Predictors of angiotensin-converting enzyme inhibitor-induced reduction of urinary albumin excretion in nondiabetic patients

Urinary albumin excretion is a predictor for cardiovascular mortality and morbidity. We investigated which parameters determine baseline urinary albumin excretion in nondiabetic subjects, without renal disease. In addition, we evaluated the parameters that predict the albuminuria-lowering efficacy of an angiotensin-converting enzyme inhibitor. In this substudy of the Prevention of Renal and Vascular Endstage Disease Intervention Trial, 384 microalbuminuric patients were included. Patient and biochemical characteristics were obtained at baseline and after 3 months of double-blinded, randomized treatment (fosinopril 20 mg or placebo). Mean age was 51.1+/-11.5 years, and 65.6% were male. Median urinary albumin excretion was 22.2 mg per 24 hours. At baseline, mean arterial pressure (beta(standardized)=0.161; P=0.006), urinary sodium excretion (beta(standardized)=0.154; P=0.011), and estimated renal function were independently associated with albumin excretion. In these predominantly normotensive to prehypertensive subjects, fosinopril reduced albumin excretion by 18.5% versus a 6.1% increase on placebo after 3 months (P<0.001). Fosinopril use and blood pressure reduction independently predicted the change in urinary albumin excretion. Baseline urinary albumin excretion independently predicted the antialbuminuric effect of fosinopril (beta(standardized)=-0.303; P<0.001). In conclusion, at baseline, sodium intake and blood pressure were positively associated with urinary albumin excretion. Fosinopril reduced albuminuria more than might be expected from its blood pressure-lowering effect alone, and this effect was more outspoken in subjects with higher baseline albumin excretion. Based on our data, we hypothesize that angiotensin-converting enzyme inhibition may result in superior cardiovascular protection when compared with other blood pressure-lowering agents in subjects with higher baseline levels of albuminuria.     

Elevated urinary prostaglandin excretion and the effect of indomethacin on renal function in incipient diabetic nephropathy

We investigated whether the glomerular synthesis of prostaglandins modulates the glomerular filtration rate and urinary albumin excretion in incipient diabetic nephropathy (defined as urinary albumin excretion between 30 and 300 mg/24 h (microalbuminuria) in two out of three sterile ketone-free 24-h urine collections in patients having insulin-dependent diabetes mellitus (IDDM) without hypertension or other kidney disease). The urinary excretion of prostaglandin E2 was significantly elevated in 8 insulin-dependent diabetic patients with incipient nephropathy as compared with 9 normoalbuminuric IDDM patients and 11 healthy controls: 317 (182-1273); 95 (67-225); 132 (54-263) pg/min, respectively (2p less than 0.01). Glomerular filtration rate (single bolus 51Cr-EDTA technique) and albuminuria (radioimmunoassay) were measured twice within 2 weeks in 8 females having IDDM with incipient nephropathy. The study design was a randomized double-blind trial with the patients receiving either indomethacin (150 mg/day) or placebo for 3 days prior to the kidney function studies. Indomethacin treatment induced a significant reduction in urinary prostaglandin E2 excretion (73%) (2p less than 0.01), urinary albumin excretion rate diminished from 207 (63-253) to 87 (49-147) mg/24 h (2p less than 0.01), fractional clearance of albumin declined (70%) (2p less than 0.01). Glomerular filtration rate remained stable (108 (88-133) versus 110 (95-142) ml/min). Blood glucose and blood pressure were comparable during the placebo and indomethacin treatment (12.6 +/- 3 versus 13.4 +/- 5 mmol/l and 122/79 +/- 3/9 versus 122/82 +/- 4/10 mmHg, respectively). Our results suggest that enhanced glomerular synthesis of vasodilating prostaglandins may accelerate microalbuminuria in incipient diabetic nephropathy.     

Effect of zinc supplementation on microalbuminuria in patients with type 2 diabetes: a double blind, randomized, placebo-controlled, cross-over trial

OBJECTIVES: Oxidative stress can contribute to microvascular complications in diabetes. A decisive event associated with this condition may be the decrease in the synthesis of zinc-containing antioxidant enzymes such as superoxide dismutase and glutathione peroxidase. This consideration led us to investigate the effect of zinc supplementation versus placebo on microalbuminuria in diabetic patients in a randomized double blind clinical trial. METHODS: Fifty diabetic patients with microalbuminuria were enrolled. Fasting plasma glucose, HbA1c, lipid profiles, plasma zinc levels and random urine for albumin and creatinine were measured. Patients randomly received 30 mg elemental zinc (group 1) or placebo (group 2) for 3 months. After a 4 week wash-out period, the groups were crossed over (i.e. the zinc group were given placebo, and the placebo group were given zinc) and the protocol was repeated. RESULTS: From an initial number of 50 selected patients (25 in each of two groups), 39 patients (21 in group 1 and 18 in group 2) completed the study. In group 1, after zinc supplementation, urinary albumin excretion decreased significantly from 86.5 ± 57 to 75 ± 71 mg/g (p = 0.01). After placebo, patients in group 1 showed no significant reduction in microalbuminuria (85 ± 72 mg/g to 83 ± 63 mg/g creatinine). In group 2, no change in albumin excretion was observed after placebo treatment (90.5 ± 63 mg/g to 90 ± 60 mg/g creatinine). After zinc supplementation, a significant reduction was observed in albumin excretion, from 90 ± 60 mg/g to 85 ± 57 mg/g creatinine (p = 0.003). CONCLUSIONS: Zinc supplementation reduced albumin excretion in microalbuminuric type 2 diabetic patients. This outcome may be due to the antioxidant effect of zinc.     

Effect of volume expansion on hemodynamics, capillary permeability and renal function in conscious, cirrhotic rats

General and splanchnic hemodynamics (radioactive microspheres), renal function, spontaneous and histamine-mediated vasopermeability and albumin distribution space were studied in conscious control and nonascitic cirrhotic rats, before and after a moderate and sustained saline infusion (3% of body weight per 30 min + repletion of urinary losses). In basal conditions, cirrhotic rats showed lower fractional sodium excretion than did control rats (0.09 +/- 0.01 vs. 0.15 +/- 0.01%, p less than 0.005). In addition, cirrhotic animals showed higher cardiac output (161.4 +/- 12.8 ml per min) and lower total peripheral resistance (0.63 +/- 0.05 mm Hg . min per ml) and mean arterial pressure (102.9 +/- 3.9 mm Hg) than did control rats (cardiac output: 89.0 +/- 7.6; total peripheral resistance: 1.31 +/- 0.11; mean arterial pressure: 117.5 +/- 5.11; p less than 0.005). No differences in portal-systemic shunt rate or vasopermeability between both groups were observed. After saline infusion, fractional sodium excretion increased to 4.31 +/- 0.16% in controls but only 2.11 +/- 0.02% in cirrhotic animals. In this group, cardiac output decreased by 49.6 +/- 5.1% whereas mean arterial pressure and total peripheral resistance increased by 7.1 +/- 0.6 and 112 +/- 10%, respectively. In control rats, no significant hemodynamic changes were observed. Blood gases did not change after expansion in any group. Saline infusion induced an increase in histamine-mediated vasopermeability in cirrhotic rats but not in control rats. Also albumin distribution space increased more in cirrhotic than in control animals. Heart weight was higher in cirrhotic rats.(ABSTRACT TRUNCATED AT 250 WORDS)     

Evidence of estrogenic effect by the three-month-intervention of isoflavone on vaginal maturation and bone metabolism in early postmenopausal women

Objective of the present study is to determine the estrogenic effect of isoflavone on vaginal epithelia and bone metabolism in early postmenopausal women. Twenty-two postmenopausal women were randomly assigned to either a group that was given isoflavone extract (61.8 mg) for three months or a control group that was given placebo. We measured the L2-4 bone mineral density (BMD) before and 3 months after treatment by dual X-ray absorptiometry (DXA). Blood and urine samples were obtained from the women before and 3 months after treatment. We measured FSH using radioimmunoassay and, urinary pyridinoline and deoxypyridinoline levels by HPLC. For endocrine cytology, vaginal smears were collected before and 3 months after the treatment. Three months after the treatment, the serum FSH levels and the BMD values did not significantly differ between the two groups. Urinary excretion of isoflavone was significantly higher in the group given isoflavone compared with that given placebo (p<0.03). Numbers of parabasal and intermediate types of cells were significantly decreased (58.2 +/- 12.4% to 25.0 +/- 10.7%; p<0.05) and increased (24.1 +/- 8.7% to 63.7 +/- 10.7%; p<0.05), respectively in the isoflavone group, but remained unchanged in the control group. Urinary pyridinoline excretion was significantly decreased (49.6% vs. before, p<0.01 by paired t-test) in the isoflavone group. The intake of 60 mg of isoflavone daily for 3 months produced maturational changes of vaginal epithelia without affecting serum FSH levels, and could possibly slow down bone turnover rates as judged by decreased urinary pyridinoline excretion.     

培哚普利对血压正常的早期糖尿病肾病患者微量白蛋白尿的疗效观察

目的观察培哚普利对血压正常的早期糖尿病肾病患者的白蛋白尿的疗效和对肾功能的保护作用.方法糖尿病患者52例,其尿白蛋白排泄率(AER)均在20～200 μg/min之间,所有患者经控制饮食、口服降糖药物及(或)采用胰岛素治疗使血糖控制在可接受水平(尚可,即空腹血糖<7.0 mmol/L,餐后2 h血糖<10.0 mmol/L),随机分成两组,A组为对照组,25例,在控制血糖基础上加用安慰剂治疗;B组为治疗组,27例,在控制血糖基础上加用培哚普利治疗.培哚普利剂量为4 mg/d.两组患者在治疗前及治疗后3、6、12、18个月复查空腹血糖(FBG)、餐后2 h血糖(PBG)、糖化血红蛋白A1C(HbA1C)和AER等.结果 A组在12、18个月时AER分别为(52.3±8.6) μg/min和(60.5±9.0) μg/min,二者与治疗前的(44.2±6.8)μg/min相比有显著升高(P＜0.05).B组用培哚普利治疗后3、6、12、18个月时AER分别为(20.3±5.6) μg/min、(22.1±6.1) μg/min、(21.3±5.9) μg/min和(20.8±5.7) μg/min,均明显低于同期A组水平(P值均<0.05),与治疗前的(45.3±7.6) μg/min相比,差异亦有显著性(P值均<0.05).结论培哚普利对血压正常的伴有微量白蛋白尿的早期糖尿病肾病患者减少尿蛋白和保护肾功能有良好效果.     

Intervention with the aldose reductase inhibitor,tolrestat, in renal and retinal lesions of streptozotocin-diabetic rats

Summary The progressive increase in urinary albumin excretion, which precedes the development of diabetic nephropathy, can be prevented in diabetic rats if the aldose reductase inhibitor, tolrestat, is administered at the initiation and throughout the duration of hyperglycaemia. We therefore determined the ability of tolrestat to intervene in the further progression of already established urinary albumin excretion of streptozotocin-diabetic female Wistar rats. Two months after streptozotocin injection, diabetic rats were grouped as low-urinary albumin excretion (0.2–1.0 mg albumin/day) or high-urinary albumin excretion (1.9–5.9 mg albumin/day), at which time tolrestat intervention (25 mg/kg per day) was begun for half of the diabetic rats in each urinary albumin excretion group. After six months of treatment tolrestat caused a significant reduction in the urinary albumin excretion rate of the low-urinary albumin excretion group only. The diabetes-induced rise of total urinary protein in both groups was significantly reduced by tolrestat. Furthermore, the diabetes-induced increase (49%) in the thickness of the basement membranes of retinal capillaries from the outer plexiform layer was significantly diminished by tolrestat administration. In conclusion, intervention therapy with the aldose reductase inhibitor, tolrestat, can reduce the progression of urinary albumin excretion and retinal basement membrane thickening in long-term diabetic rats.     

Pioglitazone reduces urinary podocyte excretion in type 2 diabetes patients with microalbuminuria

In various renal diseases, including diabetic nephropathy, detection of podocytes in the urine indicates severe injury to podocytes in the glomeruli. Pioglitazone is a newly developed antidiabetic agent that attenuates insulin resistance. The aim of the present study was to determine whether pioglitazone affects urinary albumin excretion (UAE) or the number of urinary podocytes or both in type 2 diabetes patients with microalbuminuria. Twenty-eight patients with normotensive type 2 diabetes and microalbuminuria (18 men and 10 women; mean age, 52.5 years) and 30 age-matched normotensive controls (20 men and 10 women; mean age, 51.5 years) were included in the study. Urinary podocytes were detected by immunofluorescence with a monoclonal antibody against podocalyxin. Patients were randomly assigned to 2 groups: a pioglitazone-treatment group (30 mg/day, n = 14) and a placebo group (n = 14). Treatment was continued for 6 months. Podocytes were absent in the urine of healthy controls, but detected in 17 of 28 diabetic patients (60.7%). UAE was reduced from 96.7 +/- 50.5 microg/min to 39.7 +/- 22.9 microg/min (P <.01) in the pioglitazone-treatment group, and the number of urinary podocytes was reduced from 0.9 +/- 1.0 cells/mL to 0.1 +/- 0.2 cells/mL (P <.001). Neither UAE nor the number of urinary podocytes was affected in the placebo group. These data indicate that pioglitazone is effective for reducing UAE and podocyte injury in early-stage diabetic nephropathy.     

Effect of alpha-lipoic acid on the progression of endothelial cell damage and albuminuria in patients with diabetes mellitus: an exploratory study

Oxidative stress plays a central role in the pathogenesis and progression of late microangiopathic complications (diabetic nephropathy) in diabetes mellitus. Previous studies suggested that treatment of diabetic patients with the antioxidant alpha-lipoic acid reduce oxidative stress and urinary albumin excretion. In this prospective, open and non-randomized study, the effect of alpha-lipoic acid on the progression of endothelial cell damage and the course of diabetic nephropathy, as assessed by measurement of plasma thrombomodulin and urinary albumin concentration (UAC), was evaluated in 84 patients with diabetes mellitus over 18 months. Forty-nine patients (34 with Type 1 diabetes, 15 with Type 2 diabetes) had no antioxidant treatment and served as a control group. Thirty-five patients (20 with Type 1 diabetes, 15 with Type 2 diabetes) were treated with 600 mg alpha-lipoic acid per day. Only patients with an urinary albumin concentration <200 mg/l were included into the study. After 18 months of follow up, the plasma thrombomodulin level increased from 35.9+/-9.5 to 39.7+/-9.9 ng/ml (P<0.05) in the control group. In the alpha-lipoic acid treated group the plasma thrombomodulin level decreased from 37.5+/-16.2 to 30.9+/-14.5 ng/ml (P<0.01). The UAC increased in patients without alpha-lipoic acid treatment from 21.2+/-29.5 to 36.9+/-60.6 ng/l (P<0.05), but was unchanged with alpha-lipoic acid. It is postulated that the significant decrease in plasma thrombomodulin and failure of UAC to increase observed in the alpha-lipoic acid treated group is due to antioxidative effects of alpha-lipoic acid, and if so that oxidative stress plays a central role in the pathogenesis of diabetic nephropathy. Furthermore, progression of the disease might be inhibited by antioxidant drugs. A placebo-controlled study is needed.     

Long term reduction of microalbuminuria after 1 year of angiotensin converting enzyme inhibition by perindopril in hypertensive insulin-treated diabetic patients

We studied the effects of perindopril, an angiotensin converting enzyme (ACE) inhibitor administered during 12 months, on creatinine clearance, albuminuria and glycaemic control in diabetic subjects with mild to moderate hypertension. After 1 month placebo, 40 insulin-treated patients were divided into 3 groups based upon their urinary albumin excretion rate (AER). Group I had a normoalbuminuria (AER less than 15 mg/24 h), group II had a microalbuminuria (AER : 15-150 mg/24 h) and group III had a macroproteinuria (AER greater than 150 mg/24 h and Albustix (+)). They were given perindopril, 4 to 8 mg orally once daily, and received a stable diet. Diastolic blood pressure was normalized within the first 3 months in 80% of the patients. From these, 28 (14.7 and 7 from groups I, II and III respectively) were followed during a total active treatment period of 12 months. They were matched for age, duration of diabetes and hypertension, systolic and diastolic blood pressures, daily insulin dose, postprandial plasma C-peptide and quality of glycaemic control. Mean supine diastolic blood pressure was decreased by 15 and 18% at 1 and 12 months respectively. Heart rate was not significantly modified. At 3 months, plasma ACE activity was nearly totally inhibited while plasma renin activity was markedly increased. In patients of group II, microalbuminuria was reduced from 66 +/- 13 (mean +/- SEM after placebo) to 39 +/- 6 mg/24 h after 1 month perindopril and this effect was maintained at 12 months. In group I, albuminuria remained within the normal range. In group III, macroproteinuria was not consistently modified by perindopril.(ABSTRACT TRUNCATED AT 250 WORDS)     

Effects of oral administration of L-arginine on renal function in patients with heart failure

OBJECTIVES: Although the beneficial effects of L-arginine on systemic haemodynamics have been reported in patients with heart failure, its effect on renal function has not been examined. We evaluated the effects of oral administration of L-arginine on renal haemodynamics, sodium and water handling, and various hormonal factors in patients with chronic heart failure. SUBJECTS AND METHODS: A double-blind crossover trial was performed in 17 patients with chronic congestive heart failure (NYHA II-III, 56 +/- 12 years of age) who were randomly assigned to receive oral L-arginine (15 g/day) and placebo or placebo and arginine sequentially for 5 days each. Twenty-four hour creatinine clearance (Ccr), and 24-h urinary cyclic guanosine 5-monophosphate (GMP) excretion were determined. Saline loading was performed on day 5 of each treatment Renal blood flow, glomerular filtration rate (GFR), and urinary sodium excretion rate (UNa) were assessed before and after saline loading. RESULTS: Twenty-four hour GMP excretion (1.4 +/- 1.1 versus 0.8 +/- 0.5 micromol/day, P < 0.01) and Ccr (150 +/- 43 versus 125 +/- 42 ml/min, P < 0.05) were higher and plasma endothelin level (2.5 +/- 0.6 versus 3.1 +/- 0.8 pg/ml, P < 0.05) was lower with L-arginine treatment compared to placebo treatment In addition, the relative increase of UNa and GFR after saline loading were significantly higher in L-arginine treatment (UNa, 47 +/- 12%; GFR, 44 +/- 31%) than in placebo treatment (UNa, 34 +/- 9%; GFR, 22 +/- 29%) (P < 0.05). CONCLUSIONS: Oral administration of L-arginine has beneficial effects on glomerular filtration rate, natriuresis, and plasma endothelin level in patients with chronic congestive heart failure.     

The effect of six months continuous subcutaneous insulin infusion on kidney function and size in insulin-dependent diabetics

Glomerular filtration rate (GFR), renal plasma flow (RPF), kidney volume, and urinary albumin excretion rate were measured in 24 insulin-dependent diabetics, aged 29 +/- 7 years (mean +/- S.D.) of 8 +/- 4 years duration, randomly allocated to either continuous subcutaneous insulin infusion (CSII) (n = 12) or unchanged conventional insulin treatment (CIT) (n = 12). Glomerular filtration rate, renal plasma flow, and kidney volume were identical in the two groups at the start of the study, although significantly increased above normal values. During the 6 months CSII treatment a reduction of the GFR from 145 +/- 21 to 132 +/- 14 ml/min (2p = 2.4%) was seen, no change was observed in the CIT group while in both groups RPF and kidney volume remained unchanged. Urinary albumin excretion rate was normal or near normal in both groups and remained unchanged. Thus improved glycaemic control in insulin-dependent diabetics studied before the onset of microalbuminuria is associated with improved (reduced) GFR. Nephromegaly does not improve with 6 months CSII treatment. Whether it would improve with more prolonged treatment is uncertain.     

Beneficial effects of C-peptide on incipient nephropathy and neuropathy in patients with Type 1 diabetes mellitus.

AIMS: Recent studies have indicated that proinsulin C-peptide shows specific binding to cell membrane binding sites and may exert biological effects when administered to patients with Type 1 diabetes mellitus. This study was undertaken to determine if combined treatment with C-peptide and insulin might reduce the level of microalbuminuria in patients with Type 1 diabetes and incipient nephropathy. METHODS: Twenty-one normotensive patients with microalbuminuria were studied for 6 months in a double-blind, randomized, cross-over design. The patients received s.c. injections of either human C-peptide (600 nmol/24 h) or placebo plus their regular insulin regimen for 3 months. RESULTS: Glycaemic control improved slightly during the study and to a similar extent in both treatment groups. Blood pressure was unaltered throughout the study. During the C-peptide treatment period, urinary albumin excretion decreased progressively on average from 58 microg/min (basal) to 34 microg/min (3 months, P < 0.01) and it tended to increase, but not significantly so, during the placebo period. The difference between the two treatment periods was statistically significant (P < 0.01). In the 12 patients with signs of autonomic neuropathy prior to the study, respiratory heart rate variability increased by 21 +/- 9% (P < 0.05) during treatment with C-peptide but was unaltered during placebo. Thermal thresholds were significantly improved during C-peptide treatment in comparison to placebo (n = 6, P < 0.05). CONCLUSION: These results indicate that combined treatment with C-peptide and insulin for 3 months may improve renal function by diminishing urinary albumin excretion and ameliorate autonomic and sensory nerve dysfunction in patients with Type 1 diabetes mellitus.     

培哚普处比硝苯地平能更有效降低高血压病患者的尿蛋白排泄

目的 探讨硝苯地平和培哚早长期治疗对高血压病患肾功能的影响。方法 ５２例高血压病患发为两组：硝苯地平组（２６例）和培哚普利组（２６例）,疗程２４周,治疗前后观察肾功能指标变化。结果 （１）两种药物能同等程度降低各组高血压病患的动脉血压,培哚普处组高血压病患治疗后能显降低尿蛋白排泄量,升高肾小球滤过率「２４小时尿白蛋白（ｍｇ／２４ｈ）;１０４．５±４１．８降至６６．７±２５．９,Ｐ〈０．０     

Antiproteinuric effect of niceritrol,a nicotinic acid derivative,in chronic renal disease with hyperlipidemia: a randomized trial

PURPOSE: Lipoprotein (a) [Lp(a)] levels increase in patients with renal disease. We administered niceritrol, a nicotinic acid derivative, to patients with chronic renal disease and a high serum Lp(a) level, and studied its effects on lipid metabolism, proteinuria, and renal function. METHODS: Thirty-three patients with chronic renal disease whose serum Lp(a) levels were > or = 15 mg/dL were randomly (but not blindly) assigned to treatment with niceritrol (n = 16) or to an untreated control group (n = 17). Parameters of lipid metabolism, excretion of urinary protein, and renal function were examined for 12 months. RESULTS: Changes in urinary protein excretion, as well as Lp(a) levels, differed significantly between the two groups. The mean (+/- SD) change from baseline in excretion of urinary protein was 0.77 +/- 1.23 g/d in the control group compared with -1.41 +/- 2.26 g/d in the niceritrol group at 12 months (P =0.003). Mean Lp(a) levels increased by 3 +/- 10 mg/dL in the control group compared with a decrease of 10 +/- 13 mg/dL in the niceritrol group at 12 months (P =0.004). The mean creatinine clearance declined by 10 +/- 12 mL/min in the control group, compared with 1 +/- 13 mL/min in the niceritrol group at 12 months (P =0.06). CONCLUSION: Lipid levels improved with niceritrol treatment, whereas the excretion of urinary protein decreased, perhaps slowing the rate of loss of renal function in chronic renal disease.     

Long-term effects of pravastatin and fosinopril on peripheral endothelial function in albuminuric subjects

The purpose of this double-blind, randomized, placebo-controlled trial was to determine the long-term effects of pravastatin and fosinopril treatment on peripheral endothelial function in subjects with albuminuria. Subjects (mean age 51 years, 63% male) were randomized to pravastatin 40 mg or matching placebo and to fosinopril 20mg or matching placebo. Using high resolution ultrasound, flow-mediated dilation (FMD) and nitroglycerin-induced dilation (NID) was assessed at baseline and after 4 years of treatment in a total of 276 subjects. At baseline, mean+/-standard error FMD was 4.73+/-0.49% and NID was 10.86+/-0.67%. Pravastatin significantly reduced total cholesterol and LDL cholesterol (p<0.01) and randomization to pravastatin was associated with a non-significant improvement of 18.9% in FMD (+0.80+/-0.95, p=0.09), without a significant change in NID. Interestingly, pravastatin significantly increased FMD by 34.9% in men (+1.23, p=0.04), but only 1.1% in women (+0.06, p=0.95). Fosinopril was not associated with a change in FMD or NID despite significantly decreasing urinary albumin excretion, systolic and diastolic blood pressure (all p<0.01). In conclusion, after 4 years of follow-up, pravastatin treatment tended to increase FMD and this effect was predominantly present in men. Fosinopril treatment did not modify FMD during long-term follow-up.     

Comparative effects of pioglitazone, glibenclamide, and voglibose on urinary endothelin-1 and albumin excretion in diabetes patients

Urinary endothelin (ET)-1 excretion is present in non-insulin dependent diabetes (NIDDM) patients with microalbuminuria, and an increase in circulating ET-1 precedes the microalbuminuric phase of renal injury related to diabetes. The aim of the present study was to determine whether various drugs alter urinary ET-1 levels and urinary albumin excretion (UAE) in NIDDM patients with microalbuminuria. Forty-five NIDDM patients with microalbuminuria were randomly assigned to three groups: those treated with pioglitazone at 30 mg/day (n=15), those treated with glibenclamide at 5 mg/day (n=15), and those treated with voglibose at 0.6 mg/day (n=15). Patients received these drugs for 3 months. UAE, urinary ET-1, and plasma ET-1 levels were measured in these patients before and after treatment. Before treatment, UAE, urinary ET-1, and plasma ET-1 levels differed little among the three groups. UAE in the 45 NIDDM patients (156.2+/-42.8 microg/min) was greater than that in 30 healthy controls (8.2+/-2.6 microg/min) (P<.001). Urinary ET-1 levels in the NIDDM patients (8.7+/-1.3 ng/g urinary creatinine (UC)) were significantly higher than that in the controls (2.4+/-0.2 ng/g UC) (P<.01). Plasma ET-1 levels, however, in the NIDDM patients (1.3+/-0.4 pg/ml) did not differ significantly from the levels in healthy controls (1.0+/-0.6 pg/ml). Pioglitazone but no glibenclamide or voglibose reduced UAE from 142.8+/-42.2 to 48. 4+/-18.2 microg/min (P<.01) and urinary ET-1 levels from 8.6+/-1.3 to 3.4+/-0.5 ng/g UC (P<.01). These data suggest pioglitazone to be effective in reducing UAE and urinary ET-1 concentrations in NIDDM patients with microalbuminuria.     

Comparison of long-term therapeutic effect of an ACE inhibitor, temocapril, with that of a diuretic on microalbuminuria in non-diabetic essential hypertension.

Many investigators have reported that angiotensin-converting enzyme (ACE) inhibitors have antiproteinuric effects and retard the progression of renal impairment in diabetic patients. On the other hand, those effects of ACE inhibitors have not been well established in patients with essential hypertension. This study was conducted to prospectively evaluate whether an ACE inhibitor, temocapril, could modify the urinary microalbumin excretion rate (UAE) in hypertensive outpatients who had no signs of renal impairment. To compare the long-term effect of temocapril with that of a diuretic on UAE, hypertensive patients treated with a diuretic (trichlormethiazide) were enrolled in a prospective study if they had normal serum creatinine levels and no overt proteinuria during a 3-month screening period. A urinary microalbumin-to-urinary-creatinine ratio (mg albumin/mmol Cr) was used as an estimate of UAE. Patients visited the hospital monthly to determine blood pressure (BP) and UAE. After baseline observation during the treatment with the diuretic, the subjects were randomly divided into two groups. In group A, the diuretic was switched to temocapril, 2 to 4 mg once daily for 12 months. In group B, the subjects continued to receive the diuretic for an additional 12 months. Seventy-six outpatients (41 men and 35 women; mean age, 59.0+/-1.4 years) with essential hypertension entered the study. The effects of temocapril on BP appeared to be clinically similar to those of the trichlormethiazide, but the use of temocapril significantly decreased UAE. In group A (n=37), UAE decreased significantly (p<0.01) from the baseline value of 4.19+/-0.37 mg albumin/mmol Cr to 2.47+/-0.29 and 2.68+/-0.28 mg albumin/mmol Cr at the 6th and 12th month of temocapril therapy, respectively. In contrast, in group B (n=39) UAE was unchanged (baseline, 4.16+/-0.63 mg albumin/mmol Cr; 6 months, 4.92+/-0.72; 12 months, 4.71+/-0.74). These results indicate that long-term therapy with temocapril may be superior in reducing UAE than is diuretic therapy in patients with essential hypertension who had no signs of renal impairment.     

Alendronate in primary hyperparathyroidism: a double-blind, randomized, placebo-controlled trial

Primary hyperparathyroidism (PHPT) is often associated with reduced bone mineral density (BMD). A randomized, double-blind, placebo-controlled trial was conducted to determine whether alendronate (ALN), 10 mg daily, maintains or improves BMD in patients with PHPT. Eligible patients had asymptomatic PHPT and did not meet surgical guidelines or refused surgery. Forty-four patients randomized to placebo or active treatment arms were stratified for gender. At 12 months, patients taking placebo crossed over to active treatment. All patients were on active treatment in yr 2. The primary outcome index, BMD, at the lumbar spine (LS), femoral neck, total hip, and distal one third radius was measured every 6 months by dual-energy x-ray absorptiometry. Calcium, phosphorous, PTH, bone-specific alkaline phosphatase (BSAP) activity, urinary calcium, and urinary N-telopeptide (NTX) excretion were monitored every 3 months. Treatment with alendronate over 2 yr was associated with a significant (6.85%; micro(d) = 0.052; +/-0.94% se; P < 0.001) increase in LS BMD in comparison with baseline. Total hip BMD increased significantly at 12 months with alendronate by 4.01% (micro(d) = 0.027; +/-0.77% se; P < 0.001) from baseline and remained stable over the next 12 months of therapy. BMD at the one third radius site did not show any statistically significant change in the alendronate-treated group at 12 or 24 months of therapy. At 24 months, the alendronate-treated group showed a 3.67% (micro(d) = 0.022; +/-1.63% se; P = 0.038) gain in bone density at the femoral neck site in comparison with baseline. The placebo group, when crossed over to alendronate at 12 months, showed a significant change of 4.1% (micro(d) = 0.034; +/-1.12% se; P = 0.003) in the LS BMD and 1.7% (micro(d) = 0.012; +/-0.81% se; P = 0.009) at the total hip site in comparison with baseline. There was no statistically significant change seen in the placebo group at 12 months at any BMD site and no significant change at 24 months for the distal one third radius or femoral neck sites. Alendronate was associated with marked reductions in bone turnover markers with rapid decreases in urinary NTX excretion by 66% (micro(d) = -60.27; +/-13.5% se; P < 0.001) at 3 months and decreases in BSAP by 49% at 6 months (micro(d) = -15.98; +/-6.32% se; P < 0.001) and by 53% at 9 and 12 months (micro(d) = -17.11; +/-7.85% se; P < 0.001; micro(d) = -17.36; +/-6.96% se; P < 0.001, respectively) of therapy. In the placebo group, NTX and BSAP levels remained elevated. Serum calcium (total and ionized), PTH, and urine calcium did not change with alendronate therapy. In PHPT, alendronate significantly increases BMD at the LS at 12 and 24 months from baseline values. Significant reductions in bone turnover occur with stable serum calcium and PTH levels. Alendronate may be a useful alternative to parathyroidectomy in asymptomatic PHPT among those with low BMD.     

Low-dose candesartan cilexetil prevents early kidney damage in type 2 diabetic patients with mildly elevated blood pressure.

To determine the effect of a low-dose angiotensin receptor blocker, candesartan, on early kidney damage associated with diabetes. Fifty-two patients with type 2 diabetes with normo- and microalbuminuria participated in this study. Nineteen patients with high-normal and mildly high blood pressure received low-dose candesartan cilexetil at 4 mg daily (candesartan group), and 33 patients did not receive candesartan (control group). Blood pressure, urinary excretion of albumin, transferrin, and type IV collagen (expressed as urinary creatinine index) and plasma parameters were determined at baseline and at 2, 6, 12 and 18 months after the start of candesartan therapy. Baseline urinary albumin, transferrin, and type IV collagen excretions was similar in the control and candesartan groups. The higher baseline systolic blood pressure was decreased by candesartan treatment to a level similar to that in the control group, such that blood pressure was comparable between the control and candesartan groups during the run-in period. In the control group, urinary albumin excretion was significantly increased at 18 months when compared with baseline, while urinary albumin excretion did not increase in the candesartan group throughout the study. Urinary transferrin excretion was significantly increased at 6, 12, and 18 months when compared with baseline in the control group, while it did not increase in the candesartan group during the study. In both groups, urinary type IV collagen excretion did not change significantly during the study. Hemoglobin A1c, serum urea nitrogen, creatinine, albumin, and lipids were comparable between the two groups throughout the study. In conclusion, low-dose candesartan can prevent early kidney damage in type 2 diabetic patients with mildly higher blood pressure independently of its hypotensive action.