Impact of Disease Status and Physical Acitivity on Heart Rate Variability in Children with Type 1 Diabetes

• Main Authors: Su-Ru Chen, 陳淑如
• Other Authors: Chii Jeng
• Format: Others
• Language: zh-TW
• Published: 2007
• Online Access: http://ndltd.ncl.edu.tw/handle/22745288786969882022

博士 === 臺北醫學大學 === 醫學研究所 === 96 === Autonomic neuropathy is one of the major complications of diabetes, and is associated with morbidity and mortality of diabetes. Obesity is a high risk factor of type 2 diabetes. Heart rate variability (HRV) has been used to assess the dysfunction of autonomic nervous system. Reduced HRV reflects autonomic imbalance and has been shown to be an independent predictor of mortality in various patient population. Most of the studies focused on the differences of HRV between type 1 diabetic and healthy children, and attributed the autonomic neuropathy of diabetes to the effects of hyperglycemia. However, the influences of other factors on the autonomic nervous function in diabetic children are little known. The purpose of the research is to explore the impact of disease status on HRV in type 1 diabetes, and to explore the influence of physical activity on HRV in type 1 diabetes and healthy children. The influences of physical activity on HRV in obese and healthy children were also studied. This is a cross-sectional study using purposive sampling which includes type 1 diabetic children, obese children, and healthy control children. A total of 93 type 1 diabetic children, 88 obese children, and 107 healthy children were recruited. Electrocardiography was used to measure HRV both in resting state and active state. Physical activity questionnaire for children was adopted to explore their average physical activity. The results showed that: type 1 diabetic children had significant lower LnLF, LnHF, and LnTP than those of healthy children. Glycosylated hemoglobin and disease duration are two factors that affecting HRV in type 1 diabetes. Only children with poor glycemic control and extended disease duration will manifest autonomic neuropathy. Obese children had significant lower LnHF and LnTP, but similar LnLF, LnLF/HF than those of healthy children. When proceeding from resting state to active state, there was consistent decrease of LnLF, LnHF, and LnTP for all the study groups. However, the response of HRV during exercise differed from the responses of HRV at rest. Diabetic children with low physical activity have a HRV significantly lower than healthy control. However, the HRV among patients with moderate activity, high activity, and the healthy control were not different. The increase of physical activity was associated with an improvement of autonomic nervous function in obese children. We concluded that hypoglycemic control may help prevent the decrease of HRV in type 1 diabetes. Type 1 diabetes and obese children had significant lower HRV than those of healthy children. The increase of physical activity was associated with an improved HRV in type 1 diabetes and obese children, especially activity with moderate intensity.