Optimal Oral Iron Therapy for Iron Deficiency Anemia Among US Veterans.

Importance: Optimal oral iron supplementation strategy is unclear in patients with iron deficiency anemia (IDA) who have either normal kidney function (NKF) or chronic kidney disease (CKD). Objective: To investigate the association of different oral iron supplementation strategies with the change in hemoglobin and iron indices among patients with IDA with either NKF or CKD. Design, Setting, and Participants: This retrospective cohort study was conducted between 2009 and 2019 at nationwide Veterans Health Administration facilities. Eligible participants included veterans with IDA (defined as hemoglobin <12 g/dL and either iron saturation <20% or ferritin <50 ng/mL) who received their first outpatient prescription of oral iron. Patients were further divided into those with NKF (estimated glomerular filtration rate >60 mL/min/1.73 m2) and CKD (estimated glomerular filtration rate ≥15 mL/min/1.73 m2 and <60 mL/min/1.73 m2). Data analysis was conducted from February to October 2023. Exposures: Patients were classified into 3 groups based on their oral iron dosing schedule: daily (once a day), multiple doses per day (MDD; ≥2 times per day), or alternate-day dose (ADD). Main Outcomes and Measures: The primary outcomes were change of hemoglobin, ferritin, total iron binding capacity (TIBC), and iron saturation (ISAT), which were calculated with linear mixed-effects models. Results: A total of 71 677 veterans with IDA (63 202 male [88.2%] and 8475 female [11.8%]; mean [SD] age, 68.47 [13.09] years), including 47 201 with NKF and 24 476 with CKD, were identifed. In patients with NKF in the daily group, hemoglobin increased from baseline (estimated per-30-day difference [SE], 0.27 [0.00] g/dL; P < .001). In comparison with the daily group, hemoglobin increased more in the MDD group (estimated per-30-day difference [SE], 0.08 [0.03] g/dL; P < .001), but no difference was noted in the ADD group (estimated per-30-day difference [SE], -0.01 [0.01] g/dL; P = .38). Ferritin, ISAT, and TIBC results were similar, except TIBC showed less change in the ADD group compared with the daily group. Patients with CKD showed similar trends but smaller magnitudes in changes. Among patients with NKF, the adjusted mean increase in hemoglobin was 1.03 g/dL (95% CI, 1.01-1.06 g/dL) for those in the daily group, 1.38 g/dL (95% CI, 1.36-1.40 g/dL) for those in the MDD group, and 0.93 g/dL (95% CI, 0.84-1.02 g/dL) for those in the ADD group at 90 days. Among patients with CKD, the adjusted mean increase in hemoglobin was 0.71 g/dL (95% CI, 0.68-0.73 g/dL) for those in the daily group, 0.99 g/dL (95% CI, 0.97-1.01 g/dL) for those in the MDD group, and 0.62 g/dL (95% CI, 0.52-0.73 g/dL) for those in the ADD group at 90 days. Conclusions and Relevance: In this retrospective cohort study of veterans with IDA, there was no significant difference in the improvement of hemoglobin and iron indices between daily and ADD groups, but quickest improvement was observed in the MDD group. These findings suggest that the choice of oral iron therapy should depend on the rapidity of response desired and patient preference due to adverse effects.

Acute Kidney Injury in Patients Undergoing Both Right and Left Heart Catheterization with Coronary Angiography Vs Right Heart Catheterization Only.

BACKGROUND: Recent studies have challenged the reported causal association between acute kidney injury and iodinated contrast administration, ascribing some cases to changes in renal function that are independent of contrast administration. METHODS: We studied 1779 consecutive patients undergoing right heart catheterization (RHC) at a Veterans Administration Medical Center. We compared the incidence of acute kidney injury and of nephropathy at 3 months in veterans undergoing right and left heart catheterization and coronary angiography (R&LHC) to the incidence of acute kidney injury and of nephropathy at 3 months in patients undergoing RHC only. RESULTS: The incidence of acute kidney injury at 3 days was 47 (9.7%) in the R&LHC group and 58 (9.6%) in the RHC group (P = .99). The incidence of nephropathy at 3 months was 115 (17%) in the L&RHC group and 141 (19.2%) in the RHC group (P = 0.31). In a propensity score-paired analysis of 782 patients and after adjustment for baseline characteristics, the odds ratio for acute kidney injury at 3 days among patients undergoing R&LHC was 1.25 (95% confidence interval, 0.65-2.42; P = .50), and the odds ratio for nephropathy at 3 months was 0.69 (95% confidence interval, 0.46-1.04; P = .08). CONCLUSION: The incidence of changes in creatinine consistent with acute kidney injury at 3 days and of nephropathy at 3 months was not significantly different in patients undergoing R&LHC compared with patients undergoing RHC only. This supports the thesis that not all changes in creatinine after procedures involving administration of contrast are caused by the contrast.

Improving the residual risk of renal and cardiovascular outcomes in diabetic kidney disease: A review of pathophysiology, mechanisms, and evidence from recent trials.

Based on global estimates, almost 10% of adults have diabetes, of whom 40% are estimated to also have chronic kidney disease (CKD). Almost 2 decades ago, treatments targeting the renin-angiotensin system (RAS) were shown to slow the progression of kidney disease. More recently, studies have reported the additive benefits of antihyperglycaemic sodium-glucose co-transporter-2 inhibitors in combination with RAS inhibitors on both CKD progression and cardiovascular outcomes. However, these recent data also showed that patients continue to progress to kidney failure or die from kidney- or cardiovascular-related causes. Therefore, new agents are needed to address this continuing risk. Overactivation of the mineralocorticoid (MR) receptor contributes to kidney inflammation and fibrosis, suggesting that it is an appropriate treatment target in patients with diabetes and CKD. Novel, selective non-steroidal MR antagonists are being studied in these patients, and the results of two large recently completed clinical trials have shown that one such treatment, finerenone, significantly reduces CKD progression and cardiovascular events compared with standard of care. This review summarizes the pathogenic mechanisms of CKD in type 2 diabetes and examines the potential benefit of novel disease-modifying agents that target inflammatory and fibrotic factors in these patients.

The conundrum of contrast-induced acute kidney injury.

More than sixty years have elapsed since contrast induced nephropathy (CIN) was first described in the medical literature. This term has since been extensively explored, with a variety of studies conducted to investigate its incidence and various mechanisms examined to explain its pathophysiology. However, the topic of CIN remains one of controversy with a widely variable and often questionable incidence derived from various studies. The past two decades have seen a surge in reports questioning the existing of CIN altogether and if more harm is actually being caused to patients out of fear of this potential complication. We have attempted to review relevant studies regarding CIN and highlight the key points of its surmised understanding. The review has a higher focus on more recent literature and updates, in order to determine if an accurate estimate can be made on the incidence of CIN. While there was certainly no lack of material available, practically all the studies reviewed were limited by one or more significant drawbacks that limited the reliability of their conclusions regarding CIN. Based on the information reviewed, the strengths and the flaws encountered in other studies can be used to design a randomized control trial that may help in concluding the longstanding debate on this topic. However due to time, financial, and perhaps even ethical constraints such a trial will be difficult to arrange, and so a definitive answer on CI-AKI, and whether it really exist, may continue to elude clinicians.

Can billing codes accurately identify rapidly progressing stage 3 and stage 4 chronic kidney disease patients: a diagnostic test study.

BACKGROUND: The International Classification of Diseases (ICD) coding system is the industry standard tool for billing, disease classification, and epidemiology purposes. However, ICD codes are often not assigned or incorrectly given, particularly among Chronic Kidney disease (CKD) patients. Our study evaluated the diagnostic accuracy of CKD-staging ICD codes among CKD patients from a large insurer database in identifying individuals rapidly progressing towards end-stage renal disease (ESRD). PATIENTS AND METHODS: Serial observations including outpatient serum creatinine measurements collected from 2007 through 2014 of 216,529 patients were examined. The progression of CKD using a serum creatinine based longitudinal mixed-model was contrasted with that documented by CKD-staging ICD codes. Rapid progressors, defined as those with yearly estimated glomerular filtration rate (eGFR) loss greater than 4 ml/min/1.73m2) were identified. The diagnosis of CKD using eGFR was also compared to diagnosis using a set of CKD related ICD codes. RESULTS: Of 10,927 clinically identified CKD patients qualifying for inclusion in the progression analysis, 323 were clinically identified as rapid progressors. CKD-staging ICD codes identified 83 of these, for a sensitivity of 25.7% with positive predictive value (PPV) of 13.74%, and specificity 95.09% with negative predictive value (NPV) of 97.68%. Of 28,762 laboratory-confirmed CKD patients, 9249 had a qualifying ICD code, for a sensitivity of 16% with PPV of 63.10%; Of 187,767 patients with laboratory-confirmed absence of CKD, 182,359 also did not have a qualifying ICD code, for a specificity of 97.12% with NPV of 90.33%. CONCLUSION: This study depicts the novel finding that ICD-codes display poor capacity to identify rapidly progressing CKD patients when compared to gold standard eGFR measures, and further demonstrates the limitations of coding in CKD diagnosis. This analysis further defines the limitations of ICD codes in addressing diagnosis of disease severity or disease progression for clinical or epidemiological purposes.

Acute kidney injury after non-cardiovascular surgery: risk factors and impact on development of chronic kidney disease and long-term mortality.

OBJECTIVE: To identify factors associated with acute kidney injury (AKI) and its progression to chronic kidney disease (CKD) in a non-cardiac/non-vascular surgery setting. METHODS: This study examined the Veterans Affairs Surgical Quality database for surgical entries between 2000-2014. Demographics, comorbidities, laboratory findings and hospital outcomes were assessed. The primary end-point was the occurrence of AKI, defined as an increase of ≥0.3 mg/dL, 48 h post-operatively. Major adverse cardiac event (MACE) was defined as the composite first occurrence of myocardial infarction, cardiac arrest, and death in 30 days (secondary end-point) and was compared between two groups. Rates of progression to CKD in 1 year and long-term survival were examined. MAIN OUTCOME MEASURES: Occurrence of AKI 48 h post-operatively. RESULTS: AKI was documented in 8.5% of patients. Age, diabetes, and chronic obstructive pulmonary disease, chronic kidney disease, platelet count, serum albumin level, and duration of surgery were identified as independent predictors of AKI. In total, 6.4% patients developed MACE, which was more frequent in patients with AKI (p < .001). Age and pre-operative hematocrit <30% were independent predictors of progression to CKD. Pre-operative hematocrit with a cut-off value of 30% was the only modifiable factor to predict the long-term survival. CONCLUSION: Development of AKI is associated with increased odds of various post-operative complications and long-term renal insufficiency and mortality.

Urinary versus plasma neutrophil gelatinase-associated lipocalin (NGAL) as a predictor of mortality for acute kidney injury in intensive care unit patients.

OBJECTIVE: To examine urinary and plasma neutrophil gelatinase-associated lipocalin (NGAL) levels in predicting ICU mortality. DESIGN: Prospective observational. SETTING: University Critical Care setting. PARTICIPANTS: 50 patients with acute kidney injury (AKI). INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Serial urinary and plasma concentrations of NGAL were measured. Twenty-five patients had early progression (EP) and 25 patients had early improvement (EI) of AKI. Plasma concentrations of NGAL in the EP group (N=25) were significantly higher than those in the EI group (129 [IQR; 20] vs. 111 [IQR; 32] ng/mL; P=0.009), while urine NGAL levels on admission were similar in both groups (61 [IQR; 20] vs. 65 [IQR; 20] ng/mL; P=0.767). Plasma NGAL concentrations rapidly decreased to 87 [32] ng/mL in the EI group (P<0.001) and while it remained elevated in the EP group (138 [21] ng/mL). Within 28-days, 50% of the patients died in the EP group, whereas no patient died in the EI group (P<0.001). Plasma NGAL was a fair predictor for progression of AKI (AUC; 0.719±0.063; P=0.006). 48-hour changes in plasma NGAL levels predicted death within 28-days of ICU admission (AUC; 0.874±0.048; P<0.001). CONCLUSION: Early progression of AKI was associated with more death within 28 and 90days. While one time measurement of plasma NGAL levels at the time ICU admission may represent the kidney health status in critical care settings, it does not reliably predict mortality. On the other hand, changes in plasma NGAL within 48h of admission improve the value of this biomarker in predicting ICU mortality.

Progression of kidney disease in elderly stage 3 and 4 chronic kidney disease patients.

PURPOSE: The prevalence of chronic kidney disease (CKD) has been rising steadily in the elderly population. We studied the rate of progression of CKD in this population and the factors associated with progression of CKD to better identify patients who are likely to progress to ESRD. METHODS: This was an observational study including 4562 patients older than 65 years with two outpatient estimated glomerular filtration rates (eGFRs) of <60 ml/min/1.73 m2, at least 90 days apart with no intervening eGFR >60 ml/min/1.73 m2 (March 1, 2001, and March 31, 2008) at VA healthcare facilities. Patients with eGFR <15 ml/min/1.73 m2 were excluded. Annual rate of decline of eGFR was studied and categorized as <1 ml/min/1.73 m2, 1-4 ml/min/1.73 m2, and >4 ml/min/1.73 m2. RESULTS: Mean age of the study participants was 77.2 years. 24.3% were diabetics. 4.3% had proteinuria. In univariate comparison of different rates of progression, 54.2% patients had an annual rate of progression of <1 ml/min/1.73 m2. Multivariable mixed model analyses revealed that increasing age, body mass index, presence of cardiovascular disease, diabetes mellitus, and proteinuria were associated with significantly increased rate of progression of CKD. Serum albumin and hemoglobin level were inversely associated with progression of CKD. CONCLUSIONS: CKD progresses at a slower rate in the elderly population. We have identified risk factors associated with an increased risk of progression of CKD in the elderly. This may help to improve health care planning and resource utilization.

Race and contrast-induced nephropathy in patients undergoing coronary angiography and cardiac catheterization.

Contrast-induced nephropathy (CIN) is an acute worsening of renal function after receiving intravascular contrast during a procedure. Some of the predisposing factors include underlying diabetes, chronic kidney disease, congestive heart failure, periprocedural hypotension, anemia, contrast volume, and osmolality of contrast; however, it remains unclear if risk varies for CIN with race and ethnicity. There is evidence in the literature showing the link between race/ethnicity and the discrepancies in the utilization of preventive care services and the resources related to cardiovascular and renal health. While these disparities continue to exist and affect some of the predictors of CIN, this review will explore the extent to which race and ethnicity directly affect CIN.

Preoperative serum potassium predicts the clinical outcome after non-cardiac surgery.

BACKGROUND: Potassium disorders have been linked to adverse outcomes in various medical conditions. However, the association of preoperative serum potassium with postoperative outcome is not well established. We aimed to examine the association between preoperative potassium with a 30-day mortality and adverse cardiovascular event (MACE). METHODS: We conducted a cohort study using a prospectively collected database of patients, undergoing surgical procedures from 1998 to 2013 in the VA Western New York Healthcare System, which are reported to the Veterans Affairs Surgical Quality Improvement Program (VASQIP). The patients were categorized into three groups based on their documented preoperative potassium concentrations. Hypokalemia was defined as serum potassium concentration <4 mmol/L and hyperkalemia was defined as serum potassium concentrations >5.5 mmol/L. The values within the range of 4.0-5.5 mmol/L were considered as normokalemia and used as the control group. Statistical analyses included Chi-square test, analysis of variance and multivariate logistic regression to estimate the risk of MACE within 30 days of surgery. RESULTS: Study included 5959 veterans who underwent surgery between 1998 and 2013. The patients in the hyperkalemics group had lower kidney function compared to the other two groups. The frequency of MACE was 13.6% in hypokalemics and 21.9% in hyperkalemics that were both significantly higher than 4.9% in controls. In multivariate logistic regression the hazard risk (HR) ratios of MACE were (2.17, 95% CI 1.75-2.70) for hypokalemics and (3.23, 95% CI 2.10-4.95) for hyperkalemics when compared to normokalemic controls. CONCLUSIONS: Preoperative hypokalemia and hyperkalemia are both independent predictors of MACE within 30 days.

Prevalence of chronic kidney disease in patients with chronic obstructive pulmonary disease: a systematic review and meta-analysis.

BACKGROUND: The incidence and prevalence of chronic kidney disease (CKD) continue to rise worldwide. Increasing age, diabetes, hypertension, and cigarette smoking are well-recognized risk factors for CKD. Chronic obstructive pulmonary disease (COPD) is characterized by chronic airway inflammation leading to airway obstruction and parenchymal lung destruction. Due to some of the common pathogenic mechanisms, COPD has been associated with increased prevalence of CKD. METHODS: Systematic review of medical literature reporting the incidence and prevalence of CKD in patients with COPD using the Cochrane Collaboration Methodology, and conduct meta-analysis to study the cumulative effect of the eligible studies. We searched Medline via Ovid, PubMed, EMBASE and ISI Web of Science databases from 1950 through May, 2016. We included prospective and retrospective observational studies that reported the prevalence of CKD in patients with COPD. RESULTS: Our search resulted in 19 eligible studies of which 9 have been included in the meta-analysis. The definition of CKD was uniform across all the studies included in analysis. COPD was found to be associated with CKD in the included epidemiological studies conducted in many countries. Our meta-analysis showed that COPD was found to be associated with a significantly increased prevalence of CKD (Odds Ratio [OR] = 2.20; 95% Confidence Interval [CI] 1.83, 2.65). STUDY LIMITATIONS: Studies included are observational studies. However, given the nature of our research question there is no possibility to perform a randomized control trial. CONCLUSIONS: Patients with COPD have increased odds of developing CKD. Future research should investigate the pathophysiological mechanism behind this association, which may lead to better outcomes.

Proton pump inhibitors are associated with increased risk of development of chronic kidney disease.

BACKGROUND: Acute interstitial nephritis secondary to proton pump inhibitors (PPIs) frequently goes undiagnosed due to its subacute clinical presentation, which may later present as chronic kidney disease (CKD). We investigated the association of PPI use with the development of CKD and death. METHODS: Two separate retrospective case-control study designs were employed with a prospective logistic regression analysis of data to evaluate the association of development of CKD and death with PPI use. The population included 99,269 patients who were seen in primary care VISN2 clinics from 4/2001 until 4/2008. For evaluation of the CKD outcome, 22,807 with preexisting CKD at the first observation in Veterans Affairs Health Care Upstate New York (VISN2) network data system were excluded. Data obtained included use of PPI (Yes/No), demographics, laboratory data, pre-PPI comorbidity variables. RESULTS: A total of 19,311/76,462 patients developed CKD. Of those who developed CKD 24.4 % were on PPI. Patients receiving PPI were less likely to have vascular disease, COPD, cancer and diabetes. Of the total of 99,269 patients analyzed for mortality outcome, 11,758 died. A prospective logistic analysis of case-control data showed higher odds for development of CKD (OR 1.10 95 % CI 1.05-1.16) and mortality (OR 1.76, 95 % CI 1.67-1.84) among patients taking PPIs versus those not on PPIs. CONCLUSIONS: Use of proton pump inhibitors is associated with increased risk of development of CKD and death. With the large number of patients being treated with proton pump inhibitors, healthcare providers need to be better educated about the potential side effects of these medications.

Positive Predictive Value of a Single Assessment of Estimated GFR in the Diagnosis of Chronic Kidney Disease.

OBJECTIVES: The positive predictive value (PPV) of a single assessment of estimated glomerular filtration rate (eGFR) in the diagnosis of chronic kidney disease (CKD) is not known. Our objective was to determine the PPV of a single assessment of eGFR among adults with at least one eGFR <60 mL/min in their lifetime, using the Distributed Area Research and Therapeutics Network CKD natural history dataset. METHODS: In all, 47,104 adults who were cared for by 113 practices in the United States were included. Proportions of patients in eGFR categories at baseline were calculated using the following categories: <15 mL/min, 15 to 29.99 mL/min, 30 to 44.99 mL/min, and 45 to 59.99 mL/min. Comparisons were then made between the baseline and the endpoint to identify patients who had a follow-up eGFR that remained at <60 mL/min. The proportions of patients in each eGFR category were compared baseline to endpoint using cross-tabulations. To test the proposed cutpoint, the proportions of patients who had an eGFR that remained at <60 mL/min were measured, using the cutpoints that included the highest cumulative proportion of patients. The sensitivity and specificity of that cutpoint were calculated. RESULTS: A cutpoint of <45 mL/min was identified, yielding a PPV of 93% with a sensitivity of 28% and a specificity of 94%. CONCLUSIONS: A valid cutpoint to screen for CKD was identified. This cutpoint may prove important to early screening for CKD while reducing the burden on the healthcare system and patients suspected of having CKD.

Prevalence of various comorbidities among veterans with chronic kidney disease and its comparison with other datasets.

Chronic kidney disease (CKD) has a complicated interrelationship with various comorbidities. The purpose of this study was to describe the prevalence of various comorbidities among veterans with CKD and compare it with other datasets like Kidney Early Evaluation Program (KEEP), National Health and Nutrition Examination Survey (NHANES) and Medicare. Patients who had at least one outpatient visit in year 2007 (1 January 2007 to 31 December 2007) were included in the study (n = 75,787). Glomerular filtration rate (eGFR) was estimated by the Modification of Diet in Renal Disease (MDRD) study equation. CKD prevalence was calculated based on one or two serum creatinine values at least 3 months apart. Demographic data were obtained including age, gender, race, weight, height and body mass index (BMI). The prevalence of various comorbidities was also collected based on ICD 9 codes from the problem list. The prevalence of CKD among veterans was 47.3%, much higher than estimated in the US population. Patients with CKD were more likely to have any vascular disease (36.89% vs. 14.87%), diabetes (34.18% vs. 17.83%), hypertension (86.65% vs. 57.56%), and cancer (18.69% vs. 9.23%). Irrespective of age, the prevalence of vascular disease was much higher among veterans with CKD. The prevalence of coronary artery disease, peripheral vascular disease, and cancer was much higher among elderly veterans with CKD as compared to other datasets. CKD is a growing endemic associated with a high frequency of concomitant chronic illnesses. Public health resources should be applied for early recognition and risk modification of CKD.

Renin-Angiotensin-Aldosterone System Blockers in Elderly Adults with Chronic Kidney Disease without Diabetes Mellitus or Proteinuria.

OBJECTIVES: To compare the effect of renin-angiotensin-aldosterone system (RAAS) blockers with that of other antihypertensive agents on outcomes in a cohort of elderly veterans with incident chronic kidney disease (CKD) without diabetes mellitus or proteinuria. DESIGN: Retrospective cohort study. SETTING: Veterans Affairs (VA) Upstate New York Healthcare System. PARTICIPANTS: All participants were seen in primary care clinic in Veterans Integrated Service Network 2, which comprises five VA medical centers and 29 community-based outpatient clinics, from April 2001 to April 2008. Veterans with incident CKD who were taking antihypertensive medications and did not have proteinuria or diabetes mellitus on the date of onset of CKD were selected from this population. MEASUREMENTS: The outcome variables studied were progression of kidney disease (doubling of serum creatinine level or Stage 5 CKD (estimated glomerular filtration rate <15 mL/min per 1.73 m2 )), all-cause mortality, and combined outcome. RESULTS: Analysis included 2,474 participants, 47.9% of whom were taking RAAS blockers at baseline and the rest other antihypertensives. Time-varying Cox proportional hazards analyses did not reveal a statistically significant difference in primary combined outcome in participants taking RAAS blockers and those taking other antihypertensives (hazard ratio = 1.09, 95% confidence interval = 0.93-1.27). There was also no significant effect on individual outcomes (death or progression of kidney disease). CONCLUSION: Use of RAAS blockers was not associated with less hazard of combined and individual outcomes (doubling of serum creatinine, Stage 5 CKD, death) in elderly veterans with incident CKD without diabetes mellitus or proteinuria.

An observational study of the quality of care for chronic kidney disease: a Buffalo and Albany, New York metropolitan area study.

BACKGROUND: The database of a major regional health insurer was employed to identify the number and frequency of covered patients with chronic kidney disease (CKD). We then examined the characteristics of their care as defined, in part, by the frequency of physician visits and specialty referral, the characteristics of laboratory testing and total costs as indices of the quality of care of the subject population. METHODS: This retrospective, cross-sectional study analyzed insurance claims, laboratory results and medication prescription data. Patients with two estimated glomerular filtration rate readings below 60 ml/min/1.73 m(2) (n = 20,388) were identified and classified by CKD stage. RESULTS: The prevalence of CKD stages 3a and above was 12 %. Vascular comorbidities were common with prevalence increasing steadily from stage 3a through stage 5. Only 55.6 % of stage 4 CKD patients had claims for nephrology visits within one year of their index date. Fifty-nine percent of patients had claims for renin-angiotensin system (RAS) blockers. Twenty-five percent of patients in stage 3a CKD filled a prescription for non-steroidal anti-inflammatory drugs. Fifty-two percent of patients who developed end-stage renal disease received their first dialysis treatment as inpatients. CONCLUSIONS: The pattern of medical practice observed highlights apparent deficiencies in the care of CKD patients including inappropriate medication use, delayed nephrology referral, and a lack of preparation for dialysis. This study shows the potential value of using large patient databases available through insurers to assess and likely improve regional CKD care.

Intraoperative administration of vasopressin during coronary artery bypass surgery is associated with acute postoperative kidney injury.

BACKGROUND: Severe vasodilatation is commonly seen upon weaning from cardiopulmonary bypass (CPB). We examined the effects of vasopressin (arginine vasopressin [AVP]) on acute kidney injury (AKI) in postoperative period. METHODS: The records of 483 patients undergoing coronary bypass surgery on CPB from 2004 to 2008 were retrospectively reviewed. Demographic, anthropometric, comorbid condition, and perioperative clinical/laboratory data were collected along with postoperative complications. Patients were grouped based on the perioperative use of AVP, and AKI was used as the primary end point. Univariate and multivariate logistic regression analyses were used, followed by propensity score matching for AKI. Null hypothesis was rejected at P < .05. RESULTS: Postoperative AKI occurred in 14.5% of patients. Arginine vasopressin was administered to 280 patients during the perioperative period. The prevalence of AKI in AVP was 20%, whereas it was 6.1% in controls (P < .0001). Arginine vasopressin was an independent factor that predicted the occurrence of AKI (odds ratio, 3.60; 95% confidence interval, 1.22-10.62; P = .02). However, after propensity score matching, the association between AKI and AVP was lost (P = .073). CONCLUSION: Acute kidney injury is a common complication after cardiac surgery, and vasopressin use increases its incidence; however, this effect may rely on several clinical factors, and its true effect should be examined by large randomized trials.

The effect of adding functional classification to ASA status for predicting 30-day mortality.

BACKGROUND: The functional capacity to perform the activities of daily living is identified as an independent predictor of perioperative mortality but is not formally incorporated in the American Society of Anesthesiologists (ASA) classification. Our primary objective was to assess whether functional capacity is an independent predictor of 30-day and long-term mortality in a general population and, if so, to define how it may formally be incorporated into the routine preoperative ASA classification assessment. METHODS: This retrospective, observational cohort study was conducted using 1998 to 2009 data extracted from the Veterans Affairs Surgical Quality Improvement Program of Western New York, a perioperative prospectively maintained database. Mortality follow-up was performed for all records in 2013. This population-based sample included all patients undergoing any noncardiac surgery (n = 12,324). Each patient's ASA class (assigned preoperatively) was appended with subclasses A or B, with A representing patients who were functionally independent and B representing partially or fully dependent patients. The primary outcome was all-cause mortality during the follow-up period. Secondary outcomes included 30-day postoperative complications and mortality. Multivariate logistic regression was used to identify independent risk factors for mortality. RESULTS: The likelihood for mortality was significantly lower for A patients than B patients within each ASA class. The odds ratios for mortality for group A patients significantly favored survival over group B within each ASA class (0.14, 0.29, and 0.50, for ASA class II, III, and IV, respectively, each P < 0.0001). The odds ratio for mortality of IIB over IIIA patients was 1.92 (95% confidence interval [CI], 1.19-3.11; P = 0.01); 1.29 (95% CI, 1.04-1.60; P = 0.03) for IIIB over IVA patients; and 2.03 (95% CI, 0.99-4.12, P=0.11) for IVB over ASA V patients, despite each higher class carrying a greater disease burden, by definition. The area under the curve the receiver operator characteristic curve was 0.811 ± 0.010 for traditional ASA classification in predicting death within 30 days, which improved 4.7% to 0.848 ± 0.008 using the modified ASA classification, P < 0.00001. CONCLUSIONS: Functional capacity was an independent predictor of mortality within each ASA class, indicating that it should be considered for incorporation into the routine preoperative evaluation. Functional dependence may be an indication for increasing a patient's ASA class by 1 class-point to better reflect his or her perioperative risk, but prospective validation of these findings is recommended, as this is a preliminary study.