Non-proteinuric pathways in loss of renal function in patients with type 2 diabetes.

Largely on the basis of data from patients with type 1 diabetes, the natural history of diabetic renal disease has been classified as a sequence of three stages: normoalbuminuria, microalbuminuria, and macroalbuminuria. Progressive decline of glomerular filtration rate (GFR) was thought to parallel the onset of macroalbuminuria (overt nephropathy), whereas glomerular hyperfiltration was deemed a hallmark of early disease. However, researchers have since shown that albuminuria is a continuum and that GFR can start to decline before progression to overt nephropathy. In addition to proteinuria, other risk factors might contribute to GFR deterioration including female sex, obesity, dyslipidaemia (in particular hypertriglyceridaemia), hypertension, and glomerular hyperfiltration, at least in a subgroup of patients. This phenomenon could explain why patients with type 2 diabetes can have renal insufficiency even before the onset of overt nephropathy, and might also suggest why the heterogeneous phenotype of type 2 diabetic renal disease does not necessarily associate with typical histological lesions of diabetic renal disease, unlike in type 1 diabetic renal disease. Patients with renal insufficiency but without albuminuria are usually excluded from randomised clinical trials in overt nephropathy, thus optimum treatment for this group of patients is unknown. The wide inter-patient variability of the disease probably needs individually tailored intervention.

The effects of GLP-1 analogues, DPP-4 inhibitors and SGLT2 inhibitors on the renal system.

Diabetic nephropathy (DN) affects an estimated 20%-40% of patients with type 2 diabetes mellitus (T2DM). Key modifiable risk factors for DN are albuminuria, anaemia, dyslipidaemia, hyperglycaemia and hypertension, together with lifestyle factors, such as smoking and obesity. Early detection and treatment of these risk factors can prevent DN or slow its progression, and may even induce remission in some patients. DN is generally preceded by albuminuria, which frequently remains elevated despite treatment in patients with T2DM. Optimal treatment and prevention of DN may require an early, intensive, multifactorial approach, tailored to simultaneously target all modifiable risk factors. Regular monitoring of renal function, including urinary albumin excretion, creatinine clearance and glomerular filtration rate, is critical for following any disease progression and making treatment adjustments. Dipeptidyl peptidase (DPP)-4 inhibitors and sodium-glucose cotransporter 2 (SGLT2) inhibitors lower blood glucose levels without additional risk of hypoglycaemia, and may also reduce albuminuria. Further investigation of the potential renal benefits of DPP-4 and SGLT2 inhibitors is underway.

Fatty kidney: emerging role of ectopic lipid in obesity-related renal disease.

The global increase in chronic kidney disease (CKD) parallels the obesity epidemic. Obesity conveys a gradual but independent risk of progression of CKD that seems irrespective of the underlying nephropathy. Obesity has been associated with a secondary focal segmental glomerulosclerosis coined obesity-related glomerulopathy (ORG). Pathways through which obesity might cause renal disease are not well understood, and early clinical biomarkers for incipient ORG or renal relevant obesity are currently lacking. Recent human and experimental studies have associated ectopic lipid accumulation in the kidney (fatty kidney) with obesity-related renal disease. There is enough growing insight that ectopic lipid--the accumulation of lipid in non-adipose tissue--is associated with structural and functional changes of mesangial cells, podocytes, and proximal tubular cells to propose the development of ORG as a maladaptive response to hyperfiltration and albuminuria. Recent advances in metabolic imaging might validate ectopic lipid as a biomarker and research aid, to help translate novel therapeutics from experimental models to patients.

Intensive glucose control improves kidney outcomes in patients with type 2 diabetes.

The effect of intensive glucose control on major kidney outcomes in type 2 diabetes remains unclear. To study this, the ADVANCE trial randomly assigned 11,140 participants to an intensive glucose-lowering strategy (hemoglobin A1c target 6.5% or less) or standard glucose control. Treatment effects on end-stage renal disease ((ESRD), requirement for dialysis or renal transplantation), total kidney events, renal death, doubling of creatinine to above 200 µmol/l, new-onset macroalbuminuria or microalbuminuria, and progression or regression of albuminuria, were then assessed. After a median of 5 years, the mean hemoglobin A1c level was 6.5% in the intensive group, and 7.3% in the standard group. Intensive glucose control significantly reduced the risk of ESRD by 65% (20 compared to 7 events), microalbuminuria by 9% (1298 compared to 1410 patients), and macroalbuminuria by 30% (162 compared to 231 patients). The progression of albuminuria was significantly reduced by 10% and its regression significantly increased by 15%. The results were almost identical in analyses taking account of potential competing risks. The number of participants needed to treat over 5 years to prevent one ESRD event ranged from 410 in the overall study to 41 participants with macroalbuminuria at baseline. Thus, improved glucose control will improve major kidney outcomes in patients with type 2 diabetes.

Predictors of mortality of patients newly diagnosed with clinical type 2 diabetes: a 5-year follow up study.

BACKGROUND: At diabetes diagnosis major decisions about life-style changes and treatments are made based on characteristics measured shortly after diagnosis. The predictive value for mortality of these early characteristics is widely unknown. We examined the predictive value of patient characteristics measured shortly after diabetes diagnosis for 5-year all-cause and cardiovascular mortality with special reference to self-rated general health. METHODS: Data were from a population-based sample of 1,323 persons newly diagnosed with clinical diabetes and aged 40 years or over. Possible predictors of mortality were investigated in Cox regression models. RESULTS: Multivariately patients who rated their health less than excellent experienced increased all-cause and cardiovascular mortality. These end-points also increased with sedentary life-style, relatively young age at diagnosis and presence of cardiovascular disease (CVD) at diagnosis. Further predictors of all-cause mortality were male sex, low body mass index and cancer, while cardiovascular mortality increased with urinary albumin concentration. CONCLUSIONS: We found that patients who rated their health as less than excellent had increased 5-year mortality, similar to that of patients with prevalent CVD, even when biochemical, clinical and life-style variables were controlled for. This finding could motivate doctors to discuss perceptions of health with newly diagnosed diabetic patients and be attentive to patients with suboptimal health ratings. Our findings also confirm that life-style changes and optimizing treatment are particularly relevant for relatively young and inactive patients and those who already have CVD or (micro)albuminuria at the time of diabetes diagnosis.

Efficacy and safety of routine blood pressure lowering in older patients with diabetes: results from the ADVANCE trial.

OBJECTIVE: The efficacy and safety of blood pressure lowering in elderly patients have not been sufficiently investigated in patients with diabetes. Using data from the Action in Diabetes and Vascular disease: preterAx and diamicroN-MR Controlled Evaluation study, we assessed the efficacy and safety of routine blood pressure lowering to prevent major clinical outcomes in elderly patients with type 2 diabetes. METHODS: Eleven thousand one hundred and forty patients aged at least 55 years with type 2 diabetes (mean 66+/-6 years) were randomly assigned to perindopril-indapamide or placebo. The primary endpoint was a composite of major macrovascular and microvascular disease. The effects of active treatment on outcomes were estimated in subgroups according to age: below 65, 65-74 and at least 75 years. RESULTS: During a mean 4.3-year follow-up, 1799 (16.1%) patients experienced a major event. Active treatment produced similar relative risk reductions for the primary outcome, major macrovascular disease, death and renal events across age groups (all P heterogeneity >0.3). Over 5 years, active treatment was estimated to prevent one primary outcome in every 21, 71 and 118 patients of at least 75, 65-74 and below 65 years, respectively. Similar patterns of benefits were observed for secondary outcomes. There were no differences in the tolerability between randomized allocations across age groups (all P heterogeneity >0.6) CONCLUSION: Routine administration of perindopril-indapamide lowers blood pressure safely and reduces the risk of major clinical outcomes in patients of at least 75 years with type 2 diabetes. The greater absolute benefits in older patients in this age group were not offset by an increased risk of side effects.

Mistakes, misunderstandings and controversies in diabetes: A review and personal account.

A number of controversies in diabetes have had too little attention. I discuss the following issues: (i) drug therapy; (ii) genetics; (iii) antihypertensive treatment in patients with normoalbuminuria and with abnormal albuminuria; (iv) insulin analogs; (v) cancer in diabetes; (vi) hypophysectomy; (vii) renal biopsy; (viii) low protein diet; and (ix) glycated hemoglobin. A closer look at these items is required in order to have a more realistic picture of diabetes research. A scheme of other controversies is also provided. (J Diabetes Invest, doi: 10.1111/j.2040-1124.2010.00012.x, 2010).

[Microalbuminuria]. / Mikroalbuminuri.

Microalbuminuria is common in patients with hypertension and even lower levels of albuminuria reflect subclinical cardiovascular damage which is associated with increased cardiovascular risk. Reduction of albuminuria is associated with improved prognosis independently of reduction of blood pressure and regression of left ventricular hypertrophy. Accordingly, albuminuria--an integrated measure of cardiovascular risk--should be monitored and reduced through intensified antihypertensive treatment in combination with careful correction of other cardiovascular risk factors.

Microalbuminuria and short-term prognosis in patients undergoing cardiac surgery.

OBJECTIVES: To examine if preoperative microalbuminuria (MA) is associated with in increased risk of adverse outcomes in patients undergoing elective cardiothoracic surgery, and if adding information on MA could improve the accuracy of the additive EuroSCORE. METHODS: In a follow-up study we included 962 patients undergoing elective cardiothoracic surgery from 1 April 2005 to 30 September 2007 at our department. MA (urine albumin/creatinine ratio between 2.5-25 mg/mmol) was assessed in a morning spot-urine sample. We used population-based medical registries for 30-day follow-up and compared the length of stay and adverse outcomes including (i) all-cause death, myocardial infarction, stroke, or atrial fibrillation, (ii) surgical reintervention, renal insufficiency, sternal wound infection, or septicaemia among patients with and without MA. RESULTS: MA was found in 180 (18.7%) patients. The risk of both combined outcomes (adjusted odds ratios (ORs): 1.00 (95% confidence interval (CI): 0.77-1.30) and 1.18 (95% CI: 0.79-1.75), respectively) and most individual outcomes did not differ between the micro- and normoalbuminuric patients. The patients with MA and an additive EuroSCORE of 5 had a significantly prolonged median length of intensive care unit (ICU) stay (0.15 days [95% CI: 0.04-0.26]) and total hospital stay (0.5 days [95% CI: 0.04-0.96]). Patients with MA had a higher risk of postoperative septicaemia (OR: 12.1 [95% CI: 3.2-45.9]). Area under receiver operating characteristics curves of the EuroSCORE with regard to 30-day mortality was 0.86 both with and without MA. CONCLUSIONS: Preoperative MA in patients undergoing elective cardiothoracic surgery was not associated with most early adverse outcomes. However, risk of septicaemia was higher and patients with MA also had a marginally longer length of ICU and hospital stay. Information on preoperative MA did not improve the accuracy of the additive EuroSCORE.

Albuminuria and kidney function independently predict cardiovascular and renal outcomes in diabetes.

There are limited data regarding whether albuminuria and reduced estimated GFR (eGFR) are separate and independent risk factors for cardiovascular and renal events among individuals with type 2 diabetes. The Action in Diabetes and Vascular disease: preterAx and diamicroN-MR Controlled Evaluation (ADVANCE) study examined the effects of routine BP lowering on adverse outcomes in type 2 diabetes. We investigated the effects of urinary albumin-to-creatinine ratio (UACR) and eGFR on the risk for cardiovascular and renal events in 10,640 patients with available data. During an average 4.3-yr follow-up, 938 (8.8%) patients experienced a cardiovascular event and 107 (1.0%) experienced a renal event. The multivariable-adjusted hazard ratio for cardiovascular events was 2.48 (95% confidence interval 1.74 to 3.52) for every 10-fold increase in baseline UACR and 2.20 (95% confidence interval 1.09 to 4.43) for every halving of baseline eGFR, after adjustment for regression dilution. There was no evidence of interaction between the effects of higher UACR and lower eGFR. Patients with both UACR >300 mg/g and eGFR <60 ml/min per 1.73 m(2) at baseline had a 3.2-fold higher risk for cardiovascular events and a 22.2-fold higher risk for renal events, compared with patients with neither of these risk factors. In conclusion, high albuminuria and low eGFR are independent risk factors for cardiovascular and renal events among patients with type 2 diabetes.

Lowering blood pressure reduces renal events in type 2 diabetes.

BP is an important determinant of kidney disease among patients with diabetes. The recommended thresholds to initiate treatment to lower BP are 130/80 and 125/75 mmHg for people with diabetes and nephropathy, respectively. We sought to determine the effects of lowering BP below these currently recommended thresholds on renal outcomes among 11,140 patients who had type 2 diabetes and participated in the Action in Diabetes and Vascular disease: preterAx and diamicroN-MR Controlled Evaluation (ADVANCE) study. Patients were randomly assigned to fixed combination perindopril-indapamide or placebo, regardless of their BP at entry. During a mean follow-up of 4.3 yr, active treatment reduced the risk for renal events by 21% (P < 0.0001), which was driven by reduced risks for developing microalbuminuria and macroalbuminuria (both P < 0.003). Effects of active treatment were consistent across subgroups defined by baseline systolic or diastolic BP. Lower systolic BP levels during follow-up, even to <110 mmHg, was associated with progressively lower rates of renal events. In conclusion, BP-lowering treatment with perindopril-indapamide administered routinely to individuals with type 2 diabetes provides important renoprotection, even among those with initial BP <120/70 mmHg. We could not identify a BP threshold below which renal benefit is lost.

The management of the type 2 diabetic patient with hypertension - too late and too little: suggested improvements.

Patients with comorbid hypertension and type 2 diabetes are common, have a greatly increased risk of premature cardiovascular and renal morbidity and mortality, and are likely to increase substantially in number over the next 10-15 years. We suggest the need for more aggressive management strategies for these patients, regardless of their baseline blood pressure, including the early use of combination therapy with blockers of the renin-angiotensin system.

Twelve shifting paradigms in diabetic renal disease and hypertension.

In the last 30 years we have seen considerable progress in the management of patients with diabetes, in particular with diabetic renal disease. A number of paradigms have been broken down, namely the following, as a consequence, clinical care has improved dramatically. . Significant renal involvement and albuminuria is rare in patients with essential hypertension. 2. High GFR is good for prognosis. 3. Only proteinuric diabetic patients have a poor prognosis. 4. Microalbuminuria only predicts renal disease. 5. Reducing blood pressure may cause low perfusion in the kidney and other organs with long-term negative effect, especially on the glomerular filtration rate. 6. Only in the presence of high blood pressure, should microalbuminuric patients receive anti-hypertensive treatment, including blockade of the RAS. 7. Only reducing blood pressure by blocking RAS in diabetes is relevant and justified. 8. Normoalbuminuria as indicated in the present definition is 'normal'. 9. ACE-I or ARB can only be used separately. 10. Diastolic blood pressure and later systolic pulse pressure are the best parameters for blood pressure recording. 11. Microalbuminuria is the strongest risk marker in patients with type 1 diabetes. 12. Screening for microalbuminuria is relevant, but follow-up was not proposed (also regarding microalbuminuria). In the present situation, it is well-known that patients with essential hypertension may sometimes have microalbuminuria, and it is known that it predicts a poor prognosis. Interestingly, in type 1 diabetes, hyperfiltration is a marker for poor prognosis related to metabolic control. Thus hyperfiltration is a marker for bad development, but microalbuminuria (below the proteinuric level) is also associated with a poor prognosis. It was originally believed that microalbuminuria only predicts renal disease. However, surprisingly it predicts as well cardiovascular disease and early mortality. The story about blood pressure and progression of renal disease is interesting, because it was earlier believed that a certain high blood pressure was mandatory for preservation of the renal function. This appeared to be a completely wrong concept. The data regarding microalbuminuria suggest that patients with microalbuminuria should receive anti-hypertensive treatment, even patients with so-called normal blood pressure. This was confirmed in several trials and also included in the guidelines. Reducing blood pressure is important, but it appeared to be especially beneficial to block the renin-angiontensin system, and it is clear that albuminuria is a continuous variable and is also a risk factor. Earlier it was suggested to use ACE-inhibitors or ARBs. Now it is clear that it is possible to use a combination, with good theoretical background. In the history of hypertension, it was earlier believed that diastolic blood pressure was most important, but later on it was generally accepted that systolic is a better predictor and the goal for treatment and pulse pressure may be even better. Not only is microalbuminuria an important risk marker, but it is as well clear that regression of microalbuminuria is a good marker for a better prognosis in patients. Microalbuminuria is believed to be the strongest risk factor, but new studies actually suggest that a simple parameter such as self-rated health is crucial along with other factors. Regarding new developments, it is clear that new studies have led to several advancements in management in patients, for instance the Steno II study shows positive effect on mortality by multifactorial intervention. Similarly, the ADVANCE study also showed positive effect on mortality by more intensified anti-hypertensive treatment with an ACE-inhibitor. We are eagerly awaiting the results from glucose arm in the ADVANCE study, especially in the light of the ACCORD study showing increased mortality with too strict glycemic control with a goal of 6% in HbA1c.

Intensive blood glucose control and vascular outcomes in patients with type 2 diabetes.

BACKGROUND: In patients with type 2 diabetes, the effects of intensive glucose control on vascular outcomes remain uncertain. METHODS: We randomly assigned 11,140 patients with type 2 diabetes to undergo either standard glucose control or intensive glucose control, defined as the use of gliclazide (modified release) plus other drugs as required to achieve a glycated hemoglobin value of 6.5% or less. Primary end points were composites of major macrovascular events (death from cardiovascular causes, nonfatal myocardial infarction, or nonfatal stroke) and major microvascular events (new or worsening nephropathy or retinopathy), assessed both jointly and separately. RESULTS: After a median of 5 years of follow-up, the mean glycated hemoglobin level was lower in the intensive-control group (6.5%) than in the standard-control group (7.3%). Intensive control reduced the incidence of combined major macrovascular and microvascular events (18.1%, vs. 20.0% with standard control; hazard ratio, 0.90; 95% confidence interval [CI], 0.82 to 0.98; P=0.01), as well as that of major microvascular events (9.4% vs. 10.9%; hazard ratio, 0.86; 95% CI, 0.77 to 0.97; P=0.01), primarily because of a reduction in the incidence of nephropathy (4.1% vs. 5.2%; hazard ratio, 0.79; 95% CI, 0.66 to 0.93; P=0.006), with no significant effect on retinopathy (P=0.50). There were no significant effects of the type of glucose control on major macrovascular events (hazard ratio with intensive control, 0.94; 95% CI, 0.84 to 1.06; P=0.32), death from cardiovascular causes (hazard ratio with intensive control, 0.88; 95% CI, 0.74 to 1.04; P=0.12), or death from any cause (hazard ratio with intensive control, 0.93; 95% CI, 0.83 to 1.06; P=0.28). Severe hypoglycemia, although uncommon, was more common in the intensive-control group (2.7%, vs. 1.5% in the standard-control group; hazard ratio, 1.86; 95% CI, 1.42 to 2.40; P<0.001). CONCLUSIONS: A strategy of intensive glucose control, involving gliclazide (modified release) and other drugs as required, that lowered the glycated hemoglobin value to 6.5% yielded a 10% relative reduction in the combined outcome of major macrovascular and microvascular events, primarily as a consequence of a 21% relative reduction in nephropathy. (ClinicalTrials.gov number, NCT00145925.)

Endothelial perturbation: a link between non-dipping and retinopathy in type 2 diabetes?

Reduced diurnal blood pressure (BP) variation ("non-dipping") is associated with both micro- and macrovascular complications in patients with type 2 diabetes. The relation between endothelial perturbation and diurnal BP variation in diabetic subjects has not previously been studied. Seventy-six subjects, stratified to 4 gender-, age-, and duration-matched groups of 19 subjects each, were studied (group A: non-diabetic subjects; group B to D, type 2 diabetic subjects; group B: no retinopathy; group C: minimal background retinopathy; group D: diabetic maculopathy). All subjects underwent a 24-hour ambulatory BP monitoring. von Willebrand factor (vWF), fibrinogen, E-selectin, and intercellular adhesion molecule-1 were measured in plasma. Systolic night/day BP ratio increased gradually in groups A to D: 85.2 +/- 5%, 85.7 +/- 7%, 88.5 +/- 6%, and 90.5 +/- 7%, respectively, P < .05. Among diabetic patients, non-dippers had significantly higher plasma levels of vWF and fibrinogen than dippers (median/interquartile range 1.7/1.4 to 2.1 vs. 1.2/0.9 to 1.5 U/mL, P < .01 and 3.6/3.6 to 3.7 vs. 2.9/2.5 to 3.6 g/L, P = .01). Non-dipping is associated with elevated plasma levels of proteins related to endothelial cell activation as well as with retinopathy in subjects with type 2 diabetes. This finding suggests a possible mechanism linking non-dipping with microvascular complications in these subjects.

The blood pressure-induced diameter response of retinal arterioles decreases with increasing diabetic maculopathy.

BACKGROUND: The aim of the study was to compare the diameter response of retinal arterioles and retinal thickness in patients with different stages of diabetic maculopathy during an increase in the arterial blood pressure. METHODS: Four groups each consisting of 19 individuals were studied. Group A consisted of normal individuals and groups B-D consisted of type 2 diabetic patients matched for diabetes duration, age, and gender, and characterized by: Group B no retinopathy, Group C mild retinopathy, Group D maculopathy not requiring laser treatment. The diameter changes of a large retinal arteriole were measured using the Retinal Vessel Analyzer (RVA, Imedos, Germany) before, during, and after an increase in the blood pressure induced by isometric exercise. Additionally, the retinal thickness was measured using optical coherence tomography scanning. RESULTS: The arterioles contracted during isometric exercise in normal persons (diameter response: -0.70+/-0.48%) and in patients with no retinopathy (-1.15+/-0.44%), but dilated in patients with mild retinopathy (0.41+/-0.49%) and diabetic maculopathy (0.54+/-0.44%), p=0.01. Retinal thickness was normal in Group A (260+/-5.0 microm), Group B (257+/-4.5 microm), and Group C (253+/-4.4 microm), but was significantly (p=0.006) increased in Group D (279+/-5.3 microm). CONCLUSIONS: The diameter response was reduced in type 2 diabetic patients with retinopathy, whereas retinal thickness was increased in patients with diabetic maculopathy. This suggests that impairment of diameter response in retinal arterioles precedes the development of diabetic macular edema.

Urinary creatinine concentration is inversely related to glycaemic control and the presence of some diabetic complications in patients with newly diagnosed Type 2 diabetes.

BACKGROUND: The ratio between urinary albumin concentration (UAC) and urinary creatinine concentration (UCC) is widely used to estimate renal involvement. We examined how UAC and UCC associate with each other, with other risk factors, and with diabetic complications in a population-based sample of Type 2 diabetic patients. METHODS: A freshly voided morning urine specimen was provided by 1,284 consecutive, newly diagnosed diabetic patients aged 40 years or over in general practice. Albumin was measured by a polyethyleneglycol radioimmunoassay and creatinine by a modified Jaffe method. RESULTS: In a multivariate model including UAC, UCC, age, sex, HbA1c, and urinary glucose concentration, UAC increased with both age (P=.042) and HbA1c (P=.014), while UCC decreased (P<.001 and P<.001, respectively). In two regression models, the prevalence of diabetic retinopathy (P<.001) and relatively high resting heart rate (P<.001) increased with increasing UAC but decreased with increasing UCC (P=.002 and P=.005, respectively). CONCLUSION: The use of albumin/creatinine ratio (ACR) may introduce bias of unpredictable size and direction in comparisons of ACR with variables that are associated with UCC in their own right. In daily clinical practice, renal involvement in the individual patient can be estimated reliably with UAC or ACR measured in a freshly voided morning urine specimen, especially when considered together. However, the associations of the combined measure ACR should be interpreted with great caution in clinical and epidemiological research.