【作者】 关玉明；

【导师】 桂永浩；

【作者基本信息】 复旦大学 ， 儿科学， 2004， 博士

【摘要】 第一部分:肥胖的流行病学调查及危险因素分析目的 调查上海儿童肥胖发病率,探讨导致儿童肥胖的危险因素。 方法 采用整群随机抽样,横断面调查上海市徐汇区六所中小学5425名学生,测量身高、体重,计算体重指数。应用标准问卷调查儿童饮食习惯,运动锻炼,父母、祖父母及外祖父母的体形和糖尿病、高血脂以及心脑血管疾病史,母亲饮食行为。肥胖的定义采用根据国际大样本人群资料确定的体重指数标准(国际肥胖工作小组提出的分年龄、性别BMI临界值)。 结果 上海市徐汇区6~14岁中小学生肥胖检出率为5.5%.超重检出率为18.6%,肥胖和超重呈男性高于女性,呈小年龄组显著高于高年龄组。肥胖儿童表现为过度饮食和缺少活动。父母亲肥胖、高出生体重儿童易患肥胖。肥胖儿童母亲与非肥胖儿童母亲饮食行为有显著差别。 结论 本组儿童肥胖发病率高,过度饮食和缺少活动是引起肥胖的主要原因。肥胖有家庭集聚趋势,父母肥胖儿童易患肥胖,母亲饮食行为对儿童肥胖有重要影响。第二部分:肥胖儿童心血管疾病危险因素分析一、血液生化检查目的 了解肥胖儿童血脂、脂蛋白、胰岛素的分布特征,探讨肥胖儿童心血管疾病的代谢危险因素。 方法 对155名肥胖儿童和145名正常体重儿童进行空腹血糖、胰岛素、甘油三脂、胆固醇、低密度脂蛋白、高密度脂蛋白、载脂蛋白A-I、载脂蛋白B检测。 结果 肥胖儿童与非肥胖儿童相比,空腹胰岛素、甘油三脂、低密度脂蛋白、载脂蛋白B显著增高,胰岛素与血糖比、低密度脂蛋白与高密度脂蛋白比显著增高,载脂蛋白A与载脂蛋白B比值显著降低。 结论 肥胖儿童存在明显的动脉粥样硬化性心血管疾病危险因素。二、脂蛋白酯酶基因多态性分析 <WP=5>目的 了解脂蛋白酯酶基因外显子常见突变与肥胖儿童心血管疾病危险因素的关系。 方法 用聚合酶链反应加限制性片段长度多态性检测脂蛋白酯酶外显子常见的三个突变位点D9N、N291S和S447X,同时检测血脂。比较肥胖儿童与非肥胖儿童基因突变率的差异,以及不同基因型血脂的分布差异。 结果 332名肥胖及非肥胖儿童中未检测出D9N和N291S突变,S447X突变在肥胖与非肥胖儿童中分布无明显差异,S447与X447两种基因型间血脂无明显差异。 结论 我国儿童D9N与N291S基因突变率低,S447X突变对肥胖儿童心血管危险因素可能影响不大。第三部分:肥胖儿童心功能检测一、肥胖儿童心率变异性分析目的 了解肥胖儿童心率变异性的特征 方法 用Holter对62例单纯性肥胖儿童和61例非肥胖儿童连续记录24小时心电信号,进行心率变异性分析 结果 肥胖儿童心率变异性的频域指标:窦性心律RR间期标准差(SDNN)和相邻窦性心律RR间期差的均方根(rMSSD)低于非肥胖儿童;频域指标:高频功率(HF)和低频功率(LF)低于非肥胖儿童。结果有统计学意义 结论 肥胖儿童心率变异性减小,迷走神经功能降低。二、肥胖儿童平板运动试验目的 评价肥胖儿童运动能力,运动时心率改变。 方法 用改良Bruse方案对213名正常体重儿童、56名超重儿童和106名肥胖儿童进行平板运动试验,比较分析肥胖儿童运动能力、运动对心率及血压影响。 结果 运动耐受时间男孩长于女孩,肥胖儿童明显短于非肥胖儿童,运动耐受时间与体重指数成反比;肥胖儿童收缩压明显高于非肥胖儿童,终止运动即刻收缩压高于非肥胖儿童,血压增加幅度亦高于非肥胖儿童,收缩压随体重指数增大而增高;肥胖儿童运动所达到的最大心率降低。 结论 肥胖儿童有明显的高血压表现,运动能力下降。三、超声心动图评价肥胖儿童心脏结构和功能目的 探讨儿童单纯性肥胖对于心脏结构和功能的影响。 方法 应用超<WP=6>声心动图测定98例6~15岁单纯性肥胖儿童和85例正常体重儿童左心室结构、左心室收缩功能与舒张功能、右心室舒张功能参数。分析两组间参数差别。 结果 肥胖儿童比非肥胖儿童:1、左心室舒张末径、左心室收缩末径有增大趋势,但无统计学意义,主动脉内径、左心室质量显著增大,左心室质量指数无差别,标化左心室质量明显增大,并与体重指数正相关。2、左心室短轴缩短率、环周缩短率、左室射血分数有降低趋势,但无统计学意义,每搏量、心输出量无明显差别,但心搏指数、心脏指数、主动脉流速积分、主动脉最大血流速度降低。3、左心室等容舒张时间,二尖瓣E峰、二尖瓣A峰、E/A比值无明显差别,但E峰流速积分、A峰流速积分降低。4、三尖瓣E峰、三尖瓣A峰、E/A比值无明显差别,但E峰流速积分、A峰流速积分降低。 结论 肥胖儿童心脏结构有明显改变,心功能有降低的趋势。更多还原

【Abstract】 Part OneEpidemiological investigation of obesity and assessment of risk factors in children aged 6~14 years in Xuhui district, Shanghai Objective To investigate the prevalence of obesity in children aged 6~14 years in one of local districts in Shanghai, to evaluate risk factors associated with childhood obesity. Methods With cluster sampling, 5425 children aged 6~14 years were selected randomly, measurement of height and weight was taken to calculate body mass index, standard structured questionnaire was used to investigate children’s eating habits, physical exercise habits, familial cardiovascular disease history and mothers` eating behavior. A child was defined as being obese or overweight according to a standard definition for child overweight and obesity based on an international survey of six large nationally representative cross sectional growth studies(BMI cutoff values of International Obesity Task Force). Results On average, the prevalence of obesity was 5.5%(7.8% in male, 3.2% in female), with prevalence of overweight 8.6%(22.9% in male, 14.6% in female). The prevalence of obesity was higher in younger children than in older children. Obesity was correlated with excess eating, lack of physical activity, obese parents, born weight and mother’s eating behavior. Conclusion the prevalence of overweight is higher in children aged 6~14 years old, and tends to increase gradually. Excess eating and lack of physical activity are main causes of obesity. Mother’s eating behavior has a significant impact on child obesity. The probability of obesity in children may increase in the presence of obesity in the child’s parents. Part Two <WP=8>Assessment of high risk factors for cardiovascular diseases in obese childrenⅠ Biochemical examinationObjective To investigate the profile of plasma lipid, lipoprotein, glucose and insulin to explore high risk factors of cardiovascular diseases in children with simple obesity. Methods The study group consisted of 255 simple obese children. Control group consisted of 145 healthy children. Glucose, insulin, triglyceride, total cholesterol, high density lipoprotein cholesterol, low density lipoprotein cholesterol, apolipoprotein A-I and B levels were measured. Results The level of insulin, triglyceride, low density lipoprotein cholesterol and apolipoprotein B were significantly higher in obesity group than in control group. The ratio of insulin to glucose and LDL to HDL was significantly higher in obesity group than in control group. The ratio of apolipoprotein A-I to B was significantly lower in obese children than in controls. Conclusion Simple obese children present significant insulin resistance and disturbances in lipid metabolism, manifested by increased serum triglyceride, low density lipoprotein cholesterol and apolipoprotein B. Unfavourable lipid metabolism and insulin resistance may be high risk factors for atherosclerosis.Ⅱ Evaluation of single nucleotide polymorphisms oflipoprotein lipase gene in simple obese childrenObjective This study inquired into the relationship between lipoprotein lipase (LPL) gene D9N, N291S and S447X polymorphisms and risk factors of cardiovascular disease in obese children. Methods The polymerase chain reaction (PCR) and restriction fragment length polymorphism(RLFP) techniques were used to detect the three common mutation of LPL gene exon D9N N291S and S447X in 157 obese children and 175 normal controls. The levels of the plasma lipid and lipoprotein were also measured. Results The D9N and N291S gene mutation were not detected in two groups. There was no significant difference in the frequency of S447 gene mutation between obese group and control group. There is no significant difference in the levels of the plasma lipid and lipoprotein between children with S447 genotype and children with X447 genotype. Conclusion The frequency of <WP=9>D9N and N291S gene mutation is low in Chinese children. It is possible that S447X gene mutation does not play an important role in the development o更多还原