Microalbuminuria: a major risk factor in non-insulin-dependent diabetes. A 10-year follow-up study of 503 patients

Clinical factors associated with urinary albumin excretion in type II diabetes

Clinical factors associated with urinary albumin excretion (UAE) in type II diabetes are less well known than in type I diabetes. To examine the factors associated with UAE in type II diabetes, 933 Appropriate Blood Pressure Control in Diabetes Trial patients were classified according to UAE status: normoalbuminuria (< 20 micrograms/min), microalbuminuria (20 to 200 micrograms/min), and macroalbuminuria (> 200 micrograms/min). The class of UAE was then correlated with various clinical factors. Using univariate analyses, Hispanic ethnicity, African-American race, male gender, poor glycemic control, insulin use, long duration of diabetes, dyslipidemia, diastolic and systolic hypertension, smoking, and obesity were significantly correlated with microalbuminuria and macroalbuminuria. Using multivariate logistic regression analyses controlling for diabetes duration, glycosylated hemoglobin, gender, and race, the most significant predictors of microalbuminuria and macroalbuminuria were systolic hypertension, body mass index, high-density lipoprotein cholesterol, insulin use, and smoking pack-years. Of these factors, several are potentially reversible with aggressive intervention.

Albuminuria in association with insulin and sodium-lithium countertransport in young African Americans with borderline hypertension

The purpose of this study was to determine whether early nephropathy, evidenced by urinary albumin excretion, can be detected in young African American subjects with only borderline hypertension, and whether there is a relationship of albuminuria with insulin resistance and with sodium-lithium countertransport activity. Clinically well young African American men and women including normotensive (blood pressure < 135/85 mm Hg, n = 41) and borderline hypertensive (blood pressure > or = 135/85 mm Hg, n = 26) individuals were studied. Each subject underwent an oral glucose tolerance test and euglycemic hyperinsulinemic clamp study. Albuminuria was measured on timed urine collections. Sodium-lithium countertransport activity was assayed in fresh red blood cells at 280 mmol/L Na+ for full saturation of external Na+ sites. The sum of insulin levels during glucose tolerance was significantly greater in the borderline hypertensive compared with the normotensive subjects (P = .014), and insulin-stimulated glucose utilization during the clamp was significantly lower in borderline hypertensive compared with normotensive subjects (P = .016). Albuminuria was greater in borderline hypertensive compared with normotensive subjects (P = .002). Albuminuria was significantly correlated with fasting plasma insulin concentration (r = .44, P < .002) and the sum of insulins during the glucose tolerance test (r = .45, P < .002). Sodium-lithium countertransport correlated with albuminuria (r = .31, P < .05) as well as significantly with insulin-stimulated glucose utilization during the clamp (r = .44, P < .001).(ABSTRACT TRUNCATED AT 250 WORDS)

The effects of metformin on the capillary permeability to albumin in women patients with cyclic edema

An experimental work has suggested the efficacy of metformin, an oral antidiabetic agent, on capillary permeability. This agent has been tested in 10 women patients with cyclic edema, 7 of them being obese. The capillary permeability to albumin studied by an isotope test derived from Landis's method was initially increased. After a mean of six-weeks of treatment the albumin retention and an index demonstrating the interstitial protein elimination through the lymph route were significantly improved. Concomitantly, the swelling feelings were reduced in 8 cases and the lower limb edema had decreased or disappeared in 8 of 9 patients who initially presented these symptoms. The effects of metformin are beneficial and have been observed to be independent of glycemic change. The results suggest a special effect of this agent on the microcirculation. Nevertheless, a controlled study is required.

Albumin excretion and vascular deaths in NIDDM

Non-insulin-dependent diabetes mellitus (NIDDM) is associated with premature mortality, generally thought to be exaggerated in patients with microalbuminuria. This prospective 8-year follow-up study aimed to determine outcome, mortality and cause of death in NIDDM patients with abnormal urinary albumin excretion compared to those with normal albumin excretion. We recruited 153 NIDDM patients with abnormal urinary albumin excretion and 153 control subjects with albumin excretion within the normal non-diabetic range, matched for age, sex and duration of diabetes, from three University hospital diabetic clinics in Newcastle upon Tyne. The outcome measures were status at follow-up, mortality and cause of death. Subjects with abnormal albumin excretion had a significantly higher 8-year mortality than matched control subjects (Odds Ratio 1.47, p = 0.02; 108 vs 66 per 1000 person years follow-up, p < 0.001). This difference was seen at all levels of abnormal albumin excretion, from just outside the normal range (10.6-29.9 microgram/min: 104 vs 61 per 1000 person years follow-up, p < 0.001) to more conventional definitions of microalbuminuria (> or = 30 micrograms/min: 111 vs 71 per 1000 person years follow-up, p < 0.01). Those with abnormal albumin excretion had an excess of vascular deaths compared to matched control subjects (Odds Ratio 1.70, p = 0.009), again at different levels of albumin excretion (10.6-29.9 micrograms/min p < 0.01, 30-150 micrograms/min p < 0.05). On multivariate analysis, age, initial ischaemic heart disease and initial albumin excretion rates were independent predictors of death from all causes.(ABSTRACT TRUNCATED AT 250 WORDS)

Long-term effect of eicosapentaenoic acid ethyl (EPA-E) on albuminuria of non-insulin dependent diabetic patients

Dietary cod-liver oil containing eicosapentaenoic acid is effective on microvascular albumin leakage in diabetic patients with albuminuria. We determined the long-term effects of oral pure eicosapentaenoic acid ethyl (EPA-E: 900 mg/day) administration on diabetic nephropathy in non-insulin dependent diabetic (NIDDM) patients. The effects of EPA-E were determined by observing the changes of the index of urine albumin excretion level/urine creatinine (Cr) excretion level (UAI), the ratio of beta 2-microglobulin excretion level/urine Cr excretion level (beta 2-MG/Cr) and the ratio of N-acetyl-D-glucosaminidase excretion level/urine Cr excretion level (NAG/Cr) at 3, 6 and 12 months after the start of the treatment. Oral EPA-E administration immediately improved the increased UAI at 3 months after the start of treatment. A significant improvement of the UAI by EPA-E was sustained 12 months later. EPA E administration also tended to decrease the urine beta 2-MG/Cr ratio from 6 months, but the difference was statistically not significant. However, the urine NAG/Cr ratio was not changed by EPA-E administration. EPA-E administration did not affect blood pressure levels, glycemic control and lipid metabolism in these patients. The present data indicated that EPA-E administration improved increased albumin excretion in NIDDM patients with nephropathy and its effects on albuminuria sustained for at least 12 months after the start of treatment. However, tubular factors were not influenced by EPA-E administration.

Insulin resistance and abnormal albumin excretion in non-diabetic first-degree relatives of patients with NIDDM

Microalbuminuria has recently been associated with insulin resistance in both insulin-dependent and non-insulin-dependent (NIDDM) diabetes mellitus. To establish whether microalbuminuria in non-diabetic subjects as well is associated with insulin resistance and associated abnormalities in glucose and lipid metabolism, oral glucose tolerance tests were performed with measurement of urinary albumin excretion rate, lipids and lipoproteins in 582 male non-diabetic first-degree relatives of patients with NIDDM. In addition, insulin sensitivity was assessed in 20 of these subjects with the euglycaemic hyperinsulinaemic clamp technique. Abnormal albumin excretion rate (AER), defined as AER 15-200 micrograms/min, was associated with higher systolic blood pressure (p < 0.05), higher fasting glucose values (p < 0.05), lower HDL-cholesterol (p < 0.05) and lower apolipoprotein A-I (p < 0.05) concentrations than observed in subjects with normal AER. The rate of glucose metabolism was lower in subjects with abnormal compared to subjects with normal albumin excretion rate (38.0 +/- 2.8 vs 47.3 +/- 2.4 mumol.kg lean body mass-1.min-1; p = 0.028). This difference was almost completely accounted for by a reduction in non-oxidative glucose metabolism (17.7 +/- 1.9 vs 27.4 +/- 2.7 mumol.kg lean body mass-1.min-1; p = 0.010), which correlated inversely with the AER (r = -0.543; p = 0.013). These results suggest that in non-diabetic individuals genetically predisposed to NIDDM, abnormal AER is associated with insulin resistance and abnormalities in glucose and lipid metabolism.

Microalbuminuria as identified by a spot morning urine specimen in non-insulin-treated diabetes: an eight-year follow-up study

This study followed up a cohort of patients with microalbuminuria identified on a spot morning urine sample 8 years earlier and aimed to determine if a spot morning urinary albumin concentration was able to identify patients with non-insulin treated diabetes at increased risk of mortality and progression to nephropathy. In 1984, 47 of 216 patients chosen by random selection from our teaching hospital-based diabetes clinic were identified as having microalbuminuria (urinary albumin concentration 35-300 micrograms ml-1). Subjects were compared with an age-matched control group from the 1984 cohort who did not have microalbuminuria. Eight years later, 22 of 47 (46.8%) patients with microalbuminuria had died compared to 10 of 47 (21.3%) patients without albuminuria (p < 0.05). The majority of deaths were from cardiovascular disease (53.1%). Logistic regression showed microalbuminuria to be an independent predictor of mortality, not influenced by age, duration of diabetes, blood pressure, glycosylated haemoglobin or creatinine at the initial examination. Eight years later, in the group with initial microalbuminuria, eight still had microalbuminuria and five patients had developed nephropathy. In the group without albuminuria in 1984, only one patient had progressed to microalbuminuria and no patients to nephropathy. In conclusion, a spot urinary albumin concentration is of value in identifying patients with an increased risk of mortality or progression to nephropathy, and is simple to obtain at a clinic.

The relationship of urinary albumin excretion rate to ambulatory blood pressure and erythrocyte sodium-lithium countertransport in NIDDM

Increased erythrocyte sodium-lithium countertransport rate is found in non-diabetic subjects with essential hypertension, and in insulin-dependent diabetic subjects with nephropathy. However, relationships between these variables in non-insulin-dependent diabetic subjects are ill-defined. In order to characterise the relationships between blood pressure, urinary albumin excretion, and erythrocyte sodium-lithium countertransport, 66 subjects with non-insulin-dependent diabetes were studied. Urinary albumin excretion rate correlated with mean 24-h ambulatory systolic blood pressure (r = 0.57; p < 0.001), but not with sodium-lithium countertransport (r = 0.06; p = 0.31). No significant relationship was observed between 24-h systolic blood pressure and erythrocyte sodium-lithium countertransport (r = 0.16; p = 0.17). The principal differences between microalbuminuric and normoalbuminuric subjects (albumin excretion rate > 15 micrograms.min-1 [n = 20], and < 15 micrograms.min-1, [n = 46]) were: higher 24-h systolic blood pressure (145.9 [16.8] mmHg vs 131.9 [16.8] mmHg; p = 0.006), nocturnal heart rate (72.4 [8.9] vs 67.4 [8.9] beats.min-1; p = 0.042), and HbA1 (11.3 [1.5]% vs 10.1 [2.0]%; p = 0.028), and a longer median duration of diabetes (10.0 vs 5.0 years; p = 0.02). In contrast, there was no significant difference in sodium-lithium countertransport rate between microalbuminuric (0.41 [0.18] mmol.l-1.h-1) and normoalbuminuric subjects (0.39 [0.15] mmol.l-1.h-1; p = 0.687).(ABSTRACT TRUNCATED AT 250 WORDS)

Microalbuminuria, insulin sensitivity and haemostatic factors in non-diabetic treated hypertensive men. Risk Factor Intervention Study Group

OBJECTIVE

To examine whether microalbuminuria in non-diabetic, treated hypertensive men is associated with insulin resistance and measures of endothelial function, thrombogenesis and fibrinolysis.

DESIGN

Cross-sectional study.

SETTING

Outpatient clinic in city hospital.

PATIENTS

Ninety-two treated hypertensive men, aged 57-77 years, either with a serum cholesterol of > or = 6.5 mmol L-1 or smokers, or both. Patients with diabetes mellitus or overnight urinary albumin excretion of > 100 mg 12 h-1 were excluded.

MAIN OUTCOME MEASURES

Overnight urinary albumin excretion, insulin-mediated glucose disposal (hyperinsulinaemic euglycaemic clamp), blood glucose and plasma insulin during oral glucose tolerance test, fibrinogen, von Willebrand factor and plasminogen activator inhibitor activity.

RESULTS

Microalbuminuric patients had increased blood glucose concentrations during the oral glucose tolerance test and higher plasma fibrinogen levels compared with the normoalbuminuric patients. In a randomly selected subgroup (n = 36), insulin-mediated glucose disposal was lower in microalbuminuric than in normoalbuminuric patients, and an inverse relationship between insulin sensitivity and albuminuria (r = -0.37; P = 0.028) was found. This relationship was not significant after adjustment for body-mass index (P = 0.098). In the univariate analyses including all patients, albuminuria was associated with blood glucose, serum creatinine, body-mass index, systolic blood pressure, fibrinogen, von Willebrand factor and cholesterol (negatively). In a multiple regression analysis, only the body-mass index was independently related to urinary albumin excretion.

CONCLUSIONS

Microalbuminuria was associated with insulin resistance but obesity was a confounding factor. Relationships between microalbuminuria and fibrinogen as well as von Willebrand factor were found, but only in univariate analysis.

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

The relation between proteinuria and mortality was investigated in 1188 patients with Type 1 diabetes and 3234 patients with Type 2 diabetes, aged 35-55 at baseline and followed up for a mean of 9.4 +/- 3.1 years in the WHO Multinational Study of Vascular Disease in Diabetes. Baseline prevalence of light or heavy proteinuria was the same (25%) in both types of diabetes after adjustment for differences in diabetes duration. Compared with patients with no proteinuria, all cause mortality ratios were 1.5 (95% confidence interval 1.1-2.0) and 2.9 (2.2-3.8) for Type 1 patients with light and heavy proteinuria, respectively, and 1.5 (1.2-1.8) and 2.8 (2.3-3.4) for Type 2 patients, after adjustment for age, duration of diabetes, blood pressure, cholesterol, and smoking. Proteinuria was associated with significantly increased mortality from renal failure, cardiovascular disease, and all other causes of death. In both types of diabetes, the association was strongest for renal deaths, and of similar magnitude for cardiovascular and all other causes of death. In conclusion, proteinuria is a common, important, and rather non-specific risk factor for increased morbidity and mortality in diabetes. The relation of proteinuria to mortality is similar for both types of diabetes. The benefits and risks of proteinuria reduction should be examined in large randomized trials with clinical endpoints.

Type II diabetic nephropathy in perspective

The magnitude of type II diabetic nephropathy dilemma is observable in the growing number of diabetic patients with end-stage renal lesion receiving various modalities of treatment. Progressive glomerulopathy associated with proteinuria and hypertension is strongly causative of renal failure and mortality in diabetic patients. Besides hypertension, diabetes exceeds all other glomerulopathies in causing end-stage renal failure. Alterations in glomerular structure and function observed in diabetic patients are implicated in the development and progression of renal derangement. Diabetic glomerulosclerosis, an aggregate of structural and functional perturbations of the kidney, is indicated by alterations in the accumulation of extracellular matrix components, The pathology, epidemiology, risk factors, and other dependent variables may throw some light in the pathogenetic mechanisms and the prevention, treatment, and management modalities of type II diabetic nephropathy.

[Diabetes mellitus and atherosclerosis. Physiopathology of diabetic macroangiopathy]

Numerous prospective epidemiological studies point out high mortality prevalence in diabetic subjects. Classical risk factors, especially arterial hypertension and hypertriglyceridaemia, are abnormally associated with diabetes mellitus. However, they don't account for overall surmortality in this disease. Additional markers of cardiovascular risk appeared as albuminuria, abdominal obesity, and the couple insulinoresistance/hyperinsulinism. Physiopathological intrinsic mechanisms inherent to macroangiopathy are multiple and intricate (hemostatic disorders, endothelial impairments, oxidative stress, quantitative and qualitative lipoproteins abnormalities, part of hyperinsulinism and growth factors). Strict normoglycaemia and exacting control of all other risk factors is essential. Use of other therapeutic agents as antioxidants and antiagregants, is discussed.

Prevalence of microalbuminuria in Saudi Arabians with non-insulin-dependent diabetes mellitus: a clinic-based study

Prevalence of diabetic nephropathy varies in different racial groups, being especially high in communities that have abandoned an active traditional living and embraced a modern but sedentary life-style. As a new and rapidly developing country, Saudi Arabia has witnessed impressive changes in socio-economic growth and development and concurrently, a disturbing trend in non-insulin-dependent diabetes mellitus (NIDDM). These observations therefore prompted us to investigate the prevalence of microalbuminuria among Saudi Arabians with NIDDM. Two hundred and eleven patients attending a large Diabetic Clinic in Riyadh were screened for microalbuminuria (30-300 mg/24 h). Twenty-seven subjects had clinical proteinuria (dipstick-positive) and were excluded, leaving 184 cases for analysis. Seventy-six subjects (76/184, 41.3%) had microalbuminuria. These subjects had higher fasting plasma glucose concentrations (P = 0.002) and greater body mass index (P = 0.049) than subjects with normal albumin excretion rate (< 30 mg/24 h). There were no significant differences between subjects with and without microalbuminuria with regards to fasting total plasma cholesterol and triglycerides concentrations, frequency of hypertension, duration of diabetes or type of therapy for diabetes. In multivariate analysis, glycaemia (P < 0.005) and years since diagnosis of diabetes (P = 0.05) remained independently associated with albumin excretion rate. We conclude that microalbuminuria is exceedingly common in a clinic-based population of Saudi Arabians with NIDDM and its presence is closely related to glycaemic control. Whether the prevalence of microalbuminuria is truly increased in the diabetic population at large in Saudi Arabia must now await further population-based studies.

Effects of captopril treatment versus placebo on renal function in type 2 diabetic patients with microalbuminuria: a long-term study

We evaluated the renal effect of long-term antihypertensive treatment (12 months) with the angiotensin-converting enzyme inhibitor captopril compared to placebo in 15 type 2 diabetic patients with microalbuminuria. The patients were randomly allocated to captopril (n = 9) or placebo (n = 6). After 1-year therapy no significant decrease in blood pressure was demonstrated with captopril (139 +/- 17/80 +/- 9 versus 138 +/- 13/76 +/- 6 mmHg) or placebo (138 +/- 9/75 +/- 6 versus 135 +/- 14/79 +/- 10 mmHg). Only in a small hypertensive subgroup (n = 4) treated with captopril did we find a significant reduction in blood pressure (154 +/- 2/88 +/- 1 versus 142 +/- 7/78 +/- 5 mmHg, P < 0.05). The urinary albumin excretion rate did not change significantly either in the captopril group (95.6 mg/24 h, 25th percentile 138.4, 75th percentile 25.1; versus 127.8 mg/24 h, 25th percentile 29.3, 75th percentile 222) or in the placebo group (99.2 mg/24 h, 25th percentile 58.5, 75th percentile 125.8; versus 120.9 mg/24 h, 25th percentile 62.1, 75th percentile 179.7). There were also no alterations in renal blood flow or filtration rate. In the hypertensive subgroup treated with captopril a reduction in urinary albumin excretion rate after 3 and 6 months of treatment was observed (captopril 73.4 versus 24 and 41 mg/24 h, P < 0.05), but not after 12 months. Triglyceride and cholesterol levels remained constant before and after treatment while glycosylated hemoglobin decreased significantly after 12 months captopril (7.8 +/- 0.9 versus 6.9 +/- 0.7 mg%, P < 0.03).(ABSTRACT TRUNCATED AT 250 WORDS)

Systolic blood pressure relates to the rate of progression of albuminuria in NIDDM

We prospectively followed a cohort of 278 non-insulin-dependent (NIDDM) patients for a 6-year period, intending to estimate the rate of increase of albuminuria and to identify clinical variables that influence this increase. At baseline, normo-albuminuria (N) was seen in 74%, microalbuminuria (M) in 19% and 7% presented with proteinuria (P). A total of 80 patients died; they were older (p < 0.001) and had higher albumin excretion both at baseline and as an average during follow-up (p < 0.01). At baseline, patients with proteinuria had higher blood pressures (systolic and diastolic), whereas there was no difference between patients with normo-and microalbuminuria. Glycaemic control was increasingly poor throughout the three groups. At follow-up, an average relative rate of increase of albuminuria (slope) of 17% per year was seen both for patients with complete 6 years, follow-up (n - 135) and patients with at least 4 years follow-up (n = 178). Slope correlated significantly with systolic blood pressure (r = 0.26 and 0.29) in both groups, diastolic blood pressure only in the 4-year group (r = 0.22) and average albuminuria in both (r = 0.31 and 0.24). By multiple regression analyses systolic blood pressure and average albuminuria remained with significant influence on slope. Progression was defined as an increase in the category (e.g. normo- to microalbuminuria) as well as an increase of more than 20% in albumin excretion, and was seen in 46 patients with at least 4 years' follow-up.(ABSTRACT TRUNCATED AT 250 WORDS)

Mortality in diabetic subjects: an eleven-year follow-up of a community-based population

In 1979, all the known diabetic subjects (849) were identified from a community (population 81851), of whom 717 (85%) were reviewed by a single observer. Using the NHS Central Register, follow-up was completed for 98% of subjects. After 11 years, 306 (42.7%) diabetic subjects had died, of whom 65 were insulin treated and 241 were non-insulin treated. Circulatory disease accounted for 168 (54.9%) deaths, of which 124 (73.8%) were due to ischaemic heart disease. The standardized mortality ratio (SMR) for all causes of death, based on data from England and Wales, was significantly raised for both insulin-treated and non-insulin-treated patients (1.75, 95% CI 1.35 to 2.24 and 1.32, 95% CI 1.15 to 1.50, respectively). SMRs for all cause mortality were significantly greater for diabetic subjects in the 45-64 (SMR, 1.97, 95% CI 1.34 to 2.80), 65-74 (SMR 1.59, 95% CI 1.27 to 1.97 and 75 years and over (SMR 1.26, 95% CI 1.08 to 1.45) age ranges. Using a proportional hazards model, after adjusting for age and gender, systolic blood pressure and vibration threshold were significant predictors of all cause mortality in insulin-treated subjects. For non-insulin-treated subjects, blood glucose, systolic blood pressure, glycated haemoglobin, retinopathy, proteinuria, coronary artery disease, and stroke were significant baseline predictors of mortality. No association was found for serum cholesterol, body mass index, diastolic pressure or cigarette smoking in either treatment group.

Alteration of oxide reductive and haemostatic factors in type 2 diabetics

OBJECTIVE

To assess any pathogenic role of radical activity and haemostatic alteration in the early cardiovascular disease of microalbuminuric type 2 diabetics (non-insulin dependent).

DESIGN

A selected cohort of type 2 diabetics was identified, divided according to urinary albumin excretion and compared with a healthy control group depending on some haemostatic factors and radical activity.

SETTING

All the subjects were studied as outpatients.

SUBJECTS

Eighty diabetics and 84 healthy controls were interviewed and underwent blood tests to exclude standard cardiovascular risk factors before follow up.

MAIN OUTCOME MEASURES

The subjects were males, age range 43-55 years, and divided according to albumin excretion (microalbuminuria > 30-200 mg L-1; normoalbuminuria < 15 mg L-1). The mean duration of diabetes referred by the patients was 9.3 years in albuminuric and 11.1 years in normoalbuminuric patients with a good control of plasma glucose level. Neither the diabetics nor the control group showed clinical evidence of renal and cardiovascular diseases.

RESULTS

Microalbuminuric patients presented elevated malondialdehyde concentration, glutathione peroxidase activity, phospholipidic fatty acid levels, fibrinogen, plasminogen activator inhibitor, tissue plasminogen activator and von Willebrand factor compared with normoalbuminuric patients and controls. More collagen was required in microalbuminuric diabetics than in normoalbuminurics and controls.

CONCLUSIONS

Our results confirm that both free radical activity and changes in haemostatic factors can be observed in type 2 diabetes and particularly in patients with albuminuria. Our very selected series with short duration, good control of diabetes and lack of clinical evidence of cardiovascular disease may suggest that these abnormalities develop earlier and may be associated with, and/or implicated in, the pathogenesis of microvascular complications which can be related to a higher and early cardiovascular morbidity and mortality rate in microalbuminuric diabetics.

Associations with retinopathy in type 2 diabetes: a population-based study in a Swedish rural area

This population-based study was carried out in a rural area in Sweden. The impact of duration of diabetes, metabolic control, albuminuria, and mode of detection (screening or presence of overt symptoms at the time of diagnosis) on retinopathy in patients with type 2 diabetes aged under 70 years was investigated at a primary health care centre. Ninety-nine percent of all known persons with Type 2 diabetes were under care at the centre. The fundi were examined in all but one of those under 70 years, and a 100% attendance rate was noted with regard to other variables such as albuminuria, glycated haemoglobin, and blood lipids. A team approach (general practitioner, nurse specialist, dietitian, and chiropodist) with patient education as an integral part of the treatment has been practised for the past 15 years. Retinopathy was associated with duration of disease, glycaemic control, systolic blood pressure, detection by overt symptoms, and albuminuria. The risk of retinopathy was not associated with smoking or treatment category. The prevalence of retinopathy was 26.5% in the whole population, and 18.8% among the patients who had been treated for their diabetes at the centre from the time of diagnosis. The importance of an appropriate organization in primary health care for early case finding, near-normal glycaemia, team approach, and structured collaboration with a department of ophthalmology is emphasized in order to realize the aims of the St Vincent declaration to reduce eye complications due to Type 2 diabetes.

Therapeutic progress. III: Diabetic nephropathy

Diabetic nephropathy is a common cause of end stage renal failure. Patients ultimately require dialysis or transplantation and endure a poor quality of life in association with increased mortality. Due to the quantitative significance of this problem there is also a considerable financial burden. It has been generally accepted that once nephropathy is established it is irreversible although aggressive anti-hypertensive treatment can delay its progression. More recently there have been numerous reports proposing a specific renal protective role of certain drugs. In this article we review the current literature on the use of angiotensin converting enzyme inhibitors in diabetic nephropathy. There is strong evidence that the use of ACE inhibitors in diabetic nephropathy (in the presence or absence of hypertension) slows the progression of deterioration in renal function and may even arrest its progression if detected at the microproteinuric stage.

Microalbuminuria: prognostic and therapeutic implications in diabetes mellitus

Thirty years following the development of the first radioimmunoassay for albumin, microalbuminuria is widely acknowledged as an important predictor of overt nephropathy in patients with Type 1 diabetes and of cardiovascular mortality in Type 2 diabetes. In addition, there is accumulating evidence to suggest that diabetic patients with microalbuminuria may have more advanced retinopathy, higher blood pressure, and worse dyslipidaemia than patients with normal albumin excretion rates. Recent studies have focused on the role of intervention, principally with antihypertensive therapy and intensive glycaemic control, in reducing microalbuminuria. While successful in reducing urinary albumin excretion it remains to be established whether such therapies will be translated into a reduction in renal failure and decreased cardiovascular morbidity and mortality.

Epidemiology of microalbuminuria in the general population

Microalbuminuria in the general population is associated with recognized risk factors for cardiovascular disease such as hypertension, hyperglycemia, hyperinsulinemia, and hyperlipidemia; and it is an independent predictor of subsequent cardiovascular mortality in hypertensive, diabetic, and elderly populations. Although different methods have been used for measuring and expressing urinary albumin excretion and a variety of cutoff levels have been used for defining microalbuminuria, prevalence of microalbuminuria appears to be higher in non-Europeans (8%-28%) than in Europeans (2%-10%). However, because of the large within-individual variability of urinary albumin excretion and the relatively low prevalence of microalbuminuria, large studies are required to detect statistically significant associations between albuminuria and cardiovascular risk factors. Evidence presented here supports the proposition that microalbuminuria represents a marker of cardiovascular disease risk in nondiabetic individuals as well as diabetic individuals. Moreover, because of a high sensitivity of the test and because albuminuria is a concomitant of many forms of renal disease, microalbuminuria also has a role in detecting patients with renal involvement associated with essential hypertension, lupus erythematosus, women with pre-eclampsia, and subjects with unsuspected primary and secondary nephropathies.

Microalbuminuria: pathogenesis, prognosis and management

The development in recent years of sensitive assays specific for albumin has facilitated extensive investigation of the pathophysiology and clinical significance of microalbuminuria. It is now clear that the appearance of microalbuminuria represents a crucial event in the natural histories of diabetes mellitus and essential hypertension. It reflects the presence of generalized vascular damage and is strongly predictive of subsequent renal failure, cardiovascular morbidity, and death. Therapeutic interventions, including strict diabetic and blood-pressure control, can reduce microalbuminuria and improve the overall prognosis. The detection and treatment of microalbuminuria in these high-risk groups should now form an integral part of their management. Large-scale screening programmes are also recommended for insulin-dependent diabetics.

Associations of urinary albumin excretion rate with vascular disease in europid nondiabetic subjects

Microalbuminuria and its association with vascular disease has previously been reported in nondiabetic individuals. The aims of this study were to determine whether there is a cross-sectional relationship between urinary albumin excretion rate and cardiovascular disease in nondiabetic subjects and to investigate hereditary predisposition to microalbuminuria by studying offspring of the main study population. Europid patients, aged 40-70 years, were randomly selected from a large inner-city general practice; there was a 62.6% attendance rate, and a study population of 959 remained after exclusions. Blood pressure, ankle systolic pressure, height, and weight were measured. Albumin excretion rate was calculated from overnight and morning urine collections. Venous blood was taken for lipids, fibrinogen, and factor VII; and resting electrocardiograms were carried out. Offspring (aged 15-40 years) of those found to be microalbuminuric were invited to attend for the same tests, and controls were selected by age and sex matching the parents. There was no association between parents' albumin excretion rate with that of their offspring, and there were no significant differences in albumin excretion rate between offspring subjects and their controls. There were no statistically significant associations of prevalent coronary heart disease (CHD) with albumin excretion rate or microalbuminuria in either sex [CHD in women: odds ratio (OR) 1.85; 95% confidence interval (CI) 0.19,9.0] [CHD in men: OR 2.13; 95% CI (0.64, 6.59)]. In women, there were significant associations between albumin excretion rate and peripheral vascular disease (positive) and fibrinogen (negative). Because established risk factors may not be as strongly associated with CHD in cross-sectional studies, we intend to follow this group prospectively.

Cost-effectiveness of screening for microalbuminuria using immunochemical dipstick tests or laboratory assays in diabetic patients

To analyse the cost-effectiveness ratio of screening for microalbuminuria in diabetic patients using either dipstick tests or laboratory assays, 506 diabetic patients were screened for microalbuminuria using both a traditional laboratory assay (strategy I) or a laboratory assay only in the case of a positive dipstick result (strategy II). Dipstick pre-screening was considered positive if at least one of the tests performed by the two different operators showed an albumin excretion rate > 20 micrograms min-1. It was performed using a new dipstick, Micral-Test, designed to distinguish low albumin concentrations. Biological assay was the reference method. Costs were related to laboratory assays (strategy I) or to dipstick tests and laboratory assays for positive results (strategy II). The loss of effectiveness was related to false negative results of strategy II. The double dipstick pre-screening showed a sensitivity of 90.8% and a specificity of 80.1%. Its predictive value was 97% for a negative result and 55.6% for a positive result. False positive results were associated with elevated urinary volumes. Compared with strategy I, strategy II showed a sensitivity of 90.8%, a specificity of 100%, and predictive values of 100% and 97.5%, respectively, for positive and negative results. In a fictitious cohort of 10,000 patients, strategy II yielded a gain of 16,750 pounds on the first year, which decreased to 5345 pounds after 30 years. The loss in effectiveness was estimated at 2.38 quality adjusted life years of a diabetic patient (QALYd) initially, and decreased to 0.91 QALYd after 30 years, the annual cost-effectiveness ratio being close to 6600 pounds QALYd-1.(ABSTRACT TRUNCATED AT 250 WORDS)

Insulin treatment improves microalbuminuria and other cardiovascular risk factors in patients with type 2 diabetes mellitus

OBJECTIVES

Insulin treatment of patients with type 2 diabetes causes hyperinsulinaemia and improves glycaemic control. We have studied how this affects risk factors for cardiovascular disease.

DESIGN

Patients with secondary failure to oral hypoglycaemic agents were studied whilst still taking oral agents and after insulin treatment for 8 weeks in an open study.

SETTING

Department of Internal Medicine, University Hospital, Linköping.

SUBJECTS

Ten consecutive patients with type 2 diabetes and secondary failure to oral hypoglycaemic agents.

INTERVENTIONS

Switching oral treatment to insulin treatment.

MAIN OUTCOME MEASURES

Effect on several cardiovascular risk factors.

RESULTS

Fasting and postprandial plasma insulin concentrations were increased by insulin treatment whereas C-peptide concentrations were lowered. HbA1c was reduced from 8.9 +/- 0.3% (mean +/- SEM) to 6.3 +/- 0.2% after 8 weeks. There was a weight gain of 2.8 +/- 0.7 kg. Plasma concentrations of total- and very-low-density-lipoprotein (VLDL) cholesterol, VLDL-, low density lipoprotein and high-density-lipoprotein triglycerides were all reduced. The plasma concentration of apolipoprotein B was also lowered. Tissue plasminogen activator antigen measured after venous occlusion showed a significant reduction whilst plasminogen activator inhibitor 1 activity was 26.0 +/- 9.8 IU ml-1 on oral treatment and 18.2 +/- 4.7 IU ml-1 on insulin treatment (NS). Albumin excretion in the urine was reduced and the percentage reduction correlated with the percentage lowering of the tissue plasminogen activator antigen concentration after venous occlusion but not with the percentage change of basal tissue plasminogen activator antigen concentration.

CONCLUSIONS

Insulin treatment of patients with type 2 diabetes and secondary failure to oral hypoglycaemic agents causes hyperinsulinaemia and improves or has no unfavourable effect on several cardiovascular risk factors.

Microalbuminuria in type 2 diabetic patients: a cross-sectional study of frequency, sex distribution and relation to hypertension

We studied 112 type 2 diabetic patients. Fourteen patients had frank proteinuria, and 37 of the remaining 98 had microalbuminuria which was more frequent in men than in women (P < 0.02). Hypertension was found in 47 of the patients, equally distributed between sexes. Male diabetics with microalbuminuria had higher systolic blood pressure than diabetics without microalbuminuria (P < 0.02). Body mass index was higher in both sexes with hypertension compared to patients without hypertension. In the hypertensive men plasma C-peptide values were higher compared to patients without hypertension (P < 0.01) irrespective of the presence of microalbuminuria. A positive correlation between blood pressure and C-peptide was found (P < 0.01) in the men. We suggest that gender should be taken into account in the analysis and interpretation of microalbuminuria in type 2 diabetes.

Glomerular filtration rate in Indian non-insulin-dependent diabetics at various stages of albuminuria

Sixty-seven non-insulin-dependent diabetic subjects were selected to estimate the glomerular filtration rate (GFR). All patients had satisfactory glycaemic control (HbA1 < 9.5%). GFR was determined using Technetium 99m DTPA by the method devised by Gates. Thirty-eight subjects had normal albumin excretion (UAE < 20 micrograms/min), 15 had UAE in the microalbuminuric range (20-100 micrograms/min), and the rest were macroalbuminuric (> 200 micrograms/min). GFR was lower in the normoalbuminuric patients as compared to the controls, but the decrease was not significant (71.5 (21.4) vs. 98.3 (16.1) ml/min per 1.73 m2. GFR was significantly decreased in both micro and macroalbuminuric groups (64.0 (24.5) and 53.8 (27.3) ml/min per 1.73 m2, respectively) (P < 0.05). No appreciable change in GFR was observed in normoalbuminuric patients with increasing duration of diabetes, however, there was a steady decline in GFR with time in both micro- and macroalbuminuric patients. Hypertension was present in 79%, 47% and 16% of macro-, micro- and normoalbuminuric patients, respectively. GFR was significantly lower in hypertensive diabetic patients compared to normotensives (52.3 vs. 76.1 ml/min per 1.73 m2) (P < 0.01), while this difference was not significant in the micro- and macroalbuminuric groups. We conclude from our study that the stage of hyperfiltration could not be detected in non-insulin-dependent diabetes and that hypertension has a significant influence on the rate of decline of GFR.

The relationship between early diabetic nephropathy and control of plasma glucose in non-insulin-dependent diabetes mellitus. The effect of glycemic control on the development and progression of diabetic nephropathy in an 8-year follow-up study

To clarify the relationship between early diabetic nephropathy and the glycemic control in non-insulin-dependent diabetes mellitus (NIDDM) without hypertension, excretion of urinary albumin was studied retrospectively for 8 years. The patients with early diabetic nephropathy were divided into two groups according to the initial urinary albumin index (UAI: mg/g.creatinine), namely, a normoalbuminuric (less than 15 mg/g.creatinine) and a microalbuminuric group (15 < or = UAI < 200 mg/g.creatinine). Comparisons of changes in UAI were made between good (HbA1 < 9.0% and fasting plasma glucose (FPG) < 140 mg/100 mL throughout the observation period) and poor glycemic control groups after 4 and 8 years. In the patients with normoalbuminuria at the initial determination, five of 11 patients (45.5%) with good glycemic control and 14 of 22 patients (63.6%) with poor glycemic control became microalbuminuric after 8 years, respectively (p < 0.05). In the microalbuminuric patients, five of ten patients (50%) with poor glycemic control became macroalbuminuric (UAI > or = 200 mg/g.creatinine), although only one case worsened of five patients with good glycemic control (p < 0.05). In conclusion, the development or progression of early diabetic nephropathy in NIDDM was significantly inhibited by good glycemic control (FPG < 140 mg/100 mL and HbA1 < 9.0%), independent of hypertension, and probably irrespective of the mode of therapeutic intervention.

Insulin resistance is related to albuminuria in patients with type II (non-insulin-dependent) diabetes mellitus

To determine whether albuminuria is associated with insulin resistance in patients with type II (non-insulin-dependent) diabetes mellitus, we performed hyperinsulinemic (40 mU/m2/min) euglycemic clamp studies in patients with a urinary albumin excretion (UAE) rate greater than 30 mg/24 h and in patients with a UAE less than 30 mg/24 h. The UAE-positive group (n = 22) did not differ significantly from the UAE-negative group (n = 18) with respect to age, sex, treatment of diabetes, body mass index, fasting or postload blood glucose or plasma insulin levels, blood pressure, or known duration of diabetes. The mean glucose disposal rate (GDR) was significantly lower in the UAE-positive group than in the UAE-negative group (3.44 +/- 0.29 v 4.75 +/- 0.52 mg/kg/min, P < .05). When patients with hypertension were excluded, GDR was still markedly lower in the UAE-positive group than in the UAE-negative group (3.89 +/- 0.54 v 6.68 +/- 0.71 mg/kg/min, P = .01). The difference between groups persisted even after adjustment for body mass index, sex, and hypertension (ANCOVA; P < .05). These results indicate that the presence of microalbuminuria is associated with impaired insulin action in patients with type II diabetes mellitus.

Urinary albumin excretion in a population based sample of 1011 middle aged non-diabetic subjects. The Copenhagen City Heart Study Group

Increased urinary albumin excretion rate (UAER) especially in the range of 20-200 micrograms min-1, termed microalbuminuria, has been proposed as a risk marker and predictor for cardiovascular disease in non-diabetic subjects. Thus it would be of importance to describe the distribution of UAER in the non-diabetic population. Among 1011 30-70-year-old subjects without diabetes mellitus or urinary tract infection, who were invited to participate in a population based epidemiological study, the albumin concentration was measured in an overnight urine sample. The measurement was performed by an ELISA method. The UAER was calculated in units of micrograms min-1 as urinary albumin concentration x urine volume/urine collection time. The distribution of UAER was positively skewed with a median value of 2.3 micrograms min-1 and a 5-95 interpercentile range of 0-11.0 micrograms min-1. The UAER held constant with age, but males had higher UAER than females, 2.6 (0-13.5) micrograms min-1 vs 2.2 (0-8.3) micrograms min-1; p < 0.005. The prevalence of microalbuminuria, defined as an UAER in the range of 15-150 micrograms min-1 in an overnight urine sample, was 3% (95% C.I. interval: 1.9-4.0). These findings suggest, that the level of UAER which might notify increased cardiovascular risk, is lower than in patients with diabetes mellitus, if it is considered to be of any clinical relevance.

Epidemiology of renal involvement in newly-diagnosed middle-aged and elderly diabetic patients. Cross-sectional data from the population-based study "Diabetes Care in General Practice", Denmark

We report on a study in which 487 Danish general practitioners participated with the purpose of including all newly-diagnosed diabetic patients aged 40 years or more from a well-defined catchment population during a well-defined time period. A total of 1267 diabetic patients with a median age of 65.3 years were included. Renal involvement was assessed from the albumin/creatinine ratio in a morning urine sample. Albumin/creatinine ratio was < 2/2- < 20/ > or = 20 mg/mmol in 59.8/33.6/6.6% of male and 66.6/28.8/4.6% of female patients. The level of albumin/creatinine ratio increased with age and the observed overall male predominance was almost confined to diabetic patients with an albumin/creatinine ratio of 5 mg/mmol or greater. By taking into account the confounding effect of age and sex, a positive association between smoking and albumin/creatinine ratio was disclosed. Moreover, high systolic blood pressure, hypertriglyceridaemia, hypercholesterolaemia (males only) and high HbA1c, but not body mass index or diastolic blood pressure were identified as correlates of elevated albumin/creatinine ratio. Glucosuria was positively correlated with albumin/creatinine ratio even when the influence of HbA1c, sex and age was taken into account. A positive correlation between serum creatinine and albumin/creatinine ratio was seen in males, but not in females. In addition, renal involvement was associated with the presence of peripheral angiopathy and diabetic retinopathy and with high resting heart rate. The cross-sectional data presented highlight the importance of reducing the overall burden of modifiable risk factors in newly-diagnosed Type 2 diabetic patients.

Glomerular structure and function in proteinuric type 2 (non-insulin-dependent) diabetic patients

Glomerular ultrastructure was examined in a series of 20 Type 2 (non-insulin-dependent) diabetic patients with proteinuria. Reference was made to data previously obtained in non-diabetic kidney donors and in Type 1 (insulin-dependent) diabetic patients with similar degrees of proteinuria. The Type 2 diabetic patients demonstrated the changes which characterize the diabetic glomerulopathy seen in Type 1 diabetic patients: basement membrane thickening, and increase in the mesangium and mesangial matrix expressed as fraction of the glomerular volume. Among the Type 2 diabetic patients there was more variation than among the Type 1 diabetic patients, as this group included subjects with normal parameters. The group means and coefficients of variation (= SD/mean) of the glomerulopathy parameters combined in the glomerulopathy index = basement membrane thickness/10+ Vv(matrix/glom).100 were 81 (0.30) and 92 (0.15) in the two diabetic groups, clearly different from the non-diabetic index, 42 (0.16). All Type 2 diabetic patients who also had retinopathy had a glomerulopathy index above the normal range. Similar changes in glomerular composition were seen in the two diabetic groups: with increasing glomerulopathy the volume of matrix dominated over the peripheral basement membrane, and a shift in the ratio of interfaces was seen: mesangial surface towards capillary lumen increased relative to the urinary surface, and peripheral capillary surface comprised less of the total capillary surface. Data indicated marked glomerular hypertrophy, which correlated with the mesangial volume fraction, thus encompassing preserved filtration surface per glomerulus.(ABSTRACT TRUNCATED AT 250 WORDS)

Relationship between insulin resistance and coronary heart disease in diabetes mellitus and the general population: a critical appraisal

The hypothesis that a causal relationship exists between insulin resistance and atherogenesis was first proposed over 23 years ago, and has given rise to a vast literature. Biological plausibility has been lent to the hypothesis by studies in which insulin has produced some effects in cell and tissue culture, and in vivo in arterial tissue, consistent with our understanding of the pathogenesis of atherosclerosis. Clinical studies demonstrating a complex interrelationship between insulin resistance-hyperinsulinaemia and established risk factors for CHD--hypertension, hypertriglyceridaemia, low HDL cholesterol levels and abdominal obesity--are reviewed. A review of the studies examining an independent association between hyperinsulinaemia and coronary heart disease is presented. Cross-sectional studies in both the general population and diabetes support the relationship; however, prospective studies in the general population provide limited and inconsistent support for this hypothesis and highlight the confounding effects of blood pressure, dyslipidaemia and obesity on the effects of hyperinsulinaemia. In subjects with NIDDM and impaired glucose tolerance, prospective studies have not shown a deleterious effect of insulin treatment per se, nor have they consistently shown a significantly increased risk for those with higher endogenous insulin levels. The therapeutic implications of the evidence to date are less complex and involve weight reduction by diet and exercise, the lowering of elevated blood pressure with metabolically neutral agents, the judicious use of lipid lowering drugs and, in diabetes, the use of insulin where clinically indicated.

Is microalbuminuria part of the prediabetic state? The Mexico City Diabetes Study

Microalbuminuria is associated with increased cardiovascular mortality in both diabetic and non-diabetic subjects. A number of studies have indicated that insulin resistance, increased blood pressure and dyslipidaemia precede the onset of clinical diabetes. We examined various correlates of microalbuminuria in 1,298 non-diabetic subjects who participated in the Mexico City Diabetes Study, a population-based study of diabetes and cardiovascular risk factors. Both parental history of diabetes and impaired glucose tolerance were significantly associated with microalbuminuria. These results were not explained by differences in age or blood pressure between subjects with or without a parental history of diabetes or impaired glucose tolerance. In addition, subjects with microalbuminuria had increased 2-h insulin and triglyceride concentrations, a higher prevalence of hypertension, and decreased high density lipoprotein cholesterol concentrations relative to subjects without microalbuminuria. These results that microalbuminuria may be a feature of the prediabetic state.

Microalbuminuria in a random cohort of recently diagnosed type 2 (non-insulin-dependent) diabetic patients living in the greater Munich area

Still under debate is the prevalence of microalbuminuria in patients with recently diagnosed Type 2 (non-insulin-dependent) diabetes mellitus and its relation to existing macro-vascular disease and the major vascular risk markers. Hence, from a representative sample of 1512 patients with Type 2 diabetes of varied duration (recruited from 22 non-specialized medical practices of the Greater Munich Area) 68 (26 males, 42 females) of 71 eligible subjects with a known duration of diabetes of up to 17 weeks and not less than 4 weeks were examined in the present study. Median age was 61 (39 to 75) years, prevalence of ischaemic heart disease (case history plus ECG, Minnesota code, Whitehall criteria) 41.2%, and that of peripheral vascular and carotid artery disease (both assessed by ultrasound-Doppler) were 35.3 and 4.4%, respectively. Diabetes was well controlled (HbA1c: 6.9%, 5.6-8.3; fasting blood glucose: 7.7 mmol/l, 5.4-10.4; median +/- interquartile range IQ), the cardiovascular risk profile was most prominent in terms of triglycerides (3.1 mmol/l, 2.1-4.6, median +/- IQ range) and systolic blood pressure (164 mm Hg, 140-186, median +/- IQ range). 13.2% showed signs of urinary tract infection. Of the remainder, 19.0% exhibited microalbuminuria (RIA, > 30-200 mg/l), and 5.2% macroalbuminuria (> 200 mg/l). Significant correlations (p < 0.05) were found between urinary albumin concentration and beta 2-microglobulin in serum, systolic blood pressure, serum triglycerides, serum HDL-cholesterol (inversely), HbA1c, and peripheral vascular disease.(ABSTRACT TRUNCATED AT 250 WORDS)

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

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

Prognostic value of urinary albumin excretion rate and other risk factors in elderly diabetic patients and non-diabetic control subjects surviving the first 5 years after assessment

In 1981-1982 urinary albumin excretion rates were determined in 211 diabetic and 216 non-diabetic subjects aged 60-74 years. By April 1992 122 diabetic and 58 non-diabetic probands had died. Dividing the two study populations at an albumin excretion rate of 15 micrograms/min showed that 69.3% of diabetic subjects with values at or above the limit, and 49.9% of those with values below (log rank test p = 0.0082) had died. The corresponding values for non-diabetic subjects were 44.4% and 21.0%, respectively (log rank test p = 0.0002). In single factor log rank tests ischaemic heart disease and a low value of HDL were also predictive of death in the diabetic population during a 10-11-year observation period. In the non-diabetic population ischaemic heart disease, hypertension, and a serum creatinine level above the median value were predictive. In further log rank analyses probands dying during the first years, (e.g. the first 2 years) were removed from the calculations. The prognostic value of the above-mentioned factors diminished with time. In a Cox Regression analysis we found that the predictive value of urinary albumin excretion rate to mortality had disappeared when subjects who had died during the first 5 years were removed from the analysis, whereas HDL in the diabetic patients and blood pressure and serum creatinine in non-diabetic subjects were still of significant predictive value. We therefore conclude that urinary albumin excretion rate is a more short-term predictor of mortality than previously thought, in contrast to HDL, hypertension and serum creatinine.

Renal function and insulin sensitivity during simvastatin treatment in type 2 (non-insulin-dependent) diabetic patients with microalbuminuria

The effect of simvastatin (10-20 mg/day) on kidney function, urinary albumin excretion rate and insulin sensitivity was evaluated in 18 Type 2 (non-insulin-dependent) diabetic patients with microalbuminuria and moderate hypercholesterolaemia (total cholesterol > or = 5.5 mmol.l-1). In a double-blind, randomized and placebo-controlled design treatment with simvastatin (n = 8) for 36 weeks significantly reduced total cholesterol (6.7 +/- 0.3 vs 5.1 mmol.l-1 (p < 0.01)), LDL-cholesterol (4.4 +/- 0.3 vs 2.9 +/- 0.2 mmol.l-1 (p < 0.01)) and apolipoprotein B (1.05 +/- 0.04 vs 0.77 +/- 0.02 mmol.l-1 (p < 0.01)) levels as compared to placebo (n = 10). Both glomerular filtration rate (mean +/- SEM) (simvastatin: 96.6 +/- 8.0 vs 96.0 +/- 5.7 ml.min-1 x 1.73 m-2, placebo: 97.1 +/- 6.7 vs 88.8 +/- 6.0 ml.min-1 x 1.73 m-2)(NS) and urinary albumin excretion rate (geometric mean x/divided by antilog SEM) (simvastatin: 18.4 x/divided by 1.3 vs 16.2 x/divided by 1.2 microgram.min-1, placebo 33.1 x/divided by 1.3 vs 42.7 x/divided by 1.3 micrograms.min-1)(NS) were unchanged during the study. A euglycaemic hyperinsulinaemic clamp was performed at baseline and after 18 weeks in seven simvastatin- and nine placebo-treated patients. Isotopically determined basal and insulin-stimulated glucose disposal was similarly reduced before and during therapy in both the simvastatin (2.0 +/- 0.1 vs 1.9 +/- 0.1 (NS) and 3.1 +/- 0.6 vs 3.1 +/- 0.7 mg.kg-1 x min-1 (NS)) and the placebo group (1.9 +/- 0.1 vs 1.8 +/- 0.1 (NS) and 4.1 +/- 0.6 vs 3.8 +/- 0.2 mg.kg-1 x min-1 (NS)).(ABSTRACT TRUNCATED AT 250 WORDS)

Determinants of end-stage renal disease in Pima Indians with type 2 (non-insulin-dependent) diabetes mellitus and proteinuria

To identify factors related to the development of end-stage renal disease after the onset of proteinuria, its incidence was determined in 364 Pima Indians aged 35 years or older with Type 2 (non-insulin-dependent) diabetes mellitus and proteinuria (protein-to-creatinine ratio > or = 0.5 g/g). Of these 364 subjects, 95 (36 men, 59 women) developed end-stage renal disease. The cumulative incidence was 40% 10 years after and 61% 15 years after the onset of proteinuria. The incidence of end-stage renal disease was significantly related to the duration of diabetes, the duration of proteinuria, higher 2-h plasma glucose concentration, type of diabetes treatment, and the presence of retinopathy at the time of recognition of the proteinuria, but not to age, sex, or blood pressure. Duration of proteinuria influenced the risk of end-stage renal disease, contingent, however, upon the duration of diabetes at the onset of proteinuria. The higher cumulative incidence of end-stage renal disease 15 years after the onset of proteinuria in Pima Indians (61%) than in Caucasians from Rochester, Minnesota (17%) may be attributable, in part, to the younger age of onset of Type 2 diabetes in Pima Indians than in Caucasians, to ethnic differences in susceptibility to renal disease, or to lower death rates among the Pima Indians from competing causes of death, such as coronary heart disease.

The effect of microalbuminuria on glycaemic control, serum lipids and haemostasis parameters in non-insulin-dependent diabetes mellitus

Microalbuminuria is an important risk factor for cardiovascular disease in non-insulin-dependent diabetes mellitus (NIDDM) patients although the pathogenic mechanism between microalbuminuria and cardiovascular disease has not yet been established. Microalbuminuria in insulin-dependent diabetes mellitus (IDDM) patients has been related to abnormalities in haemostasis, poor glycaemic control, disadvantageous alterations in the lipid spectrum and elevated concentrations of lipoprotein(a), another independent risk factor for cardiovascular disease. In this study the interrelations between microalbuminuria and metabolic control, lipoprotein(a), other blood lipids and several haemostasis parameters were studied in 96 NIDDM patients (50 women, 46 men). Forty-three patients showed microalbuminuria. No significant differences were found in blood lipids (Lp(a), serum cholesterol, low-density lipoprotein and high-density lipoprotein cholesterol and triglycerides), glycaemic control (HbA1c) and several haemostasis parameters (factor VII, VIII, fibrin monomer, thrombin-antithrombin III, D-dimer, tissue plasminogen activator antigen and plasminogen activator inhibitor-1) between the micro- and normoalbuminuric subgroups. In the microalbuminuric subgroup increased concentrations for plasminogen and alpha 2-antiplasmin were measured. In general, the presence of microalbuminuria was not associated with significant alterations in glycaemic control, blood lipids or haemostasis parameters in this group of 96 NIDDM patients. Further investigation is required to explain the excess cardiovascular mortality in patients with an elevated urinary albumin excretion rate.

Inhibition of angiotensin-converting enzyme reduces urinary albumin excretion but not regional albumin clearance in experimental diabetes

Albuminuria and increased regional albumin clearance are known to develop concomitantly in diabetes. The anti-proteinuric effect of angiotensin-converting enzyme inhibitor therapy is well established. We studied whether angiotensin-converting enzyme inhibitor therapy with perindoprilat in comparison with conventional antihypertensive treatment could influence the development of increased regional albumin clearance as well as albuminuria in experimental diabetes. Rats with streptozotocin-induced diabetes were randomized into a saline group (n = 7), a perindoprilat (1 mg/kg per day) group (n = 8), and a hydralazine (3 mg/kg per day) group (n = 6); six rats served as non-diabetic controls. After 6-8 weeks, blood pressure was equally reduced in the perindoprilat- and hydralazine-treated groups (P < 0.01). Twenty-four-hour urinary protein and albumin excretion were increased in diabetic rats compared to control rats (P < 0.001). Hydralazine did not reduce 24 h protein or albumin excretion, whereas perindoprilat treatment reduced both (P < 0.001) to levels comparable to those of control rats. Regional albumin clearance, assessed in the eye, ileum, lung, skeletal muscle and skin, was clearly elevated in diabetic rats compared to control rats; however, neither drug therapy had an effect on albumin clearance.

A prospective study of clinical and metabolic associates of proteinuria in patients with type 2 diabetes mellitus

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

Insulin resistance, hypertension and microalbuminuria in patients with type 2 (non-insulin-dependent) diabetes mellitus

We examined the impact of hypertension and microalbuminuria on insulin sensitivity in patients with Type 2 (non-insulin-dependent) diabetes mellitus using the euglycaemic insulin clamp technique in 52 Type 2 diabetic patients and in 19 healthy control subjects. Twenty-five diabetic patients had hypertension and 19 had microalbuminuria. Hypertension per se was associated with a 27% reduction in the rate of total glucose metabolism and a 40% reduction in the rate of non-oxidative glucose metabolism compared with normotensive Type 2 diabetic patients (both p < 0.001). Glucose metabolism was also impaired in normotensive microalbuminuric patients compared with normotensive normoalbuminuric patients (29.4 +/- 2.2 vs 40.5 +/- 2.8 mumol.kg lean body mass-1.min-1; p = 0.012), primarily due to a reduction in non-oxidative glucose metabolism (12.7 +/- 2.9 vs 21.1 +/- 2.6 mumol.kg lean body mass-1.min-1; p = 0.06). In a factorial ANOVA design, however, only hypertension (p = 0.008) and the combination of hypertension and microalbuminuria (p = 0.030) were significantly associated with the rate of glucose metabolism. The highest triglyceride and lowest HDL cholesterol concentrations were observed in Type 2 diabetic patients with both hypertension and microalbuminuria. Of note, glucose metabolism was indistinguishable from that in control subjects in Type 2 diabetic patients without hypertension and microalbuminuria (40.5 +/- 2.8 vs 44.4 +/- 2.8 mumol.kg lean body mass-1.min-1). We conclude that insulin resistance in Type 2 diabetes is predominantly associated with either hypertension or microalbuminuria or with both.

Microalbuminuria in essential hypertension. Reduction by different antihypertensive drugs

The effects of four different antihypertensive drugs (the Ca(2+)-channel blocker felodipine, the beta-blocker metoprolol, the angiotensin converting enzyme inhibitor ramipril, and the alpha-blocking agent doxazosin) on microalbuminuria and renal hemodynamics were evaluated in a double-blind, crossover study in 17 patients (10 women, seven men, aged 39 +/- 14 years) with mild-to-moderate essential arterial hypertension and microalbuminuria. Patients were studied after a 2-week placebo phase preceded by 2 weeks off all medication and after 12 weeks of treatment with each drug. Between each drug treatment, there was another 14-day placebo washout period. At the end of the study, we performed two additional 2-week placebo periods. After each placebo and treatment period, we measured albumin excretion during a 3-day collecting period. Renal hemodynamics were assessed by clearance techniques (inulin and p-aminohippurate clearance) at the end of the first and last placebo periods and after each treatment period. All drugs reduced mean arterial pressure and microalbuminuria to a similar and statistically significant (p < 0.05) extent (mean arterial pressure: placebo phase, 116 +/- 5 mm Hg; felodipine, 101 +/- 4 mm Hg; metoprolol, 101 +/- 5 mm Hg; ramipril, 101 +/- 4 mm Hg; doxazosin, 102 +/- 5 mm Hg; urinary albumin excretion: placebo phase, 46 +/- 50 mg/day; felodipine, 18 +/- 23 mg/day; metoprolol, 14 +/- 12 mg/day; ramipril, 16 +/- 16 mg/day; doxazosin, 14 +/- 14 mg/day). Mean arterial pressure levels and urinary albumin excretion returned to baseline after the last placebo period (110 +/- 6 mm Hg and 40 +/- 46 mg/day, respectively).(ABSTRACT TRUNCATED AT 250 WORDS)

Captopril or conventional therapy in hypertensive type II diabetics. Three-year analysis

The effects of long-term treatment with captopril and conventional therapy on albuminuria and metabolic parameters were compared in 74 hypertensive type II diabetics with normal serum creatinine. Patients were treated double-blind with either captopril monotherapy or combined with hydrochlorothiazide or therapy with metoprolol, hydrochlorothiazide, or both for 36 months. The treatment was titrated to achieve goal diastolic blood pressure of < or = 85 mm Hg. The reductions in blood pressures during treatment were similar in patients with (n = 21) and without (n = 53) microalbuminuria treated with either captopril or conventional therapy. No significant changes in albuminuria occurred in normoalbuminuric patients with either therapy. Although albuminuria fell in nearly all patients with microalbuminuria treated with captopril, it rose in eight of 12 patients on conventional therapy, with macroalbuminuria developing in two of them. Renal function was preserved by both types of treatment in both patient groups. Long-term treatment with either conventional therapy or captopril did not alter metabolic variables. We conclude that captopril alone or in combination decreases albuminuria and prevents the development of macroalbuminuria in hypertensive type II diabetics with persistent microalbuminuria. The renoprotective effect of this agent, however, remains to be demonstrated with longer term data on renal function. Aggressive antihypertensive treatment with either captopril or conventional therapy appears to be effective in preventing the onset of microalbuminuria in most normoalbuminuric patients. In contrast, with previous short-term studies, the use of converting enzyme inhibitors or conventional therapy did not cause adverse metabolic effects.

The value of screening for retinopathy and microalbuminuria in patients with type 2 diabetes in primary health care

Patients with type 2 diabetes (NIDDM) attending the Primary Care Centre in Mölnlycke, Sweden, were evaluated regarding their metabolic status, microalbuminuria (UAER), and hypertension. An ophthalmological examination was performed, and two diagnostic methods, slit-lamp biomicroscopy and fundus photography, were compared. Nearly half the patients (42%) had diabetic retinopathy, mainly of the background type. Retinopathy was associated only with the duration of the disease, but the prevalence was as high as 20% within 0-4 years of the diagnosis. Fundus photography was easy to apply, except in the age groups above 80 years, in otherwise healthy and mentally cooperative patients. Fundus photography could not be applied in only 7% of the patients for ophthalmological reasons. The prevalence of microalbuminuria (20-200 micrograms/min) was high--34%--with another 8% above that range. Male sex, mode of antidiabetic treatment, and hypertension were associated with an increased UAER. Screening for retinopathy and microalbuminuria is valuable in primary health care in order to detect treatable diabetic retinopathy and to trace patients with microalbuminuria, a risk factor for clinically overt nephropathy as well as for cardiovascular diseases.