Application of the European Kidney Function Consortium Equation to Estimate Glomerular Filtration Rate: A Comparison Study of the CKiD and CKD-EPI Equations Using the Korea National Health and Nutrition Examination Survey (KNHANES 2008-2021)

Background and Objectives: The European Kidney Function Consortium (EKFC) equation has been newly proposed for estimating glomerular filtration rate (eGFR) across the spectrum of age. We compared the EKFC equation with the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equations in a large-scale Korean population. Materials and Methods: Using the representative Korean health examination data, the Korea National Health and Nutrition Examination Survey (KNHANES 2008-2021), the records of 91,928 subjects (including 9917 children) were analyzed. We compared the EKFC equation with CKiD, CKD-EPI 2009, and CKD-EPI 2021 equations and investigated their agreement across GFR categories. Results: In the total population, the CKD-EPI 2021 equation yielded the highest eGFR value, followed by the CKD-EPI 2009 and EKFC equations. In children, the distribution of eGFR differed significantly between the EKFC and CKiD equations (p < 0.001), with a wider range of eGFR values found with the CKiD equation. Each equation showed weak or moderate agreement on the frequency of the GFR category (κ = 0.54 between EKFC and CKD-EPI 2021; κ = 0.77 between EKFC and CKD-EPI 2009). The eGFR values found by the EKFC equation showed high or very high correlations with those by the CKiD, CKD-EPI 2009, and CKD-EPI 2021 equations (r = 0.85, 0.97, and 0.97, respectively). As eGFR values increased, bigger differences were observed between equations. Conclusions: This large-scale study demonstrates that the EKFC equation would be applicable across the entire age spectrum in Asian populations. It also underscores that national kidney health would be highly affected by an eGFR equation being implemented. Additional investigation and more caution would be warranted for the transition of eGFR equations.

Updated US Prevalence Estimates for Chronic Kidney Disease Stage and Complications Using the New Race-Free Equation to Estimate Glomerular Filtration Rate

This cross-sectional study investigates US population changes in chronic kidney disease (CKD) G stage and 4 CKD-related complications, comparing the 2021 equation for estimating glomerular filtration rate with the 2009 equation, which included a race coefficient.

Comparing Cystatin C- and Creatinine-Estimated Glomerular Filtration Rates in Patients With Thoracic Versus Sacral Motor Levels of Spina Bifida

OBJECTIVE

Patients with myelomeningocele-type spina bifida are at increased risk of developing kidney disease from neurogenic bladder. Differences between creatinine- and cystatin C-estimated glomerular filtration rates were examined in patients with thoracic versus sacral level myelomeningocele given presumed differences in muscle mass.

DESIGN

A retrospective chart review (2005-2018) was performed on 57 adults with myelomeningocele [thoracic n = 44 (77%); sacral n = 13 (23%)]. Concurrently obtained creatinine and cystatin C levels were extracted and calculated creatinine- and cystatin C-estimated glomerular filtration rates were compared.

RESULTS

Mean creatinine-estimated glomerular filtration rate was significantly higher for thoracic [140.8 ml/min (SD = 23.9)] versus sacral myelomeningocele [112.0 ml/min (SD = 22.6), P = 0.0003]. There was no difference in cystatin C-estimated glomerular filtration rate between sacral [116.6 ml/min (SD = 23.7)] and thoracic myelomeningocele [124.8 ml/min (SD = 17.9)]. The mean difference between creatinine- and cystatin C-estimated glomerular filtration rates in thoracic myelomeningocele [24.2 ml/min (SD = 16.3)] was significantly greater than in sacral myelomeningocele [-12.8 (SD = 15.7), P < 0.0001].

CONCLUSIONS

There was a significantly higher discrepancy between creatinine- and cystatin C-estimated glomerular filtration rates in thoracic versus sacral motor levels of myelomeningocele. These data suggest that creatinine-estimated glomerular filtration rate may overestimate kidney function in patients with thoracic myelomeningocele. Providers who manage patients with thoracic myelomeningocele should consider monitoring cystatin C to evaluate for underlying renal disease.

Prevalence of impaired renal function and determinants in the southwest of Iran

BACKGROUND

Chronic kidney disease (CKD) is a growing global health problem with faster progression in developing countries such as Iran. Here we aimed to evaluate the prevalence and determinants of CKD stage III+.

METHODS

This research is part of the Khuzestan Comprehensive Health Study (KCHS), a large observational population-based cross-sectional study in which 30,041 participants aged 20 to 65 were enrolled. CKD was determined with estimated glomerular filtration rate (eGFR) less than 60 ml/min/1.73m2, based on two equations of Modification of Diet in Renal Disease (MDRD) and Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI). The multivariate logistic regression was used to evaluate the CKD stage III+ determinants.

RESULTS

Prevalence of CKD stage III+ is estimated to be 7.1, 5.5, and 5.4% based on MDRD, CKD-EPI, and combination of both equations, respectively. More than 89% of CKD subjects aged higher than 40 years. In regression analysis, age more than 40 years had the strongest association with CKD stage III+ probability (OR: 8.23, 95% CI: 6.91-9.18). Higher wealth score, hypertension, High-Density Lipoprotein levels less than 40 mg/dl, and higher waist to hip ratio were all associated with CKD stage III+ while Arab ethnicity showed a protective effect (OR: 0.69, 95% CI: 0.57-0.78).

CONCLUSION

Our findings provide detailed information on the CKD stage III+ and its determinants in the southwest region of Iran. Due to strong association between age and CKD stage III+, within a few decades we might expect a huge rise in the CKD prevalence.

The impact of measuring split kidney function on post-donation kidney function: A retrospective cohort study

Background

Studies have reported agreement between computed tomography (CT) and renography for the determination of split kidney function. However, their correlation with post-donation kidney function remains unclear. We compared CT measurements with renography in assessment of split kidney function (SKF) and their correlations with post-donation kidney function.

Methods

A single-centre, retrospective cohort study of 248 donors from January 1, 2009-July 31, 2019 were assessed. Pearson correlations were used to assess post-donation kidney function with renography and CT-based measurements. Furthermore, we examined high risk groups with SKF difference greater than 10% on renography and donors with post-donation eGFR less than 60 mL/min/1.73m².

Results

62% of donors were women with a mean (standard deviation) pre-donation eGFR 99 (20) and post-donation eGFR 67 (22) mL/min/1.73m² at 31 months of follow-up. Post-donation kidney function was poorly correlated with both CT-based measurements and renography, including the subgroup of donors with post-donation eGFR less than 60 mL/min/1.73m² (r less than 0.4 for all). There was agreement between CT-based measurements and renography for SKF determination (Bland-Altman agreement [bias, 95% limits of agreement] for renography vs: CT volume, 0.76%, -7.60–9.15%; modified ellipsoid,1.01%, -8.38–10.42%; CC dimension, 0.44%, -7.06–7.94); however, CT missed SKF greater than 10% found by renography in 20 out 26 (77%) of donors.

Conclusions

In a single centre study of 248 living donors, we found no correlation between CT or renography and post-donation eGFR. Further research is needed to determine optimal ways to predict remaining kidney function after donation.

Derivation and validation of a machine learning risk score using biomarker and electronic patient data to predict progression of diabetic kidney disease

AIM

Predicting progression in diabetic kidney disease (DKD) is critical to improving outcomes. We sought to develop/validate a machine-learned, prognostic risk score (KidneyIntelX™) combining electronic health records (EHR) and biomarkers.

METHODS

This is an observational cohort study of patients with prevalent DKD/banked plasma from two EHR-linked biobanks. A random forest model was trained, and performance (AUC, positive and negative predictive values [PPV/NPV], and net reclassification index [NRI]) was compared with that of a clinical model and Kidney Disease: Improving Global Outcomes (KDIGO) categories for predicting a composite outcome of eGFR decline of ≥5 ml/min per year, ≥40% sustained decline, or kidney failure within 5 years.

RESULTS

In 1146 patients, the median age was 63 years, 51% were female, the baseline eGFR was 54 ml min-1 [1.73 m]-2, the urine albumin to creatinine ratio (uACR) was 6.9 mg/mmol, follow-up was 4.3 years and 21% had the composite endpoint. On cross-validation in derivation (n = 686), KidneyIntelX had an AUC of 0.77 (95% CI 0.74, 0.79). In validation (n = 460), the AUC was 0.77 (95% CI 0.76, 0.79). By comparison, the AUC for the clinical model was 0.62 (95% CI 0.61, 0.63) in derivation and 0.61 (95% CI 0.60, 0.63) in validation. Using derivation cut-offs, KidneyIntelX stratified 46%, 37% and 17% of the validation cohort into low-, intermediate- and high-risk groups for the composite kidney endpoint, respectively. The PPV for progressive decline in kidney function in the high-risk group was 61% for KidneyIntelX vs 40% for the highest risk strata by KDIGO categorisation (p < 0.001). Only 10% of those scored as low risk by KidneyIntelX experienced progression (i.e., NPV of 90%). The NRIevent for the high-risk group was 41% (p < 0.05).

CONCLUSIONS

KidneyIntelX improved prediction of kidney outcomes over KDIGO and clinical models in individuals with early stages of DKD.

Longitudinal Causal Effects of Normalized Protein Catabolic Rate on All-Cause Mortality in Patients With End-Stage Renal Disease: Adjusting for Time-Varying Confounders Using the G-Estimation Method

In this study, we aimed to estimate the causal effect of normalized protein catabolic rate (nPCR) on mortality among end-stage renal disease (ESRD) patients in the presence of time-varying confounding affected by prior exposure using g-estimation. Information about 553 ESRD patients was retrospectively collected over an 8-year period (2011-2019) from hemodialysis facilities in Kerman, Iran. nPCR was dichotomized as <1.2 g/kg/day versus ≥1.2 g/kg/day. Then a standard time-varying accelerated failure time (AFT) Weibull model was built, and results were compared with those generated by g-estimation. After appropriate adjustment for time-varying confounders, weighted g-estimation yielded 78% shorter survival time (95% confidence interval (95% CI): -81, -73) among patients with a continuous nPCR <1.2 g/kg/day than among those who had nPCR ≥1.2 g/kg/day during follow-up, though it was 18% (95% CI: -57, 54) in the Weibull model. Moreover, hazard ratio estimates of 4.56 (95% CI: 3.69, 5.37) and 1.20 (95% CI: 0.66, 2.17) were obtained via weighted g-estimation and the Weibull model, respectively. G-estimation indicated that inadequate dietary protein intake characterized by nPCR increases all-cause mortality among ESRD patients, but the Weibull model provided an effect estimate that was substantially biased toward the null.

Apixaban in Patients with Atrial Fibrillation and Severe Renal Dysfunction: Findings from a National Registry

BACKGROUND

Real-world information regarding the use of direct oral anticoagulants therapy and the outcome in patients with renal dysfunction is limited.

OBJECTIVES

To evaluate the clinical characteristics and outcomes of patients with atrial fibrillation (AF) and severe renal dysfunction who are treated with apixaban.

METHODS

A sub-analysis was conducted within a multicenter prospective cohort study. The study included consecutive eligible apixaban- or warfarin-treated patients with non-valvular AF and renal impairment (estimated glomerular filtration rate [eGFR] modification of diet in renal disease [MDRD] < 60 ml/min/BSA) were registered. All patients were prospectively followed for clinical events and over a mean period of 1 year. Our sub-analysis included the patients with 15 < eGFR MDRD < 30 ml/min/BSA. The primary outcomes at 1 year were recorded. They included mortality, stroke or systemic embolism, major bleeding, and myocardial infarction as well as their composite occurrence.

RESULTS

The sub-analysis included 155 warfarin-treated patients and 97 apixaban-treated ones. All had 15 < eGFR MDRD < 30 ml/min/BSA. When comparing outcomes for propensity matched groups (n=76 per group) of patients treated by reduced dose apixaban or warfarin, the rates of the 1-year composite endpoint as well as mortality alone were higher among the warfarin group (30 [39.5%] vs. 14 [18.4%], P = 0.007 and 28 [36.8%] vs.12 [15.8%], P = 0.006), respectively. There was no significant difference in the rates of stroke, systemic embolism, or major bleeding.

CONCLUSIONS

Apixaban might be a reasonable alternative to warfarin in patients with severe renal impairment.

Parathyroidectomy slows renal function decline in patients with primary hyperparathyroidism

PURPOSE

Primary hyperparathyroidism has deleterious effects on health and causes nephrolithiasis and osteoporosis. However, it remains unclear whether parathyroidectomy benefits kidney function among patients with primary hyperparathyroidism.

METHODS

In this retrospective study, patients with primary hyperparathyroidism receiving parathyroidectomy in a tertiary medical center between 2003 and 2017 were followed up until December 31 2017, death, or requiring renal replacement therapy. Impact of parathyroidectomy on kidney function was examined using longitudinal estimated glomerular filtration rate (eGFR) change scales: single, average, absolute difference, percent change, annual decline rate, and slope. We applied linear mixed-effect model to determine the effect of parathyroidectomy on kidney function.

RESULTS

During study period, 167 patients with primary hyperparathyroidism were identified from 498 parathyroidectomized patients, and finally, 27 patients fulfilled our stringent criteria. Median follow-up duration was 1.50 years (interquartile range 1.05-1.81) before surgery and 2.47 years (1.37-6.43) after surgery. Although parathyroidectomy did not affect amount of proteinuria and distribution of eGFR, parathyroidectomy significantly slowed decline rate of eGFR compared with that before surgery (- 1.67 versus - 2.73 mL/min/1.73 m²/year, p < 0.001). More importantly, parathyroidectomy made more beneficial effects on kidney function in patients with age < 65 years and those without chronic kidney disease or hypertension.

CONCLUSIONS

Our study showed that parathyroidectomy slows renal function decline irrespective of age or comorbidities, which offers novel insight into the revision of guidelines for surgical indications in primary hyperparathyroidism. Given small sample size, further large-scale controlled studies are warranted to confirm our findings.

Verification and comparison of three prediction models of ischemic stroke in young adults based on the back propagation neural networks

This work aims to explore risk factors for ischemic stroke in young adults and analyze the Traditional Vascular Risk Factors Model based on age, hypertension, diabetes, smoking history, and drinking history. Further, the Lipid Metabolism Model was analyzed based on lipoprotein a [LP (a)], high-density lipoprotein (HDL), low-density lipoprotein (LDL), apolipoprotein AI (apo AI), apolipoprotein B (apo B), and the Early Renal Injury Model based on urinary microalbuminuria/creatinine ratio (UACR). Besides, we estimated glomerular filtration rate (eGFR), cystatin C (Cys-C), homocysteine (Hcy), β2 microglobulin (β2m), and validated their predictive efficacy and clinical value for the development of ischemic stroke in young adults.We selected and retrospectively analyzed the clinical data of 565 young inpatients admitted to Zhejiang Provincial Hospital of Chinese Medicine between 2010 and 2020, 187 of whom were young stroke patients. A single-factor analysis was used to analyze the risk factors for stroke in young people and developed a traditional vascular risk factors model, a lipid metabolism model, and an early kidney injury model based on backpropagation (BP) neural networks technology to predict early stroke occurrence. Moreover, the prediction performance by the area under the receiver operating characteristics (ROC) curve (AUC) was assessed to further understand the risk factors for stroke in young people and apply their predictive role in the clinical setting.Single-factor analysis showed that ischemic stroke in young adults was associated with hypertension, diabetes, smoking history, drinking history, LP(a), HDL, LDL, apo AI, apo B, eGFR, Cys-C, and β2m (P < .05). The BP neural networks technique was used to plot the ROC curves for the Traditional Vascular Risk Factors Model, the Lipid Metabolism Model, and the Early Kidney Injury Model in enrolled patients, and calculated AUC values of 0.7915, 0.8387, and 0.9803, respectively.The early kidney injury model precisely predicted the risk of ischemic stroke in young adults and exhibited a certain clinical value as a reference for morbidity assessment. Whereas the prediction performance of the Traditional Vascular Risk Factors Model and the Lipid Metabolism Model were inferior to that of the early kidney injury model.

Characteristics and Outcomes of Individuals With Pre-existing Kidney Disease and COVID-19 Admitted to Intensive Care Units in the United States

RATIONALE & OBJECTIVE

Underlying kidney disease is an emerging risk factor for more severe coronavirus disease 2019 (COVID-19) illness. We examined the clinical courses of critically ill COVID-19 patients with and without pre-existing chronic kidney disease (CKD) and investigated the association between the degree of underlying kidney disease and in-hospital outcomes.

STUDY DESIGN

Retrospective cohort study.

SETTINGS & PARTICIPANTS

4,264 critically ill patients with COVID-19 (143 patients with pre-existing kidney failure receiving maintenance dialysis; 521 patients with pre-existing non-dialysis-dependent CKD; and 3,600 patients without pre-existing CKD) admitted to intensive care units (ICUs) at 68 hospitals across the United States.

PREDICTOR(S)

Presence (vs absence) of pre-existing kidney disease.

OUTCOME(S)

In-hospital mortality (primary); respiratory failure, shock, ventricular arrhythmia/cardiac arrest, thromboembolic events, major bleeds, and acute liver injury (secondary).

ANALYTICAL APPROACH

We used standardized differences to compare patient characteristics (values>0.10 indicate a meaningful difference between groups) and multivariable-adjusted Fine and Gray survival models to examine outcome associations.

RESULTS

Dialysis patients had a shorter time from symptom onset to ICU admission compared to other groups (median of 4 [IQR, 2-9] days for maintenance dialysis patients; 7 [IQR, 3-10] days for non-dialysis-dependent CKD patients; and 7 [IQR, 4-10] days for patients without pre-existing CKD). More dialysis patients (25%) reported altered mental status than those with non-dialysis-dependent CKD (20%; standardized difference=0.12) and those without pre-existing CKD (12%; standardized difference=0.36). Half of dialysis and non-dialysis-dependent CKD patients died within 28 days of ICU admission versus 35% of patients without pre-existing CKD. Compared to patients without pre-existing CKD, dialysis patients had higher risk for 28-day in-hospital death (adjusted HR, 1.41 [95% CI, 1.09-1.81]), while patients with non-dialysis-dependent CKD had an intermediate risk (adjusted HR, 1.25 [95% CI, 1.08-1.44]).

LIMITATIONS

Potential residual confounding.

CONCLUSIONS

Findings highlight the high mortality of individuals with underlying kidney disease and severe COVID-19, underscoring the importance of identifying safe and effective COVID-19 therapies in this vulnerable population.

Outcomes Among Patients Hospitalized With COVID-19 and Acute Kidney Injury

RATIONALE & OBJECTIVE

Outcomes of patients hospitalized with coronavirus disease 2019 (COVID-19) and acute kidney injury (AKI) are not well understood. The goal of this study was to investigate the survival and kidney outcomes of these patients.

STUDY DESIGN

Retrospective cohort study.

SETTING & PARTICIPANTS

Patients (aged≥18 years) hospitalized with COVID-19 at 13 hospitals in metropolitan New York between March 1, 2020, and April 27, 2020, followed up until hospital discharge.

EXPOSURE

AKI.

OUTCOMES

Primary outcome: in-hospital death.

SECONDARY OUTCOMES

requiring dialysis at discharge, recovery of kidney function.

ANALYTICAL APPROACH

Univariable and multivariable time-to-event analysis and logistic regression.

RESULTS

Among 9,657 patients admitted with COVID-19, the AKI incidence rate was 38.4/1,000 patient-days. Incidence rates of in-hospital death among patients without AKI, with AKI not requiring dialysis (AKI stages 1-3), and with AKI receiving dialysis (AKI 3D) were 10.8, 31.1, and 37.5/1,000 patient-days, respectively. Taking those without AKI as the reference group, we observed greater risks for in-hospital death for patients with AKI 1-3 and AKI 3D (HRs of 5.6 [95% CI, 5.0-6.3] and 11.3 [95% CI, 9.6-13.1], respectively). After adjusting for demographics, comorbid conditions, and illness severity, the risk for death remained higher among those with AKI 1-3 (adjusted HR, 3.4 [95% CI, 3.0-3.9]) and AKI 3D (adjusted HR, 6.4 [95% CI, 5.5-7.6]) compared with those without AKI. Among patients with AKI 1-3 who survived, 74.1% achieved kidney recovery by the time of discharge. Among those with AKI 3D who survived, 30.6% remained on dialysis at discharge, and prehospitalization chronic kidney disease was the only independent risk factor associated with needing dialysis at discharge (adjusted OR, 9.3 [95% CI, 2.3-37.8]).

LIMITATIONS

Observational retrospective study, limited to the NY metropolitan area during the peak of the COVID-19 pandemic.

CONCLUSIONS

AKI in hospitalized patients with COVID-19 was associated with significant risk for death.

Availability and Affordability of Kidney Health Laboratory Tests around the Globe

BACKGROUND

Kidney disease is a major global public health problem, and laboratory testing of kidney health measures is essential for diagnosis and monitoring. The availability and affordability of kidney health laboratory tests across countries has not been systematically described.

METHODS

The International Society of Nephrology (ISN), in partnership with leaders of a Kidney Disease: Improving Global Outcomes (KDIGO) Controversies Conference, surveyed a representative subset of ISN-Global Kidney Health Atlas (ISN-GKHA) respondents from April to June 2020. We assessed the association between country gross national income (GNI) per capita and laboratory testing availability and affordability.

RESULTS

Of 33 regional expert nephrologists invited, 24 (73%) responded, representing all 10 ISN regions around the world. Availability of kidney health laboratory tests was as follows: serum Cr (100%), serum cystatin C (67%), urine albumin (96%), urine Cr (100%), and dipstick urinalysis (100%). Median (IQR) reimbursement values in international dollars were as follows: serum Cr Int$ 6.61 (3.42-8.84), serum cystatin C Int$ 31.51 (17.36-46.25), urine albumin Int$ 10.22 (5.90-15.42), urine Cr Int$ 7.50 (1.66-8.84), and dipstick urinalysis Int$ 6.26 (2.56-8.40). Reimbursement values did not differ significantly by World Bank income group or by GNI per capita.

CONCLUSION

There was widespread availability of kidney health laboratory tests and substantial variation in reimbursement values. To achieve meaningful progress across nations in mitigating the growth of kidney disease, access to affordable diagnostic technology is essential. Our results are highly relevant to policymakers and researchers as countries increasingly consider national strategies for kidney disease detection and management.

Protective effect of tolvaptan against cyclophosphamide-induced nephrotoxicity in rat models

Cyclophosphamide (CP) is a chemotherapeutic agent which is extensively used in the treatment of multiple neoplastic and nonneoplastic diseases like breast cancer, lymphomas, systemic lupus erythematosus, and multiple sclerosis. Dose-limiting side effects, mainly nephrotoxicity is a major problem hindering its use in the clinical practice. CP induces nephrogenic syndrome of inappropriate antidiuresis mostly via the activation of arginine vasopressin V2 receptors. Moreover, CP produces reactive metabolites which is responsible for augmentation of lipid peroxidation and oxidative stress. Tolvaptan (TOL) is a selective vasopressin V2 receptor antagonist used in the treatment of clinically significant hyponatremia, volume overload in heart failure, and liver cirrhosis with edema. The present study aimed to investigate the potential protective effect of TOL in CP-induced nephrotoxicity. Twenty-four adult male albino rats were randomly divided into four groups: the control group, TOL group that treated daily with tolvaptan (10 mg/kg/d, orally), CP group where CP was administered intraperitoneally 75 mg/kg on days 3, 4, 5, 19, 20, and 21 of study, and the CP + TOL group where animals were treated with TOL daily with (10 mg/kg/d, orally) for 22 days with concomitant administration of CP as described before. Coadministration of TOL with CP induces significant improvement in the level of urine volume, serum Na+, serum osmolarity, urinary creatinine, and free water clearance in addition to significant reduction of body weight, serum creatinine, urea, serum K+, blood pressure, urine osmolarity, and the fractional excretion of sodium as compared to CP-treated group. In addition, coadministration of TOL significantly reduced MDA, the marker of lipid peroxidation, and different pro-inflammatory cytokines. Histopathological changes showed improvement in the signs of nephrotoxicity with the coadministration of TOL. Also, co-treatment with TOL significantly decreased the level of markers of apoptosis as caspase-3 and Bax with increased expression of antiapoptotic Bcl-2 in renal tissue as compared to CP-treated group.

Kidney involvement and associated risk factors in children with Duchenne muscular dystrophy

BACKGROUND

Kidney dysfunction is a common complication in adults with Duchenne muscular dystrophy (DMD); however, little attention has been paid to kidney function in pediatric patients.

METHODS

Medical records of patients with DMD who were followed up for ≥ 12 months were retrospectively reviewed. Inclusion criteria were (i) aged 5-18 years, (ii) proven mutations in the dystrophin gene, and (iii) absence of structural anomalies of the kidney and urinary tract. Serum creatine kinase (CK) was used as an indirect marker of muscle destruction.

RESULTS

Forty-four patients (mean age, 10.9 ± 3.3 years) were included. Blood pressure was evaluated by 24-h ambulatory blood pressure monitoring in 28 patients. Hypertension was found in 9 (32.1%), eight of whom were using steroids. Mild proteinuria, hypercalciuria, hypocalciuria, and hyperphosphaturia in 24-h urine collection (n = 36) were detected in 3 (8.3%), 5 (13.9%), 7 (19.7%), and 6 (16.7%) patients, respectively. Twenty-one (58.3%) demonstrated hyperuricosuria, associated with hyperuricemia in 4. Logarithmic cystatin C (CysC) had a positive correlation to creatinine (Cr) (p = 0.001, r = 0.54), CK (p = 0.048, r = 0.30), and parathormone (PTH) (p = 0.001, r = 0.49). Moreover, the patients were divided into two groups according to median CysC value: group 1 (n = 20, CysC ≤ 0.76 mg/l) and group 2 (n = 24, CysC > 0.76 mg/l). Mean CK, PTH, and Cr levels were significantly elevated in group 2 compared with group 1 (p = 0.010, 0.033, and 0.023, respectively).

CONCLUSIONS

Long-term exposure to the excessive burden of intracellular components released from damaged muscles may be associated with an increased risk over time of chronic kidney impairment in pediatric DMD patients. Graphical abstract.

Patterns of Cystatin C Uptake and Use Across and Within Hospitals

OBJECTIVE

To characterize the use of cystatin C (cysC) across and within hospitals.

PATIENTS AND METHODS

This 2-part study first evaluated access to cysC testing across 129 hospitals in the state of Minnesota, using a telephone-based survey. Second, granular data from a single center (Mayo Clinic) with on-site, rapid-turnaround testing (<1 day) and automated estimated glomerular filtration rate (eGFR) reporting was used to describe temporal patterns. The characteristics of hospitals that offered cysC testing and of patients who underwent rapid cysC testing at Mayo Clinic between January 1, 2011, and March 31, 2018, were described. Poisson regression analyzed temporal trends in cysC testing.

RESULTS

Of the 114 hospitals (88%) that responded to the statewide survey, cysC was available in 91 (80%), but only 3 of 91 (3%) reported a turnaround time of <1 day. At Mayo Clinic, cysC use increased from 0.74 tests per 1000 patient-days in 2011 to 14 tests per 1000 patient-days in 2018 (P=.004). Of the 3774 patients with cysC tests, the mean first available eGFR was 46 mL/min per 1.73 m2 using cysC and 59 mL/min per 1.73 m2 using serum creatinine (P<.001). CysC testing was used across all intensities of care and was ordered by a variety of specialties. Nephrology was consulted in only 42% of cases.

CONCLUSION

In the hospital, rapid-turnaround cysC testing is necessary for practical use but was not widely available in Minnesota. When available, a marked increase in cysC testing was observed over the study timeframe. Additional research is needed to determine optimal strategies for implementation of cysC within hospitals.

The prescription of direct oral anticoagulants in the elderly: An observational study of 19 798 Ambulatory subjects

OBJECTIVE

Direct oral anticoagulants (DOACs) are increasingly prescribed to elderly people, but the epidemiologic data for this population remains scarce. We compared the elderly population taking DOACs and those not taking DOACs (noDOAC).

METHOD

We included individuals over 75 years old, affiliated to Mutualité Sociale Agricole of Burgundy (a French regional health insurance agency), who had been refunded for a prescribed DOAC between 1st and 30th September 2017. The DAOC group (DAOCG) and noDOAC group (noDOACG) were compared in terms of demographic conditions, registered chronic diseases (RCD), and number and types of prescribed drugs. In the DOACG, we compared the type of prescribing physician and laboratory monitoring for novel prescriptions (initial) and prescription refills (≥ 3 months).

RESULTS

Of the 19 798 included patients, 1518 (7.7%) were prescribed DAOCs and 18 280 (92.3%) were not. Mean and median age was 85 years in the 2 groups (DOACG and noDOACG). In the DOACG, there were more men (50% vs 40.2%), more RCD (88.9% vs 68.7%) and more drugs per prescription (6 ± 2.8 vs 5 ± 2.9) (All P < .01). The DOACG also took more antihypertensive drugs. The most commonly prescribed DOACs were apixaban (42.9%) followed by rivaroxaban (38.4%) and dabigatran (18.6%). Complete blood count, serum creatinine and coagulation function tests were requested for 69.4%, 75% and 22.2%, respectively, of patients prescribed DAOCs.

CONCLUSIONS

The DOACG had more RCD and drugs per prescription than the noDOACG; routine laboratory monitoring was insufficient. What's known Platelet aggregation inhibitors (low-dose) are recommended for secondary prevention of cardiovascular events in patients suffering from symptomatic atherosclerosis. The main risk of this treatment is bleeding. What's new A prescription for platelet aggregation inhibitors was found in 34% of geriatric inpatients in this prospective study. Compliance to guidelines was better for symptomatic peripheral artery disease than for primary prevention in accordance with recent publications. Geriatric comorbidities had no impact on the prescription of platelet aggregation inhibitors. Underuse of platelet aggregation inhibitors was observed in 11.3% of cases and overuse in 13.7% of cases.

Impact of Severity of Chronic Kidney Disease on Management and Outcomes Following Transcatheter Aortic Valve Replacement With Newer-Generation Transcatheter Valves

BACKGROUND

The association between chronic kidney disease (CKD) and outcomes following transcatheter aortic valve replacement (TAVR) in the setting of newer-generation transcatheter heart valves (THVs) is not well known. Accordingly, we sought to assess the impact of CKD severity on outcomes in adults undergoing TAVR with newer-generation THVs.

METHODS

The study population included 298 consecutive patients who underwent TAVR with a newer-generation THV (Sapien 3 [Edwards Lifesciences] or CoreValve Evolut R or Evolut Pro [Medtronic]) from December 2015 to June 2018 at an academic tertiary medical center. Patients were classified into three groups: group I, defined as creatinine clearance (CrCl) ≥60 mL/ min (n = 133); group II, defined as CrCl ≥30 mL/min and <60 mL/min (n = 128); and group III, defined as CrCl <30 mL/min (n = 37).

RESULTS

Median length of stay was longer in groups II and III (2.0 days in group I vs 3.0 days in group II vs 4.0 days in group III; P<.01). While rates of 30-day readmission were significantly higher in groups II and III compared with group I (14.5% in group I vs 26.6% in group II vs 37.1% in group III; P<.01), rates of in-hospital and 30-day mortality and disabling stroke were similar. In multivariable analysis, CKD was independently associated with higher 30-day readmission rates (group II: odds ratio, 2.10; 95% confidence interval 1.02-4.32; group III: odds ratio, 3.52; 95% confidence interval, 1.40-8.87; group I: referent).

CONCLUSIONS

In this prospective study of adults undergoing TAVR with newer-generation THVs, moderate and severe CKD was associated with a nearly 2-fold and 3-fold higher risk of 30-day readmission, respectively.

Chronic kidney disease and socio-economic status: a cross sectional study

Objective: This cross-sectional study investigated the relationship between individual-level markers of disadvantage, renal function and cardio-metabolic risk within an Indigenous population characterised by a heavy burden of chronic kidney disease and disadvantage.Design: Using data from 20 Indigenous communities across Australia, an aggregate socio-economic status (SES) score was created from individual-level socio-economic variables reported by participants. Logistic regression was used to assess the association of individual-level socio-economic variables and the SES score with kidney function (an estimated glomerular function rate (eGFR) cut-point of <60 ml/min/1.73 m²) as well as clinical indicators of cardio-metabolic risk.Results: The combination of lower education and unemployment was associated with poorer kidney function and higher cardio-metabolic risk factors. Regression models adjusted for age and gender showed that an eGFR < 60 ml/min/1.73 m² was associated with a low socio-economic score (lowest vs. highest 3.24 [95% CI 1.43-6.97]), remote living (remote vs. highly to moderately accessible 3.24 [95% CI 1.28-8.23]), renting (renting vs. owning/being purchased 5.76[95% CI 1.91-17.33]), unemployment (unemployed vs employed 2.85 [95% CI 1.31-6.19]) and receiving welfare (welfare vs. salary 2.49 [95% CI 1.42-4.37]). A higher aggregate socio-economic score was inversely associated with an eGFR < 60 ml/min/1.73 m² (0.75 [95% CI 063-0.89]).Conclusion: This study extends upon our understanding of associations between area-level markers of disadvantage and burden of end stage kidney disease amongst Indigenous populations to a detailed analysis of a range of well-characterised individual-level factors such as overall low socio-economic status, remote living, renting, unemployment and welfare. With the increasing burden of end-stage kidney disease amongst Indigenous people, the underlying socio-economic conditions and social and cultural determinants of health need to be understood at an individual as well as community-level, to develop, implement, target and sustain interventions.

Clinical Characteristics of and Risk Factors for Chronic Kidney Disease Among Adults and Children: An Analysis of the CURE-CKD Registry

IMPORTANCE

Chronic kidney disease (CKD) is serious and common, yet recognition and public health responses are limited.

OBJECTIVE

To describe clinical features of, prevalence of, major risk factors for, and care for CKD among patients treated in 2 large US health care systems.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study collected data from the Center for Kidney Disease Research, Education, and Hope (CURE-CKD) registry, an electronic health record-based registry jointly curated and sponsored by Providence St Joseph Health and the University of California, Los Angeles. Patients were adults and children with CKD (excluding end-stage kidney disease) and adults at risk of CKD (ie, with diabetes, hypertension, or prediabetes) identified by laboratory values, vital signs, prescriptions, and administrative codes. Data were collected from January 2006 through December 2017, with analyses performed from March 2019 through November 2019.

EXPOSURES

Diabetes, hypertension, and prediabetes.

MAIN OUTCOMES AND MEASURES

Clinical and demographic characteristics, prevalence, and prescribed medications.

RESULTS

Of 2 625 963 adults and children in the sample, 606 064 adults (23.1%) with CKD had a median (interquartile range [IQR]) age of 70 (59-81) years, with 338 785 women (55.9%) and 434 474 non-Latino white individuals (71.7%). A total of 12 591 children (0.4%) with CKD had a median (IQR) age of 6 (1-13) years, with 7079 girls (56.2%) and 6653 non-Latino white children (52.8%). Median (IQR) estimated glomerular filtration rate was 53 (41-61) mL/min/1.73 m2 among adults and 70 (50-95) mL/min/1.73 m2 in children. Prevalence rates for CKD in adults were 4.8% overall (606 064 of 12 669 700) with 1.6% (93 644 of 6 011 129) during 2006 to 2009, 5.7% (393 455 of 6 903 084) during 2010 to 2013, and 8.4% (683 574 of 8 179 860) during 2014 to 2017 (P < .001). A total of 226 693 patients (37.4%) had category 3a CKD; 100 239 (16.5%), category 3b CKD; 39 125 (6.5%), category 4 CKD; and 20 328 (3.4%), category 5 CKD. Among adults with CKD, albuminuria and proteinuria assessments were available in 52 551 (8.7%) and 25 035 (4.1%) patients, respectively. A renin-angiotensin system inhibitor was prescribed to 124 575 patients (20.6%), and 204 307 (33.7%) received nonsteroidal anti-inflammatory drugs or proton pump inhibitors. Of 1 973 258 adults (75.1%) at risk, one-quarter had diabetes or prediabetes (512 299 [26.0%]), nearly half had hypertension (955 812 [48.4%]), and one-quarter had both hypertension and diabetes or prediabetes (505 147 [25.6%]).

CONCLUSIONS AND RELEVANCE

This registry-based cohort study revealed a burgeoning number of patients with CKD and its major risk factors. Rates of identification and use of kidney protective agents were low, while potential nephrotoxin use was widespread, underscoring the pressing need for practice-based improvements in CKD prevention, recognition, and treatment.

Prevalence of chronic kidney disease in the elderly using the ASPirin in Reducing Events in the Elderly study cohort

AIM

The prevalence of chronic kidney disease (CKD) in the elderly is controversial because age-related decline in kidney function may not truly reflect underlying kidney disease. We estimate the baseline prevalence and predictors of CKD using the CKD Epidemiology Collaboration (CKD-EPIeGFR ) and Berlin Initiative Study 1 (BIS1eGFR ) eGFR equations in the ASPirin in Reducing Events in the Elderly (ASPREE) trial cohort of healthy older participants.

METHODS

GFR was estimated using CKD-EPI and BIS1 equations. CKD was defined as eGFR <60 mL/min/1.73 m2 or ≥ 60 mL/min/1.73 m2 with urine albumin creatinine ratio (UACR) ≥ 3 mg/mmol. Logistic regression was used to identify predictors of CKD prevalence defined by each eGFR equation.

RESULTS

Data for analysis were complete for 17,762 participants. Mean age was 75.1 years (SD 5); 56.4% were female, 76.4% had hypertension, 9% had diabetes mellitus. Mean CKD-EPIeGFR was 73.0 (SD 14.2), compared with mean BIS1eGFR of 62.7 (11.4). Median UACR was 0.8 (IQR 0.5, 1.5) mg/mmol. Prevalence of CKD by CKD-EPIeGFR was 27% (predominantly due to normoalbuminuric stage 3a CKD), substantially lower than 47.1% by BIS1eGFR ; the difference was predominantly driven by reclassification of individuals from G1 and G2 CKD to stage G3a without albuminuria. Increased prevalence of CKD by either equation was related to older age, hypertension, diabetes, or higher body mass index.

CONCLUSIONS

Prevalence of CKD with CKD-EPIeGFR was 27%, and doubled using the elderly specific BIS1eGFR , with most participants reclassified from stage 2 to stage 3a. Increased prevalence of CKD was related older age, hypertension, diabetes, or increased body mass index.

Lab monitoring and acute care utilization during initiation of renin angiotensin aldosterone inhibitors or diuretics in chronic kidney disease

Renin angiotensin aldosterone system inhibitors (RAASi) and diuretics are among the most frequently prescribed anti-hypertensives. Individuals with chronic kidney disease (CKD) are particularly at risk for electrolyte disturbances and kidney injury but the appropriate use of lab monitoring following RAASi or diuretic initiation is uncertain in CKD.We describe the frequency and time interval of lab monitoring during initiation of RAASi and diuretics in CKD and assess whether close lab monitoring associates with one-year risk of emergency department (ED) visit or hospitalization.We evaluated an observational cohort of 8,217 individuals with stage 3-5 non-dialysis CKD newly prescribed a RAASi (52.3%) or diuretic (47.7%) from thirty-six primary care offices affiliated with Brigham and Women's Hospital and Massachusetts General Hospital between 2009 and 2011.Overall, 3306 (40.2%) individuals did not have pre-prescription labs done within 2 weeks, and 5957 (72.5%) did not have post-prescription labs done within 2 weeks which includes 524 (6.4%) individuals without post-prescription within 1 year. Close monitoring occurred in only 1547 (20.1%) and was more likely in individuals prescribed diuretics compared to RAASi (adjusted OR 1.39; 95%CI 1.20-1.62), with CKD stage 4,5 compared with stage 3 (adjusted OR 1.47; 95%CI 1.16-1.86) and with cardiovascular disease (adjusted OR 1.42; 95%CI 1.21-1.66). Close monitoring was not associated with decreased risk of ED visit or hospitalization.Close lab monitoring during initiation of RAASi or diuretics was more common in participants with cardiovascular disease and advanced CKD suggesting physicians selected high-risk individuals for close monitoring. As nearly 80% of individuals did not receive close lab monitoring there may be value in future research on electronic physician decision tools targeted at lab monitoring.

Trends in kidney function testing in UK primary care since the introduction of the quality and outcomes framework: a retrospective cohort study using CPRD

OBJECTIVES

To characterise serum creatinine and urinary protein testing in UK general practices from 2005 to 2013 and to examine how the frequency of testing varies across demographic factors, with the presence of chronic conditions and with the prescribing of drugs for which kidney function monitoring is recommended.

DESIGN

Retrospective open cohort study.

SETTING

Routinely collected data from 630 UK general practices contributing to the Clinical Practice Research Datalink.

PARTICIPANTS

4 573 275 patients aged over 18 years registered at up-to-standard practices between 1 April 2005 and 31 March 2013. At study entry, no patients were kidney transplant donors or recipients, pregnant or on dialysis.

PRIMARY OUTCOME MEASURES

The rate of serum creatinine and urinary protein testing per year and the percentage of patients with isolated and repeated testing per year.

RESULTS

The rate of serum creatinine testing increased linearly across all age groups. The rate of proteinuria testing increased sharply in the 2009-2010 financial year but only for patients aged 60 years or over. For patients with established chronic kidney disease (CKD), creatinine testing increased rapidly in 2006-2007 and 2007-2008, and proteinuria testing in 2009-2010, reflecting the introduction of Quality and Outcomes Framework indicators. In adjusted analyses, CKD Read codes were associated with up to a twofold increase in the rate of serum creatinine testing, while other chronic conditions and potentially nephrotoxic drugs were associated with up to a sixfold increase. Regional variation in serum creatinine testing reflected country boundaries.

CONCLUSIONS

Over a nine-year period, there have been increases in the numbers of patients having kidney function tests annually and in the frequency of testing. Changes in the recommended management of CKD in primary care were the primary determinant, and increases persist even after controlling for demographic and patient-level factors. Future studies should address whether increased testing has led to better outcomes.

Circulating leptin levels predict the decline in renal function with age in a sample of adult men (The Olivetti Heart Study)

Leptin (LPT) is associated with a number of cardiovascular risk factors, such as high blood pressure (BP), insulin resistance and excess in body weight. Some studies find an unfavorable cross-sectional association between LPT and renal disease, in particular in patients with already known kidney dysfunction. There are few data on the relationship between LPT and changes in renal function over time in subjects without evidence of kidney dysfunction. Hence, the aim of this study is to estimate the predictive role of LPT on the decline in renal function occurring in an 8-year follow-up observation of a sample of adult apparently healthy men (The Olivetti Heart Study). The study includes 319 untreated normotensive and nondiabetic men without clinical evidence of renal dysfunction (creatinine clearance-CrCl > 60 mL/min/1.73 m²) at baseline. At baseline, LPT is significantly and positively associated with BMI, abdominal circumference, BP and Homa index, no relationship is found with CrCl. At the end of the 8-year follow-up, a significant association is detected between baseline LPT and changes occurring in BP. Moreover, an inverse correlation with changes in CrCl is found (r = - 0.12). This unfavorable relationship between baseline LPT and decline in renal function is also confirmed in the multivariate analyses, after adjustment for all potential confounders (R² = 0.42, p < 0.01). The results of this prospective investigation suggest a predictive role of circulating LPT levels on decline in renal function over time, independently of main potential confounders, in normotensive and nondiabetic men with normal renal function at baseline.

Urinary uromodulin independently predicts end-stage renal disease and rapid kidney function decline in a cohort of chronic kidney disease patients

Data on risk factors predicting rapid progression to end-stage renal disease (ESRD) or short-term kidney function decline (i.e., within 1 year) in chronic kidney disease (CKD) are rare but urgently needed to plan treatment. This study describes the association and predictive value of urinary uromodulin (uUMOD) for rapid progression of CKD.We assessed uUMOD, demographic/treatment parameters, estimated glomerular filtration rate (eGFR), and proteinuria in 230 CKD patients stage I-V. ESRD and 25% decline of eGFR was documented at the end of follow-up period and used as a composite endpoint. Association between logarithmic uUMOD and eGFR/proteinuria was calculated using linear regression analysis, adjusting for age, gender, and body mass index. We performed multivariable Cox proportional hazard regression analysis to evaluate the association of uUMOD with the composite endpoint. Therefore, patients were categorized into quartiles. The predictive value of uUMOD for the above outcomes was assessed using receiver-operating characteristic (ROC) curve analysis.Follow-up was 57.3 ± 18.7 weeks, baseline age was 60 (18;92) years, and eGFR was 38 (6;156) mL/min/1.73 m. Forty-seven (20.4%) patients reached the composite endpoint. uUMOD concentrations were directly associated with eGFR and inversely associated with proteinuria (β = 0.554 and β = -0.429, P < .001). In multivariable Cox regression analysis, the first 2 quartiles of uUMOD concentrations had a hazard ratio (HR) of 3.589 [95% confidence interval (95% CI) 1.002-12.992] and 5.409 (95% CI 1.444-20.269), respectively, in comparison to patients of the highest quartile (≥11.45 μg/mL) for the composite endpoint. In ROC-analysis, uUMOD predicted the composite endpoint with good sensitivity (74.6%) and specificity (76.6%) at an optimal cut-off at 3.5 μg/mL and area under the curve of 0.786 (95% CI 0.712-0.860, P < .001).uUMOD was independently associated with ESRD/rapid loss of eGFR. It might serve as a robust predictor of rapid kidney function decline and help to better schedule arrangements for future treatment.

Prediction of acute kidney injury: the ratio of renal resistive index to semiquantitative power Doppler ultrasound score-a better predictor?: A prospective observational study

This study aimed to explore the diagnostic performance of the ratio of renal resistive index (RRI) to semiquantitative power Doppler ultrasound (PDU) score in predicting acute kidney injury (AKI) 3 in critically ill patients.This study was a prospective, observational study that included 101 critically ill patients. RRI and semiquantitative PDU score were measured within 6 hours following admission to the intensive care unit (ICU). The ratio of RRI to PDU (RRI/PDU) was calculated as follows: RRI / PDU. If PDU score was 0, the RRI/PDU was 1. Meanwhile, AKI was defined according to the Kidney Disease Improving Global Outcomes criteria.Median RRI/PDU was 0.234 (0.190, 0.335) in patients with AKI 0-2 and 0.636 (0.411, 0.738) in patients with AKI 3 (P < .001). As assessed by the area under the receiver operator characteristic curves (AUC), RRI/PDU performed best in diagnosing AKI 3 [AUC = 0.935 (95% CI: 0.868-0.974)]. Optimal cuto for RRI/PDU was > 0.37, and the sensitivity and specificity were 90.5% and 90.0%, respectively. In 93 patients, except for 8 patients with a PDU score of 0, the AUC of RRI/PDU [0.938 (95% CI: 0.868-0.977)] was superior to the PDU score (0.905 [95% CI: 0.826-0.956], P = .133), RRI [0.782 (95% CI: 0.684-0.861), P = .016], serum creatinine [0.801 (95% CI: 0.705-0.877), P = .017], or 6 hours AKI stage (0.876 [95% CI: 0.791-0.935], P = .110) in predicting AKI 3 on D5.In our study, RRI, PDU score, RRI/PDU, and 6 hours AKI stage were useful in predicting AKI 3. Furthermore, RRI/PDU may be a better predictor of AKI 3.

Prevalence and factors associated with renal dysfunction in children admitted to two hospitals in northwestern Tanzania

BACKGROUND

It is evident that renal dysfunction (RD) is associated with unique infectious and non-infectious causes in African children. However, little data exists about the prevalence and factors associated with RD in children admitted to African hospitals.

METHODS

In this cross-sectional study, we enrolled all children admitted to pediatric wards of Bugando Medical Centre (BMC) and Sekou-Toure Regional Referral hospital (SRRH) during a 6 month time period. Socio-demographical, clinical and laboratory data were collected using a structured questionnaire. Estimated glomerular filtration rate (eGFR) was calculated using modified Schwartz equation and those with < 60 ml/min/1.73m2were considered to have RD. Data analysis was done using STATA version 13 and considered significant when p-value was < 0.05.

RESULTS

A total of 513 children were enrolled, of which 297 (57.9%) were males. Median age of children with and without RD was 34 months (27-60) and 46.5 (29-72) respectively. Prevalence of RD was 16.2%. Factors associated with RD were herbal medication use (p = 0.007), history of sore throat or skin infection (p = 0.024), sickle cell disease (SCD) (p = 0.006), dehydration (p = 0.001), malaria (p = 0.01) and proteinuria (p = < 0.001).

CONCLUSIONS

High prevalence of RD was observed among children admitted to referral hospitals in Mwanza. Screening for RD should be performed on admitted children, particularly those with history of herbal medication use, sore throat/skin infection, SCD, dehydration and malaria. Where creatinine measurement is not possible, screening for proteinuria is a reasonable alternative.

Development of an electronic health record-based chronic kidney disease registry to promote population health management

BACKGROUND

Electronic health record (EHR) based chronic kidney disease (CKD) registries are central to population health strategies to improve CKD care. In 2015, Partners Healthcare System (PHS), encompassing multiple academic and community hospitals and outpatient care facilities in Massachusetts, developed an EHR-based CKD registry to identify opportunities for quality improvement, defined as improvement on both process measures and outcomes measures associated with clinical care.

METHODS

Patients are included in the registry based on the following criteria: 1) two estimated glomerular filtration rate (eGFR) results < 60 ml/min/1.73m2 separated by 90 days, including the most recent eGFR being < 60 ml/min/1.73m2; or 2) the most recent two urine protein values > 300 mg protein/g creatinine on either urine total protein/creatinine ratio or urine albumin/creatinine ratio; or 3) an EHR problem list diagnosis of end stage renal disease (ESRD). The registry categorizes patients by CKD stage and includes rates of annual testing for eGFR and proteinuria, blood pressure control, use of angiotensin converting enzyme inhibitors (ACE-Is) or angiotensin receptor blockers (ARBs), nephrotoxic medication use, hepatitis B virus (HBV) immunization, vascular access placement, transplant status, CKD progression risk; number of outpatient nephrology visits, and hospitalizations.

RESULTS

The CKD registry includes 60,503 patients and has revealed several opportunities for care improvement including 1) annual proteinuria testing performed for 17% (stage 3) and 31% (stage 4) of patients; 2) ACE-I/ARB used in 41% (stage 3) and 46% (stage 4) of patients; 3) nephrotoxic medications used among 23% of stage 4 patients; and 4) 89% of stage 4 patients lack HBV immunity. For advanced CKD patients there are opportunities to improve vascular access placement, transplant referrals and outpatient nephrology contact.

CONCLUSIONS

A CKD registry can identify modifiable care gaps across the spectrum of CKD care and enable population health strategy implementation. No linkage to Social Security Death Master File or US Renal Data System (USRDS) databases limits our ability to track mortality and progression to ESRD.

Dose adjustment of metformin and dipeptidyl-peptidase IV inhibitors in diabetic patients with renal dysfunction

OBJECTIVES

This analysis of real-world data aimed to (a) determine the proportion of Type II diabetes (T2DM) patients treated with metformin or dipeptidyl peptidase-4 inhibitors (DPP-4i) that require dose adjustment or therapy discontinuation due to chronic kidney disease (CKD), and (b) to assess the time required to dose adjustment from the time of worsening of CKD.

METHODS

In this retrospective study, two study populations were defined in a large healthcare organization. In the cross-sectional analysis, the distribution of CKD stages and the appropriate dosage of metformin and DPP-4i in 2013 was examined according to renal function among T2DM patients. In the longitudinal analysis, a cohort was defined to assess the time elapsed from first indication worsening of CKD to dose adjustment, among patients treated with those medications during years 2006-2013.

RESULTS

Among patients treated with metformin or DPP-4i, one third of patients with CKD failed to adjust the dosage or to discontinue metformin or DPP-4i as indicated. Median time for dose adjustment or discontinuation was significantly longer for DPP-4i than for metformin (9.8 compared to 16.8 months for metformin and DPP-4i, respectively; p-value <.001).

CONCLUSIONS

This real-world data analysis showed that adjustment of dose or discontinuation of metformin or DPP-4i in patients with worsening CKD occurred less often in DPP-4i users than metformin users and took a longer time.

Test-retest reliability and minimal detectable change scores for the short physical performance battery, one-legged standing test and timed up and go test in patients undergoing hemodialysis

Functional tests are commonly used for chronic kidney disease (CKD) patients undergoing hemodialysis (HD). However, the relative and absolute reliability of such physical performance-outcome assessments must first be determined in specific patient cohorts. The aims of this study were to assess the relative and the absolute reliability of the Short Physical Performance Battery (SPPB), One-Legged Stance Test (OLST), and Timed Up and Go (TUG) test, as well as the minimal detectable change (MDC) scores for these tests in CKD patients receiving HD. Seventy-one end-stage CKD patients receiving HD therapy, aged between 21 and 90 years, participated in the study. The patients completed two testing sessions one to two weeks apart and performed by the same examiner, comprising the following tests: the SPPB (n = 65), OLST (n = 62), and TUG test (n = 66). High intraclass correlation coefficients (≥0.90) were found for all the tests, suggesting that their relative reliability is excellent. The MDC scores for the 90% confidence intervals were as follows: 1.7 points for the SPPB, 11.3 seconds for the OLST, and 2.9 seconds for the TUG test. The reliability of the SPPB, OLST, and TUG test for this sample were all considered to be acceptable. The MDC data generated by these tests can be used to monitor meaningful changes in the functional capacity of the daily living-related activity of CKD patients on HD.

Impact of dialysis dependence on prognosis in patients with myocardial infarction: An 11-year population-based study

In this study we aimed to directly compare the short and long-term prognosis of nondialysis patients with chronic kidney disease (CKD), dialysis patients, and patients with preserved renal function after acute myocardial infarction (AMI).AMI in patients with CKD is a catastrophic event associated with high medical expenditures and dismal survival. However, there is little research comparing post-AMI outcomes between patients with CKD who were and were not receiving dialysis.The retrospective cohort study included patients with AMI (n = 158,125) in the Taiwan's National Health Insurance Research Database who were treated March 1998 and December 2009. Patients were classified into a nondialysis CKD group (n = 6300), dialysis group (n = 5140), and a control group (n = 146,685). The clinical characteristics, in-hospital events, and long-term outcomes of these 3 groups were compared separately using a multivariable Cox proportional hazard model.The risks of in-hospital death and 2-year all-cause mortality were the highest in the dialysis group, followed by the nondialysis CKD group, and were the lowest in the control group. The 1-year risk of myocardial infarction did not differ among the 3 study groups, but the 2-year risk of myocardial infarction was higher in the dialysis group than in the control group (hazard ratio, 1.13; 95% confidence interval, 1.03-1.24; P = .010).Patients with CKD experienced adverse short- and long-term outcomes after acute myocardial infarction. Patients with CKD, especially those who are dialysis dependent, may require more intensive management to improve their post-AMI clinical outcomes.

Comparison of changes in renal function with dosimetric parameters in gastric cancer patients treated with adjuvant chemoradiotherapy

PURPOSE

Our objective was to analyze kidney damage using glomerular filtration rate (GFR) and dynamic renal scintigraphy (DRS) compared with dose volume histogram (DVH) parameters in gastric cancer patients.

MATERIALS AND METHODS

Twenty-two gastric cancer patients treated with postoperative chemoradiotherapy were retrospectively evaluated. Student's t test was used to compare pre- and posttreatment GFR and creatinine values. The relative contribution of the left and right kidney in DRS results was expressed as left-to-right ratio (L/R), and the percentage of initial and control participation ratio difference was calculated. Spearman's correlation analysis was used to compare the percentage difference of L/R ratio with DVH parameters of each kidney.

RESULTS

In DRS analysis, decrease in left kidney cortical function was observed in one patient. V5-V10 of the left and bilateral kidneys were significantly associated with GFR decline. None of the DVH parameter was significantly associated with L/R ratio. However, the V15 and D_mean of the bilateral kidney were significantly correlated with greater decrease in L/R ratio in seven patients whose posttreatment DRS period was > 12 months.

CONCLUSIONS

Decline in renal function, even with current renal constraints, was observed. Minimization of V5, V10, and V15 and mean dose (D_mean) to the kidney should be considered.

Community burden and prognostic impact of reduced kidney function among patients hospitalized with acute decompensated heart failure: The Atherosclerosis Risk in Communities (ARIC) Study Community Surveillance

Background

Kidney dysfunction is prevalent and impacts prognosis in patients with acute decompensated heart failure (ADHF). However, most previous reports were from a single hospital, limiting their generalizability. Also, contemporary data using new equation for estimated glomerular filtration rate (eGFR) are needed.

Methods and results

We analyzed data from the ARIC Community Surveillance for ADHF conducted for residents aged ≥55 years in four US communities between 2005–2011. All ADHF cases (n = 5, 391) were adjudicated and weighted to represent those communities (24,932 weighted cases). The association of kidney function (creatinine-based eGFR by the CKD-EPI equation and blood urea nitrogen [BUN]) during hospitalization with 1-year mortality was assessed using logistic regression. Based on worst and last serum creatinine, there were 82.5% and 70.6% with reduced eGFR (<60 ml/min/1.73m²) and 37.4% and 26.6% with severely reduced eGFR (<30 ml/min/1.73m²), respectively. Lower eGFR (regardless of last or worst eGFR), particularly eGFR <30 ml/min/1.73m², was significantly associated with higher 1-year mortality independently of potential confounders (odds ratio 1.60 [95% CI 1.26–2.04] for last eGFR 15–29 ml/min/1.73m² and 2.30 [1.76–3.00] for <15 compared to eGFR ≥60). The association was largely consistent across demographic subgroups. Of interest, when both eGFR and BUN were modeled together, only BUN remained significant.

Conclusions

Severely reduced eGFR (<30 ml/min/1.73m²) was observed in ~30% of ADHF cases and was an independent predictor of 1-year mortality in community. For prediction, BUN appeared to be superior to eGFR. These findings suggest the need of close attention to kidney dysfunction among ADHF patients.

The association between urbanization and reduced renal function: findings from the China Health and Nutrition Survey

BACKGROUND

While chronic kidney disease (CKD) is a growing public health concern in low- and middle-income countries, such as China, few studies have investigated the association between urbanization and the occurrence of CKD in those countries.

METHODS

We investigated the association between urbanization and estimated glomerular filtration rate (eGFR), an important CKD risk marker. Data came from the China Health and Nutrition Survey wave 2009, in which we collected fasting serum, individual and household data along with community level urbanization data, which was used to derive a study-specific urbanization measure, in 218 communities across nine provinces. A total of 3644 men and 4154 women participants aged 18 years or older were included in the analysis. Reduced renal function was defined as eGFR of less than 60 mL/min/1.73 m2 measured using serum creatinine concentration (mg/dL).

RESULTS

After adjusting for socio-demographic (e.g., age, education and household income), a sex-stratified multilevel logistic model revealed that living in a more urbanized community was associated with higher odds of reduced eGFR (odds ratio [OR] = 1.38 per one-standard deviation [SD] increase in the CHNS specific urbanization index, 95% confidence interval [CI] = 1.11-1.73 for men; OR = 1.35, 95% CI = 1.11-1.62 for women). After adjusting for behavioral variables (i.e., alcohol consumption, smoking, physical activity and diet), as well as obesity and cardiometabolic risk factors, the association was attenuated in men (OR = 1.25, 95% CI = 0.98-1.59), but remained statistically significant in women (OR = 1.24, 95% CI = 1.01-1.52).

CONCLUSION

Our findings suggest that living in an urban environment is linked with higher odds of reduced renal function independently of behavioral and cardiometabolic risk factors, which have been shown to increase along with urbanization.

Chronic kidney disease in primary care

It has been estimated that chronic kidney disease (CKD) affects about one in 200 of the population in the UK. There is an increased awareness of the need to identify patients in primary care with CKD at an earlier stage, so that treatments can be initiated to delay progression and prevent complications and appropriate nephrological referral can be made. In this article we will review how measures to identify patients with CKD can improve its management.

Clinical predictors of diagnostic testing utility in the initial evaluation of chronic kidney disease

AIM

No evidence-based approach to the evaluation of CKD has been established. We sought to identify clinical criteria to guide a rational diagnostic approach for the initial evaluation of CKD.

METHODS

We conducted a retrospective cohort study of 1487 patients presenting for initial evaluation of CKD over 3 years (1/2010-1/2013) to academic nephrology clinics. We utilized the electronic medical record to determine tests ordered, abnormal results and testing that affected diagnosis and/or management. Diagnostic and management yield of testing was defined as the percentage of tests that affected diagnosis and/or management. High yield for a given test was defined as an increased likelihood of the test affecting diagnosis and/or management.

RESULTS

We identified clinical criteria predictive of high yield for paraprotein-related testing (one of the following: history of monoclonal disease, high risk of CKD progression, hypercalcemia or haemoglobin < 10.6), and clinical criteria predictive of high yield for glomerulonephritis testing (one of the following: abnormal urine sediment, 3+ or greater hematuria or proteinuria > 500 mg/gm). A prior history of hydronephrosis and renal artery stenosis was predictive of high yield of abnormal renal ultrasound. Higher yield of testing was associated with higher risk progression categories for ANA, SPEP, urine sediment, calcium, PTH, haemoglobin, iron and ferritin. We estimate that initial CKD evaluation costs range from $28 to $109 million/year in US-Medicare expenditure.

CONCLUSION

Numerous tests without significant clinical utility are obtained in initial CKD evaluation. Identifying criteria that can guide diagnostic testing may lead to a more informed and cost-effective approach to evaluation.

The Prevalence of Renal Failure. Results from the German Health Interview and Examination Survey for Adults, 2008-2011 (DEGS1)

BACKGROUND

The prevalence of non-end stage renal failure among adults in Germany is unknown. Accurate figures would enable us to estimate the overall need for kidney replacement therapies and the unexploited potential for disease prevention. Renal failure is also an important cardiovascular risk factor. Until now, American prevalence figures have often been applied to Germany despite dissimilarities between the two populations.

METHODS

We analyzed data on renal function from the nationwide German Health Interview and Examination Survey for Adults, 2008-2011 (DEGS1), which was carried out by the Robert Koch Institute. The glomerular filtration rate was estimated (eGFR) from the serum creatinine and cystatin C levels (CKD-EPI formula) and a semiquantitative measure of albuminuria. Relationships between renal failure and its possible determinants were quantified with adjusted prevalence ratios (PR) and 95% confidence intervals (95% CI).

RESULTS

Roughly 2.3% (95% CI: [1.9; 2.6 ]) of persons aged 18-79 had an eGFR below 60 mL/min/1.73 m2. The prevalence rose with age. We extrapolated these figures conservatively to persons aged 80 and above, who were not included in the DEGS1, and arrived at a figure of at least 2 million persons in Germany with renal failure. 11.5% of the population have albuminuria of at least 30 mg/L. Diabetes mellitus (PR = 2.25, 95% CI: [1.59; 3.16]) and arterial hypertension (PR = 3.46, 95% CI: [1.95; 6.12]) are important determinants.

CONCLUSION

This study provides the first representative estimate of the prevalence of renal failure in Germany. The condition is highly dependent on age but less prevalent than previously assumed on the basis of American prevalence figures.

[State of kidneys of the population of the industrial city]

The assessment of renal functions of the adult population of Atyrau (West Kazakhstan) exposed to Atyrau oil refinery and other industrial objects (enterprises in the city), as well as employees of this refinery has been performed by virtue of the identification ofpathological changes in the urine with the use ofphotometric screening, determination of serum levels of creatinine, urea, uric acid and the calculation of glomerular filtration rate. There were obtained evident data testifying to the development of statistically significant exertion of renal function in residents of this city as compared with those of control area residents. There was revealed a statistically significant decrease in the relative density of urine in in 42% of the population, leucocyturia - in 20%, erythrocyturia - in 25%. Decreased glomerularfiltration rate was noted in these people. A statistically significant elevation of the level of uric acid in the blood in combination with an acidic reaction and sharply acidic urine reaction indicates to the possibility of the development of urate urolithiasis which is confirmed by cases of discharge of stones in the urine in 20% of the population according to data of previously executed questionnaire survey. The above mentioned changes in the functional renal reserve and hyperuricemia are equally often found among the residents of the city - Atyrau refinery workers, and the rest of the city people as well. The results of the study allow to recommend the screening ofurine with quantitative registration ofpathological changes as a mean of the most optimal objective methods for early detection of renal dysfunction in population exposed to nephrotoxic impact of environmental techno-genic pollutants.

Correlation Between Clinicaland Pathological Characteristics of Henoch-Schönlein Purpura Nephritis in Adults

INTRODUCTION

Henoch-Schönlein purpura nephritis (HSPN) mainly affects children and is less common in adults, but its associated pathological changes are severe in adults, in whom it results in a poor prognosis. This study aimed to analyze the clinical and pathological characteristics of HSPN in adults and to identify the correlations among them.

MATERIALS AND METHODS

Clinical and pathological data from139 patients older than 18 years of age who had been diagnosed with HSPN and had received renal biopsy at our center from January 2012 to November 2014 were collected and were grouped according to the different conditions and analyzed retrospectively.

RESULTS

The 139 HSPN patients included 74 men and 65 women, with an average age of 39.17 ± 15.87 years. The pathological grade was IIIa in most of the patients, and moderate proteinuria was the most common clinical type. Kidney failure and 24-hour total urinary protein, serum uric acid, cystatin C, and β2-microglobulin levels were positively correlated with the pathological grade and activity (P < .05). Age, kidney failure, and uric acid were positively correlated with the pathological chronicity (P < .05).

CONCLUSIONS

The clinical characteristics of the adult HSPN patients were correlated with the severity of the renal pathology. It is feasible to predict renal pathological changes according to the clinical manifestations of adult HSPN patients.

Prognostic Value of Renal Function for Cardiac Events in Patients Without Significant Stenosis on Coronary Computed Tomography Angiography

This study was conducted to determine clinical parameters predicting future major adverse cardiovascular events (MACEs) in patients without significant stenosis on coronary computed tomographic angiography (CCTA). A total of 625 patients with suspected coronary artery disease (CAD) who underwent CCTA that revealed insignificant (< 50%) CAD was reviewed in three cardiac centers. The MACEs including cardiac death, non-fatal myocardial infarction (MI), unstable angina and late (> 90 days after CCTA) revascularization were assessed. During the mean follow-up period of 819 ± 529 days (median 837 days), there were 28 cases of MACEs (4.5%). In multivariable Cox regression analysis, independent predictors for MACEs were male sex (hazard ratio [HR], 2.40; 95% confidence interval [CI], 1.01-5.69; P = 0.046) and low estimated creatinine clearance (eCCr) (< 60 mL/min/1.73 m(2)) (HR, 3.07; 95% CI, 1.22-7.74; P = 0.017). Low eCCr was the only independent predictor for hard events including cardiac death and MI (HR, 17.6, 95% CI, 1.44-215.7; P = 0.025). In conclusion, renal function is an independent predictor for cardiovascular events among patients without significant CAD by CCTA. Careful monitoring and preventive strategy are warranted in patients with impaired renal function even without significant CAD.

How to assess kidney function in outpatient clinics

BACKGROUND

In 2002, a new definition and classification of chronic kidney disease was published, and glomerular filtration rate < 60 ml/min/1.73 m(2) for 3 months or more was adapted to define chronic kidney disease irrespective of other signs of kidney damage.

AIMS

To discuss different ways to assess kidney function in outpatient clinics and especially in primary care.

METHODS

The PubMed database was searched for relevant articles.

RESULTS

The estimated glomerular filtration rate equations which take into account plasma creatinine, age, sex, race and body size have been developed to identify patients with chronic kidney disease formerly overlooked if the renal function had been assessed by plasma creatinine alone. Cystatin C-based equations have also been developed to enhance accuracy for individuals with whom creatinine-based estimates for kidney function are acknowledged to be less accurate.

DISCUSSION

The characteristics of the patients to whom the diagnostic test is applied can influence the sensitivity of the test. Thus, there is nowadays controversy over the best method to assess kidney function in general population.

CONCLUSION

In the overwhelming majority of patients currently treated in primary care, the CKD-EPI creatinine equation is suitable for estimating renal function. The CKD-EPIcr-cys equation would provide further reliability in individuals with a CKD-EPI creatinine eGFR of 45-59 ml/min/1.73 m(2) , but the cost of serum cystatin C analysis limits its use in everyday general practice.

Potentially modifiable risk factors for acute kidney injury after surgery on the thoracic aorta: a propensity score matched case-control study

Perioperative risk factors were identified for acute kidney injury (AKI) defined by the RIFLE criteria (RIFLE = risk, injury, failure, loss, end stage) after surgery on the thoracic aorta with cardiopulmonary bypass (CPB) in this case-control study. A retrospective review was completed for 702 patients who underwent surgery on the thoracic aorta with CPB. A total of 183 patients with AKI were matched 1:1 with patients without AKI by a propensity score. Matched variables included age, gender, body-mass index, preoperative creatinine levels, estimated glomerular filtration rate, a history of hypertension, diabetes mellitus, cerebrovascular accident, smoking history, or chronic obstructive pulmonary disease to exclude the influence of patient demographics, preoperative medical status, and baseline renal function. Multivariate logistic regression analysis was used to evaluate for independent risk factors in the matched sample of 366 patients. The incidence of AKI was 28.6% and 5.9% of patients from the entire sample required renal replacement therapy. AKI was associated with a prolonged postoperative hospital stay and a higher one-month and one-year mortality both in the entire and matched sample set. Independent risk factors for AKI were a left ventricular ejection fraction <55%, preoperative hemoglobin level <10 g/dL, albumin <4.0 g/dL, diagnosis of dissection, operation time >7 hours, deep hypothermic circulatory arrest (DHCA) time >30 min, pRBC transfusion >1000 mL, and FFP transfusion >500 mL. Although the incidence of poor glucose control (blood glucose >180 mg/dL) was higher in patients with AKI in matched sample, it was not an independent risk factor.AKI was still associated with a poor clinical outcome in the matched sample. Potentially modifiable risk factors included preoperative anemia and hypoalbuminemia. Efforts to minimize operation time and DHCA time along with transfusion amount may protect patients undergoing aortic surgery against AKI.

A Two-stage Dynamic Model to Enable Updating of Clinical Risk Prediction from Longitudinal Health Record Data: Illustrated with Kidney Function

We demonstrate the use of electronic records and repeated measures of risk factors therein, to enable deeper understanding of the relationship between the full longitudinal trajectory of risk factors and outcomes. To illustrate, dynamic mixed effect modelling is used to summarise the level, trend and monitoring intensity of kidney function. The output from this model then forms covariates for a recurrent event Cox proportional hazards model for predicting adverse events (AE). Using data from Salford, UK, our multivariate model finds that steeper declines in kidney function raise the hazard of AE (HR: 1.13, 95% CI (1.05, 1.22)). There is a non-proportional relationship between the hazard of AE and the monitoring intensity of kidney function. Neither of these variables would be present in a classical risk prediction model.. This work illustrates the potential of using the full longitudinal profile of risk factors, rather than just their level. There is an opportunity for deep statistical learning leading to rich clinical insight using longitudinal signals in electronic data.

The relationship between estimated GFR based on the CKD-EPI formula and renal inulin clearance in potential kidney donors

It is not yet clear whether or not renal function in the living donor can be sufficiently assessed by estimated glomerular filtration rate (GFR) using creatinine-based equations. The present paper investigates the relationship between GFR values determined using renal inulin clearance (Cin) and those estimated using the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) formula. Our study was performed in 287 potential kidney donors with a mean age of 48 ± 10 years. Mean Cin was 1.47 ± 0.28 (1.10 - 2.50) mL/s/1.73 m2. Total bias when using the CKDEPI formula was -0.0183 mL/s/1.73 m2, precision 0.263 mL/s/1.73 m2, and accuracy 90.6% within ± 30% of Cin. The sensitivity of CKD-EPI to estimate a decrease in Cin below 1.33 mL/s/1.73 m2 was 50.5%, with an 85% specificity of detecting a value above the cutoff. Receiver-operating curve analysis for the above produced an area under the curve of 0.766 ± 0.0285 (CI 0.712 - 0.813). For donor screening purposes, CKD-EPI should be interpreted with great caution.

Shape-based motion correction in dynamic contrast-enhanced MRI for quantitative assessment of renal function

PURPOSE

To incorporate a newly developed shape-based motion estimation scheme into magnetic resonance urography (MRU) and verify its efficacy in facilitating quantitative functional analysis.

METHODS

The authors propose a motion compensation scheme in MRU that consists of three sequential modules: MRU image acquisition, motion compensation, and quantitative functional analysis. They designed two sets of complementary experiments to evaluate the performance of the proposed method. In the first experiment, dynamic contrast enhanced (DCE) MR images were acquired from three sedated subjects, from which clinically valid estimates were derived and served as the "ground truth." Physiologically sound motion was then simulated to synthesize image sequences influenced by respiratory motion. Quantitative assessment and comparison were performed on functional estimates of Patlak number, glomerular filtration rate, and Patlak differential renal function without and with motion compensation against the ground truth. In the second experiment, the authors acquired a temporal series of noncontrast MR images under free breathing from a healthy adult subject. The performance of the proposed method on compensating real motion was evaluated by comparing the standard deviation of the obtained temporal intensity curves before and after motion compensation.

RESULTS

On DCE-MR images with simulated motion, the generated relative enhancement curves exhibited large perturbations and the Patlak numbers of the left and right kidney were significantly underestimated up to 35% and 34%, respectively, compared with the ground truth. After motion compensation, the relative enhancement curves exhibited much less perturbations and Patlak estimation errors reduced within 3% and 4% for the left and right kidneys, respectively. On clinical free-breathing MR images, the temporal intensity curves exhibited significantly reduced variations after motion compensation, with standard deviation decreased from 30.3 and 38.2 to 8.3 and 11.7 within two manually selected regions of interest, respectively.

CONCLUSIONS

The developed motion compensation method has demonstrated its ability to facilitate quantitative MRU functional analysis, with improved accuracy of pharmacokinetic modeling and quantitative parameter estimations. Future work will consider performing more intensive clinical verifications with sophisticated pharmacokinetic models and generalizing the proposed method to other quantitative DCE analysis, such as on liver or prostate function.

Male sex and vascular risk factors affect cystatin C-derived renal function in older people without diabetes or overt vascular disease

Background/objectives: to explore the effect of ageing on renal function with cystatin C as the marker of glomerular filtration rate (GFR) in the general population without vascular disease or diabetes.

Design: a cross-sectional analysis of a healthy subset from the Good Aging in Skåne-cohort study representative of the Swedish general population.

Subjects: 1252 participants without vascular disease and diabetes (43.9% men) of whom 203 were over 80 years old were included from the original cohort of 2931.

Methods: plasma cystatin C and plasma creatinine were used as markers for GFR. Estimated GFR (eGFR) was calculated with three chronic kidney disease epidemiology collaboration (CKD-EPI) formulas involving cystatin C, creatinine or both.

Results: the median for plasma cystatin C was 0.93 mg/l (60–69 years old), 1.04 (70–79 years old) and 1.24 (80+ years old). The difference in mg/l between the 5th and 95th percentile was 0.46, 0.62 and 0.90 for these age groups. Male sex increased the age effect on plasma cystatin C levels with 0.004 mg/l/year (P = 0.03), adjusted for vascular risk factors. Smoking, lower HDL and higher diastolic blood pressure were associated with higher cystatin C levels. 54.7% (CKD-EPI creatinine) to 73.9% (CKD-EPI cystatin C) of the 80+ had an eGFR < 60 ml/min/1.73 m².

Conclusion: non-diabetics without overt vascular disease exhibit an age related but heterogeneous decline in renal function. The ageing effect is more pronounced in men. At least half of healthy 80+ years old could be expected to have at least CKD Stage 3 with eGFR < 60 ml/min/1.73 m².

[Follow-up of analytical parameters in Internal Medicine patients to detect adverse events]

OBJECTIVE

To analyze the prevalence of prescription drugs, previously selected, that should be monitored by their analytical test, and the rate of alteration in these tests, with the aim of establishing priorities to facilitate monitoring.

METHOD

Prospective observational study in the Internal Medicine department of a referral hospital of 350 beds. In a first phase, we selected some drugs which analytical monitoring is recommended for the medical literature, and after that, we reviewed the pharmacological treatment of all patients admitted with any of these drugs. The study was conducted in the last two month of 2011.

RESULTS

We included 271 patients, 128 (47%) were women. The mean age was 74.5 ± 14.4 years and the average stay of 7 ± 5.8 days. These patients accounted for 83% of all patients admitted to Internal Medicine during the study period. There were 828 drugs that must be monitored; each patient had an average of 3.1 ± 2.3. We reviewed 1837 analytical test, of which 401 (22%) were altered and 154 patients (57%) were affected for it. The pairs drug-analytical test altered most frequently found were creatinine increased and nephrotoxic drugs, hypokalemia in patients taking high efficiency diuretics and thrombocytopenia in patients treated with low molecular weight heparins.

CONCLUSIONS

Our study highlights the importance of monitoring laboratory test associated with some drugs from the pharmacy department, as it demonstrates a high incidence of warning results. Our proposal for selection of drugs makes monitoring easier, and reaches large numbers of patients.

[Clinical course and outcomes of myocardial infarction in women]

We selected all case histories of patients living in the area served by the Syktyvkar policlinic #3 and treated in Republican Cardiological Dispensary in 2003-2009 with diagnosis of myocardial infarction (MI). Data on survival of patients after MI (mean duration of follow-up 4.6 years) was derived from information on date and cause of death of patients obtained from statistical office of the policlinic. Overall we analyzed data on 778 patients (46.3% women, mean age 63.7 years). For detection of independent factors related to lethal outcome we used binary logistic regression, for assessment of survival we used Kaplan-Meier method and Cox regression model of proportional hazards. From positions of gender differences we assessed pharmacoepidemiology of MI, efficacy of thrombolytic therapy, determined factors of hospital and long term mortality. No increase of risk of hospital or long term mortality associated with female sex was revealed by multifactorial analysis. Greatest prognostic significance in relation to unfavorable outcome irrespective of patients sex was established for the following factors: age, severity of MI course, severity of renal dysfunction. In acute period of MI in addition to these factors we revealed unfavorable influence of hyperglycemia and protective role of preceding hypertensive disease.