中国3-44岁居民铁营养状况及其与肥胖状况的相关性研究

【作者】 杜文雯；

【导师】 张兵；

【作者基本信息】 中国疾病预防控制中心 ， 营养与食品卫生学， 2008， 硕士

【摘要】 研究背景:贫血与肥胖是影响我国居民健康的两个营养问题,而铁缺乏是我国居民贫血的主要原因。一直以来,研究者多认为铁缺乏主要是由营养不良引起的,婴幼儿、孕妇、乳母、青春期女性及老年人是贫血的高危人群,较少有文献关注超重、肥胖与铁缺乏的关系。国内外学者对肥胖与铁缺乏关系的研究结果存在着较大的争议,我国尚未见有普遍代表性的肥胖与铁营养状况的研究报道。研究目的:本研究旨在利用“2002年中国居民营养与健康状况调查”的数据,比较我国居民中超重、肥胖者与正常体重者的铁缺乏及贫血状况,分析超重、肥胖与铁缺乏及贫血的关系,探索我国超重、肥胖人群中铁营养状况的影响因素。研究方法:研究数据来源于2002年中国居民营养与健康状况调查(以下简称02年营养调查)。研究对象为3—44岁调查对象,排除没有血红蛋白检测数据者及孕妇、乳母,共计129,191例。按年龄将其分为3—5岁儿童、6—11岁儿童、12—17岁青少年、18—44岁成年人四组,各组人数分别为11945、30413、17784、69049例。主要包括的分析指标有人口统计学指标、体质状况指标、铁营养状况指标、膳食指标及体力活动指标五大类。应用方差分析、卡方检验、相关分析、多因素分析、因子分析等统计分析方法,分析不同体质状况人群铁营养状况的差异及变化规律,探讨超重、肥胖与铁缺乏的关系,以及超重、肥胖人群中影响铁营养状况的危险因素。研究结果:1.超重、肥胖状况:超重、肥胖率在18—44岁成年人中最高,分别为22.86%和6.57%;其次是3—5岁儿童,分别为8.88%和6.80%;居后的是6—11岁儿童,超重、肥胖率分别为6.19%和4.38%;超重、肥胖率最低的是12—17岁青少年,分别为4.44%和2.08%。城市超重、肥胖率高于农村;家庭人均年收入在贫困线以上者高于家庭人均年收入在贫困线以下者;男性高于女性。18—44岁居民腹部肥胖率为21.46%,随年龄的增长,腹部肥胖率呈上升趋势。2.铁营养状况:血红蛋白水平随年龄的增加呈上升趋势。3—5岁儿童中,男孩的血红蛋白均值低于女孩;12—17岁青少年及18—44岁成年人中,均呈现女性血红蛋白均值低于男性的趋势。随年龄的增长,贫血率呈上升趋势,尤其在进入青春期后,贫血率明显升高,3—5岁儿童、6—11岁儿童、12—17岁青少年、18—44岁成年人贫血率依次为10.32%、10.62%、15.92%、20.95%。3—5岁儿童中,男孩贫血率高于女孩;12—17岁青少年及18—44岁成年人中,女性贫血率明显高于男性。城市居民贫血率在各年龄组均低于农村居民。血清铁蛋白水平随年龄的增长呈上升趋势。3-5岁儿童中,城市儿童血清铁蛋白水平(43.71μg/L)低于农村儿童(49.21μg/L);而18-44岁成年人中,城市居民的血清铁蛋白均值(86.04μg/L)明显高于农村居民(81.77μg/L)。从性别方面来看,3—5岁儿童、6—11岁儿童均呈现出男孩血清铁蛋白水平低于女孩的特点;而12—17岁青少年及18—44岁成年人则出现相反的结果,即男性血清铁蛋白水平明显高于女性。低贮存铁率最严重的为18—44岁成年人(9.72%),其次为12—17岁青少年(4.94%)、3—5岁儿童(3.95%),最后是6—11岁儿童(2.96%)。低贮存铁率的性别差异在不同年龄段各有不同,3—5岁儿童中男孩的低贮存铁率(4.31%)高于女孩(3.53%);6—11岁儿童男女差异不明显;12—17岁青少年,女性低贮存铁率(6.77%)明显高于男性(3.29%);在18—44岁成年人中,男、女性居民低贮存铁率差异继续扩大,分别为1.47%、15.97%。影响男性低贮存铁的因素主要是生长发育的需要,而影响女性低贮存铁的因素除了生长发育的影响外,月经、怀孕、哺乳等生理状况也可能是主要影响因素。6—11岁儿童、18—44岁成年人呈现出城市居民低贮存铁率小于农村居民的特点。3.不同体质状况贫血及低贮存铁的分布规律:总体上,超重、肥胖者的贫血率低于非超重、肥胖者。儿童青少年中,肥胖组贫血率高于超重组;成年人中,贫血率随BMI增加呈下降趋势,但超重、肥胖的成年女性贫血率依然维持在较高水平,应引起重视。3—5岁儿童及6—17岁女性儿童青少年中,低贮存铁率随BMI增加呈上升趋势,超重、肥胖组的低贮存铁率高于低体重组和体重正常组。6—17岁男性儿童青少年及18—44岁成年人中,低贮存铁率在不同BMI分组中未见明显的变化规律。4.超重、肥胖与铁营养状况的相关性分析:超重、肥胖与血红蛋白值多呈正相关,发生贫血的危险性较低。而3～5岁儿童、6～17岁女性儿童青少年中,超重、肥胖者更易出现血清铁蛋白减少,即低贮存铁。以BMI正常组为对照,调整年龄、性别及城乡因素,分析发现3～5岁儿童中,超重、肥胖者患贫血的危险性较体重正常者小,OR值分别为0.69(0.54—0.89)、0.89(0.69—1.15):但超重、肥胖者患低贮存铁的危险性增大,OR值分别为1.50(1.09—2.05)、1.46(1.02—2.10)。6～11岁儿童、12～17岁青少年及18～44岁成年人中超重、肥胖者患贫血的危险性均较体重正常者减小;成年人中肥胖者患低贮存铁的危险性降低,OR值为0.81(0.67—0.98),而其他年龄组超重、肥胖与低贮存铁未见明显相关。5.超重、肥胖者贫血及低贮存铁的影响因素:社会经济因素,如农村居民、家庭人均年收入低于贫困线、文化程度低、女性青少年及成年女性等是我国超重、肥胖居民贫血及低贮存铁的主要影响因素。生长迟缓对3～5岁儿童患贫血是一个危险因素,OR值为2.93(1.98—4.35);成年人中静态生活时间大于等于5小时/天、腹部肥胖者患贫血及低贮存铁的危险性减小。膳食因素在超重、肥胖与贫血及低贮存铁的关系中未能提供充足证据。结论:贫血及超重、肥胖在我国3～44岁居民中有较高的患病率。其中农村居民、小年龄儿童、女性青少年和成年女性是贫血及低贮存铁的高发人群。3～44岁各年龄组中超重、肥胖与血红蛋白均呈正相关。儿童青少年中,肥胖组贫血率高于超重组,但均低于低体重组和体重正常组;成年人中,低体重组、体重正常组、超重组、肥胖组的贫血率依次降低。3～5岁儿童、6～17岁女性儿童青少年的低贮存铁率随BMI的增加而升高,即超重、肥胖者更易出现血清铁蛋白减少。6～17岁男性儿童青少年及18～44岁成年人中,未见低贮存铁率与BMI的明显关系。社会经济因素,如农村居民、家庭人均年收入低于贫困线、文化程度低等是我国超重、肥胖居民贫血及低贮存铁的主要影响因素。膳食因素在超重、肥胖与贫血及低贮存铁的关系中未能提供充足证据。更多还原

【Abstract】 BackgroundAnemia and obesity are two of the most common nutritional disorders among Chinese population,and iron deficiency is considered to be the primary cause of anemia.Researchers have been thinking that iron deficiency is induced by under-nutrition and is more prevalent in infants,pregnant and feeding women, adolescent girls and elders,while the relation of overweight,obesity and iron deficiency has not been explored well.Researches on obesity and iron deficiency concluded different results,and few representative studies on obesity and iron deficiency was reported in China.ObjectiveTo assess status and the risk factors of iron deficiency and anemia in overweight and obesity populations,compared with normal weight population,using data of 2002 China National Nutrition and Health Survey.Relation between obestisy and iron deficiency was explored as well.MethodSample were from 2002 China National Nutrition and Health Survey,Analyses were limited to people aged 3 to 44 years old(129,191),in which pregnant and feeding women,as well as individuals without Hb values were excluded.Four groups were derided according to age,namely 3- to 5-year-old children(11945),6- to 11-year-old children(30413),12- to 17-year-old adolescents(17784) and 18- to 44-year-old adults(69049).Variables included demograpic features,body mass levels,anemia and iron deficiency status,dietary indexes and physical activity level.ANOVA,χ~2 test,pearson correlation,logsitic regression and factor analysis were used.Results1.Overweight and obesity:18- to 44-year-old adults demonstrated the highest prevalence of overweight(22.86%) and obesity(6.57%);12- to 17-year-old adolescents showed the lowest prevalence of overweight(4.44%) and obesity(2.08%);prevalence of overweight and obesity among 3- to 5-year-old children(8.88%,6.80%) and 6- to 11-year-old children(6.19%,4.38%) were at middle levels.Overweight and obesity were more prevalent in urban areas,population above poverty level,male individuals. Prevalence of abdominal obesity is 21.46%among adults,increasing with age.2.Iron status:Hb was found increasing with age,which was lower in boys than girls among 3- to 5-year-old children,however,higher in males than females among 12- to 17-year-old adolescents and 18- to 44-year-old adults.Anemia demonstrated the similar upward trend with age increase(10.32%,10.62%,15.92%,20.95%,respectively from children to adults).Females and rural individuals seemed to be at higher risk of anemia.Serum ferritin was higher in elder individuals.Urban children had lower serum ferritin level(43.71μg/L) than rural children(49.21μg/L);while urban adults had significantly higher serum ferritin level(86.04μg/L) than rural adults(81.77μg/L). Children either 3- to 5-year-old or 6- to 11-year-old demonstrated that girls had higher serum ferritin level than boys,while adolescents and adults implied that female had lower serum ferritin.The highest prevalence of iron deficiency defined by serum ferritin occurred in adults group(9.72%),the following groups were adolescents (4.94%),3- to 5-year-old children(3.95%),6- to 11-year-old children(2.96%).Boys of 3- to 5-year-old children had higher prevalence of iron deficiency than girls,while that of femal adolescents and adults were higer than males.The results suggested that growth need was the main risk factor for male iron deficiency,while catamenia, pregnant,feeding as well as growth were the risk factors for female iron deficiency. Iron deficiency rate in urban areas was lower than that in rural areas among adolescents and adults.3.Anamia and iron deficiency in different body mass levels:Overweight and obesity individuals demonstrated lower prevalence of anemia than underweight and normal weight groups.It was noticed that obesity children and adolescents were at higher risk for anemia than overweight children and adolescents. Though prevalence of anemia in adults decreased as BMI increased,we should also notice that overweight and obesity female adults had a high level of anemia.Prevalence of iron deficiency increased as BMI increase from underweight to normal weight to overweight and to obesity in 3- to 5-year-old children and girls in 6-to 17-year-old children and adolescents.The same trend wasn’t found in adults and boys in 6- to 17-year-old children and adolescents.4.Correlation of obesity and iron status:There was a positive correlation between obesity and Hb value among all groups.Negative correlations were found in 3- to 5-year-old child and girls of 6- to 17-year-old children and adolescents.Logistic regression was used to estimate the independent association between iron status and obesity,control age,gender and area,made normal weight as control group.It was noted that overweight and obesity children aged 3 to 5 had a significantly increased risk of iron deficiency,with odds ratio at 1.50(1.09-2.05), 1.46(1.02-2.01),respectively,while a decreased risk for anemia,with odds ratio at 0.69(0.54-0.89),0.89(0.69-1.15),respectively.Overweight and obesity individuals had a lower risk for anemia among 6- to 11-year-old children,12- to 17-year-old adolescents and 18- to 44-year-old adults.Obesity adults had a decreased risk for iron deficiency with odds ratio at 0.81(0.67-0.98).Significant correlation wasn’t found between obesity and iron status among other groups.5.Risk factors for anemia and iron deficiency in overweight and obesity population:Social-economic factors,such as rural area,income below poverty,low grade of education,female adolescents and adults were major risk factors for anemia and iron deficiency in overweight and obesity population.Growth retardation was a risk factor for anemia in 3- to 5-year-old children,with odds ratio at 2.93(1.98-4.35).Overweight and obesity adults with static life time≥5h/d or abdominal obesity had a decreased risk for anemia and iron deficiency.Dietary fators didn’t account for the relation between obesity and iron deficiency.ConclusionsPrevalence of anemia and obesity were at high level among 3- to 44-year-old population in China.Rural individuals,younger children,female adolescents and adults were risk groups for anemia and iron deficiency.There was a positive correlation between obesity and Hb.In children and adolescent groups,obesity individuals had a higher prevalence of anemia than overweight ones,both of which were lower than underweight and normalweight children and adolescents.Among adults population,prevalence of anemia decreased from underweight to normalweight to overweight to obesity groups.Overweight and obesity groups of 3- to 5-year-old children and girls in 6- to 17-year-old children and adolescents were at higher risk for iron deficiency,compared with underweight and normalweight groups.The same trend wasn’t found in adults and boys in 6- to 17-year-old children and adolescents.Social-economic factors accouted for anemia and iron deficiency in Chinese overweight and obesity population aged 3 to 44.Dietary effects in relation of obesity and iron status weren’t supported sufficiently.更多还原