Objective: To explore the correlation between diabetic nephropathy (DN) and cognitive impairment through examining the cognitive function and the metabolism of the cerebrum in Type 2 diabetes mellitus patients at different stages of renal function.
Methods: Eighty six patients with Type 2 diabetes mellitus (T2DM) were enrolled for this study. According to the urinary albumin excretion rate (UAER), the patients were divided into a T2DM without DN group (DM group, n=33), an early DN group (DN-III group, n=26) and a clinical stage group (DN-IV group, n=27). Thirty healthy adults were selected as a control group (NC group). Biochemical indexes and UAER were measured, and glomerular filtration rate (GFR) was detected by single-photon emission computed tomography (SPECT). The cognitive function was measured by Montreal Cognitive Assessment (MoCA, Beijing version) and mini-mental state examination (MMSE). The peak areas of N-acetylasparte (NAA), creatine (Cr), choline-containing compounds (Cho) were detected by proton magnetic resonance spectroscopy (1H-MRS).
Results: 1) There was no statistical difference in MMSE scores between the DM group and the control group. The scores of MoCA in the DN-III group or in the DN-IV group were significant less than that in the NC group (F=3.66, P<0.05); 2) There was significant difference in left N-acetylaspartate (LNAA), left choline (LCho) among the diabetes groups. Compared with the DM group, the level of LNAA was decreased significantly (t=3.826, P<0.05) while the LCho was increased significantly (t=4.373, P<0.05) in the DN groups, with statistic difference between the 2 groups (t=3.693, P<0.05); 3) The MoCA scores of T2DM patients were negatively correlated with UAER (r=-0.285, P<0.05), while positively correlated with GFR (r=0.379, P<0.05); 4) Logistic regression analysis indicated that UAER and GFR were the major risky factors for diabetic cognitive impairment.
Conclusion: Diabetic cognitive impairment is closely correlated with the nephropathy in patients with Type 2 diabetes. With the decline in glomerular filtration function, the cognitive disorder tends to be aggravated. The hippocampal brain metabolism may have some changes in left side of Cho/Cr in patients with diabetic nephropathy.
目的：通过检测不同时期的2型糖尿病肾病(diabetic nephropathy，DN)患者认知功能及脑代谢的变化，探讨2型糖尿病认知功能障碍与肾微血管病变的相关性。方法：86例2型糖尿病患者根据尿白蛋白排泄率(urinary albumin excretion rate，UAER)水平分为糖尿病无肾病组(DM组，n=33)、早期DN组(DN-III组，n=26)、临床期DN组(DN-IV组，n=27)，另选健康受试者为正常对照组(NC组，n=30)。所有受试者均检测血生物化学指标和UAER，使用单光子发射计算机断层成像术检测肾小球滤过率(glomerular filtration rate，GFR)。用简明精神状态量表(mini-mental state examination，MMSE)和蒙特利尔认知评估量表(Montreal Cognitive Assessment，MoCA)评估认知功能的变化。用氢磁共振质子波谱分析技术检测N-乙酰天冬氨酸(N-acetylasparte，NAA)峰、含胆碱复合物(choline-containing compounds，Cho)峰、肌酸复合物(creatine，Cr)峰的共振峰波谱峰值及波峰曲线下面积。结果：1)4组受试者MMSE评分差异均无统计学意义(均P>0.05)。DN-III组及DN-IV组患者MoCA总分较对照组均显著降低(均P<0.05)；2)DN组左侧NAA值较DM组显著下降(t=3.826，P<0.05)，而左侧Cho水平明显增高(t=4.373，P<0.05)；两组患者中左侧Cho/Cr差异有统计学意义(t=3.693，P<0.05)；3)Pearson相关分析显示：2型糖尿病患者MoCA评分与UAER呈负相关(r=−0.285，P<0.05)，与GFR呈正相关(r=0.379，P<0.05)；4)Logistic回归分析显示UAER增高与GFR下降是糖尿病认知功能障碍的独立危险因素。结论：2型糖尿病患者认知功能障碍与肾微血管病变存在相关性，且随着肾损害程度的加重，认知功能障碍呈逐渐加重的趋势。DN患者海马存在代谢物质的改变，表现为左侧海马Cho/Cr增高。.