肥胖、超重、BMI正常患者腹部脏器及腹部肌肉异位脂肪堆积的MRI定量分析

MRI Quantitative Analysis of Ectopic Fat Accumulation in Abdominal Organs and Muscles of Obese, Overweight, and BMI Normal Patients

摘要: 目的：肥胖的定义是身体质量指数(BMI)超过28 kg/m²，近年来肥胖人数日益增加，肥胖已成为一个严重的健康问题。本研究的目的是定量分析肥胖、超重和正常BMI患者腹部脏器及腹部肌肉异位脂肪堆积的差异以及较为敏感的部位。材料与方法：纳入华北理工大学附属医院接受腹部核磁共振检查的226名连续患者，他们接受了BMI计算的标准临床评估。BMI肥胖者92例，BMI超重者62例，BMI正常者72例。所有对象均进行了上腹部3.0T MRI mDixon序列扫描，分别测量肝脏、胰腺、脾脏、肾脏、第三腰椎体水平腰大肌、竖脊肌、多裂肌脂肪含量，以及测量内脏脂肪面积(VFA)和皮下脂肪面积(SFA)。结果：肝脏FF值、胰腺FF值、肾脏FF值、腹部肌肉FF值、VFA及SFA在肥胖组、超重组和BMI正常组两两之间都具有统计学意义(P < 0.05)。脾脏FF值在肥胖组、超重组和BMI正常组两两之间没有统计学意义(P > 0.05)。相关性分析显示，年龄和性别对腹部脏器和腹部肌肉异位脂肪堆积存在一定的相关性。校正年龄和性别之后，多因素分析显示，在肥胖、超重和BMI正常组中，胰腺FF值(OR = 1.32, P < 0.05)、腰大肌FF值(OR = 1.66, P < 0.05)、多裂肌FF值(OR = 1.88, P < 0.05)、VFA (OR = 1.04, P < 0.05)、SFA (OR = 1.02, P < 0.05)都具有统计学意义，提示这些指标和BMI界定的肥胖、超重和正常组具有一定的相关性，对肥胖有一定的提示作用。结论：肥胖患者易在腹部脏器、腹部肌肉及皮下出现脂肪沉积；胰腺和腹部肌肉的脂肪异位沉积对肥胖的发生发展更为敏感。

Abstract: Objective: The definition of obesity is a body mass index (BMI) exceeding 28 kg/m². In recent years, the number of obese people has been increasing, and obesity has become a serious health problem. The purpose of this study is to quantitatively analyze the differences and sensitive areas of ectopic fat accumulation in abdominal organs and muscles among obese, overweight, and normal BMI patients. Materials and Methods: 226 consecutive patients who underwent abdominal MRI examination at the Affiliated Hospital of North China University of Science and Technology underwent standard clinical evaluation based on BMI calculation. There were 92 cases of BMI obesity, 62 cases of BMI overweight, and 72 cases of BMI normal. All subjects underwent a 3.0T MRI mDixon sequence scan of the upper abdomen, measuring the fat content of the liver, pancreas, spleen, kidneys, and third lumbar vertebrae at the level of the lumbar muscle, erector spinae muscle, and multifidus muscle, as well as measuring visceral fat area (VFA) and subcutaneous fat area (SFA). Results: The liver FF value, pancreas FF value, kidney FF value, abdominal muscle FF value, VFA, and SFA all showed statistical significance (P < 0.05) among the obese group, overweight group, and BMI normal group. There was no statistically significant difference in spleen FF values between the obese group, the overweight group, and the BMI normal group (P > 0.05). Correlation analysis shows that age and gender have a certain correlation with ectopic fat accumulation in abdominal organs and muscles. After adjusting for age and gender, multivariate analysis showed that in the obese, overweight, and BMI normal groups, pancreatic FF value (OR = 1.32, P < 0.05), lumbar muscle FF value (OR = 1.66, P < 0.05), multifidus FF value (OR = 1.88, P < 0.05), VFA (OR = 1.04, P < 0.05), and SFA (OR = 1.02, P < 0.05) all had statistical significance, indicating a certain correlation between these indicators and the BMI-defined obese, overweight, and normal groups, which has a certain suggestive effect on obesity. Conclusion: Obese patients are prone to fat deposition in abdominal organs, abdominal muscles, and subcutaneous tissue; the ectopic deposition of fat in the pancreas and abdominal muscles is more sensitive to the occurrence and development of obesity.