Heart Rate Variability in Taiwanese Obese Children

臺灣肥胖兒童的心率變異性

傳振宗(Chen-Chung Fu) ； 李燕嗚(Yin-Ming Li) ； 裴馰(Dee Pei) ； 陳健麟(Chien-Lin Chen) ； 駱惠銘(Huey-Ming Lo) ； 吳篤安(Du-An Wu) ； 郭博昭(Terry-Bj Kuo)

《慈濟醫學雜誌》 18卷3期 (2006/06) Pp. 199-204

https://doi.org/10.6440/TZUCMJ.200606.0199

摘要

目的：探討肥胖兒童早期的心率變異性的變化。材料與方法：我們在91年針對花蓮市全部公立國中1,826名學生進行肥胖評估，初步調查總共有1,724名(94.4%)參加，然後依據衛生署91年發布青少年以身體質量指數所訂定的肥胖標準，分層抽樣選出225位正常、過重與肥胖學童邀請參加心率變異性與生化抽血檢查三組。結果：共有170位（81位正常、33位過重與55位肥胖）學童參加，結果發現肥胖學童的身體質量指數、HOMA-IR、收縮壓與舒張壓明顯大於正常體位學童，此外，肥胖學童的心率變異性檢查結果，代表副交感神經控制的高頻(HF)在肥胖男、女學童都明顯降低而代表交感神經調控的低頻（LF%與LF/HF比值）在肥胖男學童有意義增加，而女學童的交感神經調控亦呈現增加，雖然沒有統計上意義。多變項分析顯示身體質量指數與心跳數和HF為負相關，和LF%與LF/HF比值為正相關，同時男童比女童有較高的LF%與LF/HF比值。結論：肥胖兒童有胰島素阻抗與心臟的自律神經異常，包括副交感神經的控制在男、女學童降低，且肥胖男學童的交感神經調控增加。此外，男童比女童有較高的交感神經調控。

關鍵字

肥胖兒童 ； 心率變異性 ； 自律神經功能異常

並列摘要

Objective: The primary purpose of the present community-based study was to investigate early changes in cardiac autonomic function in obese children. Materials and Methods: A survey of juvenile obesity in Hualien in eastern Taiwan was performed in 2002. A total of 1,724 adolescents who were 12 or 13 years old were recruited. The overall prevalences of normal weight, overweight and obese adolescents were 71.5% 13.1%, and 15.4%, respectively. A stratified random sampling scheme was performed. We selected 100, 50 and 75 subjects from the above-mentioned three groups, and invited them to join this study. Totally, 170 students (normal-weight: overweight: obese=81:34:55) participated in this study. They received blood checks and a heart rate variability (HRV) examination. The homeostasis model assessment of insulin resistance (HOMA-IR) was used to evaluate insulin sensitivity. Results: Compared with the normal-weight group, the obese children had significantly elevated body mass indexes (BMI), HOMA-IR, and systolic and diastolic blood pressure levels. In addition, compared to their normal weight counterparts, obese children had significantly reduced high-frequency power (HF) but elevated low-frequency power in normalized units (LF%), and elevated ratios of low-frequency power to high-frequency power (LF/HF ratio). Further analyses revealed that compared with the normal weight counterparts; obese boys had significantly reduced HF but elevated LF % and LF/HF ratios. Among obese girls, the HF was reduced significantly, and LF% and the LF/HF ratio were increased, though not significantly. In stepwise multiple regression analysis, the BMI and heart rate were negatively associated with the HF component and positively associated with the LF/HF ratio and LF%. For every 1kg/m^2 increment in the BMI, the LF/HF ratio and LF% components of HRV increased ln(0.02) and 0.42% respectively, while HF decreased 0.03 ln(ms^2). Boys had a higher LF/HF ratio and LF% than girls. Conclusions: The obese boys and girls had increased insulin resistance and changes in autonomic nervous function that included reduced parasympathetic control and obese boys had elevated sympathovagal modulation. Gender-related autonomic differences, such as girls having lower sympathetic modulations of HRV, were also noted.

並列關鍵字

obese children ； heart rate variability ； autonomic nerve dysfunction