Background Guidelines recommend estimation of glomerular filtration rate (eGFR) prior to iodine contrast media (CM) examinations. It is also recommended that absolute eGFR in mL/min, not commonly used relative GFR (adjusted to body surface area; mL/min/1.73?m(2)), should be preferred when dosing and evaluating toxicity of renally excreted drugs. Purpose To validate the absolute Lund-Malmö equation (LM-ABS) in comparison with the absolute Cockcroft-Gault (CG) equation and the relative equations, revised Lund-Malmö (LM-REV), MDRD, and CKD-EPI, after converting relative estimates to absolute values, and to analyze change in eGFR classification when absolute instead of relative eGFR was used. Material and Methods A total of 3495 plasma clearance of iohexol to measure GFR (mGFR) served as reference test. Bias, precision, and accuracy (percentage of estimates ±30% of mGFR; P30) were compared overall and after stratification for various mGFR, eGFR, age, and BMI subgroups. Results The overall P30 results of CG/LM-ABS/LM-REV/MDRD/CKD-EPI were 62.8%/84.9%/83.7%/75.3%/75.6%, respectively. LM-ABS was the most stable equations across subgroups and the only equation that did not exhibit marked overestimation in underweight patients. For patients with relative eGFR 30-44 and 45-59?mL/min/1.73?m(2), 36% and 58% of men, respectively, and 24% and 32% of women, respectively, will have absolute eGFR values outside these relative eGFR intervals. Conclusion Choosing one equation to estimate GFR prior to contrast medium examinations, LM-ABS may be preferable. Unless absolute instead of relative eGFR are used, systematic inaccuracies in assessment of renal function may occur in daily routine and research on CM nephrotoxicity may be flawed.
The aim of the present study was to evaluate acute kidney injury (AKI) with cystatin C following transcatheter aortic valve implantation (TAVI) and to assess the impact of postoperative AKI on outcome and late renal function.
A prospective study.
Single, tertiary referral center.
Sixty-eight consecutive patients with severe aortic stenosis and advanced comorbidity.
Blood samples were collected on 4 occasions pre- and postoperatively to determine levels of s-creatinine and cystatin C. Additionally, a sample was collected at followup 12 months postoperatively for the determination of s-creatinine.
The mean preoperative eGFR (s-creatinine) was 67±24 mL/min/1.73 m² compared to 45±21 mL/min/1.73 m² with eGFR (cystatin C) (p
The Cockcroft Gault formula is often used to calculate the glomerular filtration rate (GFR) from plasma creatinine results. In Sweden this calculation is not usually done in the laboratory, but locally in the wards. These manual calculations could cause erroneous results. In several studies plasma cystatin C has been shown to be superior to plasma creatinine for estimation of GFR. One limitation of using cystatin C as a GFR marker is that there is no conversion formula transforming cystatin C expressed as mg/L to GFR expressed as mL/min. In this study plasma creatinine and cystatin C were compared with iohexol clearance. A stronger correlation (p
Guidelines for recommended medication use for the secondary prevention of coronary heart disease are exceedingly important in patients with chronic kidney disease. Despite a high risk for recurrent cardiovascular events, these patients are less likely to use evidence-based recommended medications. The objective of the current study was to analyze the association between renal function and guideline-recommended drug therapy in patients with coronary heart disease.
In this nationwide population-based cohort study, we included 12,332 patients with established coronary heart disease who underwent primary isolated coronary artery bypass grafting in Sweden between 2005 and 2008. Medication use was retrieved from the national Prescribed Drug Register.
During the first year after coronary surgery, 94% of patients had at least two dispensed prescriptions for an antiplatelet agent, 68% for an angiotensin-converting enzyme inhibitor or angiotensin II receptor blocker, 92% for a beta-blocker, and 93% for a statin. Only 57% of all patients had prescriptions for all four medication classes. Reduced renal function (estimated glomerular filtration rate (eGFR) of 30 to 45 mL/min per 1.73 m(2) and 60 mL/min per 1.73 m(2)).
In patients with established coronary heart disease, moderate to severe renal dysfunction was associated with significantly lower use of guideline-recommend medications as compared to normal renal function.
The effects of kidney disease on the risk of hospitalization or death from specific noncardiovascular causes, including pneumonia, are unclear. The objective of this study is to determine the associations between estimated glomerular filtration rate (eGFR) and hospitalization or death with pneumonia.
Retrospective cohort study.
Community-based study from a Canadian health region of 252,516 participants with 1 or more outpatient serum creatinine measurements from July 1, 2003, to June 30, 2004, who were not receiving dialysis or kidney transplantation.
eGFR calculated by using the 4-variable Modification of Diet in Renal Disease Study equation.
Hospitalization with pneumonia or death within 30 days after pneumonia hospitalization.
Cox proportional hazards models adjusted for age, sex, socioeconomic status, and comorbidities with censoring at death, initiation of renal replacement therapy, or emigration.
Lower eGFR was associated with increased risk of hospitalization with pneumonia, although the magnitude of effect varied with age. The risk associated with decreased eGFR was greatest in participants 18 to 54 years old; compared with participants with an eGFR of 60 to 104 mL/min/1.73 m(2), adjusted hazard ratios for hospitalization with pneumonia were 3.23 (95% confidence interval, 2.40 to 4.36) in those with eGFR of 45 to 59 mL/min/1.73 m(2), 9.67 (95% confidence interval, 6.36 to 14.69) for eGFR of 30 to 44 mL/min/1.73 m(2), and 15.04 (95% confidence interval, 9.64 to 23.47) for eGFR less than 30 mL/min/1.73 m(2). Associations became weaker with increasing age, although the graded inverse association between lower eGFR and risk remained for older participants. An age-dependent inverse relationship also was observed between eGFR and risk of death within 30 days of hospitalization with pneumonia.
Residual confounding caused by severity of illness or unmeasured comorbidities may be present.
The risk of hospitalization and death with pneumonia is greater at lower eGFRs, especially in younger adults. This association may contribute to excess mortality in people with chronic kidney disease.
Comment In: Am J Kidney Dis. 2009 Jul;54(1):1-319559334
To compare the recently developed CKD-EPI equation to estimate GFR in adult Swedish-Caucasians with the MDRD equation.
Swedish-Caucasians (N = 850, 376 females; median age 60, range 5-95 years) referred for plasma iohexol-clearance (median 55, range 5-223 mL/min/1.73 m²) constituted the Lund-Malmö Study cohort. Bias, precision (interquartile range, IQR, of the differences between estimated and measured GFR), accuracy expressed as percentage of estimates ±10% (P10) and ±30% (P30) of measured GFR, and classification ability for five GFR stages
The recent decline in the number of new patients undergoing dialysis and transplantation in the United States may be linked to a reduction in the incidence of early-start dialysis, defined as the initiation of renal replacement therapy (RRT) at an estimated GFR =10 ml/min per 1.73 m(2). We examined the most recent data from the U.S. Renal Data System to determine how this trend will affect the future incidence of ESRD in the United States. The percentage of early dialysis starts grew from 19% to 54% of all new starts between 1996 and 2009 but remained stable between 2009 and 2011. Similarly, the incident RRT population increased substantially in all age groups between 1996 and 2005, with the largest increase occurring in patients aged =75 years. Early dialysis starts accounted for most of the increase in the incident RRT population in all age groups during this time period, and between 2005 and 2010, the increase slowed dramatically. Although the future incident RRT population will be determined in part by population growth, these results suggest that later dialysis starts and greater use of conservative and palliative care, which may improve quality of life for elderly patients with advanced renal failure, will continue to attenuate the increase observed in previous years.
Whilst chronic kidney disease (CKD) has been identified as a risk factor for the development of acute kidney injury (AKI), little has been published about the incidence and outcomes of those acute injuries on chronic stable kidney disease and even less in a referred cohort of CKD patients followed up by nephrologists.
We followed up 6862 patients registered as CKD in British Columbia, Canada for a median time of 19.4 months after they achieved an estimated glomerular filtration rate (eGFR) value or =25% compared to a moving baseline eGFR within 25 days.
Of the CKD patients, 44.9% had at least one AKI episode. Crude incidence rate for a first AKI event was 34.8 per 100 person-years. Older age [adjusted relative risks (RR) = 0.93 by 10 years, 95% confidence intervals (CI) = 0.90, 0.95] was associated with a lower risk of AKI. Of the patients, 15.3% died before dialysis and 18.1% initiated dialysis. AKI was associated with both a higher risk of death (adjusted RR = 2.32, 95% CI = 2.04, 2.64) and an increased risk of dialysis (adjusted RR = 2.33, 95% CI = 2.07, 2.61).
In a referred CKD population, AKI was a frequent event and associated with higher risks of dialysis and mortality. The incidence of AKI appears to be less with older age in this population. Quantification of AKI incidence and its risk factors in different populations is important for clinicians and planners, so that appropriate identification, prevention and treatment strategies can be tested.
Nephrogenic systemic fibrosis (NSF) is a rare condition that may follow administration of gadolinium-based contrast media (Gd-CM) in patients with renal insufficiency. This study was initiated to determine the incidence of NSF at Skåne University Hospital, Malmö, in Sweden.
During the period January 2001 to December 2008 10 650 patients underwent magnetic resonance imaging (MRI) examinations. The re-expressed four-variable Modification of Diet in Renal Disease (MDRD) equation was used to calculate the estimated glomerular filtration rate (eGFR). The 272 patients with an eGFR
OBJECTIVE: Estimation of the glomerular filtration rate (GFR) is essential for the evaluation of patients with kidney disease, and for correct dosage of drugs that are eliminated from the circulation by the kidneys. In most cases GFR is estimated based on serum creatinine and the Modification of Diet in Renal Disease (MDRD) formula. As both cystatin C and creatinine are used for the determination of GFR it is important to investigate if estimated GFR by the two methods differ in various patient groups. DESIGN AND METHODS: We have compared cystatin C and MDRD estimated GFR calculated from the same request from primary care units (n=488), a cardiology ward (n=826), the cardiointensive care unit (n=1026), two oncology wards (n=919 and 1021), and the neurosurgical intensive care unit (n=1515) in an observational cross-sectional study. RESULTS: We found better agreement between the two GFR estimates in samples from primary care patients and patients in the cardiology wards, than in samples from oncology wards or the neurosurgical intensive care unit. In the latter settings there was a pronounced difference between the two GFR estimates. CONCLUSION: The comparisons show that differences in patient selections have a strong impact on the agreement between cystatin C and MDRD estimated glomerular filtration rate.