MR定量分析肝脏和胰腺脂肪含量与非酒精性脂肪性肝病关系的应用研究

Application research of MR quantitative analysis in the relationships between LFF and the NAFLD,and between PFF and the NAFLD

目的:探讨MR脂肪定量技术分析肝脏脂肪含量值(LFF)和胰腺脂肪含量(PFF)与非酒精性脂肪性肝病(NAFLD)严重程度及肝功能的关系。方法:选取医院收治的185例接受MR全肝脏mDIXON序列扫描的患者,测量LFF及PFF,并根据肝脏脂肪分数图(FF)将其分为NAFLD组(160例)和对照组(25例)。比较两组患者体质量指数(BMI)、丙氨酸转氨酶(ALT)、甘油三酯(TG)、空腹血糖(FBG)、低密度脂蛋白(LDL-c)、高密度脂蛋白(HDL-c)、LFF和PFF,采用Spearman分析法分析LFF和PFF与各指标的相关性;采用Logistic回归分析法分析NAFLD严重程度的影响因素。结果:NAFLD组160例患者中轻度72例(LFF为5.1%~14.0%),中度76例(LFF为14.1%-28.0%),重度12例(LFF>28.0%);对照组25例患者LFF均正常。NAFLD组与对照组LFF、PFF及BMI比较,差异均有统计学意义(t=17.259,t=9.058,t=7.430;P<0.05),ALT、TG、FBG、LDL-c及HDL-c指标比较,差异均有统计学意义(t=6.591,t=3.957,t=3.267,t=2.112,t=-3.727;P<0.05)。轻度、中度和重度患者的LFF、PFF及BMI比较,差异均有统计学意义(F=21.944,F=16.391,F=5.872;P<0.05),ALT、TG、FBG、LDL-c及HDL-c指标比较,差异均有统计学意义(F=30.240,F=3.984,F=3.863,F=3.398,F=1.214;P<0.05)。BMI、ALT、TG、FBG与NAFLD患者的LFF和PFF均呈明显正相关(rLFF=0.31,r=0.52,r=0.33,r=0.35;rPFF=0.30,r=0.36,r=0.27,r=0.29;P<0.05),与HDL-c呈明显的负相关(r=-0.16,r=-0.3;P<0.05)。多因素Logistic回归分析结果显示,HDL-c是NAFLD严重程度的独立保护因素(OR=0.004,P<0.05),LFF、PFF、BMI、ALT、TG及LDL均为NAFLD严重程度的独立危险因素(OR=2.252,OR=1.988,OR=1.404,OR=1.196,OR=1.025,OR=5.150;P<0.05)。结论:LFF和PFF与NAFLD严重程度及肝功能指标有密切关系,LFF和PFF的升高是NAFLD加重的独立危险因素,采用MR定量分析LFF和PFF对临床监测NAFLD严重程度及肝功能具有一定的指导意义。

Objective:To explore the application of magnetic resonance(MR)quantitative analysis technique of fat in analyzing the relationships between liver fat fraction(LFF)and pancreatic fat fraction(PFF)and the severity of nonalcoholic fatty liver disease(NAFLD),and between them and liver function.Methods:A total of 185 patients who received MR whole-liver mDIXON sequence scan were selected,and their LFF and PFF were measured.They were divided into NAFLD group(160 cases)and control group(25 cases)according to the fat fraction(FF)of liver.The body mass index(BMI),alanine aminotransferase(ALT),triglycerides(TG),fasting blood glucose(FBG),low-density lipoprotein(LDL-c),high-density lipoprotein(HDL-c),LFF and PFF between two groups were compared.Spearman analysis method was adopted to analyze the correlation between LFF and various indicators,and between PFF and various indicators.Logistic regression analysis was used to analyze the influencing factors of NAFLD severity.Results:In 160 patients of NAFLD group,72 cases were mild degree(LFF WAS 5.1%-14.0%),and 76 cases were moderate degree(LFF was 14.1%-28.0%),and 12 cases were severe degree(LFF>28.0%).There were significant differences in LFF,PFF and BMI between NAFLD group and control group(tLFF=17.259,tPFF=9.058,tBMI=7.430,P<0.05),and the differences of ALT,TG,FBG,LDL-c and HDL-c between two groups also were significant(t=6.591,t=3.957,t=3.267,t=2.112,t=-3.727,P<0.05),respectively.There were significant differences in LFF,PFF,BMI,ALT,TG,FBG,LDL-c and HDL-c among mild group,moderate group and severe group of patients(F=21.944,F=16.391,F=5.872,F=30.240,F=3.984,F=3.863,F=3.398,F=1.214,P<0.05),respectively.BMI,ALT,TG and FBG appeared positive correlation with LFF and PFF of NAFLD patients(r=0.31,r=0.52,r=0.33,r=0.35,r=0.30,r=0.36,r=0.27,r=0.29,P<0.05),and HDL-c appeared negative correlation with them(r=-0.16,r=-0.3,P<0.05),respectively.Multivariate Logistic regression analysis showed that HDL-c was an independent protective factor of the severity of NAFLD(OR=0.004,P<0.05),and LFF,PFF,BMI,ALT,TG,LDL were independent risk factors of the severity of NAFLD(OR=2.252,OR=1.988,OR=1.404,OR=1.196,OR=1.025,OR=5.150,P<0.05),respectively.Conclusion:LFF and PFF are closely related to the severity of NAFLD and the indicators of liver function,and the increases of LFF and PFF are independent risk factors of the aggravation of NAFLD.The MR quantitative analyses of LFF and PFF values have a certain guiding significance in clinical monitoring for NAFLD severity and liver function.