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H H Parving

Publications and source records attributed to H H Parving.

At least 73 records · Page 4Linked to original sources

Low-protein diet and kidney function in insulin-dependent diabetic patients with diabetic nephropathy.

BACKGROUND: Initiation of a low-protein diet (LPD) in patients with various nephropathies induces a faster initial and slower subsequent decline in the glomerular filtration rate (GFR). Whether this initial phenomenon is reversible or irreversible remains to be elucidated. METHODS: We performed an eight-week prospective, randomized, controlled study comparing the effect of an LPD with a normal-protein diet (NPD) in 29 insulin-dependent diabetic patients with diabetic nephropathy. At baseline, the patients were randomized to either an LPD (0.6 g.kg-1.24 hr-1, LPD group, N = 14) or their NPD (NPD group, N = 15) for four weeks (phase I). Between weeks 4 and 8, all patients received their NPD (phase II, recovery). Dietary protein intake (g.kg-1.24 hr-1), GFR (51Cr-EDTA, ml.min-1.1.73 m-2), albuminuria (enzyme-linked immunoadsorbent assay, mg.24 hr-1), and arterial blood pressure (Hawksley random zero sphygmomanometer, mm Hg) were measured at baseline and after four- and eight-weeks of follow-up. During the investigation, all patients in the LPD group (N = 12) and in the NPD group (N = 14) received their usual antihypertensive treatment. RESULTS: At baseline, the LPD group and the NPD group were comparable regarding dietary protein intake, GFR, albuminuria, and arterial blood pressure. During phase I, a significant decline in dietary protein intake, GFR, and albuminuria (mean, 95% CI) was observed in the LPD group [0.4 (0.3 to 0.5) g.kg-1.24 hr-1, 8.6 (3.2 to 13.9) ml.min-1.1.73 m-2, and 28.7 (14.0 to 40.9)%, respectively] compared with the NPD group [0.0 (-0.1 to 0.2) g.kg-1.24 hr-1 (P < 0.0001 between diets), 2.5 (-1.8 to 6.8) ml.min-1.1.73 m-2 (P = 0.07 between diets), and 0.0 (-20.1 to 23.5)% (P < 0.05 between diets), respectively]. Conversely, during phase II, a significant increase in dietary protein intake, GFR, and albuminuria [mean, 95% CI; 0.3 (0.2 to 0.5) g.kg-1.24 hr-1, 5.9 (0.8 to 11.1) ml.min-1.1.73 m-2, and 25.0 (4.5 to 49.6)%, respectively] took place in the LPD group compared with the NPD group [0.0 (-0.2 to 0.1) g.kg-1.24 hr-1 (P < 0.0001 between diets), -2.9 (-6.4 to 0.6) ml.min-1.1.73 m-2 (P < 0.01 between diets), and 2.9 (-18.3 to 29.7)% (P = 0.16 between diets), respectively]. Arterial blood pressure was comparable in the two groups of patients during phase I and II. CONCLUSIONS: Dietary protein restriction for four weeks induces a reversible decline in GFR and albuminuria in insulin-dependent diabetic patients with diabetic nephropathy, whereas systemic blood pressure remains unchanged.

Adult↗

Impaired autoregulation of the glomerular filtration rate in patients with nondiabetic nephropathies.

BACKGROUND: The ability of the kidney to maintain constancy of the glomerular filtration rate (GFR) over a wide range of renal perfusion pressures is termed autoregulation. Defective autoregulation of GFR has been demonstrated in diabetic nephropathy. Whether this is also the case in patients with nondiabetic nephropathies is not known. METHODS: We investigated the effect of acute lowering of blood pressure (BP) on GFR in 16 (8 males and 8 females) albuminuric subjects suffering from different nondiabetic nephropathies and in 14 (7 males and 7 females) controls matched with respect to sex, age, BP, and baseline GFR. The subjects received in random order an intravenous injection of either clonidine (150 to 225 microg) or saline (0.154 mmol/liter) within two weeks. We measured GFR ([51Cr]-EDTA), albuminuria (enzyme-linked immunosorbent assay; ELISA), and BP (Takeda TM-2420). RESULTS: Clonidine induced similar reductions in mean arterial BP 17 (2) versus 19 (2) mm Hg [mean (SE)] in patients with nephropathy and in controls, respectively. GFR diminished in average from 89 (6) to 82 (5) ml/min/1.73 m2 (P < 0.05), and albuminuria declined from a geometric mean of 1218 (antilog SE 1.3) microg/min to 925 (1.3) in the patients with nondiabetic nephropathies (P < 0.05), whereas these variables remained unchanged in the control group. The mean difference between changes in GFR (95% confidence interval) between the nondiabetic macroalbuminuric and control subjects was 6.1 (-0.03 to 12.21) ml/min/1.73 m2 (P = 0.051). CONCLUSION: Our study suggests that albuminuric patients with nondiabetic nephropathies frequently suffer from impaired autoregulation of GFR.

Adolescent↗

Progression of diabetic nephropathy in normotensive type 1 diabetic patients.

BACKGROUND: The first aim of our long-term study was to describe the natural history of diabetic nephropathy in 59 normotensive type 1 diabetic patients. Secondly, we evaluated genetic and nongenetic progression promoters. METHODS: The following progression promoters were determined: the insertion/deletion polymorphism in the angiotensin converting enzyme (ACE) gene, blood pressure, albuminuria, hemoglobin A1c, cholesterol, smoking, height, and gender. We studied the natural history by measuring 51Cr-EDTA plasma clearance at yearly intervals at least three times during [median (range)] 5.5 (2.2 to 18.3) years. RESULTS: At baseline the three groups (II, N = 11; ID, N = 25, and DD, N = 23) had comparable GFR (103 +/- 16; 99 +/- 19; 113 +/- 22 ml/min/1.73 m2, respectively; mean +/- SD), arterial blood pressure, albuminuria, and hemoglobin A1c. During the follow-up there was a median rate of decline in GFR in all 59 patients of 1.2 (range 12.9 to -4.4) ml/min/year. During the study period no significant differences were observed in: the rate of decline in glomerular filtration rate [median (range) 0.9 (10.6 to -1.9); 2.5 (12.9 to -4.4); 1.4 (10.8 to -1.9 ml/min/year)], arterial blood pressure, albuminuria, hemoglobin A1c or cholesterol between the three groups (II, ID and DD), respectively. At baseline, multiple linear regression analysis including the above-mentioned putative risk factors revealed that albuminuria, short stature, and male gender independently predict an enhanced decline in GFR [R2 (adjusted) = 0.33; P < 0.002]. During the follow-up period, only albuminuria acted as an independent progression promoter [R2 (adjusted) = 0.37; P < 0.0001]. CONCLUSIONS: Our study revealed a rather slow progression of kidney disease in normotensive type 1 diabetic patients with diabetic nephropathy. Albuminuria, short stature, and male gender act as progression promoters in such patients.

Adult↗

The Trp64Arg amino acid polymorphism of the beta3-adrenergic receptor gene does not contribute to the genetic susceptibility of diabetic microvascular complications in Caucasian type 1 diabetic patients.

OBJECTIVE: The beta3-adrenergic receptor is involved in regulation of microvascular blood flow. A missense mutation (Trp64Arg) in the beta3-adrenergic receptor gene has been suggested as a risk factor for proliferative retinopathy in Japanese type 2 diabetic patients. The aim of the present study was to evaluate the contribution of this polymorphism to the development of microangiopathic complications in Caucasian type 1 diabetic patients. SUBJECTS AND METHODS: We studied the relationship between the Trp64Arg polymorphism in type 1 diabetic patients with nephropathy (204 men/132 women, age 42.8 +/- 11.0 years, diabetes duration 28 +/- 9 years) and in type 1 diabetic patients with persistent normoalbuminuria (118 men/73 women, age 42.6 +/- 10.2 years, diabetes duration 27 +/- 8 years). Proliferative retinopathy was present in 254 patients (48%), while 66 patients (13%) had no diabetic retinopathy. RESULTS: There were no differences in Trp64Arg genotype distribution between type 1 diabetic patients with diabetic nephropathy and type 1 diabetic patients with normoalbuminuria: 295 (88%)/38 (11%)/3 (1%) vs 161 (84%)/30 (16%)/- had Trp/Trp, Trp/Arg or Arg/Arg genotype respectively. Odds ratio (95% CI) of nephropathy in carriers of the mutation was 0.75 (0.45-1.25). No associations between the Trp64Arg polymorphism and simplex or proliferative retinopathy were revealed either. The frequency of the Arg-allele was 0.069 in patients with proliferative retinopathy, 0.066 in patients with simplex retinopathy and 0.090 in patients with no signs of diabetic retinopathy, NS. CONCLUSIONS: The Trp64Arg polymorphism of the beta3-adrenergic receptor gene does not contribute to the genetic susceptibility to diabetic nephropathy in Caucasian type 1 diabetic patients. Nor does our study support previous findings of an association between this variant and proliferative retinopathy.

Adult↗

Plasma renin and prorenin and renin gene variation in patients with insulin-dependent diabetes mellitus and nephropathy.

BACKGROUND: The most striking abnormality in the renin angiotensin system in diabetic nephropathy (DN) is increased plasma prorenin. Renin is thought to be low or normal in DN. In spite of altered (pro)renin regulation the renin gene has not been studied for contribution to the development of DN. METHODS: We studied plasma renin, prorenin, and four polymorphic markers of the renin gene in 199 patients with IDDM and DN, and in 192 normoalbuminuric IDDM controls matched for age, sex, and duration of diabetes. Plasma renin and total renin were measured by immunoradiometric assays. Genotyping was PCR-based. RESULTS: Plasma renin was increased in patients with nephropathy (median (range), 26.3 (5.2-243.3) vs 18.3 (4.2-373.5) microU/ml in the normoalbuminuric group, P<0.0001). Prorenin levels were elevated out of proportion to renin levels in nephropathic patients (789 (88-5481) vs 302 (36-2226) microU/ml, P<0.0001). Proliferative retinopathy had an additive effect on plasma prorenin, but not on renin. DN was associated with a BglI RFLP in the first intron of the renin gene (bb-genotype: n=106 vs 82 in DN and normoalbuminuric patients respectively, P=0.037), but not with three other polymorphisms in the renin gene. A trend for association of higher prorenin levels with the DN-associated allele of this renin polymorphism was observed in a subgroup of patients with DN (bb vs Bb+BB, P=0.07). CONCLUSIONS: The results indicate that in DN there is an increase in both renin and prorenin levels. A renin gene polymorphism may contribute weakly to DN. Although speculative, one of the renin gene alleles could lead to increased renin gene expression, leading to higher renin and prorenin levels. These may play a role in the pathogenesis of DN.

Adult↗

Amadori albumin in type 1 diabetic patients: correlation with markers of endothelial function, association with diabetic nephropathy, and localization in retinal capillaries.

Nonenzymatic glycation is increased in diabetes. Most studies so far have focused on the role of advanced glycation end products (AGEs) in vascular complications, whereas the role of early glycation Amadori-modified proteins, which is the predominant form of glycated proteins, has not been systemically investigated in humans. We developed an antiserum against glycated human serum albumin (HSA) and used this to study the role of early glycation products in vascular complications in type 1 diabetic patients. Amadori albumin was determined to be the recognition epitope of the antiserum. The antibody recognized a specific glucose adduct and a conformational component specific for human albumin in Amadori albumin, with no recognition of AGEs. Plasma Amadori albumin levels were significantly higher in type 1 diabetic patients (n = 55) than in healthy control subjects (n = 60) (39.2+/-9.9 vs. 20.9+/-4.0 U/ml, P < 0.0005). Amadori albumin correlated with levels of plasma markers of endothelial function von Willebrand factor (r = 0.29, P < 0.05) and vascular cell adhesion molecule-1 (r = 0.41, P < 0.005), but not soluble E-selectin. In addition, Amadori albumin immunoreactivity was detected in the capillaries of retinas of diabetic patients. Plasma levels of Amadori albumin were determined in a second group of type 1 diabetic patients with long-standing diabetes with (n = 199) or without (n = 192) diabetic nephropathy. Patients with nephropathy had higher Amadori albumin levels than did those without it (50.9+/-9.5 vs. 45.1+/-6.3 U/ml, P < 0.0005). Age-, sex-, and diabetes duration-adjusted analyses showed that nephropathy was significantly associated with Amadori albumin with an odds ratio (OR [95% CI]) of 1.11 [1.08-1.15] per U/ml increase. After additional adjustment for levels of creatinine, glycated hemoglobin, cholesterol, triglycerides, blood pressure, preexistent retinopathy, and cardiovascular disease, Amadori albumin continued to be significantly associated with nephropathy (OR 1.06 [1.01-1.11]) per U/ml increase. Our results are consistent with a proposed pathophysiological role of Amadori albumin in microvascular complications of type 1 diabetic patients.

Adult↗

Cyclosporine nephrotoxicity in type 1 diabetic patients. A 7-year follow-up study.

OBJECTIVE: To evaluate kidney function 7 years after the end of treatment with cyclosporine A (CsA) (initial dosage of 9.3 tapered off to 7.0 mg.kg-1.day-1) in young patients (mean age 20 years) with newly diagnosed type 1 diabetes participating in a randomized, double-blind, placebo-controlled CsA trial. RESEARCH DESIGN AND METHODS: In this study, 21 patients received CsA for 12.5 +/- 4.0 months (mean +/- SD) and 19 patients received placebo for 14.4 +/- 3.8 months. The two groups were similar with regard to mean arterial blood pressure (BP), urinary albumin excretion rate (UAER), serum creatinine, and estimated glomerular filtration rate (GFR [Cockcroft and Gault]) at initiation of CsA treatment (baseline). HbA1c (mean +/- SEM) during 7 years of follow-up was also the same: 8.7 +/- 0.4 vs. 8.3 +/- 0.4% in the CsA and placebo groups, respectively. RESULTS: During the 7 years after cessation of study medication, two CsA group patients and one control patient were lost to follow-up. One placebo-treated patient developed IgA nephropathy (biopsy proven) and was excluded. Four CsA-treated patients developed persistently elevated UAER > 30 mg/24 h (n = 3 with microalbuminuria), whereas all the 17 placebo-treated patients had normal UAER (< 30 mg/24 h) after 7 years of follow-up. At the end of follow-up, the CsA group had a more pronounced rise in UAER: 2.5-fold (95% CI 1.4-4.5) higher than baseline value vs. 1.1-fold (0.7-1.7) in the placebo-treated group (P < 0.05). Estimated GFR (ml.min-1.1.73 m-2) declined from baseline to end of follow-up (1994) by 6.3 +/- 6.0 in the former CsA group, whereas it rose by 7.4 +/- 5.0 in the placebo group (P = 0.05). In 1994, 24-h blood pressure was nearly the same: 131/77 +/- 4/2 vs. 127/75 +/- 2/2 mmHg (NS) in the CsA and placebo groups, respectively. Five randomly selected CsA-treated patients had a kidney biopsy performed shortly after the CsA treatment was stopped. Interstitial fibrosis/tubular atrophy and/or arteriolopathy were present in two subjects who both subsequently developed persistent microalbuminuria. CONCLUSIONS: The results of our 7-year follow-up study suggested that short-lasting CsA treatment in young, newly diagnosed type 1 diabetic patients accelerated the rate of progression in UAER and tended to induce a loss in kidney function. Longer term follow-up is mandatory to clarify whether CsA-treated patients are at increased risk of developing clinical nephropathy.

Adult↗

Effects of nisoldipine and lisinopril on left ventricular mass and function in diabetic nephropathy.

OBJECTIVE: To compare the effects of the calcium channel blocker, nisoldipine, and the ACE inhibitor, lisinopril, on left ventricular mass (LVM) and systolic function in type 1 diabetic patients with diabetic nephropathy. RESEARCH DESIGN AND METHODS: M-mode echocardiography was performed in 50 hypertensive type 1 diabetic patients with diabetic nephropathy enrolled in a 1-year, randomized, double-blind, parallel study of antihypertensive treatment with nisoldipine CC (20-40 mg/day) or lisinopril (10-20 mg/day). Ambulatory 24-h blood pressure was measured with the Takeda TM 2420 device (A & D, Tokyo, Japan) every 3 months. Three patients dropped out and seven patients were excluded due to technical difficulties. RESULTS: The 24-h diastolic blood pressure was reduced from 83 to 80 mmHg in the nisoldipine group (P = 0.06) and from 85 to 80 mmHg in the lisinopril group (P = 0.02). The decline in systolic blood pressure was not significant with any of the two treatments, and no difference in reduction of blood pressure was seen between groups. LVM corrected for body surface area (LVMI) was comparable between groups at baseline and increased from 96 +/- 5 to 107 +/- 6 g/m2 (mean +/- SEM; P = 0.007) in the nisoldipine group and from 95 +/- 4 to 103 +/- 5 g/m2 (P = 0.03) in the lisinopril group. The mean difference between the change in LVMI in the two groups was 2.9 (95% CI 6.8 to 12.7) g/m2. The prevalence of left ventricular hypertrophy rose from 18 (95% CI 6-30) to 30% (16-44) during the study period. A multiple linear regression analysis revealed that after 1 year of treatment, LVMI increased with higher systolic blood pressure level and declining glomerular filtration rate (R2 = 0.25). Fractional shortening was within normal range at baseline, 42 +/- 1 vs. 41 +/- 1% with nisoldipine and lisinopril, respectively, and did not change during follow-up. CONCLUSIONS: Antihypertensive treatment with nisoldipine or lisinopril to bring diastolic blood pressure level within the normal target range does not hinder a rise in LVMI in type 1 diabetic patients with diabetic nephropathy.

Adult↗

Diabetic hypertensive patients. Is this a group in need of particular care and attention?

Morbidity and mortality in diabetes are caused mainly by its vascular complications, both in the microcirculation and in the large vessels. Diabetic nephropathy and retinopathy are the clinical hallmarks of microangiopathy, which may lead to end-stage renal failure and blindness. The cardiovascular complications in diabetes consist mainly of an accelerated form of atherosclerosis. Systemic hypertension is an early and frequent phenomenon. Nocturnal hypertension is also more frequent in people with diabetes compared with the nondiabetic population. Capillary hypertension has been demonstrated in type 1 diabetic patients. Poor metabolic control may induce elevation in blood pressure, but data are conflicting. The prevalence of white-coat hypertension in the diabetic population is comparable with that in the nondiabetic population. Prospective observational studies in type 1 and type 2 patients have revealed that abnormally increased urinary albumin excretion and other potentially modifiable risk factors--such as hypertension, smoking, poor metabolic control, and social class--predict increased all-cause mortality and cardiovascular mortality. Arterial hypertension is a risk factor in the initiation and progression of diabetic micro- and macroangiopathy. Diabetes, hypertension, and smoking are the three most important risk factors for fatal and nonfatal stroke. A randomized, double-blind, parallel study has revealed that the 5-year major cardiovascular disease rate was lowered by 34% for antihypertensive treatment compared with placebo. Furthermore, the study found a trend for lower all-cause mortality for low-dose antihypertensive-treated diabetic patients. Effective blood pressure reduction with ACE inhibitors and/or non-ACE inhibitors, frequently in combination with diuretics, reduces albuminuria, delays the progression of nephropathy, postpones end-stage renal failure, and improves survival in diabetic nephropathy.

Albuminuria↗

Calcium antagonists and cardiovascular risk in diabetes.

Recent trials have linked calcium antagonists with adverse cardiovascular events in hypertensive patients with diabetes. A closer examination of these trials (in particular the Appropriate Blood Pressure Control in Diabetes [ABCD] trial and the Fosinopril Versus Amlodipine Cardiovascular Events Trial [FACET]) reveals a lack of data from which to draw conclusions of harm. In fact, based on the results of these trials and the recent Hypertension Optimal Treatment (HOT) Trial, one may conclude that the combination of a calcium antagonist with an ACE inhibitor is a rational therapeutic choice in patients with coexisting hypertension and diabetes.

Amlodipine↗

[The significance of deletion polymorphism in the ACE gene for progression of diabetic nephropathies treated with ACE inhibitors].

The aim of the study was to evaluate the effect of an insertion/deletion polymorphism of the angiotensin converting enzyme (ACE) gene on progression of diabetic nephropathy. We performed an observational follow-up study of 35 patients with insulin-dependent diabetes and diabetic nephropathy. Patients were investigated during captopril treatment for a median of seven (range three to nine) years. Eleven patients were homozygous for the deletion allele (DD) and 24 were hetero- or homozygous for the insertion allele (ID + II). The two groups had comparable glomerular filtration rate, albuminuria and blood pressure at baseline and captopril induced nearly the same mean reduction in blood pressure--to 103 (SD 5) mm Hg in the DD-group and 102 (8) mm Hg in the ID + II-group. The rate of decline in glomerular filtration rate was significantly steeper in the DD group than in the other group (mean 5.7 (SD 3.7) versus 2.6 (2.8) ml/min/year, p = 0.01). In conclusion, the deletion polymorphism in the ACE gene reduces the long term beneficial effect of ACE inhibition on the progression of diabetic nephropathy in patients with insulin dependent diabetes.

Adult↗

[Significant risk factors for development of microalbuminuria and diabetic nephropathy in patients with non-insulin-dependent diabetes].

Putative risk factors for the development of incipient diabetic nephropathy (persistent microalbuminuria) and overt diabetic nephropathy (persistent macroalbuminuria) were evaluated prospectively in Caucasian non-insulin dependent diabetic (NIDDM) patients. All NIDDM patients < 66 years, with normoalbuminuria (albumin excretion rate [AER] < 30 mg/24 h), attending our clinic during 1987 were identified (n = 191). The patients were followed for a median of 5.8 years. Fifteen of the 191 patients were lost to follow-up. Thirty-six of the remaining 176 patients developed persistent microalbuminuria (AER 30-299 mg/24 h) and five developed persistent macroalbuminuria (AER less than or equal to 300 mg/24 h) during follow-up. The five-year cumulative incidence of incipient diabetic nephropathy was 23% (95% confidence interval 17% to 30%). Baseline log10 AER, male gender, presence of retinopathy, S-cholesterol, HbA1c, and age was found to predict the development of incipient/overt diabetic nephropathy in these patients.

Adult↗

[Risk factors for mortality in patients with insulin-dependent diabetes].

The prognostic significance of microalbuminuria, macroalbuminuria and other putative risk factors for mortality in insulin-dependent diabetic patients were evaluated in a 10 year prospective study. We identified 939 insulin-dependent diabetic patients; 593 patients had normoalbuminuria (< or = 30 mg/24 h), 181 had microalbuminuria (31-299 mg/24 h), and 165 had macroalbuminuria (> or = 300 mg/24 h). Fifteen percent of patients with normoalbuminuria, 25% with microalbuminuria and 44% with macroalbuminuria at baseline died during follow-up (p < or = 0.01). Significant predictors of all-cause mortality were male sex, age, height, smoking, low social class, urinary albumin excretion, hypertension, serum creatinine, and HbA1c. Age, smoking, microalbuminuria, overt nephropathy, and hypertension were significant predictors of cardiovascular mortality. The mortality in patients with microalbuminuria was only slightly increased compared to patients with normoalbuminuria. Median survival after onset of overt diabetic nephropathy was 13.9 (11.8 to 17.2) years. Abnormally elevated urinary albumin excretion and other potentially modifiable risk factors such as hypertension, smoking, poor glycaemic control and social class predicts increased mortality in insulin-dependent diabetic patients.

Adult↗

Is antihypertensive treatment the same for NIDDM and IDDM patients?

The prevalence of abnormally elevated albumin excretion rate (> 30 mg/24 h) is approximately 40% in insulin-dependent (IDDM) and non-insulin-dependent (NIDDM) diabetic patients. Diabetes has become the leading cause of end-stage renal failure in the US, Japan and Europe. Approximately 90% of the direct and indirect cost of caring for diabetic patients are spent on the complications of diabetes. Identification of patients at high risk of developing diabetic nephropathy is possible by screening for microalbuminuria (30-300 mg/24 h). Elevated urinary albumin excretion rate indicates a substantially increased mortality risk in diabetic patients. Randomised controlled trials in normotensive IDDM and NIDDM patients with persistent microalbuminuria indicate that ACE inhibitors diminish urinary albumin excretion rate, postpone it and may even prevent progression to clinical overt nephropathy. These findings indicate that screening and intervention programs are likely to have life saving effects and lead to considerable economic savings. Systemic blood pressure elevation to a hypertensive level is an early and frequent phenomenon in diabetic nephropathy. Furthermore, nocturnal blood pressure elevation (non-dippers) occurs more frequently in patients with nephropathy. Systemic blood pressure elevation and to a lesser degree albuminuria accelerate the progression of diabetic nephropathy. Effective blood pressure reduction with non-ACE-inhibitors and/or ACE-inhibitors frequently in combination with diuretics: (a) reduces albuminuria; (b) delays the progression of nephropathy; (c) postpones renal insufficiency; and (d) improves survival in IDDM and NIDDM patients with diabetic nephropathy. A specific renal protective effect of ACE-inhibitors in diabetic nephropathy has been demonstrated in IDDM patients with moderately reduced kidney function (s-creatinine > 133 mumol/l) while the data conflict with NIDDM patients. Antihypertensive treatment for diabetic nephropathy simultaneously extends life and saves money. Finally, reduced risk of fatal and non-fatal cardiovascular events have been demonstrated when diabetic patients with isolated systolic hypertension are treated with blood pressure lowering agents. Absolute risk reduction with active treatment compared to placebo was twice as great for the diabetic versus non-diabetic patients (101/1000 versus 51/1000 randomised participants at the 5-year follow-up), reflecting the higher risk of diabetic patients. In conclusion, early detection and aggressive treatment of arterial hypertension with ACE-inhibitors, long acting calcium antagonist and low dose diuretics as first line drugs are highly warranted in diabetic patients with or without diabetic renal disease.

Albuminuria↗

Assessment of glomerular filtration rate in diabetic nephropathy using the plasma clearance of 51Cr-EDTA.

Plasma clearance of 51Cr-EDTA is widely used to assess the glomerular filtration rate (GFR) in diabetic nephropathy. Originally, the ratio between the intravenously injected amount of tracer and the total area under the plasma concentration curve was used for the calculation of total 51Cr-EDTA plasma clearance (C(T)). Simplified methods, using the final mono-exponential part of the plasma curve, have been suggested, e.g. four samples, taken 180 to 240 min after injection (C(IV)), or using one sample taken at 240 min (C(I)). Our aim was to evaluate the agreement between measurements of GFR and rate of decline in GFR based upon these three methods. Bland & Altman plots were used to illustrate the range of agreement. We investigated 76 insulin-dependent diabetic (IDDM) patients with microalbuminuria or diabetic nephropathy. GFR was measured after a single intravenous injection of 3.7 MBq 51Cr-EDTA by determining the radioactivity in venous blood samples taken 5, 7, 10, 15, 30, 45, 60, 90, 120, 150, 180, 200, 220, and 240 min after the injection. Rate of decline in GFR was assessed using 12 (6-17) determinations of GFR over a period of time of 8 (4-10) years. Mean (SD) GFRT was 123 (21) ml x min(-1) compared to GFR(IV) 123 (21) ml x min(-1) (NS) and GFR(I) 115 (17) ml x min(-1) (p < 0.00001). The mean difference (95% limits of agreement) between GFR(T) and GFR(IV) was +0.6 (-16.6 to +17.7) ml x min(-1), and between GFR(T) and GFR(I) +8.0 (-6.0 to +22.2) ml x min(-1). The difference between GFR(T) and GFR(I) was significantly correlated with their mean value (r = 0.56, p < 0.00001), indicating increasing underestimation by GFR(I) with increasing GFR levels. The mean (SD) rate of decline in GFR(T) was 2.3 (3.9) ml x min(-1) x year(-1), compared to a mean rate of decline in GFR(IV) of 2.4 (3.6) ml x min(-1) x year(-1) (NS), and a mean rate of decline in GFR(I) of 2.2 (3.5) ml x min(-1) x year(-1) (NS). The mean difference (95% limits of agreement) between rate of decline in GFR(T) and rate of decline in GFR(IV) was +0.16 (-1.59 to +1.91) ml x min(-1) x year(-1), and between rate of decline in GFR(T) and rate of decline in GFR(I) -0.01 (-1.64 to +1.61) ml x min(-1) x year(-1), respectively. In conclusion, our cross-sectional study revealed a close agreement between GFR(T) and GFR(IV) with acceptable limits of agreement (precision), while GFR(I) lacked accuracy. However, a close agreement between rate of decline in GFR(T) and rate of decline in GFR(IV), and between rate of decline in GFR(T) and rate of decline in GFR(I), with acceptable limits of agreement (precision), suggests that both simplified methods are applicable for long-term follow-up.

Chromium Radioisotopes↗