绝经后新诊断2型糖尿病腰椎骨髓脂肪成分的MRS测定

摘要

目的 探讨磁共振波谱成像(MRS)用于定量绝经后新诊断2型糖尿病(T2DM)病人骨髓脂肪成分的变化,并分析其与糖化血红蛋白(HbA1C)的相关性.方法 收集25例绝经后新诊断T2DM女性病人,年龄(57.4±4.5)岁,以25例健康女性作为对照者,年龄(56.6±4.0)岁.两组均行腰3椎体1H-MRS扫描,计算骨髓脂肪含量(FC)及不饱和脂肪指数(UFI).测定被检者空腹血糖及HbA1C.采用独立样本t检验比较组间年龄、体质量指数(BMI)、血糖、HbA1C、FC及UFI差异,采用Pearson相关分析两组的FC、UFI与血糖及HbA1C的相关性.结果T2DM组骨髓FC值(63.2%±7.4%)与正常对照组(60.9%±6.9%)差异无统计学意义,但T2DM组骨髓UFI(6.1%±0.8%)较正常对照组(7.6%±0.9%)降低(t=-3.775,P<0.001).T2DM组HbA1C>7.0%者的骨髓FC(66.0%±6.3%)高于HbA1C≤7.0%者(57.6%±6.5%)(t=2.893,P<0.001).T2DM组骨髓FC与HbA1C呈高度正相关(r=0.801,P<0.001),而骨髓UFI与HbA1C水平呈负相关(r=-0.746,P<0.001),但FC(r=0.226,P=0.206)和UFI(r=-0.184,P=0.589)与血糖无相关性.结论 T2DM病人腰椎骨髓FC可无明显变化,但UFI明显降低.T2DM骨髓脂肪成分与HbA1C密切相关, MRS测定骨髓脂肪组分可看作血糖控制程度的标志.%Objective To detect the vertebral marrow fat compositions in postmenopausal women with newly diag-nosed type 2 diabetes mellitus (T2DM) assessed by MRS, and to analyze the relationships between marrow fat compositions and hemoglobin A1C (HbA1C). Methods This study included 25 (mean age, 57.4 ±4.5 years) newly diagnosed T2DM patients and 25 age-and BMI-matched healthy controls (mean age, 56.6±4.0 years) who underwent 1H-MRS scans at the L3 vertebral body. Total marrow fat content (FC) and unsaturated fat index (UFI) were measured. HbA1C and fasting plasma glucose were measured. Differences in age, body mass index (BMI), glucose, HbA1C, FC, and UFI between groups were com-pared with t-test. Associations of FC and UFI with glucose and HbA1C were tested using Pearson correlation analysis. Results There was no significant difference in FC between the T2DM women and healthy controls (63.2%±7.4%versus 60.9%±6.9%), but UFI was significantly lower in the T2DM group (6.1%±0.8%versus 7.6%±0.9%;t=-3.775, P<0.001). FC was higher in T2DM patients with HbA1C>7.0 than those with HbA1C≤7.0% (66.0%±6.3%versus 57.6%±6.5%;t=2.893, P<0.001). HbA1C value was positively correlated with FC value (r=0.801, P<0.001) and inversely associated with UFI(r=-0.746, P<0.001) in the T2DM group. No association of blood glucose with FC (r=0.226, P=0.206) and UFI(r=-0.184, P=0.589) were observed. Conclusions Vertebral marrow UFI is significantly decreased in postmenopausal women with T2DM. Marrow fat content is strongly associated with HbA1C in T2DM. MRS of spinal marrow fat may serve as a novel tool for moni-toring blood glucose control.