Modification Of Diet And Renal Disease Research Articles

Antiretroviral therapy as a risk factor for chronic kidney disease: Results from traditional regression modeling and causal approach in a large observational study.

ObjectiveWe investigated whether patients receiving selected antiretroviral combinations had a higher risk of chronic kidney disease (CKD) using traditional regression modeling and a causal approach in a large prospective cohort.Patients and methodsFor the purpose of this study, we selected 6301 patients who (i) started their first antiretroviral regimen after 1st January 2004, (ii) had at least one serum creatinine measurement within 6 months before ART initiation (study entry), and (iii) had at least two measurements after study entry. Baseline eGFR was defined from the last serum creatinine measurement before study entry. All eGFR values were calculated using the Modification of Diet and Renal Disease (MDRD) equation. Both traditional Cox proportional hazards model and Cox marginal structural models were applied. Distinct coding for antiretroviral therapy exposure were investigated as well as double robust estimators.ResultsOverall we showed that patients receiving tenofovir (TDF) with a ritonavir boosted protease inhibitor (rbPI) exhibited a higher risk of CKD compared with patients who received TDF with a non-nucleosidic reverse transcriptase inhibitor (NNRTI). Such an increased risk was observed considering both initial and current regimens. Our analysis revealed a clinician-driven switch away from TDF among persons experiencing a decline in renal function while receiving this drug.ConclusionOur results show that combination of TDF and boosted protease inhibitor is associated with a higher CKD risk than TDF and a NNRTI.

The Association of Daily Activity Levels and Estimated Kidney Function in Men and Women With Predialysis Chronic Kidney Disease

IntroductionChronic kidney disease (CKD) is often accompanied by complications including poor physical activity level. However, only a few studies have objectively characterized physical activity levels in predialysis CKD. Our study sought to measure daily activity levels by accelerometry in individuals with CKD (stages III−V) and to determine the association between daily activity and kidney function.MethodsWe determined kidney function by means of the estimated glomerular filtration rate (eGFR) using the Modification of Diet and Renal Disease (MDRD) equation. Participants wore an accelerometer for 7 consecutive days, and we measured multiple physical activity outcomes including total daily activity, sedentary, light, and moderate−vigorous activity. Average durations and intensity of activity were determined according to stage of CKD. The association between kidney function and activity level was determined by regression analysis.ResultsWe analyzed data from 110 individuals (60% men and 40% women) with stages III to V CKD. The mean age of our participants was 64 years, mean body mass index was 27.5 kg/m2, and mean eGFR was 23.7 ± 1.2 ml/min/1.73 m2. Our participants were primarily sedentary (mean duration of inactivity = 1152 ± 100 minutes per day; 79% of day). Light activity was performed 280 ± 99 minutes per day, and individuals participated in only 6 ± 9 minutes per day of moderate−vigorous activity. The eGFR did not predict physical activity level (P > 0.05 for all).DiscussionIndividuals with stages III to V CKD are sedentary, and do not meet the national recommendations of 150 minutes of moderate−vigorous activity per week. Further study is required to determine whether interventions to increase activity levels in patients with CKD are associated with improved health outcomes.

Plasma B-type natriuretic peptide concentration for diagnosis of acute heart failure with renal insufficiency

Background : Plasma B-type natriuretic peptide (BNP) is the diagnostic tool for acute heart failure (AHF).This natriu­retic peptide level depends on renal function, through renal metabolism and excretion. Therefore we examined the effect ofrenal impairment on plasma BNP level during diagnosis of AHF.Objective: The objective of the study was to assess the effect of renal dysfunction on plasma BNP level and to determine appropriate cutoff value of plasma BNP to diagnose the patients of AHF with renal insufficiency.Methods: This cross sectional analytical study was conducted in the Depart­ment of Biochemistry Bangabandhu Sheikh Mujib Medical University (BSMMU). The study was done among 90 AHF patients selected from cardiology emergency department during the period of July 2012 to June 2013. After enrollment plasma BNP concentration was measured and eGFR was estimated from serum creatinine by the four parameter Modifica­tion of Diet and Renal Disease (MORD) equation and then grouped into two groups on the basis of empirical cut off value of eGFR 60 ml/min/1.73 m2Results: In this study a significant negative correlation was found between plasma BNP evel and eGFR (P<0.001 ), with higher BNP levels observed as eGFR declined. The optimal BNP cutoff value for diagno­sis of AHF patients with renal insufficiency was 824 pg/ml. At this cutoff level AHF with renal insufficiency could be diagnosed with sensitivity and specificity of 84% and 71 %, respectively.Conclusions: By adjusting the cutoff value, plasma BNP can be used to diagnose AHF with renal insufficiency with an acceptable sensitivity and specificity.

Evaluation of estimated glomerular filtration rate and clinical variables in systemic sclerosis patients

The most important renal complication of systemic sclerosis (SSc) is scleroderma renal crisis (SRC). Many patients demonstrate less severe renal complications, most likely associated with reduced renal blood flow and a consequent reduction in glomerular filtration rate (GFR). The mechanism of this slowly progressive form of chronic renal disease is unclear. The aim of this study was to evaluate GFR by the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) and the 7-variable Modification of Diet and Renal Disease (MDRD) equations in SSc patients and to correlate estimated GFR (eGFR) with clinical variables of the disease. 105 unselected and consecutive patients with SSc were enrolled. Serum creatinine was measured in all patients and GFR was estimated by 7-variable MDRD and CKD-EPI equations. Nailfold videocapillaroscopy was performed in all patients. The mean value of eGFR evaluated by both 7-variable MDRD and CKD-EPI was significantly different (p < 0.0001) in the three capillaroscopic groups and correlated negatively with the severity of capillaroscopic damage (early: 95 ± 16 mL/min and 101 ± 12 mL/min, active: 86 ± 25 mL/min and 95 ± 17 mL/min, late: 76 ± 21 mL/min and 82 ± 21 mL/min). The mean value of eGFR evaluated by 7-variable MDRD (97 ± 23 mL/min vs. 74 ± 15 mL/min, p < 0.0001) and CKD-EPI< (0.83 ± 0.20 mL/min vs. 0.68 ± 0.10 mL/min, p < 0.0001) was significantly higher in SSc patients without history of digital ulcers than in those with. We can conclude that in SSc patients without renal involvement, eGFR decreases with the progression of digital vascular damage.

Estimating Glomerular Filtration Rate Using the Chronic Kidney Disease-Epidemiology Collaboration Creatinine Equation

Serum creatinine is measured more than 280 million times annually in the United States, and more than 80% of clinical laboratories now report an estimated glomerular filtration rate (GFR) when serum creatinine is measured.1,2 The most commonly used equation is the Modification of Diet and Renal Disease (MDRD) Study equation. Recently, the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) developed and validated a new equation, the CKD-EPI creatinine equation, which uses the same variables as the MDRD Study but is more accurate compared with measured GFR2,3; however, as for other diagnostic tests, other criteria are also important in clinical practice and public health, including detecting disease and predicting prognosis. Article see p 309 In this issue of Circulation: Heart Failure , McAlister and colleagues compare the CKD-EPI and MDRD Study equations for estimating prevalence of chronic kidney disease (CKD) and predicting mortality in a pooled individual patient dataset from 25 studies of 20 754 patients with heart failure included in the Meta-Analysis Global Group in Chronic Heart Failure (MAGGIC).4 CKD was defined as estimated glomerular filtration rate (eGFR) <60 mL/min per 1.73 m2 Mortality was defined as incidence per 1000 person years. During the average follow-up interval of 2.0 years, 4981 patients died. The authors showed that the CKD-EPI equation reclassified more people to lower than higher eGFR categories and more accurately predicted mortality risk than the MDRD Study equation. The finding of more accurate risk prediction using the CKD-EPI equation is consistent with previously published studies comparing the 2 equations for prediction of adverse outcomes (Table)4–9; however, in most other studies, reclassification to higher eGFR categories was more common than reclassification to lower eGFR categories. Understanding these findings requires some discussion of the GFR estimating equations …

Unexplained Anemia In the Elderly (UAE) Predominates as the Major Anemia Category In Racially Diverse Cohort of Older Persons Despite An Intensive Evaluation

AbstractAbstract 3215 Introduction:Anemia is a common condition among older adults associated with substantial morbidity and mortality. Previous studies indicate that no discernible etiology (i.e., UAE) occurs in around 1/3rd of elderly anemia pts. Limited data exist regarding prospective and careful evaluation to establish the full spectrum and incidence of the diverse etiologies of anemia in the elderly. In addition, minimal data are available for non-white populations. Methods:We prospectively studied 174 subjects 65 yrs and older referred to the University of Chicago Hematology Clinic primarily for evaluation of anemia defined by hemoglobin (Hb) < 13.0 g/dL and < 12.0 g/dL for men and women, respectively. An extensive standardized history, physical and laboratory evaluation ensued with bone marrow (BM) evaluation as indicated. A diagnostic algorithm was applied for anemia categorization with specific criteria, which included a designation of iron deficiency anemia (IDA) for a serum ferritin < 50 ng/mL or lack of erythroid response after iron repletion. Chronic kidney disease (CKD) related anemia required an estimated GFR of < 30 mL/min/1.73m2 applying the four-variable Modification of Diet and Renal Disease (MDRD) study group criteria. Results:Median age was 76 yrs and 60.3% of pts were female. African-Americans (AA) accounted for 69% of pts and whites were 27%. Hypertension and diabetes were frequent at 79% and 39%, respectively. The median hemoglobin (Hb) was 10.2 g/dL and mean MCV of 88. Approximately 17% of pts had received red blood cell (RBC) transfusion in the prior 3 months. Median eGFR was 61.5. C-reactive protein was ' 3 mg/dL in 52%. BM examination was performed in 24.8%. Prevalence of anemia etiologies versus UAE are summarized in Table 1. UAE predominated at 43.7%, followed by IDA at 25%. BM established a hematologic malignancy in 13 (7.5%), including six cases of MDS (4%) and two cases of AML (0.5%). Hematologic parameters in UAE showed the following mean values: Hb of 10.8 g/dL; MCV of 89.9 fL; RDW of 14.6 (normal <15%); and suppressed absolute reticulocyte count at 45.0 K/uL. Only 4/76 (5.3%) of UAE received RBCs within the prior 3 months. Two of these had previously had bleeding and at evaluation had a stable low Hb without an etiology. Thus, in the entire cohort, only 2/29 (6.9%) received RBCs without an explanation. The proportion of AA and whites diagnosed with either UAE or IDA did not differ (p=0.835). Specifically, 23/46 (50%) whites had UAE compared to 48/117 (41.0%) of AA where as 12/26 (26.1%) of whites had IDA and 28/117 (23.9%) of AA had IDA. Figure 1 depicts EPO levels for UAE, IDA, and MDS/AML. Serum EPO levels showed no significant correlation with Hb for UAE (r = - 0.15, p=0.019) but showed a significant inverse correlation with Hb among IDA pts (r = -0.63, p<0.0001). The suppressed EPO in UAE compared to IDA was not explained by renal dysfunction as mean eGFR was 64.2 for UAE versus 60.0 in IDA (p=0.30). [Display omitted] Conclusions:The data confirm UAE is a hypoproliferative normocytic anemia with suppressed EPO levels that rarely requires RBC transfusions. An intensive hematologic evaluation reveals a wide number of etiologies for anemia among older adults, including 7.5% with hematologic malignancies. Nevertheless, UAE predominates as the most common anemia category in the elderly in both whites and AA's.Anemia Etiology Among Older Adults Disclosures:No relevant conflicts of interest to declare.

The inaccuracy of cystatin C and creatinine-based equations in predicting GFR in orthotopic liver transplant recipients

As survival with an orthotopic liver transplant (OLT) improves, the incidence of chronic kidney disease in OLT recipients increases. Measurement of kidney function using creatinine-based estimates is often inaccurate, while cystatin C may overcome the biases that effect creatinine. The aim of this study was to assess the accuracy of creatinine- and cystatin C-based equations to estimate kidney function in long-term OLT recipients. This was a cross-sectional study performed on OLT recipients within a single liver transplant centre where creatinine (n = 41) and cystatin C (n = 30) were measured and glomerular filtration rate (GFR) estimated using the Modification of Diet and Renal Disease (MDRD), Cockcroft-Gault (CG), Hoek, Larsson, Filler and Le Bricon equations. Comparison was made with the nuclear GFR (nGFR) (n = 41) measured through 51-Cr EDTA clearance. The mean age of recipients was 56 +/- 13 years, and they were 6.5 +/- 4.7 years post-OLT. Fifty-six percent of recipients had a nGFR < or =60 mL/min/1.73 m(2). nGFR correlated significantly with all predictive equations (P < 0.001). The MDRD, CG and Le Bricon equations had the smallest degree of bias (-7.6, -7.3 and 3.4 mL/min/1.73 m(2), respectively), with 22%, 22% and 27% of estimates, respectively, being within 10% of nGFR measurements. In OLT recipients with nGFR < or =60 mL/min/1.73 m(2), the degree of bias of both the creatinine-base MDRD and cystatin-based Hoek equations was within 2 mL/min/1.73 m(2) difference between the measured and estimated GFR, but 41% and 36% of estimates were within 10% of the nGFR measurement. Therefore, the degree of inaccuracy in cystatin C- and creatinine-based predictive equations brings into question their clinical utility in OLT recipients. We have no evidence that cystatin C is superior to creatinine in this population.

Comparing carboplatin dose administered to the calculated dose using the Modification of Diet and Renal Disease (MDRD) equation

13003 Background: Renal function assessment is vital for dosing of chemotherapy drugs. GFR is usually estimated by creatinine clearance (CrCl). The MDRD equation is thought to provide a more accurate estimation of GFR than the Cockcroft-Gault or 24-hour CrCl measurement. Although this formula has been validated in kidney disease, it has not been extensively studied in cancer patients. Methods: We retrospectively reviewed records for patients who received carboplatin from the University of Illinois at Chicago for a 4-year study period. General demographic information, carboplatin dose for cycles one to three, and common laboratory parameters at baseline and following cycles one to three were collected. The MDRD derived value of GFR was then used in the Calvert equation to calculate carboplatin dose. This calculated dose was compared to the actual dose administered in the first cycle. From this comparison, the records were divided into two groups: (A) actual vs. calculated dose ≥ 20% and (B) actual vs. calculated dose &lt; 20%. We then assessed toxicity by determining the frequency in each group requiring dose reduction on the second cycle of carboplatin. Results: Data are available for 116 patient comparisons. 78 patient comparisons were in group B with agreement between actual vs. calculated MDRD dose. 38 were in group A with 36 having the actual dose being ≥ 20% less than the MDRD-calculated dose. Wilcoxin and Chi analysis reveals statistical significance for African American, women, lower serum creatinine, and older age for Group A. In Group A, cycle 2 dose reductions were made in 3 cases (8% and due to hematologic). In Group B, cycle 2 dose reductions were made in 12 cases. In 8 of these cases (10%), dose reductions were based on ANC, and in 4 cases dose reductions were made likely on the basis of changes in weight or creatinine. Conclusion: In the comparisons examined to date, differences in carboplatin doses due to different methods of calculation do not appear to significantly influence the frequency of dose reduction. Factors used in calculating MDRD such as age, sex, serum creatinine, and ethnicity were variables associated with ≥ 20% difference in actual vs. calculated MDRD dose. No significant financial relationships to disclose.

Impact of implementation of the MELD scoring system on the prevalence and incidence of chronic renal disease following liver transplantation

The implementation of the model for end-stage liver disease (MELD) score decreased mortality of those awaiting liver transplantation (LT); however, the impact of the MELD allocation system on the risk of chronic renal disease after LT remains unknown. We conducted a non-concurrent single-center cohort study of 174 patients undergoing LT at our center. We compared patients who underwent LT one year prior to MELD implementation (pre-MELD cohort) to those patients who underwent LT 1 year following MELD implementation (MELD cohort). All patients were followed for at least 2 years after LT. Stage 3 chronic renal disease (CRD-3) was defined by an estimated creatinine clearance (CL(Cr)) below 60 ml/min/1.73 m2, and stage 4 chronic renal disease (CRD-4) was defined by an estimated CL(Cr) below 30 mL/min/1.73 m2 according to the validated Modification of Diet and Renal Disease (MDRD) formula. Requirement of kidney transplantation and need for hemodialysis were also evaluated following LT. The pre-MELD cohort (n=97) and the MELD cohort (n=77) were comparable in baseline characteristics, prevalence of diabetes and hypertension, and immunosuppression. Mean calculated MELD score in the pre-MELD cohort was significantly lower than in the MELD cohort (16 vs. 19, P < 0.05). The estimated CL(Cr) at time of LT was lower in the MELD cohort compared with the pre-MELD cohort (75 vs. 95, P < 0.01). However, the incidence and prevalence of CRD-3 and CRD-4 at 6, 12, and 24 months after LT were comparable between the two cohorts. Need for kidney transplantation or hemodialysis after LT was comparable between the groups. In multivariate analysis, serum creatinine at LT was the only variable associated with the development of CRD-3 in the first 2 years after LT. In conclusion, the implementation of the MELD allocation system is not associated with increased mortality or occurrence of CRD-3 or CRD-4 in the first 2 years after LT.