Proteinuria and mortality in diabetes: the WHO Multinational Study of Vascular Disease in Diabetes

Association between depressive symptoms and bone density in elderly patients with non-dialysis dependent chronic kidney disease

BACKGROUND

Depression is a disease that is commonly accompanied by elderly chronic kidney disease (CKD) patients, but when the two diseases are accompanied, etiology or combination are not well known. We aimed to evaluate the etiology of CKD and comorbid depression by investigating bone disorders that are observed in persons affected by both CKD and depression.

METHODS

We conducted a cross-sectional study with a total of 646 patients with CKD. We compared the sociodemographic factors, kidney function, markers for CKD-Mineral and Bone Disorder (CKD-MBD) and bone mineral density according to the depressive symptoms. We conducted a univariate and multivariate logistic regression analysis to calculate odd ratios (95 % confidence interval) between depressive symptoms and low bone mineral density.

RESULTS

Individuals with CKD and depressive symptoms were associated with lower level of education attained, living alone, exercising less, low 24-hour urine phosphorus, and low bone density. Depressive symptoms were significantly associated with low bone density in lowest parts (1.55 [1.06-2.29]) and in total hip (1.72 [1.17-2.53]) even after adjusting for diabetes mellitus, hypertension, kidney function, proteinuria, age, sex, smoking, and body mass index.

LIMITATIONS

A cross-sectional design was used in this study and the bone biopsy for diagnosis of CKD-MBD was not done because of invasiveness and practical difficulties.

CONCLUSION

Low bone density was associated with depressive symptoms in elderly patients with non-dialysis chronic kidney disease.

Evaluation of therapeutic effects of crocin in attenuating the progression of diabetic nephropathy: a preliminary randomized triple-blind placebo-controlled trial

Background

Diabetic nephropathy (DN) is one of the most important complications of type 2 diabetes (T2DM). Oxidative stress and inflammatory cytokines play an essential role in the development and progression of DN. Despite adopting appropriate therapies, many patients with DN progress to end-stage renal disease (ESRD). Therefore, exploring innovative strategies for better management of DN is crucial. Crocin, a natural compound found in saffron, has profound antioxidant, antifibrotic and anti-inflammatory properties. This study aimed to evaluate the therapeutic effects of crocin in attenuation of the progression of DN.

Methods

In this randomized, triple-blind, placebo-controlled clinical trial, 44 patients with T2DM and microalbuminuria were randomly assigned to receive either crocin (15 mg/day) or a placebo for 90 days. Eventually, 40 patients completed the study: 21 patients in the crocin group and 19 in the placebo group. The primary outcome was a change in urine Albumin-to-Creatinine Ratio (uACR) from baseline to the end of the treatment period. We also evaluated metabolic, anthropometric, and biochemical parameters as the secondary outcomes.

Results

The results of the present study showed that uACR increased in both groups, but the increment was not significantly higher in the crocin group compared with the placebo. Serum levels of transforming growth factor-β (TGF-β) decreased in the crocin group and increased in the placebo group, but none of these changes was significant. Crocin significantly reduced triglyceride (TG) as an important metabolic parameter (P-Value = 0.03).

Conclusion

This study has shown that crocin may be a safe and potential adjunct to conventional therapies for DN patients but because of our limitations such as short duration of the treatment period, and prescribing low doses of crocin, we could not achieve the significant level.

New Approaches to Diabetic Nephropathy from Bed to Bench

Diabetic nephropathy (DN) is the main cause of end-stage kidney disease (ESKD). DN-related ESKD has the worst prognosis for survival compared with other causes. Due to the complex mechanisms of DN and the heterogeneous presentations, unmet needs exist for the renal outcome of diabetes mellitus. Clinical evidence for treating DN is rather solid. For example, the first Kidney Disease: Improving Global Outcomes (KDIGO) guideline was published in October 2020: KDIGO Clinical Practice Guideline for Diabetes Management in Chronic Kidney Disease. In December of 2020, the International Society of Nephrology published 60 (+1) breakthrough discoveries in nephrology. Among these breakthroughs, four important ones after 1980 were recognized, including glomerular hyperfiltration theory, renal protection by renin-angiotensin system inhibition, hypoxia-inducible factor, and sodium-glucose cotransporter 2 inhibitors. Here, we present a review on the pivotal and new mechanisms of DN from the implications of clinical studies and medications.

The relationship between carotid intima-media thickness and microvascular changes in retinal zones and optic disc in patients with type 1 diabetes mellitus

PURPOSE

The aim of this study was to detect early retinal vascular changes with optical coherence tomography angiography (OCTA) in type 1 diabetes mellitus (T1DM) patients without diabetic retinopathy and to evaluate the correlation of the results with carotid intima-media thickness (IMT).

DESIGN

This is a case-control and cross-sectional study.

METHODS

This study included 38 adult patients with T1DM, and 38 age and gender-matched healthy controls. Retinal and optic disc (OD) measurements were taken using OCTA. The carotid artery IMT of each patient was measured using Doppler ultrasonography. Superficial capillary plexus (SCP) and deep capillary plexus (DCP) vessel density, foveal avascular zone (FAZ), non-flow area (NFA) and foveal density (FD) were analysed in the fovea centred 6 × 6 mm macular area. The superficial capillary plexus and DCP were also scanned centred on the peripapillary region. The correlations between OCTA measurements and carotid IMT, duration of DM and haemoglobin A1c levels in patients with T1DM were evaluated.

RESULTS

The mean values for carotid IMT were significantly higher in diabetic patients than in controls (p < 0.001). The mean values for vessel density SCP, DCP and OD were significantly lower in the diabetic group (p < 0.05). There were correlations between the carotid IMT and duration of T1DM and the evaluated parameters of OCTA.

CONCLUSION

Microvascular changes in the SCP and DCP in patients with T1DM without DR offer important data. OCTA can be used to detect early microvascular changes in patients with T1DM without DR. In addition, a relationship was found between SCP vascular dropout and carotid IMT.

Urine albumin dipstick independently predicts cardiovascular and renal outcomes among rural Thai population: a 14-year retrospective cohort study

Background

Albuminuria is an established risk marker for both cardiovascular and renal outcomes. In this study, we expected to use portable and inexpensive test strips to detect urine albumin level for risk stratification in cardiovascular and renal outcomes among rural Thai community.

Objective

To evaluate the relationship between urine albumin dipstick and cardiovascular and renal complications in rural Thai population.

Methods

We conducted a retrospective study in 635 rural Thai adults who tested urine albuminuria by using commercial urine albumin dipstick and the Micral-albumin test II strips at baseline. The subjects were divided into normoalbuminuria (albumin < 20 mg/L), microalbuminuria (albumin 20–200 mg/L), or macroalbuminuria (Urine dipstick at least 1+ or albumin > 200 mg/L). We collected data on the incidences of primary composite outcomes including cardiovascular or renal morbidity and mortality. Incident density and cox regression were analyzed to evaluate the association between albuminuria status and primary composite outcome.

Results

During an average 14-year follow-up, 102 primary composite events occurred including 59 (13.1%), 32 (20.6%) and 11 (39.3%) among 452, 155, and 28 subjects with normoalbuminuria, microalbuminuria, and macroalbuminuria, respectively. Incident densities of primary composite outcome were elevated continually according to the degree of albuminuria (9.36, 17.11 and 38.12 per 1000 person-years). Compared with the subjects without albuminuria, subjects with microalbuminuria and macroalbuminuria at baseline had higher risk for primary composite outcome in univariate model. After multivariate analysis was performed, the effect of macroalbuminuria was only persisted with 3.13-fold risk (adjusted HR 3.13; 95% CI 1.40–6.96, P= 0.005).

Conclusion

Albuminuria from semi-quantitative methods is an important factor predicting cardiovascular and renal risk among subjects in Thai rural population. Our findings support to also incorporating urine albumin dipstick into assessments of cardiovascular risk in the general population.

The potential and pitfalls of GLP-1 receptor agonists for renal protection in type 2 diabetes

Glucagon-Like Peptide-1 Receptor agonists (GLP-1 RA) offer substantial benefits for the management of glucose levels in type 2 diabetes. In addition, recent data from clinical trials have demonstrated that treatment with Glucagon-Like Peptide-1 Receptor agonists (GLP-1 RA) are also able to reduce new onset macroalbuminuria. These benefits may be consistent with the known effects of GLP-1 RA on traditional risk factors for progressive kidney disease including glucose lowering, blood pressure lowering, reduced insulin levels and weight reduction. However, emerging evidence suggests that GLP-1 RA can also have direct effects in the kidney, including inhibiting NHE3-dependent sodium reabsorption in the proximal tubule. Additional effects on the intrarenal renin angiotensin system, ischaemia/hypoxia, inflammation, apoptosis and neural signalling may also contribute to renal benefits. The extent to which these effects are mediated by the GLP-1R remains to be established. Recent studies confirm that the metabolic products of GLP-1 retain important antioxidant and anti-apoptotic activities that are GLP-1 R independent. Moreover the divergent peptide sequences of the currently available GLP-1 RA may mean that divergent reno-protective efficacy could be anticipated from different GLP-1 RA on this basis. Kidney disease is an important and deadly clinical outcome, and one worth preventing. Although both experimental and clinical data now support the possibility of renoprotective effects arising from treatment with GLP-1 RA, further work is needed to optimise these effects. A logical synergism with SGLT2 inhibition also exists, and at least in the short term, this combination approach may become the most useful way to protect the kidney in type 2 diabetes.

Review: Homocysteine, endothelial dysfunction and oxidative stress in type 1 diabetes mellitus

Type 1 diabetes is associated with an increased risk of cardiovascular disease, which cannot be fully explained by traditional risk factors. Elevated plasma homocysteine is an independent risk factor for macrovascular disease in the general population. This review examines the evidence for hyperhomocysteinaemia in patients with type 1 diabetes and describes the mechanisms that may lead to increased macrovascular susceptibility.

While reports of plasma homocysteine levels in type 1 diabetes are inconsistent, increased plasma homocysteine levels have been found in subgroups of patients with microalbuminuria, nephropathy and macrovascular disease. Although a direct causal relationship between plasma homocysteine and atherosclerosis remains to be proven, potential mechanisms of vascular damage by homocysteine include endothelial dysfunction linked to increased oxidative stress. This could contribute to the association between hyperhomocysteinaemia and macrovascular disease in type 1 diabetes.

Long Term Outcome of Femoropopliteal Bypass for Claudication and Critical Ischemia

We performed 167 femoropopliteal bypass surgeries in 151 patients (95 patients underwent above-knee bypass and 56 below-knee bypass) from December 1985 to December 2000 with the use of prosthetic graft or autologous vein graft. We compared primary patency rates between age, sex, graft material, distal anastomotic site and severity of ischemia, considering their survival rates to elucidate the long-term outcome of above-knee and below-knee femoropopliteal bypass. The 10 year patency rate for above-knee bypass was 47.4%, compared to 36.9% for below-knee ( p < 0.01). Better results were found after bypass surgery for claudicants than for critical ischemia ( p < 0.05). With regard to graft material and age categories, there were unexpectedly no statistical differences in either above-knee or below-knee anastomosis. The survival rate at 10 years in claudicants was 51.2%, compared to 15.9% with critical ischemia ( p < 0.01). Mortality was much influenced by ischemic heart disease ( p < 0.002) and the age of patient ( p < 0.05). The results after above-knee bypass had comparable patency, whereas the results after below-knee bypass were disappointing. Below-knee arterial reconstruction for claudicants should be carefully considered and might be recommended only to patients with critical ischemia.

A low baseline glomerular filtration rate predicts poor clinical outcome at 3 months after acute ischemic stroke

Background and Purpose

Chronic kidney disease (CKD) is an established risk factor for numerous cardiovascular diseases including stroke. The relationship between the baseline estimated glomerular filtration rate (eGFR) and clinical 3-month outcomes in patients with acute ischemic stroke were evaluated in this study.

Methods

This was a prospective cohort study involving a hospital-based stroke registry; 1373 patients with acute ischemic stroke were enrolled. Patients were divided into the following four groups according their eGFR (calculated using the CKD Epidemiology Collaboration equations): ≥60, 45-59, 30-44, and <30 mL/min/1.73 m². The primary endpoint of poor functional outcome was defined as 3-month death or dependency (modified Rankin Scale score ≥3); secondary endpoints were neurological deterioration (increase in National Institutes of Health Stroke Severity score of ≥4 at discharge compared to baseline) during hospitalization and in-hospital mortality.

Results

The overall eGFR was 84.5±20.8 mL/min/1.73 m² (mean±SD). The distribution of baseline renal impairment was as follows: 1,218, 82, 40, and 33 patients had eGFRs of ≥60, 45-59, 30-44, and <30 mL/min/1.73 m², respectively. At 3 months after the stroke, 476 (34.7%) patients exhibited poor functional outcome. Furthermore, a poor functional outcome occurred more frequently with increasingly advanced stages of CKD (rates of 31.9%, 53.7%, 55.0%, and 63.6% for CKD stages 1/2, 3a, 3b, and 4/5, respectively; p<0.001). Multivariate analysis revealed that a baseline eGFR of <30 mL/min/1.73m² increased the risk of a poor functional outcome by 2.37-fold (p=0.047). In addition, baseline renal dysfunction was closely associated with neurological deterioration during hospitalization and with in-hospital mortality.

Conclusions

A low baseline eGFR was strongly predictive of both poor functional outcome at 3 months after ischemic stroke and neurological deterioration/mortality during hospitalization.

Microalbuminuria as a risk predictor in diabetes: the continuing saga

OBJECTIVE The rationale for this study was to review the data on microalbuminuria (MA), an amount of albumin in the urine of 30-299 mg/day, in patients with diabetes in the context of cardiovascular risk and development of kidney disease. The objective was to review the pathophysiology of MA in patients with diabetes and review the data from trials regarding MA in the context of risk for cardiovascular events or kidney disease progression. RESEARCH DESIGN AND METHODS Data sources were all PubMed-referenced articles in English-language peer-reviewed journals since 1964. Studies selected had to have a minimum 1-year follow-up and be either a randomized trial linking MA to cardiovascular or kidney disease outcome, a meta-analysis/systematic review, or a large observational cohort study. RESULTS The data suggest that MA is a risk marker for cardiovascular events and possibly for kidney disease development. Its presence alone, however, does not indicate established kidney disease, especially if the estimated glomerular filtration rate is >60 mL/min/1.73 m(2). An increase in MA, when blood pressure and other risk factors are controlled, portends a poor prognosis for kidney outcomes over time. Early in the course of diabetes, aggressive risk factor management focused on glycemic and blood pressure goals is important to delay kidney disease development and reduce cardiovascular risk. CONCLUSIONS MA is a marker of cardiovascular disease risk and should be monitored per guidelines once or twice a year for progression to macroalbuminuria and kidney disease development, especially if plasma glucose, lipids, and blood pressure are at guideline goals.

Increased orosomucoid in urine is an independent predictor of cardiovascular and all-cause mortality in patients with type 2 diabetes at 10 years of follow-up

AIMS

To evaluate whether increased urinary orosomucoid excretion rate (UOER) is an independent predictor of cardiovascular and all-cause mortality in type 2 diabetes (T2DM) and type 1 diabetes (T1DM) at 10years of follow-up.

METHOD

We followed 430 patients with T2DM and 148 patients with T1DM until emigration, death or November 2011. We measured UOER levels in overnight urine samples.

RESULTS

Descriptive data are given in the article. In patients with T2DM and T1DM, all-cause mortality (log-rank test, p<0.01 for both types) and cardiovascular mortality (log-rank test, p<0.01 for T2DM and p=0.04 for T1DM) were significantly higher in patients with increased UOER. Normoalbuminuric patients with T2DM and increased UOER levels had higher all-cause and cardiovascular mortality (log-rank test, p<0.01 for both types). UOER was independently predictive of all-cause (HR 1.52; 95% CI 1.10-2.09; p=0.01) and cardiovascular (HR 2.31; 95% CI 1.46-3.66; p<0.01) mortality in patients with T2DM, but not in patients with T1DM.

CONCLUSION

UOER is an independent predictor of all-cause and cardiovascular mortality even in normoalbuminuric patients with T2DM at 10years of follow-up. Further studies are needed in order to evaluate the prognostic and clinical relevance.

Anaemia, diabetes and chronic kidney disease: where are we now?

Anaemia is a common finding in people with diabetes and chronic kidney disease and failure of the kidney to produce erythro-poietin in response to a falling haemoglobin concentration is a key component, correlating with the degree of albuminuria, renal dysfunction and iron deficiency. Anaemia in diabetes is associated with a number of adverse outcomes, including increased risk of all cause and cardiovascular mortality. Whether or not anaemia is a marker or mediator of adverse outcome still remains to be completely resolved. Treatment of anaemia in diabetes has quality of life benefits and reduces transfusion requirements. Correction of anaemia to normal haemoglobin concentrations is associated with significant adverse cardiovascular outcomes and is not recommended, escalating doses of erythropoiesis-stimulating agents should be avoided. The treatment of anaemia in people with diabetes and chronic kidney disease should begin with optimisation of iron stores. An aspirational haemoglobin concentration range of 10-12 g/dl with anaemia management, balances proven benefits of anaemia treatment with potential cardiovascular risk.

Emerging drugs for managing kidney disease in patients with diabetes

INTRODUCTION

The need for new approaches to manage the increasing numbers of patients with diabetes and their burden of complications is urgent. Of these, chronic kidney disease imposes some of the highest costs, both in dollars and in terms of human suffering. In individuals with diabetes, the presence and severity of kidney disease adversely affects their well-being, contributes to disease morbidity and increases their risk of a premature death.

AREAS COVERED

To collect information for the strategies previously or currently under investigation for managing kidney disease in patients with diabetes, a literature search was performed through the search engines PubMed and ClinicalTrials.gov.

EXPERT OPINION

Despite advancing knowledge on the pathogenesis of diabetic kidney disease, and promising effects in experimental models, at present there are no new drugs that come close to providing the solutions we desire for our patients. Even when used in combination with standard care, renal complications are at best only modestly reduced, at the considerable expense of additional pill burden and exposure to serious off-target effects. Some of the most exciting advances over the last decade, including thiazolidinediones, direct renin inhibitors, endothelin antagonists and most recently bardoxolone methyl have all fallen at this last hurdle. Better targeted ('smarter') drugs appear to be the best hope for renoprotective therapy.

A preliminary evaluation of bardoxolone methyl for the treatment of diabetic nephropathy

INTRODUCTION

The coordinated activation of Nrf-2-dependent signaling pathway is currently being investigated in a range of chronic diseases. Bardoxolone methyl is a potent, orally bioavailable Nrf-2 agonist. In a recent 52-week study, treatment with bardoxolone methyl improved renal function in patients with chronic kidney disease (CKD) and type 2 diabetes. This improvement was sustained for the duration of the treatment. Such agonists potentially offer new options for the complex management of renal impairment.

AREAS COVERED

A literature search was performed to analyze the pharmacokinetic (PK) and pharmacodynamic (PD) characteristics of bardoxolone methyl in both healthy volunteers and patients. Updated information about bardoxolone methyl, either after single administration or after chronic administration is also included. A special focus has been put on the putative mechanisms of action and potential toxicity profiles as well as an ongoing trials in patients with CKD and type 2 diabetes.

EXPERT OPINION

The development of an agent that leads to sustained improvement in renal function comes as a welcome relief to the millions of individuals with diabetes and CKD. However, much remains to be established regarding its actions in a complex and pleiotropic signalling cascade. Other triterpenoids with different PK/PD profiles are currently under development.

Estimated Creatinine Clearance, Homocysteine and High Sensitivity-C-Reactive Protein Levels Determination for Early Prediction of Nephropathy and Atherosclerosis Risk In Type 2 Diabetic Patients

Type 2 diabetes mellitus (T2D) patients are increased risk for cardiovascular disease (CVD) and chronic kidney disease (CKD). Many studies had demonstrated that CKD is significantly associated with CVD. We aim to indicate the using estimated creatinine clearance (eCrCl), homocysteine (tHcy), and high sensitivity-C-reactive protein (hs-CRP) levels, may have an impact on the interpretation risk for nephropathy and CVD. eCrCl was using the Cockroft-Gault formula, eCrCl levels were stratified according to the Kidney Disease Outcome Quality Initiative definition. We measured serum tHcy, hs-CRP, and the other biochemical variables in 54 T2D patients compared with 40 age matched healthy controls (NDM). T2D patients were significantly lower eCrCl than NDM (P < 0.05). T2D patients also showed significantly higher in tHcy, hs-CRP, and MDA levels than NDM subjects (P < 0.05). The eCrCl was significantly correlated with tHcy and hs-CRP levels in T2D patients (r = -0.504, P < 0.001; r = -0.282, P = 0.047). eCrCl had an impact on interpretation for CKD, especially in T2D patients. Decrease eCrCl concomitant with increased in tHcy, hs-CRP, and MDA levels may present a higher risk for future diabetic nephropathy and CVD.

The renoprotective actions of peroxisome proliferator-activated receptors agonists in diabetes

Pharmaceutical agonists of peroxisome proliferator-activated receptors (PPARs) are widely used in the management of type 2 diabetes, chiefly as lipid-lowering agents and oral hypoglycaemic agents. Although most of the focus has been placed on their cardiovascular effects, both positive and negative, these agents also have significant renoprotective actions in the diabetic kidney. Over and above action on metabolic control and effects on blood pressure, PPAR agonists also appear to have independent effects on a number of critical pathways that are implicated in the development and progression of diabetic kidney disease, including oxidative stress, inflammation, hypertrophy, and podocyte function. This review will examine these direct and indirect actions of PPAR agonists in the diabetic kidney and explore recent findings of clinical trials of PPAR agonists in patients with diabetes.

Risk of macrovascular disease stratified by stage of chronic kidney disease in type 2 diabetic patients: critical level of the estimated glomerular filtration rate and the significance of hyperuricemia

BACKGROUND

Although a high prevalence of macrovascular disease (MVD) has been reported in patients with stage 3 chronic kidney disease (CKD), few studies have reported its risk with respect to the underlying cause of kidney disease. This study investigated the prevalence of MVD in type 2 diabetic patients with CKD stratified by CKD stage, as defined by estimated glomerular filtration rate (eGFR), as well as the risk factors for MVD.

METHODS

1493 patients with diabetic CKD (1273 males, 220 females) were stratified by CKD stage (stage 1: 39, stage 2: 272, stage 3: 1052, stage 4: 101, stage 5: 29) based on eGFR calculated by the Japanese formula and averaged over 8 months. MVD was defined as one of the following: coronary heart disease (CHD), stroke or arteriosclerosis obliterans (ASO).

RESULTS

The prevalence of MVD was 18.6%. A significant increasing trend in MVD prevalence was observed from stage 3 (17.78%) to 4 (52.48%). According to a receiver operating characteristic curve analysis on MVD prevalence in stage 3 patients, an eGFR of 46.4 ml/min/1.73 m(2) was determined to be a critical cut-off level. Proteinuria, eGFR <60 ml/min/1.73 m(2) and hyperuricemia were independent risk factors for MVD.

CONCLUSIONS

In patients with diabetic CKD, a significant increase in MVD prevalence was observed from stage 3 to 4. An eGFR of 46.4 ml/min/1.73 m(2) is a critical level that affects MVD prevalence. From the perspective of cardiorenal association, CKD stage 3 should be divided into two substages. As hyperuricemia is related to an increased risk of MVD, uric acid control may be important in reducing MVD risk in diabetic CKD.

Smoking is associated with a high prevalence of microalbuminuria in hypertensive high-risk patients: data from I-SEARCH

BACKGROUND

Microalbuminuria (MAU) is a marker of endothelial dysfunction and a predictor of cardiovascular events. The effects of cigarette smoking on the prevalence of MAU in a high-risk population with arterial hypertension are unclear.

METHODS

The International Survey Evaluating Microalbuminuria Routinely by Cardiologists in patients with Hypertension (I-SEARCH) documented the clinical profile of 20,364 patients with arterial hypertension and cardiovascular risk factors. In this population, 13,690 patients had no history of smoking, 4,057 patients were former smokers and 2,617 patients were current smokers.

RESULTS

The prevalence of MAU was associated with the smoking status. Consumption of 1-20 cigarettes per day leads to an increase of 6.8% in the prevalence of MAU compared to non-smokers (P < 0.001). Smoking of >20 cigarettes per day was associated with a 12.5% higher prevalence of MAU compared to non-smokers, while former smokers had a 4.7% higher prevalence of MAU. Multivariable analysis revealed that smoking was independently associated with MAU [odds ratio (OR) smoking vs. non-smoking 1.16; 95% confidence interval (CI) 1.01-1.33; P < 0.05]. Particularly, a consumption of >20 cigarettes per day was associated with high odds for MAU (OR 1.33; CI 1.01-1.75; P < 0.05). Interestingly, independently of blood pressure, the use of an angiotensin receptor blocker and an ACE was associated with significantly reduced odds ratio for MAU in the smoking group, while there was no significant association in the non-smoking group.

CONCLUSION

The prevalence of MAU in hypertensive patients is higher in smokers than in non-smokers with a strong dose dependency.

Medial arterial calcification in diabetes and its relationship to neuropathy

Calcification of the media of arterial walls is common in diabetes and is particularly associated with distal symmetrical neuropathy. Arterial calcification also complicates chronic kidney disease and is an independent risk factor for cardiovascular and all-cause mortality. The term calcification is not strictly accurate because the morphological changes incorporate those of new bone formation, i.e. ossification. The processes are complex, but are closely related to those involved in bone homeostasis, and it is relevant that calcification of the arterial wall and osteopenia often co-exist. One particular factor linked to the development of arterial calcification is distal symmetrical neuropathy; indeed, it has been suggested that neuropathy explains the distal distribution of arterial calcification in diabetes. It has also been suggested that the link with neuropathy results from loss of neuropeptides, such as calcitonin gene-related peptide, which are inherently protective. The association between distal symmetrical neuropathy and calcification of the arterial wall highlights the fact that neuropathy may be an independent risk factor for cardiovascular mortality.

Retinal vessel response to flicker light in children and adolescents with type 1 diabetes mellitus and overweight or obesity

It was the goal of the trial to assess cardiovascular risk factors in children and adolescents with type 1 diabetes mellitus or overweight/obesity. All children and adolescents (n=77 [n=45 patients with diabetes mellitus, n=32 patients with overweight/obesity]) admitted to our hospital during the period from 01/07 to 31/08/2006 were included in the trial. Socio-demographic and laboratory data (age, sex, diabetes duration, BMI, BMI-SDS, HbA1c, fasting blood glucose, oGTT in patients with overweight/obesity, lipids, CRP, TSH, creatinine, and microalbuminuria) were assessed. The diameter of a retinal arterial and a venous segment was measured continuously on-line with a Dynamic Vessel Analyzer, carotid intima-media thickness (IMT) was measured, and 24-h-blood pressure monitoring was applied.

RESULTS

Flicker light stimulation induces a comparable arterial dilatation in patients with type 1 diabetes and overweight/obesity. Univariate ANOVA in patients with type 1 diabetes shows an influence of diastolic blood pressure on arterial dilatation. Other factors such as BMI, age, diabetes duration, smoking, sex, HbA1c and insulin dose/kg had no effect.

CONCLUSIONS

In children and adolescents with diabetes or overweight/obesity retinal vascular alterations seem to be more sensitive and already present before the occurrence of classic cardiovascular markers.

Simultaneous transdermal extraction of glucose and lactate from human subjects by reverse iontophoresis

This study investigated the possibility of simultaneously extracting glucose and lactate from human subjects, at the same skin location, using transdermal reverse iontophoresis. Transdermal monitoring using iontophoresis is made possible by the skin’s permeability to small molecules and the nanoporous and microporous nature of the structure of skin. The study was intended to provide information which could be used to develop a full, biosensor-based, monitoring system for multiple parameters from transdermal extraction. As a precursor to the human study, in vitro reverse iontophoresis experiments were performed in an artificial skin system to establish the optimum current waveforms to be applied during iontophoresis. In the human study, a bipolar DC current waveform (with reversal of the electrode current direction every 15 minutes) was applied to ten healthy volunteers via skin electrodes and utilized for simultaneous glucose and lactate transdermal extraction at an applied current density of 300 μA/cm². Glucose and lactate were successfully extracted through each subject’s skin into the conducting gel that formed part of each iontophoresis electrode. The results suggest that it will be possible to noninvasively and simultaneously monitor glucose and lactate levels in patients using this approach and this could have future applications in diagnostic monitoring for a variety of medical conditions.

Relationship between risk factors and mortality in type 1 diabetic patients in Europe: the EURODIAB Prospective Complications Study (PCS)

OBJECTIVE

The purpose of this study was to examine risk factors for mortality in patients with type 1 diabetes.

RESEARCH DESIGN AND METHODS

Baseline risk factors were measured in the EURODIAB Prospective Cohort Study with 2,787 type 1 diabetic patients (51% men and 49% women) recruited from 16 European countries. Mortality data were collected during a 7-year follow-up.

RESULTS

There was an annual mortality rate of 5 per 1,000 person-years in patients with type 1 diabetes (mean age at baseline 33 years, range 15-61 years); of the total 2,787 subjects, 102 died. The final multivariable model contained age at baseline (standardized hazard ratio 1.78 [95% CI 1.44-2.20]), A1C (1.18 [0.95-1.46]), waist-to-hip ratio (WHR) (1.32 [1.14-1.52]), pulse pressure (1.33 [1.13-1.58]), and non-HDL cholesterol (1.33 [1.12-1.60]) as risk factors for all-cause mortality. Macroalbuminuria (2.39 [1.19-4.78]) and peripheral (1.88 [1.06-3.35]) and autonomic neuropathy (2.40 [1.32-4.36]) were the most important risk markers for mortality. Similar risk factors were found for all-cause, non-cardiovascular disease (CVD), unknown-cause, and CVD mortality.

CONCLUSIONS

Important risk factors for the increased total and non-CVD mortality in type 1 diabetic patients are age, WHR, pulse pressure, and non-HDL cholesterol. Microvascular complications from macroalbuminuria and peripheral and autonomic neuropathy are strong risk markers for future mortality exceeding the effect of the traditional risk factors.

The effect of oral folic acid upon plasma homocysteine, endothelial function and oxidative stress in patients with type 1 diabetes and microalbuminuria

AIMS

The purpose of this study was to investigate the effect of oral folic acid supplementation upon plasma homocysteine (HCY), endothelial function and oxidative stress on patients with type 1 diabetes and microalbuminuria to test the hypothesis that oral folic acid would lower plasma HCY and thereby improve endothelial function and reduce oxidant stress in this high-risk group of patients.

METHODS

We measured plasma HCY, forearm blood flow, total antioxidant status and whole blood glutathione at baseline and after 2 months treatment with oral folic acid or placebo in 16 patients with type 1 diabetes and microalbuminuria.

RESULTS

Plasma HCY fell by 25% in the folic acid group but there was no difference in endothelial function or markers of oxidant stress in the treatment group.

CONCLUSIONS

Oral folic acid supplementation successfully lowered plasma HCY levels in patients with type 1 diabetes and microalbuminuria, however this was not associated with improvements in endothelial function or markers of oxidant stress.

PPAR Agonists and Cardiovascular Disease in Diabetes

Peroxisome proliferators activated receptors (PPARs) are ligand-activated nuclear transcription factors that play important roles in lipid and glucose homeostasis. To the extent that PPAR agonists improve diabetic dyslipidaemia and insulin resistance, these agents have been considered to reduce cardiovascular risk. However, data from murine models suggests that PPAR agonists also have independent anti-atherosclerotic actions, including the suppression of vascular inflammation, oxidative stress, and activation of the renin angiotensin system. Many of these potentially anti-atherosclerotic effects are thought to be mediated by transrepression of nuclear factor-kB, STAT, and activator protein-1 dependent pathways. In recent clinical trials, PPARalpha agonists have been shown to be effective in the primary prevention of cardiovascular events, while their cardiovascular benefit in patients with established cardiovascular disease remains equivocal. However, the use of PPARgamma agonists, and more recently dual PPARalpha/gamma coagonists, has been associated with an excess in cardiovascular events, possibly reflecting unrecognised fluid retention with potent agonists of the PPARgamma receptor. Newer pan agonists, which retain their anti-atherosclerotic activity without weight gain, may provide one solution to this problem. However, the complex biologic effects of the PPARs may mean that only vascular targeted agents or pure transrepressors will realise the goal of preventing atherosclerotic vascular disease.

Renal-related deaths in Indigenous people in Queensland, Australia

AIM

Indigenous Australians have much higher mortality than non-Indigenous Australians. We aimed to quantify the excess of deaths with a renal causal assignment among Indigenous people aged 25 years and over in Queensland, Australia, 1997-2000 and their distribution by remoteness.

METHODS

Both underlying and associated causes defined by ICD, 10(th) edition, were examined. Mortality rates were standardized to the concurrent non-Indigenous population.

RESULTS

In Indigenous people, standardized mortality ratios with a renal assignment of death by remoteness of residence were 194% (Major City and Inner Regional), 439% (Outer Regional and Remote) and 782% (Very Remote). Of all these deaths with a renal assignment, only 18% had a renal assignment as the underlying cause. Diabetes and cardiovascular disease were frequent concomitant causes in deaths with a renal assignment.

CONCLUSION

The Indigenous population in Queensland has elevated rates of renal deaths compared with the non-Indigenous population. This disparity increases markedly with increasing remoteness of residence. Reliance on underlying causes of death alone greatly underestimates the association of renal disease with deaths in this population.

Chronic kidney disease as a risk factor for coronary artery disease in Chinese with type 2 diabetes

BACKGROUND

Chronic kidney disease (CKD) is associated with cardiovascular disease (CVD) in the general population. We investigated the effects of renal function on coronary artery disease (CAD) in Chinese with type 2 diabetes who have a high risk of developing diabetic nephropathy but who may have a low risk of developing CAD.

METHODS

We recruited a total of 2,434 Chinese with type 2 diabetes (1,078 men and 1,356 women) and diagnosed CAD by history or with an abnormal electrocardiogram (coronary probable or possible by Minnesota codes). Renal function was evaluated by serum creatinine (SCr) levels, estimated glomerular filtration rate (eGFR) (calculated by the abbreviated Modification of Diet in Renal Disease Study Croup formula) and urinary albumin/creatinine ratio (ACR).

RESULTS

We found that patients with CAD were older, had higher SCr levels and body mass index (BMI), and had lower serum high-density lipoprotein cholesterol (HDL-c) levels. After adjusting for age, BMI, blood pressure, glycosylated hemoglobin, cholesterol, LDL-c, HDL-c, and triglycerides, we found that SCr levels >1.5 mg/dl, eGFR <60 ml/min, and urinary ACR >30 mg/g were independent risk factors for CAD in diabetic men, and that SCr levels >1.4 mg/dl and eGFR <60 ml/min were independently associated with CAD in women.

CONCLUSION

Our findings indicate that Chinese with type 2 diabetes and CKD are likely to have had CAD previously and CKD is 'CVD risk state' in diabetic Chinese.

Genome-wide scans for diabetic nephropathy and albuminuria in multiethnic populations: the family investigation of nephropathy and diabetes (FIND)

The Family Investigation of Nephropathy and Diabetes (FIND) was initiated to map genes underlying susceptibility to diabetic nephropathy. A total of 11 centers participated under a single collection protocol to recruit large numbers of diabetic sibling pairs concordant and discordant for diabetic nephropathy. We report the findings from the first-phase genetic analyses in 1,227 participants from 378 pedigrees of European-American, African-American, Mexican-American, and American Indian descent recruited from eight centers. Model-free linkage analyses, using a dichotomous definition for diabetic nephropathy in 397 sibling pairs, as well as the quantitative trait urinary albumin-to-creatinine ratio (ACR), were performed using the Haseman-Elston linkage test on 404 microsatellite markers. The strongest evidence of linkage to the diabetic nephropathy trait was on chromosomes 7q21.3, 10p15.3, 14q23.1, and 18q22.3. In ACR (883 diabetic sibling pairs), the strongest linkage signals were on chromosomes 2q14.1, 7q21.1, and 15q26.3. These results confirm regions of linkage to diabetic nephropathy on chromosomes 7q, 10p, and 18q from prior reports, making it important that genes underlying these peaks be evaluated for their contribution to nephropathy susceptibility. Large family collections consisting of multiple members with diabetes and advanced nephropathy are likely to accelerate the identification of genes causing diabetic nephropathy, a life-threatening complication of diabetes.

Low-grade albuminuria and cardiovascular risk : what is the evidence?

Microalbuminuria (MA), conventionally defined as a urinary albumin excretion (UAE) of 30-300 mg/day, is recognised as a marker of endothelial dysfunction. Furthermore, it represents an established risk factor for cardiovascular morbidity and mortality and for end-stage renal disease in individuals with an adverse cardiovascular risk profile. It is common in the general population, particularly in patients with diabetes mellitus or arterial hypertension. There is growing evidence from prospective observational trials that UAE levels well below the current MA threshold ("lowgrade MA") are also associated with an increased risk of incident cardiovascular disease and allcause mortality. Even in apparently healthy individuals (without diabetes or hypertension), such an association has been shown. As albuminuria screening assays that are reliable even in the lower ranges are commercially available, there may be an important clinical role for MA in disease screening, comparable to the role of blood pressure and lipid screening. MA is modifiable, and the inhibition of the renin-angiotensin system by ACE inhibitors and AT1 receptor antagonists has been shown to result in a lower incidence of cardiovascular events.

Blood pressure lowering for the prevention and treatment of diabetic kidney disease

The current pandemic of diabetes mellitus will inevitably be followed by an epidemic of chronic kidney disease. It is anticipated that 25-40% of patients with type 1 diabetes and 5-40% of patients with type 2 diabetes will ultimately develop diabetic kidney disease. The control of blood pressure represents a key component for the prevention and management of diabetic nephropathy. There is a strong epidemiological connection between hypertension in diabetes and adverse outcomes in diabetes. Hypertension is closely linked to insulin resistance as part of the 'metabolic syndrome'. Diabetic nephropathy may lead to hypertension through direct actions on renal sodium handling, vascular compliance and vasomotor function. Recent clinical trials also support the utility of blood pressure reduction in the prevention of diabetic kidney disease. In patients with normoalbuminuria, transition to microalbuminuria can be prevented by blood pressure reduction. This action appears to be significant regardless of whether patients have elevated blood pressure or not. The efficacy of ACE inhibition appears to be greater than that achieved by other agents with a similar degree of blood pressure reduction; although large observational studies suggest the risk of microalbuminuria may be reduced by blood pressure reduction, regardless of modality. In patients with established microalbuminuria, ACE inhibitors and angiotensin receptor antagonists (angiotensin receptor blockers [ARBs]) consistently reduce the risk of progression from microalbuminuria to macroalbuminuria, over and above their antihypertensive actions. The clinical utility of combining these strategies remains to be established. In patients with overt nephropathy, blood pressure reduction is associated with reduced urinary albumin excretion and, subsequently, a reduced risk of renal impairment or end stage renal disease. In addition to actions on systemic blood pressure, it is now clear that ACE inhibitors and ARBs also reduce proteinuria in patients with diabetes. This anti-proteinuric activity is distinct from other antihypertensive agents and diuretics. Although there is a clear physiological rationale for blockade of the renin angiotensin system, which is strongly supported by clinical studies, to achieve the optimal lowering of blood pressure, particularly in the setting of established diabetic renal disease, a number of different antihypertensive agents will always be needed. In the end, the choice of agents should be individualised to achieve the maximal tolerated reduction in blood pressure and albuminuria. Ultimately, no matter how it is achieved, so long as it is achieved, renal risk can be reduced by agents that lower blood pressure and albuminuria.

All-cause and cardiovascular mortality in diabetic subjects increases significantly with reduced estimated glomerular filtration rate (eGFR): 10 years' data from the South Tees Diabetes Mortality study

AIMS

To investigate the association between estimated glomerular filtration rate (eGFR) and total and cardiovascular mortality in a population-based cohort of diabetic subjects.

METHODS

A longitudinal study using a population-based district diabetes register comprising 3288 subjects in South Tees, UK. The eGFR was calculated using the Modification of Diet in Renal Disease (MDRD) study equation. Patients were stratified by baseline eGFR into five stages as per the National Kidney Foundation guidelines: Stage 1, eGFR > 90; Stage 2, eGFR 60-89; Stage 3, eGFR 30-59; Stage 4, eGFR 15-29; and Stage 5, eGFR < 15 ml/min per 1.73 m(2). Main outcome was all-cause and cardiovascular mortality between 1 January 1994 and 31 July 2004.

RESULTS

At baseline, mean age (58.4 years) differed between groups. Persons with lower eGFR were older (P < 0.001). Thirty-six percent (n = 1193, males 56%) had died by 10 years (cardiovascular cause in 60%). Median follow-up was 10.5 years amounting to 28 342 person years. Stages 4 and 5 (eGFR <or= 29 ml/min per 1.73 m(2)) were amalgamated for mortality analysis. Total and cardiovascular mortality increased with reduced eGFR. Adjusted hazard ratios (HR) [95% confidence interval (CI)] for all-cause mortality comparing groups 2 and 3, and 4 and 5 combined with group 1 were 1.28 (1.02, 1.60), 2.58 (2.05, 3.25) and 6.42 (4.25, 9.71), respectively. Adjusted HRs (95% CI) for mortality due to circulatory disease comparing groups 2 and 3, and 4 and 5 combined with group 1 were 1.50 (1.10, 2.06), 3.32 (2.41, 4.58) and 7.99 (4.69, 13.62), respectively.

CONCLUSIONS

In diabetic subjects, mortality increases significantly with reduced GFR. Low eGFR identifies patients at high risk of cardiovascular mortality who should be targeted for aggressive risk factor modification.

Plasma homocysteine, oxidative stress and endothelial function in patients with Type 1 diabetes mellitus and microalbuminuria

AIMS

The purpose of this study was to examine the associations between endothelial function, plasma homocysteine and oxidative stress in patients with Type 1 diabetes mellitus (DM) and microalbuminuria compared with DM patients with normoalbuminuria and non-diabetic control subjects. We wished to test the hypothesis that increased cardiovascular risk in patients with Type 1 diabetes and microalbuminuria may be in part as a result of hyperhomocysteinaemia-mediated oxidative stress leading to impaired endothelial function.

METHODS

We measured forearm blood flow, total plasma homocysteine, total antioxidant status (TAOS) and whole blood glutathione in 31 DM patients, 16 with microalbuminuria and 15 with normoalbuminuria, and 15 non-diabetic control subjects.

RESULTS

Plasma homocysteine levels were significantly higher in the microalbuminuric diabetic patients compared with the normoalbuminuric patients and the control subjects. TAOS was significantly lower in the micoalbuminuric and normoalbuminuric diabetic patients compared with the control subjects, although TAOS levels were similar in both groups of diabetic patients. There was no difference in forearm blood flow between the groups and no association between measured endothelial function and antioxidant defence/oxidative stress and homocysteine in each group. There was no association between plasma total homocysteine and TAOS or whole blood glutathione within the groups.

CONCLUSIONS

We have found mild hyperhomocysteinaemia in microalbuminuric DM patients compared with normoalbuminuric DM patients and non-diabetic subjects and some evidence for reduced antioxidant defence in DM patients. These findings add to our understanding of the increased risk of vascular disease in patients with Type 1 diabetes.

End-stage renal disease risk equations for Hong Kong Chinese patients with type 2 diabetes: Hong Kong Diabetes Registry

AIMS/HYPOTHESIS

The objective of the study was to investigate risk factors and develop risk equations for end-stage renal disease (ESRD) in Chinese patients with type 2 diabetes.

SUBJECTS AND METHODS

A prospective cohort of 4,438 patients with type 2 diabetes mellitus and without ESRD (median observation period 2.9 years, interquartile range 1.6-4.1 years) was included in the analysis. The end-point (ESRD) was defined by: (1) death due to diabetes with renal manifestations or renal failure; (2) hospitalisation due to renal failure; (3) estimated GFR (eGFR) <15 ml min(-1) 1.73 m(-2). Cox proportional hazards regression was used to develop risk equations. The data were randomly and evenly divided into the training data for development of the risk equations and the test data for validation. The validation was performed using the area under the receiver operating characteristic curve (aROC), which takes into account follow-up time and censoring.

RESULTS

During the observation period, 159 patients or 12.45 per 1,000 person-years (95% CI 10.52-14.37 per 1,000 person-years) developed ESRD. Known duration of diabetes, systolic blood pressure, log(10) total cholesterol:HDL cholesterol ratio and retinopathy were significant predictors of ESRD. After further adjusting for eGFR, log(10) spot albumin:creatinine ratio (ACR) and haematocrit, only eGFR, haematocrit and log(10) ACR remained as independent predictors of ESRD. The risk equation derived from these three independent predictors had good discrimination, with an aROC of 0.97.

CONCLUSIONS/INTERPRETATION

Estimated GFR, haematocrit and ACR were independent predictors of ESRD and the derived risk equation performed well in Chinese patients with type 2 diabetes.

Low risk of overt nephropathy after 24 yr of childhood-onset type 1 diabetes mellitus (T1DM) in Norway

AIM

To estimate the risk of diabetic nephropathy and associated risk factors in a nationwide cohort of childhood-onset type 1 diabetes mellitus (T1DM) and 19-30 yr of diabetes duration.

METHODS

Patients diagnosed with childhood-onset T1DM (<15 yr) from 1973 through 1982, who previously (1989-1990) participated in a clinical examination to assess diabetic complications, were invited for a new examination in 2002-2003. Of 355 eligible patients, 299 participated (84.2%), and complete urine samples for evaluation of albuminuria were obtained from 295 patients, with a mean age of 33 yr (range 20.9-44.0) and mean diabetes duration of 24 yr (range 19.3-29.9). Persistent microalbuminuria and overt nephropathy [albumin excretion rate (AER) 15-200 microg/min and AER > 200 microg/min, respectively] in at least two out of three consecutive overnight urine samples were defined as diabetic nephropathy.

RESULTS

Overt nephropathy was found in 7.8% [95% confidence interval (CI) 4.7-10.9] and persistent microalbuminuria in 14.9% (95% CI 10.8-19.0) of the subjects. Hemoglobin A1c (HbA1c) (p = 0.001), systolic blood pressure (BP) (p = 0.002), total cholesterol (p = 0.019), and C-reactive protein (CRP) (p = 0.019) were associated with diabetic nephropathy. Significant predictors in 1989-1990 for the development of diabetic nephropathy in 2002-2003 were HbA1c (p < 0.001), AER (p = 0.007), and cholesterol (p = 0.022).

CONCLUSIONS

In a subgroup of patients diagnosed with childhood-onset T1DM in 1973-1982, 7.8% had overt nephropathy after 19-30 yr of diabetes duration, which is low compared with studies from other countries. HbA1c, systolic BP, total cholesterol, and CRP were each independently associated with diabetic nephropathy.

The burden of chronic kidney disease in Australian patients with type 2 diabetes (the NEFRON study)

OBJECTIVE

To estimate the frequency of chronic kidney disease (CKD) in a clinic-based sample of patients with type 2 diabetes in the setting of Australian primary care.

DESIGN, SETTING AND PARTICIPANTS

Expressions of interest were invited from all registered general practitioners in Australia: 500 GP investigators were randomly selected from each stratum (state and urban versus rural location), proportional to the census population, and asked to recruit and provide data for 10-15 consecutively presenting adults with type 2 diabetes between April and September 2005.

MAIN OUTCOME MEASURES

Estimated glomerular filtration rate (eGFR) less than 60 mL/min/1.73 m(2) and evidence of kidney damage on urinalysis (eg, microalbuminuria).

RESULTS

348 GP investigators submitted data for 3893 individuals with type 2 diabetes (52% men; median age, 66 years). Almost one in every four patients consulting their GPs had an eGFR < 60 mL/min/1.73 m(2) (23.1%; 95% CI, 21.8%-24.5%). More than one in three had an elevated urinary albumin-creatinine ratio (ACR) (34.6%; 95% CI, 33.3%-35.9%). There was an overlap of 10.4% of patients with both an eGFR < 60 mL/min/1.73 m(2) and an elevated urinary ACR, meaning that almost one in two patients with type 2 diabetes consulting their GPs (47.1%; 95% CI, 45.8%-48.4%) had CKD. CKD was significantly more common in women, in older people, and in individuals with established macrovascular disease.

CONCLUSION

CKD is a common complication of type 2 diabetes, found in about half of all patients with type 2 diabetes consulting their GPs. Efforts to increase the recognition of CKD will lead to improved care, and possibly survival, of patients with type 2 diabetes.

Microalbuminuria

Microalbuminuria, originally described more than 3 decades ago as a predictor of nephropathy in patients who had type 1 diabetes mellitus and associated with higher cardiovascular risk, is now linked with increased risk for cardiovascular events rather than progression to end-stage kidney disease. This article reviews the role of microalbuminuria in the context of atherosclerotic vascular disease. It presents the methods for microalbuminuria assessment in clinical practice, its relations with other cardiovascular risk factors, and the pathophysiologic associations between microalbuminuria and vascular damage. In addition, this article discusses the prognostic significance of microalbuminuria for cardiovascular disease as well as existing therapeutic interventions for reducing urine albumin excretion in patients who are at high cardiovascular risk.

Kidney disease and cardiovascular disease: implications of dyslipidemia

Cardiovascular complications are common inpatients with kidney disease. Regulating the lipid levels in these patients is important so that the risks of kidney and cardiovascular complications can be minimized. Lipid regulation decreases the incidence of coronary vascular events and other vascular complications in patients with kidney disease; however, whether lipid regulation slows progression of kidney disease is not yet known. Additional studies of the implications of dyslipidemia in patients with kidney disease are needed.

Cardiovascular risk in chronic renal disease and transplantation prevention and management

Cardiovascular disease (CVD) is the single best predictor of mortality in patients with chronic kidney disease and in kidney transplant recipients. These populations are considered to be at extraordinarily high risk for CVD and its complications. On the other hand, renal dysfunction should be considered as a CVD risk factor. The management of CVD in patients with chronic kidney disease is a special challenge for clinicians. In this article, major risk factors for CVD are presented, as well as diagnosis of coronary artery disease, acute coronary syndromes, its treatment modalities (pharmacological therapy and coronary revascularisation procedures), and outcomes in patients with chronic renal failure and kidney allograft recipients.

Importance of baseline distribution of proteinuria in renal outcomes trials: lessons from the reduction of endpoints in NIDDM with the angiotensin II antagonist losartan (RENAAL) study

A key issue in the analysis of outcome trials is the adjustment for baseline covariates that influence the primary outcome. Imbalance of an important covariate between treatment groups at baseline is of considerable concern if one treatment group is favored over another with respect to the hypothesis testing outcome. With the use of the Reduction of Endpoints in NIDDM with the Angiotensin II Antagonist Losartan (RENAAL) study database as an example, the influence of baseline proteinuria on the primary composite endpoint, ESRD, and ESRD or death after adjusting for baseline proteinuria as a continuous covariate was examined. Increasing baseline proteinuria was associated with increased risk for renal events, confirming that proteinuria is an important covariate for renal outcomes. When the randomization was stratified according proteinuria <2000 mg/g or >/=2000 mg/g, within the higher proteinuria stratum (>/=2000 mg/g), patients in the losartan group had a higher baseline mean proteinuria value. When the imbalance was adjusted, an increase in the magnitude and the significance of the risk reduction with losartan for each outcome was observed. No apparent interaction between treatment effect and baseline proteinuria was found, and there was no heterogeneity in the treatment response in patients with different baseline proteinuria levels. After proteinuria was adjusted as a continuous variable, greater treatment effects were observed in the RENAAL study. This effect was due solely to the imbalance in baseline proteinuria. Considering the importance of proteinuria as a risk factor, adjustment for baseline proteinuria as a continuous covariate should be prespecified in the design and analysis of clinical trials involving renal outcomes, even when patients are stratified on the basis of level of proteinuria.

Traditional and nontraditional cardiovascular risk factors in chronic kidney disease

Chronic kidney disease (CKD) is public health problem, with as many as 20 million individuals affected in the United States. Patients with CKD should be considered in the highest-risk group for development of cardiovascular disease (CVD), and aggressive treatment of traditional and nontraditional risk factors should be instituted. Additional randomized controlled trials are urgently needed to evaluate potential treatments in this population. This article focuses attention on the major modifiable cardiovascular risk factors in CKD.

Associations of mortality and diabetes complications in patients with type 1 and type 2 diabetes: early treatment diabetic retinopathy study report no. 27

OBJECTIVE

Diabetes is a leading cause of morbidity and mortality. The purpose of this study is to assess the associations between diabetes complications and mortality in the Early Treatment Diabetic Retinopathy Study (ETDRS).

RESEARCH DESIGN AND METHODS

We examined demographic, clinical, and laboratory characteristics of the 3,711 subjects enrolled in the ETDRS, a randomized controlled clinical trial designed to evaluate the role of laser photocoagulation and aspirin therapy for diabetic retinopathy. The outcome assessed was all-cause mortality. Multivariable Cox proportional hazards regression was used to assess associations between diabetes complications and mortality for type 1 and type 2 diabetes separately.

RESULTS

The 5-year estimates of all-cause mortality were 5.5 and 18.9% for patients with type 1 and type 2 diabetes, respectively. In patients with type 1 diabetes, amputation (hazard ratio [HR] 5.08 [95% CI 2.06-12.54]) and poor visual acuity (1.74 [1.10-2.75]) remained significantly associated with mortality, after adjusting for other diabetes complications and baseline characteristics. In patients with type 2 diabetes, macrovascular disease and worsening levels of nephropathy, neuropathy, retinopathy, and visual acuity are associated with progressively increasing risks of mortality, after controlling for other baseline risk factors.

CONCLUSIONS

Amputation is the strongest predictor for mortality in patients with type 1 diabetes. All complications independently predict mortality in patients with type 2 diabetes. There is an increased risk for mortality as the degree of each complication worsens. Additional studies are needed to investigate the effectiveness of tertiary prevention to decrease mortality in these patients.

Renal damage in patients with Type 2 diabetes: a strong predictor of mortality

AIMS

(i) To compare mortality rates in a cohort of Type 2 diabetic patients with those of the general population; (ii) to assess the prognostic role of pre-existing chronic conditions; (iii) to evaluate the impact of different severity of renal damage on mortality.

METHODS

All 3892 patients with Type 2 diabetes attending our Diabetic Clinic during 1995 and alive on 1 January 1996 were identified and followed for 4.5 years. Information on vital status (100% complete) and causes of death (98.5% complete) for 599 deceased subjects was derived from death certificates.

RESULTS

In comparison with the general population, standardized mortality ratios (x 100) were: 125 (95% confidence interval 104-148) in patients aged < 75 and 85 (75-95) in patients > or = 75 years. Cardiovascular diseases and diabetes were responsible for most of the excess deaths. In a Cox-proportional hazard model, renal damage was a powerful predictor of death (hazard ratio = 2.39; 95% confidence intervals = 2.00-2.85). The severity of renal damage was associated with increasing hazard ratios for death from all-cause mortality and from specific causes (especially coronary artery disease, other cardiovascular causes and diabetes) after multiple adjustments. Other significant predictors of death were: greater age, glycated haemoglobin, smoking, lower body mass index, pre-existing coronary and peripheral artery disease and known co-morbidity (cirrhosis and cancer).

CONCLUSIONS

Renal damage of any severity is significantly associated with subsequent mortality from all causes and from cardiovascular diseases. These associations are not confounded by pre-existing co-morbidity or coronary diseases.

Usefulness of total cholesterol/HDL-cholesterol ratio in the management of diabetic dyslipidaemia

AIMS

Our aim was to evaluate the usefulness of the total cholesterol/HDL-cholesterol ratio (TC/HDL) in predicting the cardiovascular risk of Type 2 diabetic patients.

METHODS

Prospective cohort study with inclusion of 418 Type 2 diabetic individuals with follow-up until the appearance of a cardiovascular event. The predictive power of updated mean lipid values during follow-up was analysed by means of Cox proportional hazard models. An estimate was made of the relative risk (RR) conferred by high levels of TC/HDL stratified by LDL-cholesterol levels.

RESULTS

Sixty-six cardiovascular events occurred during an average follow-up of 4.7 years (sd 1.5). The main lipid predictor of vascular events was mean TC/HDL ratio [hazard ratio (HR) = 1.46; 95% confidence interval (CI) 1.25, 1.7; P < 0.0001]. In the multivariate model with simultaneous inclusion of mean TC/HDL and mean LDL-cholesterol, both were significant predictors of cardiovascular disease [HR (1 unit) = 1.37; 95% CI 1.16, 1.62; P = 0.0003 and HR (1 mmol/l) = 1.5; 95% CI 1.04, 2.18; P = 0.03, respectively]. The LDL adjusted RR for cardiovascular events due to high TC/HDL ratio, with 4.5 cut-off point, was 2.5 (95% CI 1.4, 4.3; P = 0.0007). For the stratum of subjects with average LDL cholesterol < 3.5 mmol/l, RR was 1.2 (95% CI 0.5, 2.8; P = NS) and for the stratum of average LDL cholesterol > 3.5 mmol/l, RR was 4 (95% CI 1.8, 9; P = 0.00013), with heterogeneity among strata (P = 0.044).

CONCLUSIONS

It could be useful to include the TC/HDL ratio in treatment guides for diabetic dyslipidaemia, given their high predictive value and strong interaction with LDL cholesterol.

Mild renal insufficiency as a cardiovascular risk factor in non-proteinuric type II diabetes

OBJECTIVES

To evaluate cardiovascular risk according to baseline renal function in a group of non-proteinuric type II diabetic patients.

MATERIAL AND METHODS

Prospective study with a follow-up of 423 non-proteinuric type II diabetic patients with creatinine <150 micromol/l for an average of 4.7 years (S.D. 1.55). Creatinine clearance (CC) was estimated using the Cockcroft-Gault formula and expressed in millilitre per minute. The hazard ratio (HR) associated with each millilitre per minute decrease in baseline CC on fatal or non-fatal cardiovascular events and total mortality was evaluated using the Cox regression model.

RESULTS

Baseline creatinine was 89 micromol/l (S.D. 15.9) and CC was 69.5 ml/min (S.D. 20). There were 63 cardiovascular events (15 unstable angina, 10 non-fatal myocardial infarctions, 25 non-fatal strokes, two amputations, nine fatal myocardial infarctions and two fatal strokes) and 39 total deaths (11 for cardiovascular causes). The cardiovascular event rate was 31.7/1000 patient-years and the total mortality rate was 19.6/1000 patient-years. The independent predictors of cardiovascular events were: CC (HR=1.035; confidence interval (CI) 95% 1.02-1.05; P<0.0001), total cholesterol/HDL cholesterol ratio (HR=1.25; CI 95% 1.1-1.4; P=0.0008), baseline coronary heart disease (HR=2.05; CI 95% 1.07-3.9; P=0.04) and baseline microalbuminuria (HR=2.3; CI 95% 1.3-3.8; P=0.003). The independent total mortality predictors were: CC (HR=1.04; CI 95% 1.02-1.08; P<0.0001), male (HR=2.1; CI 95% 1.1-4; P=0.027) and baseline microalbuminuria (HR=2.1; CI 95% 1.1-4;P=0.03).

CONCLUSIONS

Mild renal insufficiency increases cardiovascular risk in non-proteinuric patients with type II diabetes.

Differential effects of calcium antagonist subclasses on markers of nephropathy progression

BACKGROUND

Numerous studies suggest that the dihydropyridine calcium antagonists (DCAs) and nondihydropyridine calcium antagonists (NDCAs) have differential antiproteinuric effects. Proteinuria reduction is a correlate of the progression of renal disease. In an earlier systematic review, calcium antagonists were shown as effective antihypertensive drugs, but there was uncertainty about their renal benefits in patients with proteinuria and renal insufficiency.

METHODS

A systematic review was conducted to assess the differential effects of DCAs and NDCAs on proteinuria in hypertensive adults with proteinuria, with or without diabetes, and to determine whether these differential effects translate into altered progression of nephropathy. Studies included in the review had to be randomized clinical trials with at least 6 months of treatment, include a DCA or NDCA treatment arm, have one or more renal end points, and have been initiated after 1986. Summary data were extracted from 28 studies entered into two identical but separate databases, which were compared and evaluated by independent reviewers. The effects of each drug class on blood pressure (N= 1338) and proteinuria (N= 510) were assessed.

RESULTS

After adjusting for sample size, study length, and baseline value, there were no statistically significant differences in the ability of either class of calcium antagonist to decrease blood pressure. The mean change in proteinuria was +2% for DCAs and -30% for NDCAs (95% CI, 10% to 54%, P= 0.01). Consistently greater reductions in proteinuria were associated with the use of NDCAs compared with DCAs, despite no significant differences in blood pressure reduction or presence of diabetes.

CONCLUSION

This analysis supports (1) similar efficacy between subclasses of calcium antagonists to lower blood pressure, and (2) greater reductions in proteinuria by NDCAs compared to DCAs in the presence or absence of diabetes. Based on these findings, NDCAs, alone or in combination with an angiotensin-converting enzyme (ACE) inhibitor or an angiotensin receptor blocker (ARB), are suggested as preferred agents to lower blood pressure in hypertensive patients with nephropathy associated with proteinuria.