Albuminuria within the normal range and ultrasound‐assessed atherosclerosis in the AIR study: a 9‐year follow‐up of 58‐year‐old clinically healthy men

Background:Microalbuminuria, traditionally defined as 30–300 mg urinary albumin/24 h, predicts renal impairment and cardiovascular disease. Studies suggest that also a far lower urinary albumin excretion (UAE) can predict clinical outcome. Intima media thickness (IMT) is an established estimate of atherosclerosis. In this study, we investigated the predictive value of UAE within the normal rate (UAE–n) for the progression of IMT in the carotid and femoral arteries. Methods: We included 325 clinically healthy men with normoalbuminuria. Anthropometrics, urine and blood samples were taken and IMT in the carotid and femoral arteries were assessed by B–mode ultrasound at baseline and after 3 and 9 years. The annual progression rate of IMT (r–IMT) was calculated. Results: UAE–n correlated with carotid IMT at baseline and after 3 and 9 years, but not with r–IMT. In a regression analysis, only HDL and baseline IMT remained as statistically significant co–variates to mean IMT at 9 years. IMT in the femoral artery and r–IMT at any time–point did not correlate to baseline UAE. Conclusion: UAE–n was associated with carotid IMT after 3 and 9 years but not r–IMT or with femoral artery IMT. Carotid IMT after 9 years' follow–up was independently related to baseline IMT and HDL cholesterol. In this cohort of 58–year–old men, our interpretation is that UAE–n is not associated with the increase in carotid and femoral artery IMT observed after 9 years.     

微白蛋白尿与危重患者预后

微白蛋白尿被认为是反映全身毛细血管渗透性增加的一个重要指标.目前,已经发现许多常见的内科疾病如:糖尿病、肾脏疾病和心血管疾病,都会出现微白蛋白尿,且有文献报道微白蛋白尿与危重患者的预后相关.本文就微白蛋白尿与危重患者预后的关系、预测危重患者疾病严重程度的价值进行简要综述.     

Longitudinal study of urinary albumin excretion in young diabetic patients--Wessex Diabetic Nephropathy Project.

AIMS: This study was established to follow changes in albumin/creatinine ratio (ACR) and to determine the prevalence and degree of progression of microalbuminuria (MA) or of clinical proteinuria (CP) in children with Type 1 diabetes. The study has investigated subjects for up to 12 years in establishing the correlation between MA and gender, age, duration of diabetes and glycated haemoglobin (HbA1c). The study has defined clinical cut-offs for MA in daytime clinic urine samples in young diabetic subjects. METHODS: Three hundred and sixty-one patients were involved in the study, with 221 (61.2%) having over six sets of data. Urine samples were collected at routine annual clinic visits and analysed without prior freezing for ACR. Blood samples were taken for HbA1c measurement. Data including sex, age and duration of diabetes were recorded. RESULTS: A random clinic ACR of < 4.5 mg/mmol (males) and 5.2 mg/mmol (females) creatinine was used as the 'clinical cut-off' to define the presence of MA. The presence of MA was independent of HbA1c and duration of diabetes but appeared be associated with the adolescent years (> 10 years). There was little evidence of progression from normoalbuminuria to MA, or from MA to CP. Of patients aged 10-18 years, 30.9% of males and 40.4% of females had one or more episodes of MA. CONCLUSIONS: Persistent MA and random episodes of MA or CP may be associated with the adolescent years but not with duration of diabetes. Further study will reveal if the substantial increases in ACR sometimes seen during adolescence are predictive of diabetic nephropathy. Clinical cut-offs of < 4.5 and < 5.2 mg/mmol creatinine for males and females, respectively, are suggested for the interpretation of changes in ACR in random urine samples in young people with Type 1 diabetes.     

Predisposition to nephropathy in Polynesians is associated with family history of renal disease, not diabetes mellitus.

AIMS: Familial clustering of diabetes and nephropathy suggests that either common environmental or inherited mechanisms are important in developing diabetic nephropathy. If an inherited mechanism is important, the albumin excretion rate might be increased in those at future risk. This study aimed to determine whether people with a family history of diabetes or people with a family history of renal disease were most at risk. METHODS: In a two-by-two factorial study of urinary albumin in non-diabetic Polynesians, 90 people with a first degree relative (FDR) with end-stage renal failure (ESRF) and diabetes (group 1) were compared with 90 people with a FDR with non-diabetic ESRF (group 2), with 90 people with a FDR with diabetes but no known nephropathy (group 3) and 90 people with no known relatives with either diabetes or nephropathy (group 4). Groups were matched for ethnicity and age. RESULTS: Subjects with a family history of ESRF (groups 1 and 2) had an increased mean albumin-creatinine ratio (1.25 vs. 1.00 mg/mmol, P = 0.01), but in subjects with a family history of diabetes (groups 1 and 3), the mean ratios were not significantly different from those without a family history of diabetes (1.06 vs. 1.17 mg/mmol; P = 0.2). In those with a family history of nephropathy, fasting blood glucose and systolic blood pressure were increased, while fasting insulin and 2 h insulin concentrations were lower. A family history of diabetes was associated with an increased fasting blood glucose and 2-h blood glucose. By multiple linear regression, the mean systolic blood pressure (P = 0.02), the 2-h glucose concentration (P = 0.05), a family history of renal failure (P = 0.04), female sex (P = 0.0001) and the total cholesterol (P = 0.01) were each independently associated with microalbuminuria, while a family history of diabetes was not (P = 0.09). CONCLUSIONS: These data suggest that among Polynesians there is no specific inherited tendency to diabetic nephropathy per se. The risk of nephropathy does not appear to be associated with the degree of familial risk of diabetes itself. Rather, the risk of diabetic nephropathy may be the result of a familial risk of nephropathy from any cause and is associated with diabetes through relative hypoinsulinaemia and hyperglycaemia.     

The impact of Type 2 diabetes and microalbuminuria on future cardiovascular events in patients with clinically manifest vascular disease from the Second Manifestations of ARTerial disease (SMART) study

Aims Type 2 diabetes mellitus and microalbuminuria are important risk factors for cardiovascular disease (CVD). Whether these two complications are important and independent risk factors for future CVD events in a high‐risk population with clinically manifest vascular disease is unknown. The objectives of this study were to examine the impact of Type 2 diabetes and microalbuminuria on future CVD events. Methods Patients with clinically manifest vascular disease (coronary, cerebral and peripheral vascular disease) from the Second Manifestation of Arterial disease study were followed up for 4 years. Data obtained from 1996–2006 were analysed. At baseline, there were 804 patients with Type 2 diabetes mellitus (mean age 60 years) and 2983 patients without. Incident CVD (n = 458) was defined as hospital‐verified myocardial infarction, stroke, vascular death and the composite of these vascular events. Results Both Type 2 diabetes [hazard ratio (HR) 1.42, 95% confidence interval (CI) 1.16, 1.75] and microalbuminuria (HR 1.86, 95% CI 1.49, 2.33) increased the risk of new cardiovascular events in univariate analyses. From multivariable models, presence of diabetes remained significantly and independently related to incident CVD (HR 1.42, 95% CI 1.11, 1.80). Presence of microalbuminuria also remained significantly independently related to incident CVD (HR 1.38, 95% CI 1.07, 1.77). In diabetes‐stratified analyses, the effect of microalbuminuria on CVD risk was observed only in patients with diabetes. In microalbuminuria‐stratified analyses, the significant and independent effect of diabetes on CVD risk was shown only in the non‐microalbuminuric group. Conclusions In this high‐risk population, both microalbuminuria and Type 2 diabetes are important and independent risk factors for future CVD.     

Kidney function and cardiovascular risk factors in non-insulin-dependent diabetics (NIDDM) with microalbuminuria

Microalbuminuria in non-insulin-dependent diabetes (NIDDM) is a strong predictor of increased mortality. The major causes of death are cardiovascular, whereas end-stage renal failure is of low frequency. To define kidney function and the presence of some assumed cardiovascular risk factors, we compared a group of 19 microalbuminuric NIDDM patients (M), of mean age (+/- SD) 65 +/- 4 years, and known duration of diabetes 8 +/- 7 years, with 19 randomly selected matched normoalbuminuric patients (N). Seven microalbuminuric patients (P) were also studied. Glomerular filtration rate (GFR) did not differ between N and M, whereas kidney volume was increased in M (260.3 +/- 54.1 ml 1.73 m-2) compared to N (220.4 +/- 44.8 ml 1.73 m-2; P = 0.018). The frequency of cardiac disease increased with increasing albuminuria. Glycaemic control did not differ between the groups, but fasting plasma C-peptide levels increased from 2.8 +/- 1.1 micrograms l-1 in N, to 3.7 +/- 1.7 micrograms l-1 in M (P = 0.08), and to 4.2 +/- 1.9 micrograms l-1 (P = 0.03) in P. The lipoprotein profile showed no significant differences, although the LDLcholesterol/HDLcholesterol (LDL-C/HDL-C) ratio tended to rise. A significant correlation was found between C-peptide and LDL-C/HDL-C (r = 0.5; P less than 10(-3]. In conclusion, GFR was not increased, and did not differ between N and M, whereas kidney volume was enhanced in M. Several assumed cardiovascular risk factors showed values of M intermediate between those of N and P.     

联合检测血同型半胱氨酸、糖化血红蛋白与尿微量白蛋白、β_2-微球蛋白在2型糖尿病早期肾损害诊断的临床价值

目的探讨血同型半胱氨酸(Hcy)、糖化血红蛋白(HbA1c)、尿微量白蛋白(尿mALB)、尿β2-微球蛋白(尿β2-MG)等指标对2型糖尿病(T2DM)早期肾损害的诊断价值。方法回顾性分析我院196例不同病程2型糖尿病患者及同期158例健康体检人员的HbA1c、血Hcy、尿mALB、尿β2-MG检测结果,并进行统计学处理。结果在T2DM患者中Hcy阳性率(男:47.6%,女:50.5%)最高,且存在性别差异;尿β2-MG阳性率(男:25.2%,女:24.7%)最低;这四项指标中,糖尿病组均明显高于对照组,且随着病程的延长,这些指标较糖尿病初期增高明显。结论定期联合检查T2DM患者HbA1c、血Hcy、尿mALB、尿β2-MG能及时了解糖尿病早期是否存在肾损害及其部位(肾小球、近端肾小管),以便临床医生及时采取有效措施,防止或延缓糖尿病肾病的发生。