Secular trend of BMI and its consistency with self-rated BMI status among Chinese children and adolescents

Abstract

Objective To describe the secular trend of BMI and its consistency with self-rated BMI status in Chinese children and adolescents, and to further investigate the related factors affecting self-rated BMI, su as to provide a scientific reference for interventional measures.

Methods A total of 6 238 children and adolescents aged 6–18 years were selected according to date from Chinese Health and Nutrition Svrvey during 2000–2015 and the criteria from National Health Commission of China. The Lambda-Mu-Sigma method (LMS) and Kappa consistency test were, respectively, applied to describe the percentiles for BMI and its agreement with self-rated BMI status. Multinomial Logistic model was used to assess the related factors influencing self-rated BMI status.

Results P ₅₀ and P ₈₅ percentiles showed an increasing trend, especially the increase of high percentile of BMI. Regardless of age and sex, the measured and self-rated BMI showed low agreement. More than 50% of over-weighted or underweighted children perceived themselves as normal-weight, and about 1/4 of normal weight students misclassified themselves as abnormal in weight. Urban buys were more likely to evaluate themselves as underweight [ OR(95% CI) = 1.43 (1.18-1.73) ]. Buys who favored popular showed [ OR(95% CI) = 1.80 (1.23-2.55) and cartoon [ OR(95% CI) = 1.39 (1.00-1.96)] were more likely to consider themselves as overweight. Girls in the older age group [ OR (95% CI) =2.74 (2.08-3.61)] and urban [1.53 (1.21-1.94)] who favored popular programs [ OR (95% CI) = 1.74 (1.27-2.38)] were more likely to perceived themselves as overweight. But girls who like anime/cartoons were more likely to think they were underweight [ OR(95% CI) = 1.78 (1.33-2.40)].

Conclusion The trend of BMI has shown an increasing trend in the past decade and it demonstrated a large bias with perceived BMI. Age, area and type of video were significant factors that influenced the self-rated BMI status.

Abstract

【摘要】 目的 分析中国儿童青少年体质量指数 (BMI) 变化趋势与自评 BMI 的一致性及影响自评 BMI 的相关因素, 以期为相应干预措施的制定提供科学依据。 方法 以“中国健康与营养调查”2000—2015 年 6 轮调查资料中 6 238 名 6~ 18 岁儿童青少年作为研究对象, 采用偏度-均值-־变异系 (LMS) 法揭示 BMI 变化规律, 采用妒检验和Kappa —致性检验 评价其与自评体重的偏差, 采用多元 Logistic 回归模型分析影响体型自我评价的相关因素。 结果 2000—2015 年儿童青 少年 BMI 百分位数曲线 P ₅₀ 和 P ₈₅ 均显示增高趋势, 且高百分位增幅更大。无论年龄和性别, 实测 BMI 与自评体重一致性 较差 ( Kappa<0.3), 50% 以上的消瘦和超重 (除 13~18 岁女生) 调查对象误认为自身体重正常, 约 1/4 体重正常调查对象误 以为自身体重异常。城市男生更易自评体重偏瘦 [ OR 值 (95% CI)=1.43(1.18~1.73)], 喜欢流行节目 [ OR 值 (95% CI)= 1.80(1.23~2.55)] 和卡通/动漫 [ OR 值 (95% CI)= 1.39 (1.00~1.96)]的男生更易自评体重超重。高年龄组 [ OR 值 (95% CI)= 2.74(2.08~3.61)]、城市 [ OR 值 (95% CI)= 1.53(1.21~1.94)]、喜欢流行节目 [ OR 值 (95% CI)= 1.74(1.27~2.38)] 的 女生更易自评体重超重;喜欢动漫/卡通节目的女生更会认为自身体重偏瘦 [ OR 值 (95% CI)= 1.78 (1.33~2.40)]。 结论 过去十多年来中国儿童青少年 BMI 呈现升高趋势, 且与自评 BMI 偏差较大, 年龄、现住地和喜欢视频节目类型会影响体重 的自我评价。