Preoperative proteinuria is independently associated with mortality after fenestrated endovascular aneurysm repair.

OBJECTIVE: Fenestrated endovascular aneurysm repair (FEVAR) has become a mainstay in treating complex aortic aneurysms, though baseline patient factors predicting long-term outcomes remain poorly understood. Proteinuria is an early marker for chronic kidney disease and associated with adverse cardiovascular outcomes, but its utility in patients with aortic aneurysms is unknown. We aimed to determine whether preoperative proteinuria impacts long-term survival after FEVAR. METHODS: A single-institution, retrospective review of all elective FEVAR was performed. Preoperative proteinuria was assessed by urinalysis: negative (0-29 mg/dL), 1+ (30-100 mg/dL), 2+ (101-299 mg/dL), and 3+ (≥300 mg/dL). The cohort was stratified by patients with proteinuria (≥30 mg/dL) vs those without (<30 mg/dL). Baseline, perioperative, and long-term outcomes were compared. The primary outcome, all-cause mortality, was evaluated by Kaplan-Meier analysis and independent predictors with Cox proportional hazards modeling. RESULTS: Among 181 patients who underwent standard FEVAR from 2012 to 2022 (mean follow-up 33 months), any proteinuria was noted in 30 patients (16.6%). Patients with proteinuria were more likely to be Black (10.0% vs 1.3%) with a lower estimated glomerular filtration rate (eGFR) (52.7 ± 24.7 vs 67.7 ± 20.5 mL/min/1.73 m2), higher Society for Vascular Surgery comorbidity score (10.9 ± 4.3 vs 8.2 ± 4.7) and calcium channel blocker therapy (50.0% vs 29.1%), and larger maximal aneurysm diameter (67.2 ± 16.9 vs 59.8 ± 9.8 mm) (all P < .05). Thirty-day mortality was higher in the proteinuria group (10.0% vs 1.3%; P = .03). Overall survival at 1 and 5 years was significantly lower for those with proteinuria (71.5% vs 92.3% and 29.5% vs 68.1%; log-rank P < .001). On multivariable analysis, preoperative proteinuria was independently associated with over threefold higher hazard of mortality (hazard ratio [HR]: 3.21, 95% confidence interval [CI]: 1.66-6.20; P < .001), whereas preoperative eGFR was not predictive (HR: 0.99, 95% CI: 0.98-1.01; P = .28). Additional significant predictors included chronic obstructive pulmonary disease (HR: 2.04), older age (HR: 1.05), and larger maximal aneurysm diameter (HR: 1.03; all P < .05). CONCLUSIONS: In our 10-year experience with FEVAR, preoperative proteinuria was observed in 17% of patients and was significantly associated with worse survival. In this cohort, proteinuria was independently associated with all-cause mortality, whereas eGFR was not, suggesting that urinalysis may provide an additional simple metric for risk-stratifying patients before FEVAR.

Association Between Preoperative Hemodialysis Timing and Postoperative Mortality in Patients With End-stage Kidney Disease.

Importance: For patients with end-stage kidney disease treated with hemodialysis, the optimal timing of hemodialysis prior to elective surgical procedures is unknown. Objective: To assess whether a longer interval between hemodialysis and subsequent surgery is associated with higher postoperative mortality in patients with end-stage kidney disease treated with hemodialysis. Design, Setting, and Participants: Retrospective cohort study of 1 147 846 procedures among 346 828 Medicare beneficiaries with end-stage kidney disease treated with hemodialysis who underwent surgical procedures between January 1, 2011, and September 30, 2018. Follow-up ended on December 31, 2018. Exposures: One-, two-, or three-day intervals between the most recent hemodialysis treatment and the surgical procedure. Hemodialysis on the day of the surgical procedure vs no hemodialysis on the day of the surgical procedure. Main Outcomes and Measures: The primary outcome was 90-day postoperative mortality. The relationship between the dialysis-to-procedure interval and the primary outcome was modeled using a Cox proportional hazards model. Results: Of the 1 147 846 surgical procedures among 346 828 patients (median age, 65 years [IQR, 56-73 years]; 495 126 procedures [43.1%] in female patients), 750 163 (65.4%) were performed when the last hemodialysis session occurred 1 day prior to surgery, 285 939 (24.9%) when the last hemodialysis session occurred 2 days prior to surgery, and 111 744 (9.7%) when the last hemodialysis session occurred 3 days prior to surgery. Hemodialysis was also performed on the day of surgery for 193 277 procedures (16.8%). Ninety-day postoperative mortality occurred after 34 944 procedures (3.0%). Longer intervals between the last hemodialysis session and surgery were significantly associated with higher risk of 90-day mortality in a dose-dependent manner (2 days vs 1 day: absolute risk, 4.7% vs 4.2%, absolute risk difference, 0.6% [95% CI, 0.4% to 0.8%], adjusted hazard ratio [HR], 1.14 [95% CI, 1.10 to 1.18]; 3 days vs 1 day: absolute risk, 5.2% vs 4.2%, absolute risk difference, 1.0% [95% CI, 0.8% to 1.2%], adjusted HR, 1.25 [95% CI, 1.19 to 1.31]; and 3 days vs 2 days: absolute risk, 5.2% vs 4.7%, absolute risk difference, 0.4% [95% CI, 0.2% to 0.6%], adjusted HR, 1.09 [95% CI, 1.04 to 1.13]). Undergoing hemodialysis on the same day as surgery was associated with a significantly lower hazard of mortality vs no same-day hemodialysis (absolute risk, 4.0% for same-day hemodialysis vs 4.5% for no same-day hemodialysis; absolute risk difference, -0.5% [95% CI, -0.7% to -0.3%]; adjusted HR, 0.88 [95% CI, 0.84-0.91]). In the analyses that evaluated the interaction between the hemodialysis-to-procedure interval and same-day hemodialysis, undergoing hemodialysis on the day of the procedure significantly attenuated the risk associated with a longer hemodialysis-to-procedure interval (P<.001 for interaction). Conclusions and Relevance: Among Medicare beneficiaries with end-stage kidney disease, longer intervals between hemodialysis and surgery were significantly associated with higher risk of postoperative mortality, mainly among those who did not receive hemodialysis on the day of surgery. However, the magnitude of the absolute risk differences was small, and the findings are susceptible to residual confounding.

Comparison of Pre-Amputation Evaluation in Patients with and without Chronic Kidney Disease.

INTRODUCTION: Patients with chronic kidney disease (CKD) and peripheral artery disease (PAD) are more likely to undergo lower extremity amputation than patients with preserved kidney function. We sought to determine whether patients with CKD were less likely to receive pre-amputation care in the 1-year prior to lower extremity amputation compared to patients without CKD. METHODS: We conducted a retrospective observational study of patients with PAD-related lower extremity amputation between January 2014 and December 2017 using a large commercial insurance database. The primary exposure was CKD identified using billing codes and laboratory values. The primary outcomes were receipt of pre-amputation care, defined as diagnostic evaluation (ankle-brachial index, duplex ultrasound, and computed tomographic angiography), specialty care (vascular surgery, cardiology, orthopedic surgery, and podiatry), and lower extremity revascularization in the 1-year prior to amputation. We conducted separate logistic regression models to estimate the adjusted odds ratio (aOR) and 95% confidence intervals (CIs) among patients with and without CKD. We assessed for effect modification by age, sex, Black race, and diabetes status. RESULTS: We identified 8,554 patients with PAD-related amputation. In fully adjusted models, patients with CKD were more likely to receive diagnostic evaluation (aOR 1.30; 95% CI 1.17-1.44) and specialty care (aOR 1.45, 95% CI 1.27-1.64) in the 1-year prior to amputation. There was no difference in odds of revascularization by CKD status (aOR 1.03, 0.90-1.19). Age, sex, Black race, and diabetes status did not modify these associations. DISCUSSION/CONCLUSION: Patients with CKD had higher odds of receiving diagnostic testing and specialty care and similar odds of lower extremity revascularization in the 1-year prior to amputation than patients without CKD. Disparities in access to pre-amputation care do not appear to explain the higher amputation rates seen among patients with CKD.

Executive summary of the KDIGO 2021 Clinical Practice Guideline for the Management of Blood Pressure in Chronic Kidney Disease.

The Kidney Disease: Improving Global Outcomes (KDIGO) 2021 Clinical Practice Guideline for the Management of Blood Pressure in Chronic Kidney Disease for patients not receiving dialysis represents an update to the KDIGO 2012 guideline on this topic. Development of this guideline update followed a rigorous process of evidence review and appraisal. Guideline recommendations are based on systematic reviews of relevant studies and appraisal of the quality of the evidence. The strength of recommendations is based on the "Grading of Recommendations Assessment, Development and Evaluation" (GRADE) approach. The scope includes topics covered in the original guideline, such as optimal blood pressure targets, lifestyle interventions, antihypertensive medications, and specific management in kidney transplant recipients and children. Some aspects of general and cardiovascular health, such as lipid and smoking management, are excluded. This guideline also introduces a chapter dedicated to proper blood pressure measurement since all large randomized trials targeting blood pressure with pivotal outcomes used standardized preparation and measurement protocols adhered to by patients and clinicians. Based on previous and new evidence, in particular the Systolic Blood Pressure Intervention Trial (SPRINT) results, we propose a systolic blood pressure target of less than 120 mm Hg using standardized office reading for most people with chronic kidney disease (CKD) not receiving dialysis, the exception being children and kidney transplant recipients. The goal of this guideline is to provide clinicians and patients a useful resource with actionable recommendations supplemented with practice points. The burden of the recommendations on patients and resources, public policy implications, and limitations of the evidence are taken into consideration. Lastly, knowledge gaps and recommendations for future research are provided.

Central venous pressure and the risk of diuretic-associated acute kidney injury in patients after cardiac surgery.

BACKGROUND: When prescribing diuretics in the postcardiac surgical intensive care unit (ICU), clinicians may use central venous pressure (CVP) to assess volume status and the risk of acute kidney injury (AKI). In this study, we examined how the risk of diuretic-associated AKI varied with CVP in patients undergoing cardiac surgery. METHODS: We used the Medical Information Mart for Intensive Care database to study adults admitted to the postcardiac surgical ICU at an urban, academic medical center between 2001 and 2012. We examined the odds of AKI per 1-mm Hg increase in CVP among patients receiving intravenous loop diuretics using multivariable adjusted logistic regression. We examined the risk of AKI among patients with diuretic use (vs nonuse) across tertiles of CVP using inverse probability treatment weighting. RESULTS: Among 4,164 patients receiving intravenous loop diuretics, the adjusted odds of subsequent AKI were 1.11 (95% CI 1.08-1.13) times higher per mm Hg increase in mean CVP. This association was log-linear across the entire range of CVPs observed. In the analysis of diuretic use (n = 5,396), the adjusted risk ratio for AKI with diuretic use (vs nonuse) was 1.33 (95% CI 1.21-1.47) and did not materially differ across tertile of CVP. CONCLUSIONS: Higher rather than lower CVP is an independent marker of AKI risk. The risk of AKI associated with diuretic use may not be influenced by CVP. Novel methods of assessing volume status and AKI risk are needed to guide patient selection for diuretic therapy.

Outcomes after left ventricular assist device implantation in patients with acute kidney injury.

OBJECTIVE: The study objective was to compare outcomes for patients with and without acute kidney injury during hospitalizations when left ventricular assist devices are implanted. METHODS: By using the National Inpatient Sample from 2008 to 2013, we identified patients with an International Classification of Diseases, Ninth Revision procedure code for left ventricular assist device implantation (37.66). We ascertained the presence of acute kidney injury and acute kidney injury requiring dialysis using validated International Classification of Diseases, Ninth Revision codes. We used logistic regression to examine the association of nondialysis-requiring acute kidney injury and acute kidney injury requiring dialysis with mortality, procedural complications, and discharge destination. RESULTS: We identified 8362 patients who underwent left ventricular assist device implantation, of whom 3760 (45.0%) experienced nondialysis-requiring acute kidney injury and 426 (5.1%) experienced acute kidney injury requiring dialysis. In-hospital mortality was 3.9% for patients without acute kidney injury, 12.2% for patients with nondialysis-requiring acute kidney injury, and 47.4% for patients with acute kidney injury requiring dialysis. Patients with nondialysis-requiring acute kidney injury and acute kidney injury requiring dialysis had higher adjusted odds of mortality (3.24, 95% confidence interval [CI], 2.04-5.13 and 20.8, 95% CI, 9.7-44.2), major bleeding (1.38, 95% CI, 1.08-1.77 and 2.44, 95% CI, 1.47-4.04), sepsis (2.69, 95% CI, 1.93-3.75 and 5.75, 95% CI, 3.46-9.56), and discharge to a nursing facility (2.15, 95% CI, 1.51-3.07 and 5.89, 95% CI, 2.67-12.99). CONCLUSIONS: More than 1 in 10 patients with acute kidney injury and approximately 1 in 2 patients with acute kidney injury requiring dialysis died during their hospitalization, with only 30% of patients with acute kidney injury requiring dialysis discharged to home. This information is necessary to support shared decision-making for patients with advanced heart failure and acute kidney injury.

Patterns of diuretic use in the intensive care unit.

PURPOSE: To inform future outcomes research on diuretics, we sought to describe modern patterns of diuretic use in the intensive care unit (ICU), including diuretic type, combination, and dosing. We also investigated two possible quality improvement targets: furosemide dosing in renal impairment and inclusion of an initial bolus with continuous furosemide infusions. MATERIALS AND METHODS: In this descriptive study, we retrospectively studied 46,037 adult ICU admissions from a publicly available database of patients in an urban, academic medical center. RESULTS: Diuretics were employed in nearly half (49%, 22,569/46,037) of ICU admissions. Mechanical ventilation, a history of heart failure, and admission to the post-cardiac surgery unit were associated with a higher frequency of diuretic use. Combination use of different diuretic classes was uncommon. Patients with severely impaired kidney function were less likely to receive diuretics. Furosemide was by far the most common diuretic given and the initial intravenous dose was only 20 mg in more than half of ICU admissions. Among patients treated with a continuous infusion, 30% did not receive a bolus on the day of infusion initiation. CONCLUSIONS: Patterns of diuretic use varied by patient-specific factors and by ICU type. Diuretic dosing strategies may be suboptimal.

Risk Stratification and Treatment of Coronary Disease in Chronic Kidney Disease and End-Stage Kidney Disease.

Patients with advanced chronic kidney disease have an enormous burden of cardiovascular morbidity and mortality, but, paradoxically, their representation in randomized trials for the evaluation and management of coronary artery disease has been limited. Clinicians therefore are faced with the conundrum of synergizing evidence from observational studies, expert opinion, and extrapolation from the general population to provide care to this complex and clinically distinct patient population. In this review, we address clinical risk stratification of patients with chronic kidney disease and end-stage kidney disease using traditional cardiovascular risk factors, noninvasive functional and structural cardiac imaging, invasive coronary angiography, and cardiovascular biomarkers. We highlight the unique characteristics of this population, including the high competing risk of all-cause mortality relative to the risk of major adverse cardiac events, likely owing to important contributions from nonatherosclerotic mechanisms. We further discuss the management of coronary artery disease in patients with chronic kidney disease and end-stage kidney disease, including evidence pertaining to medical management, coronary revascularization with percutaneous coronary intervention, and coronary artery bypass grafting. Our discussion includes considerations of drug-eluting versus bare metal stents for percutaneous coronary intervention and off-pump versus on-pump coronary artery bypass graft surgery. Finally, we address currently ongoing randomized trials, from which clinicians are optimistic about receiving guidance regarding the best strategies to incorporate into their practice for the evaluation and management of coronary artery disease in this high-risk population.

Visit-to-Visit Office Blood Pressure Variability and Cardiovascular Outcomes in SPRINT (Systolic Blood Pressure Intervention Trial).

Studies of visit-to-visit office blood pressure (BP) variability (OBPV) as a predictor of cardiovascular events and death in high-risk patients treated to lower BP targets are lacking. We conducted a post hoc analysis of SPRINT (Systolic Blood Pressure Intervention Trial), a well-characterized cohort of participants randomized to intensive (<120 mm Hg) or standard (<140 mm Hg) systolic BP targets. We defined OBPV as the coefficient of variation of the systolic BP using measurements taken during the 3-,6-, 9-, and 12-month study visits. In our cohort of 7879 participants, older age, female sex, black race, current smoking, chronic kidney disease, and coronary disease were independent determinants of higher OBPV. Use of thiazide-type diuretics or dihydropyridine calcium channel blockers was associated with lower OBPV whereas angiotensin-converting enzyme inhibitors or angiotensin receptor blocker use was associated with higher OBPV. There was no difference in OBPV in participants randomized to standard or intensive treatment groups. We found that OBPV had no significant associations with the composite end point of fatal and nonfatal cardiovascular events (n=324 primary end points; adjusted hazard ratio, 1.20; 95% confidence interval, 0.85-1.69, highest versus lowest quintile) nor with heart failure or stroke. The highest quintile of OBPV (versus lowest) was associated with all-cause mortality (adjusted hazard ratio, 1.92; confidence interval, 1.22-3.03) although the association of OBPV overall with all-cause mortality was marginal (P=0.07). Our results suggest that clinicians should continue to focus on office BP control rather than on OBPV unless definitive benefits of reducing OBPV are shown in prospective trials. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT01206062.

Safety of Intravenous Iron in Hemodialysis: Longer-term Comparisons of Iron Sucrose Versus Sodium Ferric Gluconate Complex.

BACKGROUND: Controversy exists about any differences in longer-term safety across different intravenous iron formulations routinely used in hemodialysis (HD) patients. We exploited a natural experiment to compare outcomes of patients initiating HD therapy in facilities that predominantly (in ≥90% of their patients) used iron sucrose versus sodium ferric gluconate complex. STUDY DESIGN: Retrospective cohort study of incident HD patients. SETTING & PARTICIPANTS: Using the US Renal Data System, we hard-matched on geographic region and center characteristics HD facilities predominantly using ferric gluconate with similar ones using iron sucrose. Subsequently, incident HD patients were assigned to their facility iron formulation exposure. INTERVENTION: Facility-level use of iron sucrose versus ferric gluconate. OUTCOMES: Patients were followed up for mortality from any, cardiovascular, or infectious causes. Medicare-insured patients were followed up for infectious and cardiovascular (stroke or myocardial infarction) hospitalizations and for composite outcomes with the corresponding cause-specific deaths. MEASUREMENTS: HRs. RESULTS: We matched 2,015 iron sucrose facilities with 2,015 ferric gluconate facilities, in which 51,603 patients (iron sucrose, 24,911; ferric gluconate, 26,692) subsequently initiated HD therapy. All recorded patient characteristics were balanced between groups. Over 49,989 person-years, 10,381 deaths (3,908 cardiovascular and 1,209 infectious) occurred. Adjusted all-cause (HR, 0.98; 95% CI, 0.93-1.03), cardiovascular (HR, 0.96; 95% CI, 0.89-1.03), and infectious mortality (HR, 0.98; 95% CI, 0.86-1.13) did not differ between iron sucrose and ferric gluconate facilities. Among Medicare beneficiaries, no differences between ferric gluconate and iron sucrose facilities were observed in fatal or nonfatal cardiovascular events (HR, 1.01; 95% CI, 0.93-1.09). The composite infectious end point occurred less frequently in iron sucrose versus ferric gluconate facilities (HR, 0.92; 95% CI, 0.88-0.96). LIMITATIONS: Unobserved selection bias from nonrandom treatment assignment. CONCLUSIONS: Patients initiating HD therapy in facilities almost exclusively using iron sucrose versus ferric gluconate had similar longer-term outcomes. However, there was a small decrease in infectious hospitalizations and deaths in patients dialyzing in facilities predominantly using iron sucrose. This difference may be due to residual confounding, random chance, or a causal effect.

Orthostatic changes in systolic blood pressure among SPRINT participants at baseline.

Orthostatic changes in systolic blood pressure (SBP) impact cardiovascular outcomes. In this study, we aimed to determine the pattern of orthostatic systolic pressure changes in participants enrolled in the SBP Intervention Trial (SPRINT) at their baseline visit before randomization and sought to understand clinical factors predictive of these changes. Of the 9323 participants enrolled in SPRINT, 8662 had complete data for these analyses. The SBP after 1 minute of standing was subtracted from the mean value of the three preceding seated SBP values. At the baseline visit, medical history, medications, anthropometric measures, and standard laboratory testing were undertaken. The mean age of SPRINT participants was 68 years, two-thirds were male, with 30% black, 11% Hispanic, and 55% Caucasian. The spectrum of SBP changes on standing demonstrated that increases in SBP were as common as declines, and about 5% of participants had an increase, and 5% had a decrease of >20 mm Hg in SBP upon standing. Female sex, taller height, more advanced kidney disease, current smoking, and several drug classes were associated with larger declines in BP upon standing, while black race, higher blood levels of glucose and sodium, and heavier weight were associated with more positive values of the change in BP upon standing. Our cross-sectional results show a significant spectrum of orthostatic SBP changes, reflecting known (eg, age) and less well-known (eg, kidney function) relationships that may be important considerations in determining the optimal target blood pressure in long-term outcomes of older hypertensive patients.

Comparative outcomes of predominant facility-level use of ferumoxytol versus other intravenous iron formulations in incident hemodialysis patients.

BACKGROUND: Ferumoxytol was first approved for clinical use in 2009 solely based on data from trial comparisons with oral iron on biochemical anemia efficacy end points. To compare the rates of important patient outcomes (infection, cardiovascular events and death) between facilities predominantly using ferumoxytol versus iron sucrose (IS) or ferric gluconate (FG) in patients with end-stage renal disease (ESRD)-initiating hemodialysis (HD). METHODS: Using the United States Renal Data System, we identified all HD facilities that switched (almost) all patients from IS/FG to ferumoxytol (July 2009-December 2011). Each switching facility was matched with three facilities that continued IS/FG use. All incident ESRD patients subsequently initiating HD in these centers were studied and assigned their facility exposure. They were followed for all-cause mortality, cardiovascular hospitalization/death or infectious hospitalization/death. Follow-up ended at kidney transplantation, switch to peritoneal dialysis, transfer to another facility, facility switch to another iron formulation and end of database (31 December 2011). Cox proportional hazards regression was then used to estimate adjusted hazard ratios [HR (95% confidence intervals)]. RESULTS: In July 2009-December 2011, 278 HD centers switched to ferumoxytol; 265 units (95.3%) were matched with 3 units each that continued to use IS/FG. Subsequently, 14 206 patients initiated HD, 3752 (26.4%) in ferumoxytol and 10 454 (73.6%) in IS/FG centers; their characteristics were very similar. During 6433 person-years, 1929 all-cause, 726 cardiovascular and 191 infectious deaths occurred. Patients in ferumoxytol (versus IS/FG) facilities experienced similar all-cause [0.95 (0.85-1.07)], cardiovascular [0.99 (0.83-1.19)] and infectious mortality [0.88 (0.61-1.25)]. Among 5513 Medicare (Parts A + B) beneficiaries, cardiovascular events [myocardial infarction, stroke and cardiovascular death; 1.05 (0.79-1.39)] and infectious events [hospitalization/death; 0.96 (0.85-1.08)] did not differ between the iron exposure groups. CONCLUSIONS: In incident HD patients, ferumoxytol showed similar short- to mid-term safety profiles with regard to cardiovascular, infectious and mortality outcomes compared with the more commonly used intravenous iron formulations IS and FG.

Longer-term outcomes of darbepoetin alfa versus epoetin alfa in patients with ESRD initiating hemodialysis: a quasi-experimental cohort study.

BACKGROUND: Adequately powered studies directly comparing hard clinical outcomes of darbepoetin alfa (DPO) versus epoetin alfa (EPO) in patients undergoing dialysis are lacking. STUDY DESIGN: Observational, registry-based, retrospective cohort study; we mimicked a cluster-randomized trial by comparing mortality and cardiovascular events in US patients initiating hemodialysis therapy in facilities (almost) exclusively using DPO versus EPO. SETTING & PARTICIPANTS: Nonchain US hemodialysis facilities; each facility switching from EPO to DPO (2003-2010) was matched for location, profit status, and facility type with one EPO facility. Patients subsequently initiating hemodialysis therapy in these facilities were assigned their facility-level exposure. INTERVENTION: DPO versus EPO. OUTCOMES: All-cause mortality, cardiovascular mortality; composite of cardiovascular death, nonfatal myocardial infarction (MI), and nonfatal stroke. MEASUREMENTS: Unadjusted and adjusted HRs from Cox proportional hazards regression models. RESULTS: Of 508 dialysis facilities that switched to DPO, 492 were matched with a similar EPO facility; 19,932 (DPO: 9,465 [47.5%]; EPO: 10,467 [52.5%]) incident hemodialysis patients were followed up for 21,918 person-years during which 5,550 deaths occurred. Almost all baseline characteristics were tightly balanced. The demographics-adjusted mortality HR for DPO (vs EPO) was 1.06 (95% CI, 1.00-1.13) and was materially unchanged after adjustment for all other baseline characteristics (HR, 1.05; 95% CI, 0.99-1.12). Cardiovascular mortality did not differ between groups (HR, 1.05; 95% CI, 0.94-1.16). Nonfatal outcomes were evaluated among 9,455 patients with fee-for-service Medicare: 4,542 (48.0%) in DPO and 4,913 (52.0%) in EPO facilities. During 10,457 and 10,363 person-years, 248 and 372 events were recorded, respectively, for strokes and MIs. We found no differences in adjusted stroke or MI rates or their composite with cardiovascular death (HR, 1.10; 95% CI, 0.96-1.25). LIMITATIONS: Nonrandom treatment assignment, potential residual confounding. CONCLUSIONS: In incident hemodialysis patients, mortality and cardiovascular event rates did not differ between patients treated at facilities predominantly using DPO versus EPO.

Acute kidney injury after CABG versus PCI: an observational study using 2 cohorts.

BACKGROUND: Acute kidney injury (AKI) is a known complication after coronary revascularization, but few studies have directly compared the incidence of AKI after coronary artery bypass surgery (CABG) or after percutaneous coronary intervention (PCI) in similar patients. OBJECTIVES: The aim of this study was to investigate whether multivessel CABG compared with PCI as an initial revascularization strategy is associated with a higher risk for AKI. METHODS: A retrospective analysis of patients undergoing first documented coronary revascularization was conducted using 2 complementary cohorts: 1) Kaiser Permanente Northern California, a diverse, integrated health care delivery system; and 2) Medicare beneficiaries, a large, nationally representative older cohort. AKI was defined in the Kaiser Permanente Northern California cohort by an increase in serum creatinine of ≥0.3 mg/dl or ≥150% above baseline and in the Medicare cohort by discharge diagnosis codes and the use of dialysis. RESULTS: The incidence of AKI was 20.4% in the Kaiser Permanente Northern California cohort and 6.2% in the Medicare cohort. The incidence of AKI requiring dialysis was <1%. CABG was associated with a 2- to 3-fold significantly higher adjusted odds for developing AKI compared with PCI in both cohorts. CONCLUSIONS: AKI is common after multivessel coronary revascularization and is more likely after CABG than after PCI. The risk for AKI should be considered when choosing a coronary revascularization strategy, and ways to prevent AKI after coronary revascularization are needed.

Temporal trends in mortality after coronary artery revascularization in patients with end-stage renal disease.

BACKGROUND: Recent studies that have assessed the comparative effectiveness between coronary artery bypass grafting (CABG) and percutaneous coronary intervention (PCI) in patients with end-stage renal disease (ESRD) that have included analyses of temporal trends in mortality have noted mixed results. METHODS: We conducted an observational longitudinal cohort study of all adults with ESRD undergoing CABG or PCI within Kaiser Permanente Northern California. The primary predictor, index period of revascularization, was categorized into 3 periods: 1996-1999 (reference), 2000-2003, and 2004-2008, with the primary outcome being 3-year all-cause mortality. A multivariable Cox regression model with the assumption of independent censoring was used to determine the adjusted relative risk of the primary predictor. RESULTS: Among 1015 ESRD patients, 3-year mortality showed no significant change in the 2000-2003 period but was lower during the 2004-2008 period with an adjusted hazard ratio of 0.66 (95% confidence interval: 0.49-0.88; trend test p = 0.01). No change in 30-day mortality was noted. Further adjustment for receipt of medications at baseline and after revascularization did not materially affect risk estimates. No significant interactions were observed between the type of revascularization (CABG or PCI) and the period of the index revascularization. CONCLUSIONS: Among a high-risk cohort of patients with ESRD and coronary artery disease within Kaiser Permanente Northern California who were referred for coronary revascularization by either CABG or PCI, the relative risk of mortality in the 2004-2008 period decreased by 34% compared with the 1996-1999 period, with the benefit primarily in the decrease in late mortality.

Multivessel coronary revascularization and outcomes in kidney transplant recipients.

Coronary artery disease is a major cause of morbidity and mortality in the kidney transplant population. We compared the long-term outcomes of coronary artery bypass graft (CABG) surgery with percutaneous coronary intervention (PCI) for multivessel coronary disease in a contemporary cohort of US kidney transplant recipients. From the U.S. Renal Data System, we identified all adult kidney transplant patients with ≥6 months of Medicare A+B undergoing first recorded multivessel coronary revascularization from 1997 to 2009. The associations of CABG versus PCI with death and the composite of death or myocardial infarction (MI) were compared using proportional hazards regression. Of the 2272 patients included in the study, 1594 underwent CABG and 678 underwent PCI. The estimated 5-year survival rate was 55% [95% confidence interval (CI) 53% to 57%] following coronary revascularization, with no significant association between revascularization type and death [adjusted hazard ratio (aHR) = 1.08; CI 0.94-1.23] or the composite of death or MI (aHR = 1.07; CI 0.96-1.18). Separate propensity score-matched analyses yielded similar results. In this analysis of kidney transplant recipients undergoing multivessel coronary revascularization, we found no difference between CABG and PCI in terms of survival or the composite of death and MI.

Comparative effectiveness of multivessel coronary bypass surgery and multivessel percutaneous coronary intervention: a cohort study.

BACKGROUND: Randomized trials of coronary artery bypass graft (CABG) surgery and percutaneous coronary intervention (PCI) suggest that patient characteristics modify the effect of treatment on mortality. OBJECTIVE: To assess whether clinical characteristics modify the comparative effectiveness of CABG versus PCI in an unselected, general patient population. DESIGN: Observational treatment comparison using propensity score matching and Cox proportional hazards models. SETTING: United States, 1992 to 2008. PATIENTS: Medicare beneficiaries aged 66 years or older. INTERVENTION: Multivessel CABG or multivessel PCI. MEASUREMENTS: The CABG-PCI hazard ratio (HR) for all-cause mortality, with prespecified treatment-by-covariate interaction tests, and the absolute difference in life-years of survival in clinical subgroups after CABG or PCI, both over 5 years of follow-up. RESULTS: Among 105 156 propensity score-matched patients, CABG was associated with lower mortality than PCI (HR, 0.92 [95% CI, 0.90 to 0.95]; P < 0.001). Association of CABG with lower mortality was significantly greater (interaction P ≤ 0.002 for each) among patients with diabetes (HR, 0.88), a history of tobacco use (HR, 0.82), heart failure (HR, 0.84), and peripheral arterial disease (HR, 0.85). The overall predicted difference in survival between CABG and PCI treatment over 5 years was 0.053 life-years (range, -0.017 to 0.579 life-years). Patients with diabetes, heart failure, peripheral arterial disease, or tobacco use had the largest predicted differences in survival after CABG, whereas those with none of these factors had slightly better survival after PCI. LIMITATION: Treatments were chosen by patients and physicians rather than being randomly assigned. CONCLUSION: Multivessel CABG is associated with lower long-term mortality than multivessel PCI in the community setting. This association is substantially modified by patient characteristics, with improvement in survival concentrated among patients with diabetes, tobacco use, heart failure, or peripheral arterial disease. PRIMARY FUNDING SOURCE: National Heart, Lung, and Blood Institute.

Comparative effectiveness of coronary artery bypass grafting and percutaneous coronary intervention for multivessel coronary disease in a community-based population with chronic kidney disease.

BACKGROUND: Randomized clinical trials comparing coronary artery bypass grafting (CABG) with percutaneous coronary intervention (PCI) have largely excluded patients with chronic kidney disease (CKD), leading to uncertainty about the optimal coronary revascularization strategy. We sought to test the hypothesis that an initial strategy of CABG would be associated with lower risks of long-term mortality and cardiovascular morbidity compared with PCI for the treatment of multivessel coronary heart disease in the setting of CKD. METHODS: We created a propensity score-matched cohort of patients aged ≥30 years with no prior dialysis or renal transplant who received multivessel coronary revascularization between 1996 and 2008 within a large integrated health care delivery system in northern California. We used extended Cox regression to examine death from any cause, acute coronary syndrome, and repeat revascularization. RESULTS: Coronary artery bypass grafting was associated with a significantly lower adjusted rate of death than PCI across all strata of estimated glomerular filtration rate (eGFR) (in mL/min per 1.73 m(2)): the adjusted hazard ratio (HR) was 0.81, 95% CI 0.68 to 1.00 for patients with eGFR ≥60; HR 0.73 (CI 0.56-0.95) for eGFR of 45 to 59; and HR 0.87 (CI 0.67-1.14) for eGFR <45. Coronary artery bypass grafting was also associated with significantly lower rates of acute coronary syndrome and repeat revascularization at all levels of eGFR compared with PCI. CONCLUSIONS: Among adults with and without CKD, multivessel CABG was associated with lower risks of death and coronary events compared with multivessel PCI.

Risk factors for ESRD in individuals with preserved estimated GFR with and without albuminuria: results from the Kidney Early Evaluation Program (KEEP).

BACKGROUND: Given the increasing costs and poor outcomes of end-stage renal disease (ESRD), we sought to identify risk factors for ESRD in people with preserved estimated glomerular filtration rate (eGFR), with or without albuminuria, who were at high risk of ESRD. METHODS: This cohort study included participants in the National Kidney Foundation's Kidney Early Evaluation Program (KEEP) with eGFR ≥ 60 mL/min/1.73 m(2) at baseline stratified by the presence or absence of albuminuria. The Chronic Kidney Disease Epidemiology Collaboration equation was used to calculate eGFR. Urine was tested for albuminuria by semiquantitative dipstick. The outcome was the development of treated chronic kidney failure, defined as initiation of maintenance dialysis therapy or kidney transplantation, determined by linkage to the US Renal Data System. We used a Cox model with the Fine-Gray method to assess risk factors for treated chronic kidney failure while accounting for the competing risk of death. RESULTS: During a median follow-up of 4.8 years, 126 of 13,923 participants with albuminuria (16/10,000 patient-years) and 56 of 109,135 participants without albuminuria (1.1/10,000 patient-years) developed treated chronic kidney failure. Diabetes was a strong risk factor for developing treated chronic kidney failure in participants with and without albuminuria (adjusted HRs of 9.3 [95% CI, 5.7-15.3] and 7.8 [95% CI, 4.1-14.8], respectively). Black race, lower eGFR, and higher systolic blood pressure also were associated with higher adjusted risks of developing treated chronic kidney failure. CONCLUSIONS: In a diverse high-risk cohort of KEEP participants with preserved eGFR, we showed that diabetes, higher systolic blood pressure, lower eGFR, and black race were risk factors for developing treated chronic kidney failure irrespective of albuminuria status, although the absolute risk of kidney failure in participants without albuminuria was very low. Our findings support testing for kidney disease in high-risk populations, which often have otherwise unrecognized kidney disease.

Multivessel coronary artery bypass grafting versus percutaneous coronary intervention in ESRD.

Thirty to sixty percent of patients with ESRD on dialysis have coronary heart disease, but the optimal strategy for coronary revascularization is unknown. We used data from the United States Renal Data System to define a cohort of 21,981 patients on maintenance dialysis who received initial coronary revascularization with either coronary artery bypass grafting (CABG) or percutaneous coronary intervention (PCI) between 1997 and 2009 and had at least 6 months of prior Medicare coverage as their primary payer. The primary outcome was death from any cause, and the secondary outcome was a composite of death or myocardial infarction. Overall survival rates were consistently poor during the study period, with unadjusted 5-year survival rates of 22%-25% irrespective of revascularization strategy. Using multivariable-adjusted proportional hazards regression, we found that CABG compared with PCI associated with significantly lower risks for both death (HR=0.87, 95% CI=0.84-0.90) and the composite of death or myocardial infarction (HR=0.88, 95% CI=0.86-0.91). Results were similar in analyses using a propensity score-matched cohort. In the absence of data from randomized trials, these results suggest that CABG may be preferred over PCI for multivessel coronary revascularization in appropriately selected patients on maintenance dialysis.