval) for diabetes were 2.15 (1.29–3.60), 1.53 (0.93– 2.51), and 1.65 (0.75–3.63) in the fetal-exposed, child-exposed, and adolescent/adult-exposed groups, after controlling for potential covariates. The interactions between famine exposure and obesity, education level, and family history of diabetes were not observed, except for the urbanization type. Individuals living in rural areas with fetal and childhood famine exposure were at a higher risk of type 2 diabetes, with relative risks of 8.79 (1.82–42.54) and 2.33 (1.17–4.65), respectively. CONCLUSIONS These findings indicate that famine exposure in early life is an independent predictor of type 2 diabetes, particularly in women. Early identification and intervention may help prevent diabetes in later life.

Objective To investigate both genetic and environmental influences on the exercise participation and sedentary behavior in Qingdao,Shandong province and 326 in Lishui, Zhejiang province. Methods 568 twin pairs,including 242 in Qingdao and 326 in Lishui,were studied. Exercise participation was measured by two questions on the frequency and intensity and then divided into two groups. Sedentary behavior was measured by one question as‘how long do you spend on sitting every day’. Variance component models based on twins was used to estimate the genetic and environmental factors on these traits. Results The average age in monozygotic twins was(41.14 ± 10.11)while in dizygotic twins it was(41.23 ± 9.89). Genetic factors accounted 78%(35%-96%)and 59%(0-94%)for exercise participation variance in Qingdao and Lishui in people aged between 20 and 40. However,there were no heritability noticed on physical activity in people older than 40 years of age. Rates of heritability on sedentary behavior in Qingdao and Lishui were 68%(59%-75%)and 32%(7%-62%),respectively. Conclusion Results from the study suggested that sedentary behavior in Chinese people was influenced by genetic factors,which could also explain much of the exercise participation variance in people aged between 20 and 40.

OBJECTIVESince the incidence rates and risk factor for type 2 diabetes in Chinese populations had not been well known, the aim of this study was to evaluate the impact of weight change and other risk factors on incident type 2 diabetes in Qingdao, China.

METHODSA prospective population-based cohort study was carried out, based on subjects aged 35-74 years who participated in the 'Qingdao Diabetes Survey' in 2006. Subjects were free of diabetes at baseline. A total of 1 294 subjects attended the follow up survey between 2009 and 2011. The diagnostic criteria for Diabetes was classified according to both the World Health Organization and the International Diabetes Federation 2006. A logistic regression was built using the backward stepwise selection to assess the effects of risk factors on the incident type 2 diabetes.

RESULTSDuring a 4-year follow up period, 120 cases with incident type 2 diabetes were identified, with cumulative incidence of diabetes as 11.8% . Participants who developed type 2 diabetes were significantly older, having significantly higher age-adjusted BMI/waist circumference/systolic blood pressure and total cholesterol, than those subjects who remained non-diabetic both in urban and rural areas. Among individuals with no diabetes at the baseline, factors as age, living in the rural areas, baseline BMI and weight change had all independently contributed to the development of diabetes. The multivariate adjusted relative risks (95%CIs) related to the incidence of diabetes were 1.45 (1.13-1.87), 1.93 (1.12-3.34), 1.46 (1.05-2.03) and 1.49 (1.18-1.88), respectively, for a one standard deviation increase in continuous variables. Compared with the reference group of non-obese and with stable weight, factor as weight loss >5% and BMI <28 kg/m² were independently associated with a 67% (RR = 0.33, 95% CI: 0.11-0.97)reduction in the risk of type 2 diabetes, while BMI >28 kg/m² could increase the risk across the levels of weight change. Similar trends were observed in higher waist and weight gain at baseline.

CONCLUSIONThis study confirmed the critical importance of obesity in the development of type 2 diabetes. Baseline BMI and weight gain appeared independent predictors on type 2 diabetes.

Adult ; Aged ; Body Mass Index ; Body Weight ; China ; epidemiology ; Diabetes Mellitus, Type 2 ; epidemiology ; Female ; Follow-Up Studies ; Humans ; Incidence ; Logistic Models ; Male ; Middle Aged ; Prospective Studies ; Risk Factors ; Weight Gain

OBJECTIVETo explore the heritability of body mass index (BMI) in twins across different regions and genders in China.

METHODSA total of 11 122 adult twin pairs from the Chinese National Twin Registry were interviewed. A structural equation model was used to estimate the heritability of BMI.

RESULTSThis study included 6 226 monozygotic twin pairs and 4 896 dizygotic twin pairs, with the age range as 25-85 (39.0 ± 10.8) years. Under stratified analysis by region, results showed that the highest and lowest rates on heritability of BMI in men were seen in Tianjin and Zhejiang, as 67.8% (95% CI: 50.1%-85.8%) and 42.1% (95% CI: 27.2%-60.9%), while in women were seen in Sichuan and Heilongjiang as 56.2% (95% CI: 47.5%-70.0%) and 11.2% (95% CI: 0.0%-31.7%), respectively. Results from the stratified analysis showed that, by gender, the heritability of BMI in men was higher than that in women from the same region. The biggest differences of heritability of BMI between men and women were seen in Heilongjiang as 55.3% (95% CI: 35.5%-80.0%) and 11.2% (95% CI: 0-31.7%), while the smallest differences were seen in Sichuan as 61.5% (95% CI: 40.7%-86.4%) and 56.2% (95% CI: 47.5%-70.0%), respectively.

CONCLUSIONThe heritability of BMI across different regions and genders showed certain differences in the Chinese twins.

Adult ; Aged ; Aged, 80 and over ; Asian Continental Ancestry Group ; genetics ; Body Mass Index ; China ; Cities ; Female ; Humans ; Male ; Middle Aged ; Registries ; Twins, Dizygotic ; genetics ; statistics & numerical data ; Twins, Monozygotic ; genetics ; statistics & numerical data

OBJECTIVETo understand the change trend of birth weight of twins in China from 1995 to 2012.

METHODSA total of 10 827 twins born between 1995 and 2012 registered in national twin registry system in 8 provinces in China were included in this study. A retrospective study was conducted to analyze the change trend of twin's birth weight.

RESULTSMean birth weight of twins decreased by 0.01 kg every five years after adjusting sex, ovum type and place of birth (P = 0.041). The birth weight decreased both in superior twin and in inferior twin over time. After 2007, the birth weight of superior twin decreased by 0.008 kg each year, while the birth weight of inferior twin decreased by 0.014 kg each year. Mean relative difference in birth weight and birth weight discordant rate decreased before 2002, then increased from the lowest point 8.16% and 16.20% to highest point 9.99% and 22.40% respectively.

CONCLUSIONThe birth weight of twins in China decreased between 1995 and 2012, while the birth weight discordant rate increased, suggesting that close attention should be paid to the discordance of twin body weight to reduce the risk of adverse health outcome.

Birth Rate ; Birth Weight ; China ; epidemiology ; Humans ; Infant, Newborn ; Registries ; Retrospective Studies ; Twins

OBJECTIVETo study the correlation between fingerprints and body size indicators in adulthood.

METHODSSamples were composed of twins from two sub-registries of Chinese National Twin Registry (CNTR), including 405 twin pairs in Lishui and 427 twin pairs in Qingdao. All participants were asked to complete the field survey, consisting of questionnaire, physical examination and blood collection. From the 832 twin pairs, those with complete and clear demographic prints were selected as the target population. Information of Fingerprints pixel on the demographic characteristics of these 100 twin pairs and their related adulthood body type indicators were finally chosen to form this research. Descriptive statistics and mixed linear model were used for data analyses.

RESULTSIn the mixed linear models adjusted for age and sex, data showed that the body fat percentage of those who had arches was higher than those who did not have the arches (P = 0.002), and those who had radial loops would have higher body fat percentage when compared with ones who did not (P = 0.041). After adjusted for age, there appeared no statistically significant correlation between radial loops and systolic pressure, but the correlations of arches (P = 0.031)and radial loops (P = 0.022) to diastolic pressure still remained statistically significant.

CONCLUSIONStatistically significant correlations were found between fingerprint types and body size indicators, and the fingerprint types showed a useful tool to explore the effects of uterine environment on health status in one's adulthood.

Adult ; Body Size ; Dermatoglyphics ; Diseases in Twins ; epidemiology ; Female ; Health Status ; Humans ; Male ; Surveys and Questionnaires ; Twins

Objective: To analyze the heritability of diabetes among the Chinese twin adults. Methods: A total of 10 253 same-sex twin pairs aged 25 years and older, were selected from the Chinese National Twin Registry (CNTR) program. Heritability of diabetes was calculated by using the structural equation model. Results: After adjusted for age and gender, the overall heritability rates of diabetes were 0.41 (0.15-0.75), 0.83 (0.72-0.91) and 0.34 (0.04-0.73) in the <45 and ≥45 years twin pairs, respectively. After adjusted for age, rates of heritability appeared as 0.37 (0.05-0.78) and 0.88 (0.79-0.94) in men and women, respectively. Conclusions Diabetes is affected by both genetic and environmental factors. The genetic effect of diabetes seemed stronger on female than that on male twins but was dying down along with ageing.