6 research outputs found
Extracellular fluid volume and glomerular filtration rate in 1,878 healthy potential renal transplant donors. Effects of age, gender, obesity and scaling.
Aim. The aim of this study was to investigate the influence of age, gender, obesity and scaling on glomerular filtration rate (GFR) and extracellular fluid volume (ECV) in healthy subjects.
Methods. This is a retrospective multi-centre study of 1878 healthy prospective kidney transplant donors (819 men) from 15 centres. Age and body mass index (BMI) were not significantly different between men and women. Slope-intercept GFR was measured (using Cr-51-EDTA in 14 centres; Tc-99m-DTPA in one) and scaled to body surface area (BSA) and lean body mass (LBM), both estimated from height and weight. GFR was also expressed as the slope rate constant, with one-compartment correction (GFR/ECV). ECV was measured as the ratio, GFR to GFR/ECV.
Results. ECV was age independent but GFR declined with age, at a significantly faster rate in women than men. GFR/BSA was higher in men but GFR/ECV and GFR/LBM were higher in women. Young women (65 years). There was no difference in GFR between obese (BMI > 30 kg/m2) and non-obese men. Obese women, however, had lower GFR than non-obese women and negative correlations were observed between GFR and both BMI and %fat. The decline in GFR with age was no faster in obese versus non-obese subjects. ECV/BSA was higher in men but ECV/LBM was higher in women. ECV/weight was almost gender independent, suggesting that fat-free mass in women contains more extracellular water. BSA is therefore a misleading scaling variable.
Conclusion. There are several significant differences in GFR and ECV between healthy men and women
The reliability of glomerular filtration rate measured from plasma clearance: a multi-centre study of 1,878 healthy potential renal transplant donors
PURPOSE
The objective of the study was to undertake a clinical audit of departmental performance in the measurement of glomerular filtration rate (GFR) using the coefficient of variation (CV) of extracellular fluid volume (ECFV) as the benchmark. ECFV is held within narrow limits in healthy subjects, narrower than GFR, and should therefore have a low CV.
METHODS
Fifteen departments participated in this retrospective study of healthy renal transplant donors. Data were analysed separately for men (n ranged from 28 to 115 per centre; total = 819) and women (n = 28-146; 1,059). All centres used the slope-intercept method with blood sample numbers ranging from two to five. Subjects did not fast prior to GFR measurement. GFR was scaled to body surface area (BSA) and corrected for the single compartment assumption. GFR scaled to ECFV was calculated as the terminal slope rate constant and corrected for the single compartment assumption. ECFV/BSA was calculated as the ratio of GFR/BSA to GFR/ECFV.
RESULTS
The departmental CVs of ECFV/BSA and GFR/BSA ranged from 8.3 to 25.8% and 12.8 to 21.9%, respectively, in men, and from 9.6 to 21.1% and 14.8 to 23.7%, respectively, in women. Both CVs correlated strongly between men and women from the same centre, suggesting department-specific systematic errors. GFR/BSA was higher in men in 14 of 15 centres, whereas GFR/ECFV was higher in women in 14 of 15 centres. Both correlated strongly between men and women, suggesting regional variation in GFR.
CONCLUSION
The CV of ECFV/BSA in normal subjects is a useful indicator of the technical robustness with which GFR is measured and, in this study, indicated a wide variation in departmental performance
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Aspirin Effects on Mortality and Morbidity in Patients With Diabetes Mellitus: Early Treatment Diabetic Retinopathy Study Report 14
Objectives.—This report presents information on the effects of aspirin on mortality, the occurrence of cardiovascular events, and the incidence of kidney disease in the patients enrolled in the Early Treatment Diabetic Retinopathy Study (ETDRS).Study Design.—This multicenter, randomized clinical trial of aspirin vs placebo was sponsored by the National Eye Institute.Patients.—Patients (N=3711) were enrolled in 22 clinical centers between April 1980 and July 1985. Men and women between the ages of 18 and 70 years with a clinical diagnosis of diabetes mellitus were eligible. Approximately 30% of all patients were considered to have type I diabetes mellitus, 31% type II, and in 39% type I or II could not be determined definitely.Intervention.—Patients were randomly assigned to aspirin or placebo (two 325-mg tablets once per day).Main Outcome Measures.—Mortality from all causes was specified as the primary outcome measure for assessing the systemic effects of aspirin. Other outcome variables included cause-specific mortality and cardiovascular events.Results.—The estimate of relative risk for total mortality for aspirin-treated patients compared with placebo-treated patients for the entire study period was 0.91 (99% confidence interval, 0.75 to 1.11). Larger differences were noted for the occurrence of fatal and nonfatal myocardial infarction; the estimate of relative risk was 0.83 for the entire follow-up period (99% confidence interval, 0.66 to 1.04).Conclusions.—The effects of aspirin on any of the cardiovascular events considered in the ETDRS were not substantially different from the effects observed in other studies that included mainly nondiabetic persons. Furthermore, there was no evidence of harmful effects of aspirin. Aspirin has been recommended previously for persons at risk for cardiovascular disease. The ETDRS results support application of this recommendation to those persons with diabetes at increased risk of cardiovascular disease.(JAMA. 1992;268:1292-1300