Factors associated with progression to macroalbuminuria in microalbuminuric Type 1 diabetic patients: the EURODIAB Prospective Complications Study

Aims/hypothesis Type 1 diabetic patients who develop microalbuminuria are clearly disadvantaged in terms of their risk of morbidity and mortality from renal and cardiovascular diseases. It is therefore important to identify potential factors that can predict progression to macroalbuminuria.Methods This is a 7-year follow-up study of 352 microalbuminuric Type 1 diabetic patients from 31 European centres. Risk factors at baseline were compared in patients who progressed to macroalbuminuria and in patients who remained microalbuminuric or reverted to normoalbuminuria. Risk factors and albumin excretion rate (AER) were measured centrally.Results Over 7.3 years, 13.9% of the microalbuminuric patients progressed to macroalbuminuria, 35.5% remained microalbuminuric and 50.6% reverted to normoalbuminuria. Independent baseline risk factors for progression to macroalbuminuria were HbA₁c (7.9% vs 6.8%, p=0.004), AER (64.4 vs 44.9 µg/min, p=0.0001) and—after adjusting for diabetes duration, HbA₁c and AER—body weight (72 vs 67 kg, p=0.05). Independent factors associated with regression to normoalbuminuria were diabetes duration (15 vs 18 years, p=0.004), AER (37.2 vs 44.9 µg/min, p=0.0001) and—after adjusting for diabetes duration, HbA₁c and AER—waist-to-hip ratio (0.83 vs 0.86, p=0.05) and incidence of peripheral neuropathy at baseline (24% vs 38%, p=0.001). Blood pressure and smoking did not emerge as risk factors at baseline for the outcome of microalbuminuria.Conclusions/interpretation A significant fraction of microalbuminuric Type 1 diabetic patients will progress to overt proteinuria. Patients with higher AER values, sub-optimal metabolic control, excess body fat and peripheral neuropathy may carry a particularly high risk of clinical nephropathy requiring aggressive therapeutic intervention.Abbreviations AER albumin excretion rate - CVD cardiovascular disease - Gamma GT gamma-glutamyltransferase - OR odds ratio - PCS Prospective Complications Study - RR relative risk - SERR standardised estimates of relative risk - SREs standardised regression effects - vWF von Willebrand Factor     

A Prospective Study of Clinical and Metabolic Associates of Proteinuria in Patients with Type 2 Diabetes Mellitus

Urinary protein excretion rate and clinical and metabolic associates were investigated in a group of 108 patients with Type 2 diabetes mellitus at the time of diagnosis and after 5 years, and also 121 control subjects. The presence of coronary heart disease, neuropathy and retinopathy, cardiovascular risk factors and 24-h urinary excretion rate of albumin, beta-2-microglobulin, and IgG were examined. At the 5-year examination, urinary excretion rate of albumin was higher in diabetic patients than in control subjects (39 ± 75 vs 16 ± 28 mg 24 h^?1 for men, p < 0.05; 38 ± 57 vs 22 ± 42 mg 24^?1 h for women, p < 0.01). Furthermore, increased beta-2-microglobulin excretion rate, a marker of tubular impairment, was observed in diabetic men as compared to control men (0.17 ± 0.15 vs 0.14 ± 0.21 mg 24 h^?1, p < 0.05). Diabetic patients with increased albumin excretion rate (> 30 mg 24 h^?1) showed poorer metabolic control than those with normal albumin excretion rate, but no significant differences in body mass index or in the frequencies of smoking, hypertension, coronary heart disease or retinopathy and neuropathy were observed between the groups. Baseline hyperinsulinaemia was closely associated with increasing albuminuria at the 5-year examination.     

Orosomucoid in urine predicts cardiovascular and over-all mortality in patients with Type II diabetes

Aims/hypothesis: Urinary orosomucoid excretion rate is increased in a substantial proportion of patients with Type II (non-insulin-dependent) diabetes mellitus and normal urinary albumin excretion rate. The aim of this study was to determine whether increased urinary orosomucoid excretion rate is predictive of increased mortality in patients with Type II diabetes. Methods: In a cohort study including 430 patients with Type II diabetes, baseline urinary samples were analysed for orosomucoid and albumin. Mean follow-up was 2.4 years. Results: We found that 188 (44 %) patients had normal and 242 (56 %) patients had increased urinary orosomucoid excretion rates. During the study period 41 patients died; out of these 23 patients died of cardiovascular diseases. Odds ratio for all-cause mortality was 2.50 (95 % CI 1.00–6.22) and odds ratio for cardiovascular mortality was 9.81 (1.31–73.6) having increased urinary orosomucoid excretion rate at baseline (odds ratios adjusted for age, sex, duration of diabetes, cardiovascular diseases, weight, medication, HbA_{1 c}, plasma creatinine and urinary albumin excretion rate). Urinary albumin excretion rate was an independent predictor of all-cause mortality when urinary orosomucoid excretion rate was not included in the analysis. Subgroup analysis revealed that 39 % of the patients with normal urinary albumin excretion rate (n = 251) had increased urinary orosomucoid excretion rates and that these patients had a higher cardiovascular mortality (p = 0.007) than patients with normal urinary albumin excretion rate and normal urinary orosomucoid excretion rates. Conclusion/interpretation: We found that urinary orosomucoid excretion rate predicted all-cause and cardiovascular mortality in patients with Type II diabetes independently from other risk factors. [Diabetologia (2002) 45: 115–120] Received: 24 July 2001 and in revised form: 17 September 2001     

Haemostatic Measures in Type 2 Diabetic Patients with Microalbuminuria

The major cause of disability and early mortality in Type 2 diabetes is cardiovascular disease. An enhanced urinary albumin excretion is strongly predictive of increased mortality, but the causal relationship behind this association is unclear. Abnormalities in the haemostatic system may be involved in the vascular pathology. We therefore studied the level of von Willebrand factor (vWf:Ag), factor VIII (VIII:Ag), fibrinogen, and fibronectin in male diabetic patients 50–70 years of age, with normal albumin excretion (n = 14), microalbuminuria (n = 14), and frank albuminuria (n = 7). Fourteen healthy age-matched males served as a reference group. There were no significant differences between normo-and micro-albuminuric patients but vWf:Ag (p < 0.01), VIII:Ag (p < 0.01), and fibrinogen (p < 0.05) were increased in those with frank albuminuria. Urinary albumin excretion rate was significantly correlated to vWf:Ag (r = 0.46, p = 0.005), VIII:Ag (r = 0.45, p = 0.007), and fibrinogen (r = 0.49, p = 0.003). The known duration of diabetes was correlated to vWf and F VIII. The increased level of vWf:Ag in Type 2 diabetes and the significant association to the urinary albumin excretion rate may suggest a linkage between albuminuria and cardiovascular disease. However, the present study demonstrated no increase in haemostatic variables in patients with microalbuminuria as compared with those with normal albumin excretion.     

Plasma concentration of C-reactive protein is increased in Type I diabetic patients without clinical macroangiopathy and correlates with markers of endothelial dysfunction: evidence for chronic inflammation

Summary Moderately increased plasma concentrations of C-reactive protein are associated with an increased risk of cardiovascular disease. C-reactive protein, its relation to a low degree of inflammatory activation and its association with activation of the endothelium have not been systematically investigated in Type I (insulin-dependent) diabetes mellitus. C-reactive protein concentrations were measured in 40 non-smoking patients with Type I diabetes without symptoms of macrovascular disease and in healthy control subjects, and in a second group of Type I diabetic patients (n = 60) with normo- (n = 20), micro- (n = 20) or macroalbuminuria (n = 20). Differences in glycosylation of α₁-acid glycoprotein were assayed by crossed affinity immunoelectrophoresis. Activation of the endothelium was measured with plasma concentrations of endothelial cell markers. The median plasma concentration of C-reactive protein was higher in Type I diabetic patients compared with healthy control subjects [1.20 (0.06–21.64) vs 0.51 (0.04–9.44) mg/l; p < 0.02]. The Type I diabetic subjects had a significantly increased relative amount of fucosylated α₁-acid glycoprotein (79 ± 12 % vs 69 ± 14 % in the healthy control subjects; p < 0.005), indicating a chronic hepatic inflammatory response. In the Type I diabetic group, log(C-reactive protein) correlated significantly with von Willebrand factor (r = 0.439, p < 0.005) and vascular cell adhesion molecule-1 (r = 0.384, p < 0.02), but not with sE-selectin (r = 0.008, p = 0.96). In the second group of Type I diabetic patients, increased urinary albumin excretion was associated with a significant increase of von Willebrand factor (p < 0.0005) and C-reactive protein (p = 0.003), which were strongly correlated (r = 0.53, p < 0.0005). Plasma concentrations of C-reactive protein were higher in Type I diabetic patients without (clinical) macroangiopathy than in control subjects, probably due to a chronic hepatic inflammatory response. The correlation of C-reactive protein with markers of endothelial dysfunction suggests a relation between activation of the endothelium and chronic inflammation. [Diabetologia (1999) 42: 351–357] Received: 4 September 1998 and in final revised form: 24 November 1998     

Current status of Type 2 (non-insulin-dependent) diabetic subjects on dialysis therapy in Japan

Summary According to a national survey of dialysis patients in Japan conducted by the Japanese Society for Dialysis Therapy, there were 1,033 patients on dialysis in the Shiga area which has a population of about 1.2 million. Of these 1,033 dialysis patients 140 were the result of diabetic nephropathy. From four hospitals affiliated to Shiga University of Medical Science the medical records of 90 diabetic subjects on dialysis therapy were reviewed and various clinical parameters were analysed and compared with those of patients with chronic glomerulonephritis. Since only one patient had Type 1 (insulin-dependent) diabetes, the remaining 89 with Type 2 (non-insulin-dependent) diabetes were used for this study. The significantly different variables between patients with Type 2 diabetes and chronic glomerulonephritis were age (60.4 vs 54.6 years,p<0.05), BMI (22.4 vs 20.6 kg/m²,p<0.001), cardiothoracic ratio (56.4 vs 53.3%,p<0.001), mean blood pressure (110 vs 117 mm Hg,p<0.05), serum creatinine (9.0 vs 11.5 mg/dl,p<0.001), serum urea-N (98.2 vs 115.5 mg/dl,p<0.001), serum total protein (6.0 vs 6.5 g/dl,p<0.001) and serum albumin (3.5 vs. 3.9 g/dl,p<0.001). Serum levels of cholesterol and triglyceride were not significantly different between two groups, though the prevalence of electrocardiogram abnormalities, oedema, neuropathy, myocardial infarction and cerebrovascular diseases was significantly higher in the Type 2 diabetic group. These results suggested that Type 2 diabetic patients with end-stage renal disease were older, more malnurished, fluid overloaded and multi-morbid as a result of vasculopathy and neuropathy. However, the analysis of causes of death in Type 2 diabetic patients (n=24) and patients with chronic glomerulonephritis (n=26) failed to provide evidence of higher risk of cardiac death in the Type 2 diabetic group compared to the group with chronic glomerulonephritis (37.5 vs 34.6%, NS). In the Type 2 diabetic patients on dialysis therapy, malnutrition, fluid overload and neuropathy appeared to be significant factors influencing the outcome of the therapy, while in patients with chronic glomerulonephritis, age and vascular morbidities were considered to be major risk factors for the prognosis.     

The metabolic syndrome influences the risk of chronic complications in patients with type II diabetes

Aims/hypothesis: We examined features of the metabolic syndrome to see if they modified the risk of chronic diabetic complications in patients with Type II (non-insulin-dependent) diabetes mellitus. Methods: A total of 85 randomly selected patients with the metabolic syndrome (WHO definition) were compared with 85 Type II diabetic patients matched for age, sex, duration of diabetes, glycaemic control and without the syndrome to assess the microvascular and macrovascular complications. Results: The patients with the metabolic syndrome had a higher prevalence of cardiovascular disease (52 vs 21 %, p < 0.001), microalbuminuria or macroalbuminuria (23 vs 7 %, p = 0.003) and distal neuropathy (16 vs 6 %, p = 0.048) than patients without the syndrome. The patients with the metabolic syndrome had smaller LDL particle size (25.4 ± 1.4 vs 26.4 ± 1.1 nm; p < 0.001), which correlated with the ratio of serum triglycerides to HDL cholesterol (r = –0.64, p < 0.001). In a multiple logistic regression analysis the metabolic syndrome was associated with coronary heart disease (RR 3.84, p < 0.001) and microalbuminuria (RR 3.99, p = 0.01). Small LDL particle size was independently associated with neuropathy (RR 0.58; p = 0.04), whereas a high HbA_{1 c} was related to neuropathy (RR 1.69, p = 0.04), retinopathy (RR 1.53, p = 0.002) and microalbuminuria (RR 1.54, p = 0.01). Conclusion/interpretation: Although chronic hyperglycaemia is the main predictor of microvascular complications in patients with Type II diabetes, this risk is modified by some of the components of the metabolic syndrome. [Diabetologia (2001) 44: 1148–1154] Received: 9 February 2001 and in revised form: 17 May 2001     

Predictors of the development of microalbuminuria in patients with Type 1 diabetes mellitus: a seven-year prospective study

Aims To determine risk factors for the development of persistent microalbuminuria (albumin excretion rate (AER) ≥ 30 μg/min) in Type 1 diabetes mellitus. Methods One hundred and forty-eight initially normotensive Type 1 diabetic patients with normal albumin excretion (< 30 μg/min) were followed prospectively in hospital diabetes outpatient clinics for a median of 7 years. Main outcome measures were: progression to persistent microalbuminuria (albumin excretion rate ≥ 30 μg/min on at least two consecutive occasions); rate of change of albumin excretion rate; development of arterial hypertension (systolic blood pressure > 160 mmHg and/or diastolic blood pressure > 95 mmHg or commencement of antihypertensive therapy). Results In a median follow-up period of 7 years (range 6 months to 8 years), 14 patients progressed to persistent microalbuminuria, a cumulative incidence of 11% (95% confidence interval 6.36–16.94). AER remained persistently < 30 μg/min in 109 subjects and 25 developed intermittent microalbuminuria. In those who developed persistent microalbuminuria, baseline AER (16.2 (13.9–19.1) vs. 5.2 (3.8–9.2) μg/min, P < 0.01), blood pressure (136 (123–148)/80 (74–85) vs. 121 (118–124)/72 (70–73) mmHg, P < 0.05), and HbA₁ (10.2 (9.1–11.4) vs. 9.0 (8.7–9.4)%, P < 0.05) were higher than in those who continued to have persistent normoalbuminuria, retinopathy was more severe and height (1.64 (1.57–1.71) vs. 1.70 (1.69–1.72) m, P < 0.05) less. In multivariate analysis, baseline AER was the strongest predictor of the development of persistent microalbuminuria (P < 0.0001), followed by mean arterial pressure (P = 0.02) and HbA₁ (P = 0.05). Conclusions The level of AER, raised blood pressure and poor glycaemic control are the most important predictors of the development of microalbuminuria in Type 1 diabetes.     

High prevalence of risk factors for cardiovascular disease in parents of IDDM patients with albuminuria

Summary Life expectancy is shorter in the subset of insulin-dependent diabetic (IDDM) patients who are susceptible to kidney disease. Familial factors may be important. In this study the prevalence of cardiovascular disease mortality and morbidity and of risk factors for cardiovascular disease was compared in the parents of 31 IDDM patients with elevated albumin excretion rate (AER > 45 μg/min; group A) with that of parents of 31 insulin-dependent diabetic patients with normoalbuminuria (AER < 20 μg/min; group B). The two diabetic patient groups were matched for age and duration of disease. Information on deceased parents was obtained from death certificates and clinical records and morbidity for cardiovascular disease was ascertained using the World Health Organization questionnaire and Minnesota coded ECG. Hyperlipidaemia was defined as serum cholesterol higher than 6 mmol/l and/or plasma triglycerides higher than 2.3 mmol/l and/or lipid lowering therapy; arterial hypertension as systolic blood pressure higher than 140 mmHg and/or diastolic blood pressure higher than 90 mmHg and/or antihypertensive treatment. The percentage of dead parents was similar in the two groups (26 vs 20 % for parents of group A vs group B, respectively), but the parents of the diabetic patients with elevated AER had died at a younger age (58 ± 10 vs 70 ± 14 years; p < 0.05). Parents of diabetic patients with nephropathy had a more than three times greater frequency of combined mortality and morbidity for cardiovascular disease than that of the parents of diabetic patients without nephropathy (26 vs 8 %; odds ratio 3.96, 95 % CI 1.3 to 12.2; p < 0.02). Living parents of group A had a higher prevalence of arterial hypertension (42 vs 14 % p < 0.01) and hyperlipidaemia (49 vs 26 % p < 0.05) as well as higher levels of lipoprotein (a) [median (range) 27.2 (1–107) vs 15.6 (0.2–98) mg/dl; p < 0.05]. They also had reduced insulin sensitivity [insulin tolerance test: median (range) K_itt index: 3.7 (0.7–6.2) vs 4.8 (0.7–6.7)% per min; p < 0.05]. In the families of IDDM patients with elevated AER there was a higher frequency of risk factors for cardiovascular disease as well as a predisposition to cardiovascular disease events. This may help explain, in part, the high prevalence of cardiovascular disease mortality and morbidity in those IDDM patients who develop nephropathy. [Diabetologia (1997) 40: 1191–1196] Received: 4 March 1997 and in revised form: 9 May 1997     

The Relationship Between Plasminogen Activator Inhibitor-1 and Insulin Resistance in Newly Diagnosed Type 2 Diabetes Mellitus

It is not clear whether elevated levels of the fibrinolytic inhibitor, plasminogen activator inhibitor-1 (PAI-1) in Type 2 diabetes mellitus are the result of obesity or coexistent atherosclerosis. Therefore the relationship between PAI-1 and insulin resistance, determined by the homeostasis model assessment (HOMA) was investigated in a group of 26 insulin-resistant, normotensive newly diagnosed Type 2 diabetic patients with a low probability of atherosclerosis. Compared with a normal control group, closely matched for body mass index (BMI), fibrinolytic activity was depressed in the diabetic patients due to elevated levels of the inhibitor PAI-1, 17.6 (11.1–28) vs 8.4 (4.9–14.1) IU ml^?1, p < 0.001. PAI-1 was related to BMI, r = 0.59, p < 0.001 plasma insulin, r=0.66, p < 0.001; insulin resistance, r = 0.54, p< 0.005 and urinary albumin excretion, r=0.48, p < 0.01, but not HbA_1c or fasting glucose. PAI-1 was not related to blood pressure or plasma triglyceride levels. This study suggests that at the time of diagnosis of Type 2 diabetes mellitus, elevated PAI-1 levels are already linked to other risk factors for vascular disease including hyperinsulinaemia, insulin resistance, and urinary albumin excretion, and this is not the result of obesity or coexistent atherosclerosis.     

Prothrombotic and Antithrombotic Factors are Elevated in Patients with Type 1 Diabetes Complicated by Microalbuminuria

Increased urinary albumin loss in patients with Type 1 diabetes is associated with accelerated atherosclerosis. Prothrombotic factors known to be associated with cerebrovascular and coronary artery disease in the general population, and antithrombotic factors, were studied in 52 patients with Type 1 diabetes and varying urinary albumin loss and 24 non-diabetic control subjects. Fibrinogen increased from 2.5 g I_-1 (95 % confidence interval 2.3–2.8) in control subjects and 2.8 g I_-1 (2.6–3.0) in diabetic patients without microalbuminuria to 3.1 g I_-1 (2.7–3.5) with microalbuminuria (p < 0.005 vs control; p < 0.001 vs without microalbuminuria). Factor VIIc increased from 81 % (75–86 % in non-diabetic control subjects and 84 % (78–90 %) in diabetic patients without microalbuminuria to 103 % (89–117 %) with microalbuminuria (p < 0.005 vs control; p < 0.05 vs without microalbuminuria) and 118% (86–150%) with albuminuria (p < 0.005 vs control and p < 0.001 vs without microalbuminuria). Levels of the antithrombotic factors protein C, protein S, and antithrombin III also rose in the diabetic patients with evidence of renal damage. Elevation of prothrombotic factors has been associated with increased risk of microvascular disease, whereas elevation of antithrombotic factors has no known protective effect. Therefore, this pattern of alteration of haemostatic factors in diabetic renal disease may contribute to the increased risk of vascular disease associated with both microalbuminuria and albuminuria.     

Genetic influence of the R/Q353 genotype on factor VII activity is overwhelmed by environmental factors in Chinese patients with Type II (non-insulin-dependent) diabetes mellitus

Summary We studied the effects of genetic and environmental influences on factor VII coagulant activity (VIIc) in Chinese diabetic patients (263 with Type II [non-insulin-dependent] diabetes mellitus, 78 with Type I [insulin-dependent] diabetes mellitus) and 143 normal control subjects. VIIc was measured by a one-stage biological assay. The R/Q353 or Msp1 polymorphism at codon 353 of the factor VII gene was detected after Msp1 digestion of polymerase chain reaction-amplified genomic DNA. In both diabetic and control subjects the allele frequencies of the R (M1) and Q (M2) alleles were 0.96 and 0.04; the corresponding reported frequencies in Caucasians being 0.90 and 0.10: VIIc were 21 % lower in Chinese control subjects and Type I diabetic patients with R/Q, compared with R/R subjects (p < 0.001 and p < 0.05). The corresponding difference was 4 % for Type II diabetc patients (p = NS). Type II diabetic patients had higher mean VIIc levels than control subjects and Type I diabetic patients (p < 0.01); they were also older, and had higher serum creatinine and triglyceride (all p < 0.01). They also had higher VIIc levels than an age-matched older control group (p < 0.01; n = 182) in whom the genotype effect was clearly seen. On stepwise linear regression analysis, the significant independent determinants of VIIc were serum triglyceride (contributing 20 % and 25 % to variance in control subjects and diabetic patients), the R/Q353 genotype (contributing to 12 % of the variance in control subjects but only 1 % in diabetic patients), age and total cholesterol in all subjects, and in the diabetic patients female sex, urinary albumin excretion rate and serum creatinine. VIIc was higher in diabetic patients with macroangiopathy and retinopathy (both p < 0.0001). We conclude that compared with Caucasians, the Q allele frequency is significantly lower in these Chinese subjects. Plasma VIIc is determined by both genetic and environmental influences such that in Chinese Type II diabetic patients, the effect of environmental factors predominates, almost negating the influence of the R/Q353 genotype. High VIIc may contribute to the increased cardiovascular risk in Type II diabetic patients. [Diabetologia (1998) 41: 760–766] Received: 24 October 1997 and in final revised form: 28 January 1998     

Post-exercise Albuminuria Does Not Predict Microalbuminuria in Type 1 Diabetic Pantients

To investigate whether post-exercise urinary albumin excretion in Type 1 diabetic children and adolescents may prospectively predict the development of microalbuminuria, we have assessed post-exercise urinary albumin excretion before and after 6.2 ± 1.7 years of follow-up in 66 diabetic children and adolescents. Post-exercise urinary albumin excretion rose significantly above the pre-exercise values in diabetic patients by 2.7 (-3.8 to 84.2) μ min^?1 (p < 0.001) and in a group of 9 healthy individuals by 3.9 (-0.7 to 13.7) μg min^?1 (p < 0.02) without significant differences betbeen groups. Post-exercise albuminuria was greater in postpubertal than prepubertal 9.8 vs 4.3 μg min^?1 (p < 0.03) and pubertal 9.8 vs 6.0 μg min^?1 (p < 0.02) patients; post-exercise changes in urinary albumin excretion were also positively related to glycated haemoglobin (r = 0.293; p < 0.05). Eight out of 66 patients developed microalbuminuria at follow-up. Urinary albumin excretion at follow-up was comparable between patients with normal and abnormal post-exercise urinary albumin excretion; moreover post-exercise urinary albumin excretion was within the normal range in 5 out of 8 patients with microalbuminuria at follow-up. In conclusion post-exercise albuminuria does not seem to be a useful predictor of the onset of microalbuminuria in Type 1 diabetic children and adolescents.     

Plasma N-terminal pro-B-type natriuretic peptide and mortality in type 2 diabetes

Aims/hypothesis Raised N-terminal pro-B-type natriuretic peptide (NT-proBNP) is associated with a poor cardiac outcome in non-diabetic populations. Elevated NT-proBNP predicts excess morbidity and mortality in diabetic patients with an elevated urinary albumin excretion rate. This study investigated the prognostic value of NT-proBNP in a cohort of type 2 diabetic patients. Subjects, materials and methods In a prospective observational follow-up study, 315 type 2 diabetic patients with normoalbuminuria (n=188), microalbuminuria (n=80) and macroalbuminuria (n=47) at baseline were followed for a median (range) of 15.5 (0.2–17.0) years. Plasma NT-proBNP concentrations were determined by immunoassay at baseline. Endpoints were overall and cardiovascular mortality. Results Of the patients, 162 died (51%), 119 of them (74%) due to cardiovascular causes. All-cause mortality was increased in patients with NT-proBNP in the second and third tertiles (hazard ratios [95% CI] compared with the first tertile, 1.70 [1.08–2.67] and 5.19 [3.43–7.88], p<0.001). These associations persisted after adjustment for urinary albumin excretion rate, glomerular filtration rate and conventional cardiovascular risk factors (covariate adjusted hazard ratios 1.46 [0.91–2.33] and 2.54 [1.56–4.14], p<0.001). This increased mortality was attributable to more cardiovascular deaths in the second and third NT-proBNP tertile (unadjusted hazard ratios 1.63 [0.96–2.77] and 4.88 [3.01–7.91], p<0.001; covariate adjusted 1.37 [0.79–2.37] and 2.26 [1.27–4.02], p=0.01). When patients with normo-, micro- and macroalbuminuria were analysed separately, NT-proBNP levels above the median (62 ng/l) were consistently associated with increased overall and cardiovascular mortality in all three groups (p<0.001). Conclusions/interpretation In patients with type 2 diabetes, elevated circulating NT-proBNP is a strong predictor of the excess overall and cardiovascular mortality, this predictor status being independent of urinary albumin excretion rate and conventional cardiovascular risk factors.     

Alterations in serum lipids and apolipoproteins in male Type 1 (insulin-dependent) diabetic patients with microalbuminuria

Summary The relationships between serum lipid, apolipoprotein levels and urinary albumin excretion were investigated in 20 male Type 1 (insulin-dependent) diabetic patients with microalbuminuria (overnight urinary albumin excretion between 10 and 200 g/min), in 18 male Type 1 diabetic patients without microalbuminuria and in 18 male control subjects. In the microalbuminuric patients low density lipoprotein cholesterol was higher than in the control subjects (p<0.05); the high density lipoprotein/low density lipoprotein cholesterol ratio was lower than in the normoalbuminuric diabetic patients (p<0.05), and in the control subjects (p<0.01); apolipoprotein B was higher than in the normoalbuminuric patients (p<0.05); the apolipoprotein A₁/B ratio was lower than in the normoalbuminuric diabetic patients (p<0.05). Serum triglyceride was higher in the microalbuminuric diabetic patients and in the control subjects than in the normoalbuminuric diabetic patients (p<0.05, for both), but was not different between the microalbuminuric diabetic patients and the control subjects. No significant differences between the 3 groups were present with respect to serum cholesterol, high density lipoprotein cholesterol and apolipoprotein A₁. In the 2 combined Type 1 diabetic groups there were significant correlations between urinary albumin excretion and the high density lipoprotein/low density lipoprotein cholesterol ratio (R -0.40, p<0.02), apolipoprotein B (R0.35, p<0.05) and the apolipoprotein A₁/B ratio (R -0.44, p<0.01). These results indicate microalbuminuria related differences in lipid and apolipoprotein levels in male Type 1 diabetic patients, which may contribute to an increased risk of cardiovascular disease.     

Thrombomodulin Levels in Insulin-dependent Diabetic Patients with Microalbuminuria

Thrombomodulin (TM) plays an important role in the regulation of blood coagulation at the endothelial surface. TM is also present in plasma, where an increase of its level seems to reflect endothelial damage. Since microalbuminuria is associated with an increased atherothrombotic risk and is considered an expression of widespread vascular damage, we evaluated plasma thrombomodulin levels, blood pressure, and plasma lipid values in Type 1 diabetic patients with micro- and normoalbuminuria. Thrombomodulin was measured in 12 microalbuminuric (albumin excretion rate 20–200 μg min^?1 in 2 of 3 overnight urine collections) and in 12 normoalbuminuric (albumin excretion rate < 20 μg min^?1) Type 1 diabetic patients matched for age, sex, body mass index, smoking habits, diabetes duration, and glycated haemoglobin. Mean thrombomodulin was significantly higher in micro- than in normalbuminuric group (59.34 ± 3.58 vs 43.56 ± 3.52 ng ml^?1 p < 0.01). Systolic and diastolic blood pressure were significantly higher in micro- than in normoalbuminuric group (p < 0.05). There was a positive correlation between plasma thrombomodulin and albumin excretion rate (p = 0.013, r = 0.49), and between thrombomodulin and diastolic blood pressure (p = 0.023, r = 0.46) in diabetic patients as a whole but not in the individual groups. These findings suggest the presence of an endothelial injury in microalbuminuric patients.     

Heritability of albumin excretion rate in families of patients with Type II diabetes

Abstract Aims/hypothesis. To study whether albumin excretion rate is an inherited trait in families of patients with Type II (non-insulin-dependent) diabetes mellitus. Methods. We used three different approaches. Heritability of albumin excretion rate was studied in 267 nuclear families from the Botnia Study in Western Finland using parent-offspring regression. Albumin excretion rate was also measured in 206 non-diabetic offspring of 119 Type II diabetic parents with or without albuminuria (albumin excretion rate > 20 μg/min). Finally, albumin excretion rate was measured in altogether 652 siblings of 74 microalbuminuric and 320 normoalbuminuric probands. To study the potential confounding effect of blood pressure, the heritability of blood pressure was estimated in 718 nuclear families. Results. Using parent-offspring regression, the heritability of albumin excretion rate was about 30 %, being the strongest from mothers to sons (35–39 % resemblance). The heritability for systolic blood pressure ranged from 10 to 20 % and for diastolic blood pressure from 10 to 27 %. Offspring of albuminuric Type II diabetic parents had higher albumin excretion rates (median 5.4 [range 1.0–195] vs 4.0 [1.0–23] μg/min, p = 0.0001) and a higher frequency of microalbuminuria (11 vs 2 %, p = 0.012) than offspring of normoalbuminuric parents. Further, siblings of microalbuminuric probands had higher albumin excretion rates than siblings of normoalbuminuric probands (4.1 [0.6–14.5] vs 3.6 [0.2–14.4] μg/min, p < 0.01). Conclusion/interpretation. The data suggest that albumin excretion rate is an inherited trait in families of patients with Type II diabetes. [Diabetologia (1999) 42: 1359–1366] Received: 10 February 1999 and in revised form: 18 June 1999     

Ten-year cardiovascular mortality in relation to risk factors and abnormalities in lipoprotein composition in Type 2 (non-insulin-dependent) diabetic and non-diabetic subjects

Summary The purpose of the present study was to examine 10-year cardiovascular morbidity and mortality in patients with newly-diagnosed Type 2 (non-insulin-dependent) diabetes mellitus and non-diabetic control subjects and to evaluate the effects of general risk factors, plasma insulin, urinary albumin excretion, lipoprotein abnormalities characteristic of Type 2 diabetes and the degree of hyperglycaemia in diabetic patients on cardiovascular mortality. Furthermore, the extent to which the above-mentioned factors could contribute to the excessive cardiovascular mortality observed in diabetic patients was examined. In the years 1979–1981, altogether 133 (70 men, 63 women) newly-diagnosed patients with Type 2 diabetes and 144 (62 men, 82 women) non-diabetic control subjects aged 45–64 years were studied. Both groups were re-examined in the years 1985–1986 and 1991–1992. The impact of different factors on cardiovascular mortality was examined by univariate analyses after adjustment for age and sex and by multiple logistic regression analyses. The age-standardized total and cardiovascular mortality rates were substantially higher in diabetic men (17.8 and 15.0%, total and cardiovascular mortality, respectively p = 0.06 and NS) and women (18.5 and 16.6%, p<0.01 for both) than in non-diabetic control men (5.2 % both total and cardiovascular mortality) and women (4.2 and 2.2 %). Cardiovascular mortality was not related to the treatment modality (diet, oral drugs, insulin) at 5 years from diagnosis. Use of diuretics, beta-blocking agents or their combination at baseline did not make a significant contribution to cardiovascular mortality either. In multiple logistic regression analysis on diabetic patients, age, LDL triglycerides, smoking, blood glucose and ischaemic ECG at baseline had independent associations with cardiovascular mortality. Interestingly, urinary albumin excretion rate measured at 5-year examination also predicted 10-year cardiovascular mortality after adjustment for the effects of major risk factors including lipoprotein abnormalities, but its predictive power reduced to a nonsignificant level when the effect of plasma glucose was taken into account. The relative risk of cardiovascular mortality associated with diabetes was 8.2 after allowing for age alone, but it declined to 3.7 when all contributing factors from the baseline examination (except blood glucose) were taken into account. In conclusion, the present results indicate that LDL triglycerides and/or other changes in lipoprotein composition characteristic of Type 2 diabetes and manifesting as elevated serum triglycerides are atherogenic and they strongly predict increased cardiovascular mortality. Furthermore, it is hypothesized that the consequences of long-term hyperglycaemia could explain a large proportion of the remaining excessive cardiovascular mortality risk among Type 2 diabetic patients.     

Thrombogenic factors are related to urinary albumin excretion rate in Type 1 (insulin-dependent) and Type 2 (non-insulin-dependent) diabetic patients

Summary Parameters of haemostasis, endothelial cell markers and lipid peroxide levels were studied in 64 Type 1 (insulin-dependent) and 94 Type 2 (non-insulin-dependent) diabetic patients according to their urinary albumin excretion rate in comparison with age-matched control subjects. We determined plasma levels of fibrinogen (Clauss' method), coagulation factor VII:activity (clotting assay), factor VII antigen, protein C and S antigen, von Willebrand factor antigen,d-dimer concentration (ELISA), and lipid peroxide levels (thiobarbituric acid) in relation to urinary albumin excretion rate (RIA). Significant positive correlations were found between urinary albumin excretion rate and plasma fibrinogen (p<0.005,p<0.02), factor VII activity (p<0.0002,p<0.002), factor VII antigen (p<0.0001,p<0.001), protein C (p<0.003,p<0.05), and lipid peroxides (p<0.02,p<0.004) in Type 1 as well as in Type 2 diabetes. Von Willebrand factor (p<0.001) and protein S (p<0.0005) correlated with albuminuria only in patients with Type 1 diabetes. Although most of the haemostatic abnormalities are already found in normoalbuminuric patients, the significant positive correlations to urinary albumin excretion indicate that endothelial cell damage and coagulation disorders deteriorate with the progression of diabetic nephropathy.     

Diabetic nephropathy is associated with low-grade inflammation in Type 1 diabetic patients

Aims/hypothesis Increased concentrations of C-reactive protein and interleukin-6, a finding suggestive of the presence of inflammation, have been observed in Type 2 diabetes. In such patients, C-reactive protein was predictive of diabetic nephropathy. Studies on low-grade inflammatory markers and nephropathy in Type 1 diabetic patients have shown conflicting results. Therefore we studied whether low-grade inflammation is associated with diabetic nephropathy in Type 1 diabetic patients.Methods We divided 194 Type 1 diabetic patients into three groups from the Finnish Diabetic Nephropathy Study based upon their albumin excretion rate. Patients with normoalbuminuria (n=67) had no antihypertensive medication or signs of cardiovascular disease, while patients with microalbuminuria (n=64) or macroalbuminuria (n=63) were all treated with an angiotensin-converting enzyme inhibitor, a drug that could attenuate low-grade inflammation. As a measure of insulin sensitivity we used estimated glucose disposal rate. C-reactive protein was measured by radioimmunoassay and interleukin-6 by high sensitivity enzyme immunoassay.Results C-reactive protein was higher in micro- and macroalbuminuric patients compared to normoalbuminuric patients (normoalbuminuria 2.0±1.7, microalbuminuria 2.6±1.7, macroalbuminuria 2.9±2.5 mg/l; p=0.016), while interleukin-6 increased in parallel with the severity of the renal disease (1.9±1.5, 2.9±3.3, 3.6±3.1 ng/l; p<0.0001). In multiple regression analysis albumin excretion rate was the only variable independently associated with C-reactive protein (p=0.03), whereas albumin excretion rate (p=0.0003), HDL-cholesterol (p=0.0135) and duration of diabetes (p=0.0176) were independently associated with interleukin-6.Conclusions/interpretation Low-grade inflammatory markers are associated with diabetic nephropathy in Type 1 diabetic patients. The predictive value needs to be assessed.Abbreviations DN diabetic nephropathy - CRP C-reactive protein - eGDR estimated glucose disposal rate - FinnDiane finnish diabetic nephropathy study - MDRD modification of diet in renal disease