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Ron T Gansevoort

Publications and source records attributed to Ron T Gansevoort.

28 records · Page 2Linked to original sources

Electrocardiographic abnormalities and uremic cardiomyopathy.

BACKGROUND: Progressive renal disease is associated with an increased risk of cardiovascular death, specifically sudden death. We investigated the link between uremic cardiomyopathy, QT interval and dispersal, and arrhythmias (by ambulatory ECG monitoring) in patients at different stages of progressive renal disease. METHODS: In a cross-sectional study we investigated 296 patients with nondiabetic renal disease (53 transplant recipients, 55 hemodialysis patients, and 188 throughout the range of chronic renal failure). Patients underwent echocardiography, ECG, and ambulatory blood pressure and ECG monitoring. RESULTS: Left ventricular mass was increased from the earliest stages of renal disease (near-normal renal function), the predominant pattern being eccentric left ventricular hypertrophy (LVH). There was a progressive increase in LVH with loss of renal function, so that more than 80% of patients on renal replacement therapy have LVH, the dominant pattern being concentric LVH. The prevalence of diastolic dysfunction increased in parallel with changes in left ventricular mass but systolic dysfunction and ventricular dilatation did not. Increased QT interval and QT dispersal were associated with poor renal function (maximal in dialysis patients), and were linked to LVH and other echocardiographic abnormalities. Arrhythmias were uncommon on ambulatory recording but were more common with poor renal function, in the presence of uremic cardiomyopathy, and increased QT interval and dispersal. CONCLUSION: LVH is present from the earliest stages of progressive renal disease. This, and other forms of uremic cardiomyopathy, is linked to increased QT interval and dispersal, and with minor rhythm abnormalities, providing a link with the high risk of sudden death in this population.

Adult↗

The association between atherosclerotic risk factors and renal function in the general population.

BACKGROUND: Generalized atherosclerosis is increasingly recognized as an important cause of end-stage renal disease (ESRD). We questioned to what extent atherosclerotic risk factors determine renal function in the general population. METHODS: We used baseline data of the Prevention of Renal and Vascular End-Stage Disease (PREVEND) Study. A total of 8592 subjects, aged 28 to 75 years old, visited the outpatient clinic for blood pressure and anthropometric measurements, fasting blood sampling, and delivery of two 24-hour urine collections for creatinine clearance and albuminuria calculations. Design-based multivariate linear regression was used to estimate renal function. RESULTS: In a multivariate model, male gender and body mass index (BMI) were associated with a higher renal function, while increasing diastolic blood pressure, serum triglycerides, use of antihypertensive or lipid-lowering medication were associated with a lower renal function. Age, systolic blood pressure, and plasma glucose showed an inverse U-shaped relationship with renal function. Cholesterol/high-density lipoprotein (HDL) ratio, smoking, and antidiabetic medication did not contribute to explain renal function. The atherosclerotic risk factors were related to renal function independently of albuminuria or C-reactive protein (CRP). Albuminuria and CRP itself were also related to renal function. Following gender and age, BMI, urinary albumin excretion (UAE), and plasma glucose had the strongest relation with renal function. CONCLUSION: We conclude that differences in renal function in the general population are (partly) explained by various atherosclerotic risk factors. Some risk factors are associated with elevated filtration, some with an impaired filtration, and others with both a higher and a lower renal function.

Adult↗

The validity of screening based on spot morning urine samples to detect subjects with microalbuminuria in the general population.

BACKGROUND: No study has yet investigated the validity of prescreening by albumin measurements in a spot morning urine sample to identify in the general population subjects with microalbuminuria. We therefore tested the diagnostic performance of urinary albumin concentration (UAC) and albumin-creatinine ratio (ACR), measured in a spot morning urine sample, in predicting a urinary albumin excretion (UAE) > or =30 mg in subsequent 24-hour urines (microalbuminuria). METHODS: Subjects (2527) participating in the PREVEND study, a representative sample from the general population, collected a spot morning urine sample and, on average, 77 days later, two 24-hour urine collections. RESULTS: The ROC curve of UAC in predicting microalbuminuria has an area-under-the-curve of 0.92 with a discriminator value of 11.2 mg/L. Using this cut-off value for UAC, sensitivity in predicting microalbuminuria is 85.0%, and specificity 85.0%. For ACR these values are, respectively: area-under-the-curve 0.93, discriminator value 9.9 mg/g, sensitivity 87.6%, and specificity 87.5%. Sensitivity for UAC in predicting microalbuminuria does not differ significantly from the sensitivity for ACR, whereas the difference between the specificities of UAC and ACR reaches statistical significance, but is numerically very small. In various subgroups characterized by differences in urinary creatinine excretion, the area-under-the-ROC curve, sensitivity, as well as specificity, do not increase relevantly compared to the results in the overall study population. This holds true for ACR as well as UAC. CONCLUSION: The diagnostic performance of measuring UAC in a spot morning urine sample in predicting microalbuminuria in subsequent 24-hour urine collections is satisfactory, and, moreover, comparable to that of measuring ACR. In order to keep the burden and costs involved in population screening for microalbuminuria as low as possible, we therefore propose prescreening by measuring UAC in a spot morning urine sample. Those subjects with a UAC above a certain predefined level (e.g., 11 mg/L) should be asked to collect timed urine samples.

Adult↗

Validation of insulin resistance indexes in a stable renal transplant population.

OBJECTIVE: The purpose of this study was to investigate the validity of established insulin resistance indexes, based on fasting blood parameters, in a stable renal transplant population. RESEARCH DESIGN AND METHODS: Fasting insulin, homeostasis model assessment (HOMA), the quantitative insulin sensitivity check index (QUICKI), and McAuley's index were assessed for correlation and agreement with whole-body glucose uptake (M value) divided by prevailing serum insulin concentrations (I value) assessed during a hyperinsulinemic-euglycemic clamp in 51 stable renal transplant recipients, who were at a median of 7.5 years after transplant. Multivariate linear regression analyses were used to determine independent risk factors for insulin resistance. RESULTS: The M/I value correlated with fasting insulin concentration (r = -0.56), HOMA (r = -0.53), QUICKI (r = 0.52), and McAuley's index (r = 0.61) (all P < 0.01). Linear regression showed agreement between all indexes and insulin resistance. However, McAuley's index showed the strongest agreement irrespective of age, sex, renal allograft function, and obesity. In multivariate analysis, fasting insulin concentration (beta = -0.59, P = 0.002), fasting triglyceride concentration (beta = -0.33, P = 0.04), and BMI (beta = -1.22, P = 0.05) were independently associated with the M/I value. CONCLUSIONS: All investigated insulin resistance indexes were valid estimates of insulin resistance in the long-term stable renal transplant population. However, correlation and agreement were strongest for McAuley's index. In addition to fasting insulin and triglyceride concentrations, of which McAuley's index is composed, only BMI seemed to be independently associated with insulin resistance in this population.

Adult↗

Trends in the incidence of treated end-stage renal failure in The Netherlands: hope for the future?

This study shows that in The Netherlands there is a changing pattern in incidence of renal replacement therapy over time when adjusted for age and sex. There has been an almost linear increase in crude incidence rates during four decades. However, unlike the situation elsewhere in the Western world, a flattening of the curve has been observed during the last six years. The growing incidence of end-stage renal disease (ESRD) due to especially hypertensive renovascular disease and diabetes mellitus type 2 has been neutralized by a decrease in ESRD due to glomerulonephritis, urologic interstitial nephritis, and diabetes mellitus type 1. The latter observations suggest that renoprotective interventions can be successful on a population level, and thus, provide hope for the future. To battle the increase in ESRD due to atherosclerosis and diabetes mellitus type 2-related renal disease, it is important that screening programs are being developed that enable us to identify in an early phase patients at risk for development of ESRD who may benefit from preventive strategies. Population screening for albuminuria will be helpful in this respect.

Humans↗

An elevated urinary albumin excretion predicts de novo development of renal function impairment in the general population.

BACKGROUND: We questioned which factors determine the risk for developing renal function impairment. To that purpose, we studied the incidence of newly diagnosed impaired renal function (GFR <60 mL/min/1.73m2) in the PREVEND cohort (N=8592), which is enriched for the presence of albuminuria, and which was first studied in 1997-1998. Of this cohort, 6894 subjects were studied again four years later. METHODS: Subjects with known renal disease, GFR <60 mL/min, missing GFR values, or sediment abnormalities at the first screening were excluded from the present analysis (N=872). We examined whether albuminuria is associated with the de novo development of an impaired renal function. GFR was 90.3 (SD 16.3) mL/min/1.73m2 at baseline, and 11.6% of the subjects had an albuminuria of more than 30 mg/day. RESULTS: After a follow-up of four years, 253 subjects (4.2%) were found to have a GFR <60 mL/min/1.73m2. The subjects with newly diagnosed impaired GFR were older, had a higher blood pressure, serum cholesterol, plasma glucose, and urinary albumin excretion at the first examination, and had a lower GFR to start with than those with a GFR >60 at the second evaluation. Subjects with de novo impaired GFR had a comparable BMI and smoked less frequently compared with subjects with GFR >60. In multivariate analysis, urinary albumin excretion was independently predictive for the risk of developing an impaired GFR (P=0.001). CONCLUSION: Also in the general population, measurement of urinary albumin excretion may prove to be a valuable tool to detect subjects at risk for later development of renal failure, independent of the presence of other cardiovascular risk factors.

Albuminuria↗

Which method for quantifying urinary albumin excretion gives what outcome? A comparison of immunonephelometry with HPLC.

BACKGROUND: Microalbuminuria has recently been identified as an independent risk factor for cardiovascular disease in the general population. Immunochemical urinary albumin assays only detect immunoreactive intact albumin. High performance liquid chromatography (HPLC) is able to detect both immunoreactive and immunounreactive intact albumin. We compared both measurement methods respectively in subjects with normo-, micro-, and macroalbuminuria in the general population. METHODS: We used 24-hour urine samples that were collected within the framework of the second screening for the PREVEND Study, a prospective cohort study on albuminuria in the city of Groningen, The Netherlands. RESULTS: With nephelometry as immunochemical reference method, we classified 986 subjects as normoalbuminuric, 283 as microalbuminuric, and 43 subjects as macroalbuminuric. The mean +/- SD albumin concentration was 6.8 +/- 4.3 mg/L for nephelometry in the urine samples of the 998 subjects with a concentration <20 mg/L according to nephelometry versus 17.6 +/- 10.3 mg/L for HPLC (P < 0.001, HPLC 159% higher). These values were 58.9 +/- 40.6 mg/L for nephelometry versus 74.0 +/- 51.8 mg/L for HPLC (P < 0.001, N = 280, HPLC 26% higher) in the concentration range between 20 to 200 mg/L, and 436.3 +/- 371.8 mg/L for nephelometry versus 399.1 +/- 329.2 mg/L for HPLC above 200 mg/L (P = 0.048, N = 34, HPLC 8.5% lower). Associations of 24-hour urinary albumin excretion with cardiovascular risk factors were generally somewhat stronger for nephelometry than for HPLC. Logistic regression analyses with an abnormal ankle-brachial index as outcome parameter revealed adjusted odds ratios of 1.78 (95%CI 1.01-3.12, P < 0.05) and 4.67 (95%CI 1.68-12.9, P < 0.05) respectively for micro- and macroalbuminuria as determined by HPLC, compared to 1.37 (95%CI 0.77-2.41, P = NS) and 3.85 (95%CI 1.53-9.67, P < 0.05) respectively for nephelometry. The ROC-curve showed similar sensitivity and specificity for both methods (P = 0.25). CONCLUSION: The use of HPLC for determination of urinary albumin concentrations reveals higher values compared to nephelometry, especially in the lower concentration range, resulting in a higher prevalence of microalbuminuria. With HPLC compared to nephelometry, we found a 21% higher independent odds ratio for microalbuminuria with the presence of peripheral vascular disease, and a 30% higher independent odds ratio for macroalbuminuria. This higher prevalence of microalbuminuria, accompanied with a similar absolute risk for peripheral vascular disease compared to patients with microalbuminuria detected by nephelometry, suggests HPLC to identify more people at risk, which is of great importance, especially when screening in large populations is concerned.

Albumins↗

Drawbacks of the use of indirect estimates of renal function to evaluate the effect of risk factors on renal function.

Many epidemiologic studies presently aim to evaluate the effect of risk factors on renal function. As direct measurement of renal function is cumbersome to perform, epidemiologic studies generally use an indirect estimate of renal function. The consequences of using different methods of renal function measurement in studies that evaluate the effect of cardiovascular risk factors on renal function were questioned. Data of the 8592 Prevention of Renal and Vascular End-stage Disease study participants, in whom the association was plotted between various cardiovascular risk factors and renal function measured either by creatinine clearance based on two 24-h urine collections or by the Cockcroft-Gault or Modification of Diet in Renal Disease formula were used. A repeated measurement analysis was used to compare the slopes of the linear regression lines of the risk factors and the different methods of renal function measurements. The relation between cardiovascular risk factors and renal function seems to be different when different methods for renal function are used. This was most pronounced for age, weight, and body mass index and less pronounced (but still statistical significant) for BP, cholesterol, and glucose. The relation between weight or body mass index and renal function showed completely different directions, depending on the renal function method used. In conclusion, the interpretation of the relation of cardiovascular risk factors and renal function is affected by the method selected to estimate renal function. For studying the relation of risk factors and renal function in large population studies, indirect estimates of renal function should be used with caution.

Body Mass Index↗