1.Nutrition status of children under 5 years old and some influence factors in Kontum province, 2001
Journal of Preventive Medicine 2004;14(1):71-76
A cross-sectional study was carried out on 1,500 subjects at 30 communes collected randomly (investigated 50 children and 50 mothers per commune) about nutrition status of children under 5 years old and some influenced factors in Kontum province, in 2001. The results: the percentage of malnutrition was high level according to WHO criteria, underweight was 36.9%, stunting was 46.3%, and wasting was 8.3%. The malnutrition rates of boys and girls were significant difference (P>0.05). The children of ethnic minorities were higher about the malnutrition rates than children of Kinh people. The malnutrition rates in the child of illiterate mothers was the highest
Nutritional Status
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child
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Malnutrition
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standards
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Thinness
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epidemiology
2.Association of lead exposure with stunting and underweight among children aged 3-5 years in China.
Zheng LI ; Yao Bin LYU ; Feng ZHAO ; Qi SUN ; Ying Li QU ; Sai Sai JI ; Tian QIU ; Ya Wei LI ; Shi Xun SONG ; Miao ZHANG ; Ying Chun LIU ; Jia Yi CAI ; Hao Can SONG ; Xu Lin ZHENG ; Bing WU ; Dan Dan LI ; Ying LIU ; Ying ZHU ; Zhao Jin CAO ; Xiao Ming SHI
Chinese Journal of Preventive Medicine 2022;56(11):1597-1603
Objective: To evaluate the association of lead exposure with stunting and underweight among children aged 3-5 years in China. Methods: Data was collected from China National Human Biomonitoring (CNHBM) between January 2017 and December 2018. A total of 3 554 children aged 3-5 years were included. Demographic characteristic, lifestyle and nutritional status were collected through questionnaires. Height and weight were measured by standardized method. Stunting and underweight status were determined by calculating height for age Z-score and weight for age Z-score. Blood and urine samples were collected to detect the concentrations of blood lead, urinary lead and urinary creatinine. Children were stratified into 4 groups (Q1 to Q4) by quartiles of blood lead level and corrected urinary lead level, respectively. Complex sampling logistic regression models were applied to evaluate the association of the blood lead level, urinary lead level with stunting and underweight. Results: Among 3 554 children, the age was (4.09±1.06) years, of which 1 779 (80.64%) were female and 1 948 (55.84%) were urban residents. The prevalence of stunting and wasting was 7.34% and 2.96%, respectively. The M (Q1, Q3) for blood lead levels and urinary lead levels in children was 17.49 (12.80, 24.71) μg/L, 1.20 (0.61, 2.14) μg/g Cr, respectively. After adjusting for confounding factors, compared with the lowest blood lead concentration group Q1, the risk of stunting gradually increased in the Q3 and Q4 group (Ptrend=0.010), with OR (95%CI) values of 1.40 (0.80-2.46) and 1.80 (1.07-3.04), respectively. Compared with the lowest urinary lead concentration group Q1, the risk of stunting still increased in the Q3 and Q4 group (Ptrend=0.012), with OR (95%CI) values of 1.69 (1.01-2.84) and 1.79 (1.05-3.06), respectively. The correlation between the lead exposure and underweight was not statistically significant (P>0.05). Conclusion: Lead exposure is positively associated with the risk of stunting among children aged 3-5 years in China.
Child
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Female
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Humans
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Infant
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Male
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Lead
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Thinness/epidemiology*
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Growth Disorders/epidemiology*
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Body Height
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Nutritional Status
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Prevalence
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China/epidemiology*
3.Comparison of two child growth standards in assessing the nutritional status of children under 6 years of age.
Shuo WANG ; Yue MEI ; Zhen Yu YANG ; Qian ZHANG ; Rui Li LI ; Yu Ying WANG ; Wen Hua ZHAO ; Tao XU
Chinese Journal of Pediatrics 2023;61(8):700-707
Objective: To compare the application of China growth standard for children under 7 years of age (China standards) and World Health Organization child growth standards (WHO standards) in evaluating the prevalence of malnutrition in children aged 0-<6 years in China. Methods: The research data came from the national special program for science & technology basic resources investigation of China, named "2019-2021 survey and application of China's nutrition and health system for children aged 0-18 years". Multi-stage stratified random sampling was used to recruit 28 districts (regions) in 14 provinces, autonomous regions or municipalities across the country. Children (n=38 848) were physically measured and questionnaires were conducted in the guardians of the children. The indicators of stunting, underweight, wasting, overweight and obesity were evaluated by China standards and WHO standards respectively. Chi-square test was used to comparing the prevalence of each nutritional status between the two standards, as well as the comparison between the two standards by gender and age. Results: Among the 38 848 children, 19 650 were boys (50.6%) and 19 198 were girls (49.4%), 19 480 urban children (50.1%) and 19 368 rural children (49.9%). The stunting, underweight and wasting cases in the study population were 2 090 children (5.4%), 1 354 children (3.5%) and 1 276 children (3.3%) according to the China standards, and 1 474 children (3.8%), 701 children (1.8%) and 824 children (2.1%) according to the WHO standards, respectively; the above rates according to the China standards were slightly higher than those to the WHO standards (χ2=111.59, 213.14, and 99.99, all P<0.001). The overweight and obesity cases in the study population were 2 186 children (5.6%) and 1 153 children (3.0%) according to the China standards, and 2 210 children (5.7%) and 1 186 children (3.1%) according to the WHO standards, with no statistically significant differences (χ2=0.14 and 0.48, P=0.709 and 0.488, respectively). Compared to the results based on WHO standards, the China standards showed a lower prevalence of overweight and obesity in boys (χ2=14.95 and 5.85, P<0.001 and =0.016, respectively), and higher prevalence of overweight in girls (χ2=12.60, P<0.001); but there was no statistically significant differences in girls' obesity prevalence between the two standards (χ2=2.62, P=0.106). Conclusions: In general, the prevalence of malnutrition among children aged 0-<6 years based on China standards is slightly higher than that on WHO standards. To evaluate the nutritional status of children, it is advisable to select appropriate child growth standards based on work requirements, norms or research objectives.
Male
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Female
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Child
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Humans
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Child, Preschool
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Nutritional Status
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Overweight/epidemiology*
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Thinness/epidemiology*
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Obesity/epidemiology*
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Malnutrition/epidemiology*
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Growth Disorders/epidemiology*
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China/epidemiology*
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Prevalence
4.Trend of Obesity in School Age Children in Seoul Over the Past 23 Years.
Young Shin PARK ; Dong Hwan LEE ; Joong Myung CHOI ; Yun Ju KANG ; Chong Hee KIM
Korean Journal of Pediatrics 2004;47(3):247-257
PURPOSE: The aim of this study was to evaluate the change in prevalence and the epidemiology of obesity in school age children of Seoul, Korea during the last 23 years with coherency and under the same standards. METHODS: We used the new 1998 standard weight for height to calculate obesity on the personal data from five years and produced a coefficient of correlation that could be applied to previous obesity prevalence results. RESULTS: From age six to 17, the average body mass index increased 5.7 in boys and 6.2 in girls. The prevalence of obesity according to age peaked around age 11 and age 13-14, and increased again at 16-17 in boys. In girls, there was a peak at the age of 10 and a second peak which was at age 16 in 1979, but the age of the second peak gradually came down to a younger age, to age 13, in 2002. Obesity in girls increased steadily after the second peak. In 1979 and 1981, there were many more underweight children than obese. In boys, obesity had risen to 11.0% by 1997 and rose abruptly to 17.9% by 2002 and in girls, to 9.0% by 1997 and 10.9% by 2002. Mild, moderate, and severe obesity also increased with the increase of obesity. CONCLUSION: As Korea became developed, obesity became more frequent than underweight. Obesity increased rapidly and the increase rate accelerated in boys, whereas though it increased, the increase rate slowly decreased in girls.
Body Mass Index
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Child*
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Epidemiology
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Female
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Humans
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Korea
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Obesity*
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Obesity, Morbid
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Prevalence
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Seoul*
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Thinness
5.Evaluation of risk factors associated with fragility fractures and recommendations to optimise bone health in children with long-term neurological condition.
Xue Yi Jessica LEOW ; Jonathan Tian Ci TAN ; Tong Hong YEO ; Kenneth Pak Leung WONG ; Arjandas MAHADEV ; Bixia ANG ; Rashida Farhad VASANWALA ; Zhi Min NG
Singapore medical journal 2023;64(9):550-556
INTRODUCTION:
The growing years are paramount for bone growth and mineral accrual. Children with long-term neurological condition (LTNC) have multiple risk factors for poor bone health and fragility fractures. In Singapore, this has not been studied systematically. Therefore, we aimed to evaluate the risk factors associated with fragility fractures in children with LTNC.
METHODS:
In this study, the search for fragility fractures was done by a retrospective review of patients with LTNC on follow-up in the paediatric neurology clinic and patients who presented with fracture to the paediatric orthopaedic clinic. Information on patients' demographics, medical history, intervention, biochemical bone markers and fracture history was collected.
RESULTS:
In a tertiary clinic population of 136 patients with LTNC, 65% were dependent on mobility (Gross Motor Function Classification System [GMFCS] V), 60% were underweight and 60% were fed via gastrostomy or nasogastric tube, or were on oral pureed diet. Furthermore, 60% were on anticonvulsants. The fracture rate was 3% in this population and was associated with low-impact activities such as transfer and dressing. Only 7.4% and 33% of the patients had undergone measurements of vitamin D and calcium levels, respectively.
CONCLUSION
The local prevalence of fragility fractures in children with LTNC on follow-up at the neurology clinic was found to be 3%. Risk factors identified were limited ambulation and compromised nutritional status associated with feeding difficulty. Recommendations to optimise bone health in children with LTNC were made. These include promoting weight-bearing activities, looking out for underweight children, avoiding vitamin D deficiency and ensuring adequate calcium intake.
Humans
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Child
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Bone Density
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Calcium
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Thinness/epidemiology*
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Fractures, Bone/etiology*
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Risk Factors
6.Independent and combined effects of pre-pregnancy BMI and gestational diabetes on early adiposity rebound timing in children.
Shi Qi FAN ; Shuang Qin YAN ; Bei Bei ZHU ; Xiao Zhen LI ; Juan TONG ; Chun Gang LI ; Hui CAO ; Xiao Yan WU ; Liang Liang XIE ; Zhao Lian WEI ; Fangbiao TAO
Chinese Journal of Epidemiology 2022;43(10):1626-1631
Objective: To examine the independent and combined effects of pre-pregnancy BMI and gestational diabetes (GDM) on early adiposity rebound (AR) timing in children. Methods: Based on the "Ma'anshan Birth Cohort Study", 2 896 eligible maternal and infant pairs were recruited. In the cohort, we collected pre-pregnancy height, weight, 24 to 28 weeks GDM diagnosis, follow-up at 42 days, three months, six months, nine months of age, and every six months after one year of age, and continuously followed up to 6 years old, and obtained the child's length/height, weight, and other data. The intensity of the association between pre-pregnancy BMI, GDM, and early AR timing was analyzed by the multivariate logistic regression model. Multiplication and additive models were used to analyze how pre-pregnancy BMI and GDM influenced early AR timing in children. Results: The prevalence of underweight, average weight, overweight, and obesity before pregnancy were 23.2% (672), 66.4% (1 923), 8.7% (251), and 1.7% (50). The prevalence of GDM was 12.4%. We found that 39.3% of children had AR, and the average age at AR was (4.38±1.08). The results of multifactorial logistic regression analysis showed that pre-pregnancy overweight (OR=1.67,95%CI:1.27-2.19), pre-pregnancy obesity (OR=3.05,95%CI:1.66-5.56), and maternal GDM (OR=1.40,95%CI:1.11-1.76) were risk factors for early AR timing in children. In contrast, pre-pregnancy underweight (OR=0.60,95%CI:0.49-0.73) was a protective factor for early AR timing in children. Compared with the different effects of pre-pregnancy overweight/obesity and maternal GDM alone, the combined effect caused a higher risk of early AR timing in children, with OR values (95%CI) were 2.03 (1.20-3.44), 3.43 (1.06-11.12), respectively. The multiplication and additive models showed no interaction between pre-pregnancy BMI and GDM-influenced early AR timing in children. Conclusion: Higher pre-pregnancy BMI and maternal GDM are the independent risk factors for the early AR timing in children, and the co-occurrence of the two is higher risks, but there was no statistical interaction.
Child
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Infant
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Female
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Pregnancy
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Humans
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Adiposity
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Diabetes, Gestational/epidemiology*
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Overweight/epidemiology*
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Thinness
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Cohort Studies
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Body Mass Index
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Obesity
7.Malnutrition prevalence in lasa xizang children and adolescents.
Biomedical and Environmental Sciences 2014;27(8):614-626
OBJECTIVETo assess the prevalence of malnutrition among children and adolescents in Xizang (Tibet).
METHODSWe analyzed data from the Chinese National Survey on Students' Constitution and Health for the years 1995, 2000, 2005, and 2010 pertaining to Tibetan children and adolescents in lase (Lhasa), aged 7-18 years old. Numbers of survey subjects for these years were: 2393, 2754, 2397, and 2643, respectively.
RESULTSOur results indicated that the rate of occurrence of stunting in Tibet has evidenced a gradual decline: for boys, from 26.8% in 2000 to 9.3% in 2010; and for girls, from 25.8% in 2000 to 10.8% in 2010. In general, the wasting rate for both boys and girls in Tibet has gradually decreased over time: for boys, from 17.7% in 1995 to 4.6% in 2005; and for girls from 12.5% in 1995 to 2.3% in 2005. The stunting rates of boys aged 7-13 years old and of girls aged 7-11 years old were 67.5% and 53.1%, respectively, while these rates for boys aged 14-18 years old and girls aged 12-18 years old were 32.5% and 46.9%, respectively.
CONCLUSIONStunting and wasting rates of Tibetan children and adolescents indicate a gradual declining trend over time. The stunting rates of both boys and girls during early puberty were significantly higher than those during late puberty.
Adolescent ; Child ; Cross-Sectional Studies ; Female ; Growth Disorders ; epidemiology ; Humans ; Male ; Malnutrition ; epidemiology ; Nutritional Status ; physiology ; Prevalence ; Thinness ; epidemiology ; Tibet ; epidemiology
8.Relationship between pre-pregnant body mass index, maternal weight gain and small for gestational age.
Tingting PENG ; Fujuan YUE ; Fang WANG ; Yongliang FENG ; Weiwei WU ; Suping WANG ; Email: SPWANG88@163.COM. ; Yawei ZHANG ; Hailan YANG
Chinese Journal of Epidemiology 2015;36(6):644-648
OBJECTIVETo investigate the relationship between maternal pre-pregnancy body mass index, weight gain during pregnancy and small for gestational age (SGA) birth so as to provide evidence for the development of comprehensive prevention programs on SGA birth.
METHODSBetween March, 2012 and July, 2014, 4 754 pregnant women were asked to fill in the questionnaires which were collected from the First Affiliated Hospital of Shanxi Medical University. Data related to general demographic characteristics, pregnancy and health status of those pregnant women was collected and maternal pre-pregnancy body mass index and maternal weight gain were calculated. Subjects were divided into different groups before the effect of maternal pre-pregnancy body mass index and weight gain during pregnancy on SGA birth were estimated.
RESULTSThe overall incidence of SGA birth was 9.26% (440/4 754). Proportions of SGA birth from pre-pregnant, underweight group, normal weight group, overweight and obese groups were 9.85%, 8.54% and 9.45%, respectively. Results from multi-factor logistic regression analyses showed that after adjusting the confounding factors as age, history on pregnancies etc., women with high pre-pregnancy BMI showed a lower incidence of SGA than those under normal pre-pregnancy BMI (OR = 0.714, 95% CI: 0.535-0.953). Different weight gains during pregnancy were statistically significant (χ(2) = 8.811, P = 0.012). Incidence of SGA birth that was below the recommended range in the 2009 Institute of Medicine Guidelines (12.20%) was higher than those within (9.23%) or beyond (8.45%) the recommended range. Results from the multi-factor logistic regression analyses showed that, after adjusting the confounding factors as age, pregnancy history etc., factor as weight gain below the recommended level could increase the risk of SGA (OR = 1.999, 95% CI: 1.487-2.685). In the underweight, normal weight, overweight or obese groups, with weight gain during pregnancy below the range, the incidence of SGA showed an increase (OR = 2.558, 95% CI: 1.313-4.981, OR = 1.804, 95% CI: 1.258-2.587, OR = 3.108, 95% CI: 1.237-7.811). There was no interaction of addictive or multiplicative models between these two factors under 'interaction analysis'.
CONCLUSIONWomen with high pre-pregnancy BMI presented a lower incidence of SGA than those within the normal range. Insufficient weight gain during pregnancy could increase the risk of SGA delivery. These findings called for attention to be paid to the gestational weight gain, in order to decrease the risk of SGA.
Body Mass Index ; China ; epidemiology ; Female ; Humans ; Incidence ; Infant, Newborn ; Infant, Small for Gestational Age ; Obesity ; epidemiology ; Overweight ; epidemiology ; Pregnancy ; Risk Factors ; Thinness ; epidemiology ; Weight Gain
9.Analysis of incidence and associated factors of preterm birth based on pre-pregnancy body mass index stratification.
Shao Fei SU ; Shen GAO ; En Jie ZHANG ; Rui Xia LIU ; Wen Tao YUE ; Jian Hui LIU ; Shuang Hua XIE ; Yue ZHANG ; Cheng Hong YIN
Chinese Journal of Preventive Medicine 2023;57(6):899-904
Objective: To analyze the incidence of preterm birth based on pre-pregnancy body mass index (BMI) stratification and explore the associated factors of preterm birth among pregnant women at different BMI stratifications. Methods: From February 2018 to December 2020, pregnant women who participated in China Birth Cohort Study (CBCS) and gave birth at Beijing Obstetrics and Gynecology Hospital were enrolled as the study subjects. Electronic Data Capture System and standard structured questionnaires were used to collect data related to pre-pregnancy, pregnancy, and delivery for pregnant women. Pregnant women were divided into the low-weight group, normal-weight group and overweight group based on their pre-pregnancy BMI. A Cox proportional hazards model was used to analyze the associated factors of preterm birth among pregnant women with different BMI before pregnancy. Results: A total of 27 195 singleton pregnant women were included, with a preterm birth rate of 5.08% (1 381/27 195). The preterm birth rates in the low-weight group, normal-weight group and overweight group were 4.29% (138/3 219), 4.63% (852/18 390) and 7.00% (391/5 586) respectively (P<0.001). After adjusting for relevant factors, the Cox proportional hazards model showed that the risk of preterm birth in the overweight group was 1.457 times higher than that in the normal-weight group (95%CI: 1.292-1.643). Preeclampsia-eclampsia (HR=2.701, 95%CI: 1.318-5.537) was the associated factor for preterm birth in the low-weight group. Advanced maternal age (HR=1.232, 95%CI: 1.054-1.441), history of preterm birth (HR=4.647, 95%CI: 3.314-6.515), vaginal bleeding in early pregnancy (HR=1.613, 95%CI: 1.380-1.884), and preeclampsia-eclampsia (HR=3.553, 95%CI: 2.866-4.404) were associated factors for preterm birth in the normal-weight group. Advanced maternal age (HR=1.473, 95%CI: 1.193-1.818), history of preterm birth (HR=3.209, 95%CI: 1.960-5.253), vaginal bleeding in early pregnancy (HR=1.636, 95%CI: 1.301-2.058), preeclampsia-eclampsia (HR=2.873, 95%CI:2.265-3.643), and pre-gestational diabetes mellitus (HR=1.867, 95%CI: 1.283-2.717) were associated factors for preterm birth in the overweight group. Conclusion: Pre-pregnancy overweight is an associated factor for preterm birth, and there are significant differences in the associated factors of preterm birth among pregnant women with different BMI before pregnancy.
Pregnancy
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Infant, Newborn
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Female
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Humans
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Body Mass Index
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Overweight/epidemiology*
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Premature Birth/epidemiology*
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Pre-Eclampsia/epidemiology*
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Cohort Studies
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Eclampsia
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Incidence
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Risk Factors
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Thinness/epidemiology*
10.Body mass index and cancer incidence:a prospective cohort study in northern China.
Lanwei GUO ; Ni LI ; Gang WANG ; Kai SU ; Fang LI ; Lin YANG ; Jiansong REN ; Sheng CHANG ; Shuohua CHEN ; Shouling WU ; Jie HE ; Min DAI
Chinese Journal of Epidemiology 2014;35(3):231-236
OBJECTIVETo evaluate the association and its strength between body mass index (BMI, kg/m(2)) and cancer incidence in a large-scale population-based cohort study.
METHODSA dynamic cohort was established on May 1, 2006. Baseline information on demography, lifestyle, anthropometry such as body height and weight, were collected during the first interview, and cancer incidence, mortality and other related outcome information were obtained through active follow-up every two years and passive follow-up every year. Cancer cases diagnosed within 1 year follow-up period were excluded. Multivariable Cox proportional-hazards regression model was used to calculate the hazard ratios (HRs)and 95% confidence interval (CI) between BMI and cancer incidence after adjusted for age group, education level, tobacco smoking (smokers and non-smokers), alcohol consumption (drinkers or non-drinkers) and HBsAg status (positive or negative, for liver cancer only) when appropriate. Repeated analysis was carried out on male lung cancer, male liver cancer and female breast cancer, stratified by tobacco smoking, HBsAg status and menopausal status respectively.
RESULTSBy December 31, 2011, a total of 133 273 subjects, including 106 630 (80.01%)males and 26 643(19.99%)females were enrolled in the cohort. There were 570 531.02 person-years of follow-up and 4.28-year of average follow-up period. According to the Guidelines for Prevention and Control of Overweight and Obesity in Chinese Adults, study subjects were divided into groups as: underweight (BMI<18.5 kg/m(2)), normal weight (BMI 18.5 kg/m(2)-23.9 kg/m(2)), overweight (BMI 24.0 kg/m(2)-27.9 kg/m(2)) and obese(BMI≥28.0 kg/m(2)). In males, 2 387 (2.24%) were underweight, 45 090(42.29%)were normal weight, 43 774 (41.05%) were overweight and 15 379 (14.42%) were obese. Meanwhile, in females, 858 (3.22%)were underweight, 14 037 (52.69%) were normal weight, 8 507 (31.93%) were overweight and 3 241 (12.16%) were obese. A total of 1 647 incident cancer cases among different cancers were collected during the follow-up, including 1 348 in men and 299 in women. Results from Multivariate Cox proportional-hazards regression model showed that 'underweight' increased the risk on both gastric cancer incidence (adjusted HR = 3.82, 95% CI: 1.97-7.38) and liver cancer incidence (adjusted HR = 3.00, 95% CI:1.36-6.65) in males, while both 'overweight' (adjusted HR = 1.98, 95% CI:1.03-3.82) and 'obesity' (adjusted HR = 2.75, 95% CI: 1.25-6.06) increased the risk of colon cancer incidence in males. But for bladder cancer incidence in males, overweight seemed being protective (adjusted HR = 0.44, 95%CI:0.23-0.84). And for lung cancer incidence in males, both overweight and obesity were protective as well (adjusted overweight vs. normal weight, HR = 0.59, 95%CI: 0.46-0.76;adjusted obese vs. normal weight, HR = 0.64, 95%CI: 0.44-0.92). In females, obesity increased the risk of breast cancer incidence(adjusted HR = 1.86, 95%CI:1.05-3.31). Further analysis for lung cancer cases stratified by tobacco smoking, data showed that overweight decreased the risk of lung cancer in both male non-smokers (adjusted HR = 0.50, 95%CI:0.35-0.72) and male smokers (adjusted HR = 0.70, 95%CI:0.50-0.98) while obesity decreased the risk of lung cancer in male non-smokers(adjusted HR = 0.57, 95% CI:0.33-0.97), but not in smokers (adjusted HR = 0.72, 95%CI:0.43-1.21). Stratified analysis in females by menopausal status, data showed that obesity increased the incidence of breast cancer in postmenopausal subjects (adjusted HR = 1.97, 95% CI:1.01-3.82), but not in premenopausal subjects.
CONCLUSIONThe association between BMI and cancer incidence varied by cancer site. Underweight increased the risk of gastric cancer and liver cancer in males, and obesity increased the risk of colon cancer in males, breast cancer and ovarian cancer in females. However, overweight might played a protective role in lung cancer incidence and bladder cancer incidence in males and obesity might play a protective role in lung cancer incidence in male non-smokers.
Adult ; Body Mass Index ; Breast Neoplasms ; epidemiology ; China ; epidemiology ; Cohort Studies ; Colonic Neoplasms ; epidemiology ; Female ; Humans ; Incidence ; Lung Neoplasms ; epidemiology ; Male ; Middle Aged ; Obesity ; epidemiology ; Overweight ; epidemiology ; Risk Factors ; Stomach Neoplasms ; epidemiology ; Thinness ; epidemiology