儿童血浆鸢尾素与肥胖关系的队列研究

  目的  探究儿童血浆鸢尾素(Irisin)与肥胖相关指标变化值和新发肥胖的纵向关联，以及体力活动(physical activity, PA)和静态行为(sedentary behavior, SB)是否存在调节作用，为儿童肥胖防治工作提供科学依据。  方法  采用整群随机抽样的方法，于2017年在广州市随机抽取5所小学521名儿童进行问卷调查和体格检查，并于2019年随访。根据基线问卷的PA和SB信息筛选符合标准(SB≥同年龄、性别P₇₅或 < 同年龄、性别P₂₅；且中高等强度PA≥60 min/d或 < 150 min/周)的儿童进行血浆Irisin测量。分别采用多重线性回归和Logistic回归进行关联性分析。  结果  儿童2年内肥胖、超重及肥胖、中心性肥胖的累计发病率分别为2.82%，6.57%，6.81%。儿童血浆Irisin与肥胖相关指标变化值、新发超重肥胖或中心性肥胖的关联均无统计学意义(P值均>0.05)。以PA水平分层后，低PA组中Irisin水平与体重变化值呈正相关(B=0.229，P=0.03)；以SB水平分层后，低SB组中Irisin水平与身高变化值呈正相关(B=0.210，P < 0.05)。PA和SB均对Irisin与体重变化值有调节作用(P_PA调节=0.01，P_SB调节=0.05)。  结论  PA和SB对儿童血浆Irisin与体重增加值具有调节作用，未发现Irisin与儿童新发超重或肥胖相关。

Association of plasma irisin concentration with obesity among children: a cohort study

  Objective  To explore the longitudinal association of the levels of plasma irisin among children with changes in obesity related parameters and newly-onset obesity, and to explore whether physical activity (PA) and sedentary behavior(SB) have regulatory effects, to provide a scientific basis for the prevention and control of childhood obesity work.  Methods  Cluster random sampling method was used to select 521 children from five schools in Guangzhou in 2017 at baseline and were followed up in 2019. A based on baseline PA and SB, children who meet the following criterion were selected: moderate-vigorous intensity PA≥60 min/d or < 150 min/week; and gender-, age-specific SB≥P₇₅ or SB < P₂₅. Plasma irisin concentration was measured in all the selected children. Multiple linear regression and Logistic regression were conducted to analyze the association.  Results  The two-year cumulative incidence of obesity, overweight and obesity, and central obesity was 2.82%, 6.57%, and 6.81%, respectively. There was no statistically significant association between plasma irisin levels and changes in obesity-related parameters, newly-onset overweight obesity or central obesity among children (P>0.05). After stratified by PA, the irisin concentration in the low PA group was positively associated with weight change (B=0.229, P=0.03). After stratified by SB, the irisin concentration in the low SB group was positively associated with the height change (B=0.210, P < 0.05). In addition, PA level and SB level both had a moderating effect on the association between plasma irisin levels and the weight change (P_PA=0.01, P_SB=0.05).  Conclusion  PA and SB show moderating effect on plasma irisin concentration and weight gain. No association of irisin concentration with newly-onset overweight or obesity among children has been found.