Sex Differences in Cardiovascular Outcomes in Patients With Kidney Failure.

BACKGROUND: Cardiovascular disease is the leading cause of mortality in patients with kidney failure, and their risk of cardiovascular events is 10 to 20 times higher as compared with the general population. METHODS AND RESULTS: We evaluated 508 822 patients who initiated dialysis between January 1, 2005 and December 31, 2014 using the United States Renal Data System with linked Medicare claims. We determined hospitalization rates for cardiovascular events, defined by acute coronary syndrome, heart failure, and stroke. We examined the association of sex with outcome of cardiovascular events, cardiovascular death, and all-cause death using adjusted time-to-event models. The mean age was 70±12 years and 44.7% were women. The cardiovascular event rate was 232 per thousand person-years (95% CI, 231-233), with a higher rate in women than in men (248 per thousand person-years [95% CI, 247-250] versus 219 per thousand person-years [95% CI, 217-220]). Women had a 14% higher risk of cardiovascular events than men (hazard ratio [HR], 1.14 [95% CI, 1.13-1.16]). Women had a 16% higher risk of heart failure (HR, 1.16 [95% CI, 1.15-1.18]), a 31% higher risk of stroke (HR, 1.31 [95% CI, 1.28-1.34]), and no difference in risk of acute coronary syndrome (HR, 1.01 [95% CI, 0.99-1.03]). Women had a lower risk of cardiovascular death (HR, 0.89 [95% CI, 0.88-0.90]) and a lower risk of all-cause death than men (HR, 0.96 [95% CI, 0.95-0.97]). CONCLUSIONS: Among patients undergoing dialysis, women have a higher risk of cardiovascular events of heart failure and stroke than men. Women have a lower adjusted risk of cardiovascular mortality and all-cause mortality.

Pregnancies in Women With Kidney Failure on Home Dialysis in the United States.

Introduction: Women with kidney failure have impaired fertility and are at a higher risk of maternal and fetal morbidity and mortality. Little is known about pregnancies in women receiving maintenance home dialysis in the United States. Methods: Using data from the United States Renal Data System (USRDS), a cohort of 26,387 women aged 15 to 49 years with kidney failure receiving maintenance home dialysis from 2005 to 2018 was examined. We calculated pregnancy rates and identified factors, including the modality associated with pregnancy receiving home dialysis. Results: Overall, 437 pregnancies were identified in 26,837 women on home dialysis. The unadjusted pregnancy rate was 8.6 per 1000 person-years (PTPY). The unadjusted pregnancy rate was higher on home hemodialysis (16.0 vs. 7.5 PTPY) than on peritoneal dialysis. Women receiving home hemodialysis had a higher adjusted likelihood of pregnancy than women receiving peritoneal dialysis (hazard ratio [HR], 2.34; 95% confidence interval [CI], 1.79-3.05). Compared with women aged 20 to 24 years, the likelihood of pregnancy was lower in women aged 30 to 34 years (HR, 0.64; 95% CI, 0.43-0.96), 35 to 39 years (HR, 0.53; 95% CI, 0.35-0.79), 40 to 44 years (HR, 0.32; 95% CI, 0.21-0.49), and 45 to 49 years (HR, 0.21; 95% CI, 0.13-0.33). Whereas Black women had a higher likelihood of pregnancy (HR, 1.40; 95% CI, 1.07-1.83), there was no difference in likelihood of pregnancy in Asian, Hispanic, and Native Americans as compared to Whites. Body mass index, cause of kidney failure, socioeconomic status, rurality, predialysis nephrology care, or dialysis vintage were not significantly associated with pregnancy on home dialysis. Conclusion: The pregnancy rate in women with kidney failure undergoing home dialysis is higher with home hemodialysis than with peritoneal dialysis. Younger age and Black race or ethnicity are associated with a higher likelihood of pregnancy among women receiving home dialysis. This information can guide clinicians in preconception counselling and making informed treatment decisions for pregnant women on home dialysis.

A clinical score to predict recovery in end-stage kidney disease due to acute kidney injury.

Background: Acute kidney injury (AKI) is a major contributor to end-stage kidney disease (ESKD). About one-third of patients with ESKD due to AKI recover kidney function. However, the inability to accurately predict recovery leads to improper triage of clinical monitoring and impacts the quality of care in ESKD. Methods: Using data from the United States Renal Data System from 2005 to 2014 (n = 22 922), we developed a clinical score to predict kidney recovery within 90 days and within 12 months after dialysis initiation in patients with ESKD due to AKI. Multivariable logistic regressions were used to examine the effect of various covariates on the primary outcome of kidney recovery to develop the scoring system. The resulting logistic parameter estimates were transformed into integer point totals by doubling and rounding the estimates. Internal validation was performed. Results: Twenty-four percent and 34% of patients with ESKD due to AKI recovered kidney function within 90 days and 12 months, respectively. Factors contributing to points in the two scoring systems were similar but not identical, and included age, race/ethnicity, body mass index, congestive heart failure, cancer, amputation, functional status, hemoglobin and prior nephrology care. Three score categories of increasing recovery were formed: low score (0-6), medium score (7-9) and high score (10-12), which exhibited 90-day recovery rates of 12%, 26% and 57%. For the 12-month scores, the low, medium and high groups consisted of scores 0-5, 6-8 and 9-11, with 12-month recovery rates of 16%, 33% and 62%, respectively. The internal validation assessment showed no overfitting of the models. Conclusion: A clinical score derived from information available at incident dialysis predicts renal recovery at 90 days and 12 months in patients with presumed ESKD due to AKI. The score can help triage appropriate monitoring to facilitate recovery and begin planning long-term dialysis care for others.

Can a best practice advisory improve anticoagulation prescribing to reduce stroke risk in patients with atrial fibrillation?

BACKGROUND: Atrial fibrillation (AF) is the most common cardiac rhythm disorder and a risk factor for stroke. Randomized trials have demonstrated that anticoagulation can reduce strokes in AF patients. Yet, widespread underutilization of this therapy continues. To address this practice gap, we designed a study to implement and evaluate the effectiveness of a best practice advisory (BPA) for an Atrial Fibrillation Decision Support Tool (AFDST) embedded within our electronic health record. METHODS: Our intervention is provider-facing, focused on decision support. Clinical setting is ambulatory patients being seen by primary care physicians. We prospectively enrolled 608 patients in our health system who are currently receiving less than optimal anticoagulation therapy as determined by the AFDST and randomized them to one of two arms - 1) usual care, in which the AFDST is available for use; or 2) addition of a BPA to the AFDST notifying clinicians that their patient stands to gain significant benefit from a change in current therapy. Primary outcome was effectiveness of the BPA measured by change to "appropriate thromboprophylaxis" based on the AFDST recommendation at 3 months post-enrollment. Secondary endpoints included Reach and Adoption from the RE-AIM (Reach, Effectiveness, Adoption, Implementation, & Maintenance) framework for implementation studies. RESULTS: Among 562 patients with a minimum follow-up of 3 months, addition of a BPA to the AFDST resulted in significant improvement in anticoagulation therapy, 5 % (12/248) versus 11 % (33/314) p = 0.02, odds ratio 2.31 (95 % CI, 1.17-4.87). CONCLUSIONS: A BPA added to an AF decision support tool improved anticoagulation therapy among AF patients in a primary care academic health system setting.

Electronic health record-embedded decision support to reduce stroke risk in patients with atrial fibrillation - Study protocol.

BACKGROUND: Atrial fibrillation (AF) is the most common significant cardiac rhythm disorder and is a powerful common risk factor for stroke. Randomized trials have demonstrated that anticoagulation can reduce the risk of stroke in patients with AF. Yet, there continues to be widespread underutilization of this therapy. To address this practice gap locally and improve efforts to reduce the risk of stroke for patients with AF in our health system, we have designed a study to implement and evaluate the effectiveness of an Atrial Fibrillation Decision Support Tool (AFDST) embedded within our electronic health record. METHODS: Our intervention is provider-facing and focused on decision support. The clinical setting is ambulatory patients being seen by primary care physicians. Patients include those with both incident and prevalent AF. This randomized, prospective trial will enroll 800 patients in our University of Cincinnati Health System who are currently receiving less than optimal anticoagulation therapy as determined by the AFDST. Patients will be randomized to one of two arms - 1) usual care, in which the AFDST is available for use; 2) addition of a best practice advisory (BPA) to the AFDST notifying the clinician that their patient stands to gain a significant benefit from a change in their current thromboprophylactic therapy. RESULTS: The primary outcome is effectiveness of the BPA measured by change to "appropriate thromboprophylaxis" based on the AFDST recommendation at 3 months post randomization. Secondary endpoints include Reach and Adoption, from the RE-AIM framework for implementation studies. Sample size is based upon an improvement from inappropriate to appropriate anticoagulation therapy estimated at 4% in the usual care arm and ≥10% in the experimental arm. CONCLUSION: Our goal is to examine whether addition of a BPA to an AFDST focused on primary care physicians in an ambulatory care setting will improve "appropriate thromboprophylaxis" compared with usual care. Results will be examined at 3 months post randomization and at the end of the study to evaluate durability of changes. We expect to complete patient enrollment by the end of June 2022. TRIAL REGISTRATION: Clinicaltrials.gov NCT04099485.

Racial and sex differences in optimizing anticoagulation therapy for patients with atrial fibrillation.

Study objective: Atrial fibrillation (AF) is the most common cardiac rhythm disorder, responsible for 15 % of strokes in the United States. Studies continue to document underuse of anticoagulation therapy in minority populations and women. Our objective was to compare the proportion of AF patients by race and sex who were receiving non-optimal anticoagulation as determined by an Atrial Fibrillation Decision Support Tool (AFDST). Design setting and participants: Retrospective cohort study including 14,942 patients within University of Cincinnati Health Care system. Data were analyzed between November 18, 2020, and November 20, 2021. Main outcomes and measures: Discordance between current therapy and that recommended by the AFDST. Results: In our two-category analysis 6107 (41 %) received non-optimal anticoagulation therapy, defined as current treatment category ≠ AFDST-recommended treatment category. Non-optimal therapy was highest in Black (42 % [n = 712]) and women (42 % [n = 2668]) and lower in White (39 % [n = 4748]) and male (40 % [n = 3439]) patients. Compared with White patients, unadjusted and adjusted odds ratios of receiving non-optimal anticoagulant therapy for Black patients were 1.13; 95 % CI, 1.02-1.30, p = 0.02; and 1.17; 95%CI, 1.04-1.31, p = 0.01; respectively, and 1.10; 95 % CI 1.03-1.18, p = 0.005; and 1.36; 95 % CI, 1.25-1.47, p < 0.001; for females compared with males. Conclusions and relevance: In patients with atrial fibrillation in the University of Cincinnati Health system, Black race and female sex were independently associated with an increased odds of receiving non-optimal anticoagulant therapy.

Contraceptive Use Among Women With End-Stage Kidney Disease on Dialysis in the United States.

RATIONALE & OBJECTIVE: Although end-stage kidney disease (ESKD) adversely affects fertility, pregnancies can occur among women receiving dialysis. ESKD increases the risk for adverse pregnancy outcomes and little is known about contraceptive use in women undergoing dialysis. STUDY DESIGN: Retrospective cohort study. SETTING & PARTICIPANTS: Using the US Renal Data System covering January 1, 2005, through December 31, 2014, we evaluated for each calendar year women who for the entire year were aged 15 to 44 years, receiving dialysis, and with Medicare as the primary payer. PREDICTORS: Age, race/ethnicity, and calendar year of prevalent ESKD. OUTCOME: Contraceptive use. ANALYTIC APPROACH: We determined rates of contraceptive use and used multivariable logistic regression to identify factors associated with contraceptive use. RESULTS: The study cohort included 35,732 women and represented 115,713 person-years. The rate of contraceptive use was 5.30% of person-years (95% CI, 5.17%-5.42%). Overall, contraceptive use increased from 2005 to 2014 (4.21%; 95% CI, 3.84%-4.59% vs 6.54%, 95% CI, 6.10%-6.99%). Compared with women aged 25 to 29 years, contraceptive use was higher in women aged 15 to 24 years (OR, 1.30; 95% CI, 1.18-1.43) and lower in women aged 30 to 34 years (OR, 0.74; 95% CI, 0.68-0.81), 35 to 39 years (OR, 0.46; 95% CI, 0.42-0.50), and 40 to 44 years (OR, 0.30; 95% CI, 0.27-0.34). Compared with White women, contraceptive use was higher in Black (OR, 1.12; 95% CI, 1.02-1.24) and Native American women (OR, 1.60; 95% CI, 1.25-2.05). Women with ESKD due to glomerulonephritis had a higher likelihood of contraceptive use than women with ESKD due to diabetes (OR, 1.22; 95% CI, 1.06-1.42). Women receiving peritoneal dialysis had a lower likelihood of contraceptive use than women receiving hemodialysis (OR, 0.85; 95% CI, 0.78-0.93). Compared with women without predialysis nephrology care, contraceptive use was higher in women who received predialysis nephrology care for 12 or fewer months (OR, 1.22; 95% CI, 1.09-1.37) and more than 12 months (OR, 1.33; 95% CI, 1.20-1.47). LIMITATIONS: Retrospective design and use of administrative data. CONCLUSIONS: Among women with ESKD undergoing dialysis, contraceptive use remains low at 5.30%. Younger age, Native American and Black race/ethnicity, ESKD due to glomerulonephritis, hemodialysis, and predialysis nephrology care are associated with a higher likelihood of contraceptive use. The study highlights the importance of prepregnancy counseling for contraceptive use in women receiving dialysis.

Mortality and Recovery Associated with Kidney Failure due to Acute Kidney Injury.

BACKGROUND AND OBJECTIVES: AKI requiring dialysis is a contributor to the growing burden of kidney failure, yet little is known about the frequency and patterns of recovery of AKI and its effect on outcomes in patients on incident dialysis. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: Using the US Renal Data System, we evaluated a cohort of 1,045,540 patients on incident dialysis from January 1, 2005 to December 31, 2014, retrospectively. We examined the association of kidney failure due to AKI with the outcome of all-cause mortality and the associations of sex and race with kidney recovery. RESULTS: Mean age was 63±15 years, and 32,598 (3%) patients on incident dialysis had kidney failure due to AKI. Compared with kidney failure due to diabetes mellitus, kidney failure attributed to AKI was associated with a higher mortality in the first 0-3 months following dialysis initiation (adjusted hazard ratio, 1.28; 95% confidence interval, 1.24 to 1.32) and 3-6 months (adjusted hazard ratio, 1.16; 95% confidence interval, 1.11 to 1.20). Of the patients with kidney failure due to AKI, 11,498 (35%) eventually recovered their kidney function, 95% of those within 12 months. Women had a lower likelihood of kidney recovery than men (adjusted hazard ratio, 0.86; 95% confidence interval, 0.83 to 0.90). Compared with whites, blacks (adjusted hazard ratio, 0.68; 95% confidence interval, 0.64 to 0.72), Asians (adjusted hazard ratio, 0.82; 95% confidence interval, 0.69 to 0.96), Hispanics (adjusted hazard ratio, 0.82; 95% confidence interval, 0.76 to 0.89), and Native Americans (adjusted hazard ratio, 0.72; 95% confidence interval, 0.54 to 0.95) had lower likelihoods of kidney recovery. CONCLUSIONS: Kidney failure due to AKI confers a higher risk of mortality in the first 6 months compared with kidney failure due to diabetes or other causes. Recovery within 12 months is common, although less so among women than men and among black, Asian, Hispanic, and Native American patients than white patients.

Pregnancy-Related Acute Kidney Injury in the United States: Clinical Outcomes and Health Care Utilization.

BACKGROUND: Acute kidney injury (AKI) during pregnancy is a public health problem and is associated with maternal and fetal morbidity and mortality. Clinical outcomes and health care utilization in pregnancy-related AKI, especially in women with diabetes, are not well studied. METHODS: Using data from the 2006 to 2015 Nationwide Inpatient Sample, we identified 42,190,790 pregnancy-related hospitalizations in women aged 15-49 years. We determined factors associated with AKI, including race/ethnicity, and associations between AKI and inpatient mortality, and between AKI and cardiovascular (CV) events, during pregnancy-related hospitalizations. We calculated health care expenditures from pregnancy-related AKI hospitalizations. RESULTS: Overall, the rate of AKI during pregnancy-related hospitalizations was 0.08%. In the adjusted regression analysis, a higher likelihood of AKI during pregnancy-related hospitalizations was seen in 2015 (OR 2.20; 95% CI 1.89-2.55) than in 2006; in older women aged 36-40 years (OR 1.49; 95% CI 1.36-1.64) and 41-49 years (OR 2.12; 95% CI 1.84-2.45) than in women aged 20-25 years; in blacks (OR 1.52; 95% CI 1.40-1.65) and Native Americans (OR 1.45; 95% CI 1.10-1.91) than in whites, and in diabetic women (OR 4.43; 95% CI 4.04-4.86) than in those without diabetes. Pregnancy-related hospitalizations with AKI were associated with a higher likelihood of inpatient mortality (OR 13.50; 95% CI 10.47-17.42) and CV events (OR 9.74; 95% CI 9.08-10.46) than were hospitalizations with no AKI. The median cost was higher for a delivery hospitalization with AKI than without AKI (USD 18,072 vs. 4,447). CONCLUSION: The rates of pregnancy-related AKI hospitalizations have increased during the last decade. Factors associated with a higher likelihood of AKI during pregnancy included older age, black and Native American race/ethnicity, and diabetes. Hospitalizations with pregnancy-related AKI have an increased risk of inpatient mortality and CV events, and a higher health care utilization than do those without AKI.

Bariatric Surgery is Associated With Reduced Risk of Breast Cancer in Both Premenopausal and Postmenopausal Women.

OBJECTIVE: This retrospective cohort study examined whether bariatric surgery is associated with reduced risk of breast cancer among pre- and postmenopausal women. BACKGROUND: Obesity is associated with increased risk of breast cancer, but the impact of weight loss on breast cancer risk has been difficult to quantify. METHODS: The cohort included obese (body mass index ≥35 kg/m) patients enrolled in an integrated health care delivery system between 2005 and 2012 (with follow-up through 2014). Female bariatric surgery patients (N = 17,998) were matched on body mass index, age, study site, and comorbidity index to 53,889 women with no bariatric surgery. Kaplan-Meier curves and Cox proportional hazards models were used to examine incident breast cancer up to 10 years after bariatric surgery. Pre- and postmenopausal women were examined separately, and further classified by estrogen receptor (ER) status. RESULTS: The analysis included 301 premenopausal and 399 postmenopausal breast cancer cases. In multivariable adjusted models, bariatric surgery was associated with a reduced risk of both premenopausal (HR = 0.72, 95% CI, 0.54-0.94) and postmenopausal (HR = 0.55, 95% CI, 0.42-0.72) breast cancer. Among premenopausal women, the effect of bariatric surgery was more pronounced among ER-negative cases (HR = 0.36, 95% CI, 0.16-0.79). Among postmenopausal women, the effect was more pronounced in ER-positive cases (HR = 0.52, 95% CI, 0.39-0.70). CONCLUSIONS: Bariatric surgery was associated with a reduced risk of breast cancer among severely obese women. These findings have significant public health relevance because the prevalence of obesity continues to rise, and few modifiable breast cancer risk factors have been identified, especially for premenopausal women.

Racial Differences and Factors Associated with Pregnancy in ESKD Patients on Dialysis in the United States.

BACKGROUND: Pregnancy in women with ESKD undergoing dialysis is uncommon due to impaired fertility. Data on pregnancy in women on dialysis in the United States is scarce. METHODS: We evaluated a retrospective cohort of 47,555 women aged 15-44 years on dialysis between January 1, 2005 and December 31, 2013 using data from the United States Renal Data System with Medicare as primary payer. We calculated pregnancy rates and identified factors associated with pregnancy. RESULTS: In 47,555 women on dialysis, 2352 pregnancies were identified. Pregnancy rate was 17.8 per thousand person years (PTPY) with the highest rate in women aged 20-24 (40.9 PTPY). In the adjusted time-to-event analysis, a higher likelihood of pregnancy was seen in Native American (HR, 1.77; 95% CI, 1.33 to 2.36), Hispanic (HR, 1.51; 95% CI, 1.32 to 1.73), and black (HR, 1.33; 95% CI, 1.18 to 1.49) women than in white women. A higher rate of pregnancy was seen in women with ESKD due to malignancy (HR, 1.64; 95% CI, 1.27 to 2.12), GN (HR, 1.38; 95% CI, 1.21 to 1.58), hypertension (HR, 1.32; 95% CI, 1.16 to 1.51), and secondary GN/vasculitis (HR, 1.18; 95% CI, 1.02 to 1.37) than ESKD due to diabetes. A lower likelihood of pregnancy was seen among women on peritoneal dialysis than on hemodialysis (HR, 0.47; 95% CI, 0.41 to 0.55). CONCLUSIONS: The pregnancy rate is higher in women on dialysis than previous reports indicate. A higher likelihood of pregnancy was associated with race/ethnicity, ESKD cause, and dialysis modality.

Racial disparities and factors associated with pregnancy in kidney transplant recipients in the United States.

BACKGROUND: Although kidney transplant improves reproductive function in women with end-stage kidney disease (ESKD), pregnancy in kidney transplant recipients' remains challenging due to the risk of adverse maternal and fetal outcomes. METHODS: We evaluated a retrospective cohort of 7,966 women who were aged 15-45 years and received a kidney transplant between January 1, 2005 and December 31, 2011 from the United States Renal Data System with Medicare as the primary payer for the entire three years after the date of transplantation. Unadjusted and adjusted rates of pregnancy in the first three post-transplant years were calculated, using Poisson regression for the adjustment. Factors associated with pregnancy, including race, were examined using logistic regression. RESULTS: Overall, 293 pregnancies were identified in 7966 women. The unadjusted pregnancy rate was 13.8 per thousand person-years (PTPY) (95% confidence interval (CI), 12.3-15.5). Pregnancy rates were roughly constant in the years 2005-2011 except in 2005 and 2010. The rate of pregnancy was highest in Hispanic women (21.4 PTPY; 95% CI, 17.2-26.4) and Hispanic women had a higher likelihood of pregnancy as compared to white women (OR, 1.56; CI, 1.12-2.16). Pregnancy rates were lowest in women aged 30-34 years and 35-45 years at transplant, and women aged 30-34 years and 35-45 years at transplant were less likely to ever become pregnant during the follow-up (odds ratio [OR], 0.69; CI, 0.49-0.98 and OR, 0.14; CI 0.09-0.21 respectively) as compared to women aged 25-29 years at time of transplant. Women had higher rates of pregnancy in the second and third-year post-transplant (16.0 PTPY, CI 13.2-19.2 and 16.9 PTPY, CI 14.0-20.4) than in the first-year post-transplant (9.0 PTPY, CI 7.0-11.4). In transplant recipients, pregnancy was more likely in women with ESKD due to cystic disease (OR, 2.42; CI, 1.02-5.74) or glomerulonephritis (OR, 2.14; CI, 1.07-4.31) as compared to women with ESKD due to diabetes. CONCLUSION: Hispanic race, younger age, and ESKD cause due to cystic disease or glomerulonephritis are significant factors associated with a higher likelihood of pregnancy. Pregnancy rates have been fairly constant over the last decade. This study improves our understanding of factors associated with pregnancy in kidney transplant recipients.

Temporal Trends in Incident Mortality in Dialysis Patients: Focus on Sex and Racial Disparities.

BACKGROUND: Racial minorities and women constitute substantial portions of the incident and prevalent end-stage renal disease (ESRD) population in the United States. Although ESRD is characterized by high mortality, temporal trends, and race and sex differences in mortality have not been studied. METHODS: We evaluated 944,650 adult patients who initiated dialysis between January 1, 2005 and December 31, 2014, using the United States Renal Data System, for sex-related and race-related trends in mortality. Logistic regression models adjusted for pre-dialysis health status were used to examine associations among the predictors' sex, race, and year of incident dialysis, and the outcome all-cause mortality at 1-year post ESRD. RESULTS: The mean age was 65 ± 14 years. The 1-year crude mortality rates in incident ESRD patients decreased by 28% from 2004 to 2015. Risk-adjusted 1-year mortality decreased by 3% for each later year of incident ESRD (p < 0.001). In general, from 2005 to 2014, mortality rates decreased across both sexes, and all races. White patients experienced the lowest reduction in adjusted 1-year mortality rates (16%). While women experienced a survival advantage over men in 2005, by 2014 it was reversed to survival advantage for men. Combining all years, the adjusted risk of dying at 1-year after initiating dialysis was lower in women than men (OR 0.98; 95% CI 0.97-0.99), and as compared to whites, was lower in blacks (OR 0.73; 95% CI -0.72-0.74), Hispanics (OR 0.64; 95% CI 0.63-0.65), Asians (OR 0.55; 95% CI 0.53-0.56), and Native Americans (OR 0.67; 95% CI 0.63-0.71). CONCLUSION: The 1-year mortality rates among patients with ESRD have decreased steadily during a recent 10-year period across both men and women, and in all 5 races. Women have only a 2% lower risk of dying at 1-year after dialysis initiation than men. White patients had higher mortality as compared to other races. Our results suggest the need for sex, and race-specific treatment strategies in ESRD care.

Pre-dialysis acute care hospitalizations and clinical outcomes in dialysis patients.

BACKGROUND: Patients with chronic kidney disease (CKD), a precursor of end stage renal disease (ESRD), face an increasing burden of hospitalizations. Although mortality on dialysis is highest during the first year, the impact of pre-dialysis acute hospitalizations on clinical outcomes in dialysis patients remains unknown. METHODS: We evaluated 170,897 adult patients who initiated dialysis between 1/1/2010 and 12/31/2014 with linked Medicare claims from the United States Renal Data System. Using logistic regression models, we examined the association of 2-year pre-dialysis hospitalization on the primary outcome of 1-year all-cause mortality. Secondary outcomes included 90-day mortality, type of initial dialysis modality and type of vascular access at hemodialysis initiation. RESULTS: Mean age was 72.7 ± 11.0 years. In the study sample, 76.0% of patients had at least one pre-dialysis hospitalization. Compared to patients with no pre-dialysis hospitalization, the adjusted 1-year mortality was higher with pre-dialysis cardiovascular related hospitalization (odds ratio [OR], 1.63; 95% confidence interval [CI], 1.57-1.68), infection related hospitalization (OR, 1.51; CI, 1.45-1.57), both cardiovascular and infection hospitalization (OR, 1.91; CI, 1.83-1.99), and neither-cardiovascular nor-infection hospitalization (OR, 1.23; CI, 1.19-1.27). Additionally, the adjusted odds of hemodialysis vs. peritoneal dialysis as the initial dialysis modality were higher, whereas adjusted odds to initiate hemodialysis with an arteriovenous access vs. central venous catheter were lower in patients with any type of hospitalization. CONCLUSION: Pre-dialysis hospitalization is an independent predictor of 1-year mortality in dialysis patients. Reducing the risk of pre-dialysis hospitalization may provide opportunities to improve quality of care in ESRD.

Bariatric Surgery and the Risk of Cancer in a Large Multisite Cohort.

OBJECTIVE: To determine whether bariatric surgery is associated with a lower risk of cancer. BACKGROUND: Obesity is strongly associated with many types of cancer. Few studies have examined the relationship between bariatric surgery and cancer risk. METHODS: We conducted a retrospective cohort study of patients undergoing bariatric surgery between 2005 and 2012 with follow-up through 2014 using data from a large integrated health insurance and care delivery systems with 5 study sites. The study included 22,198 subjects who had bariatric surgery and 66,427 nonsurgical subjects matched on sex, age, study site, body mass index, and Elixhauser comorbidity index. Multivariable Cox proportional-hazards models were used to examine incident cancer up to 10 years after bariatric surgery compared to the matched nonsurgical patients. RESULTS: After a mean follow-up of 3.5 years, we identified 2543 incident cancers. Patients undergoing bariatric surgery had a 33% lower hazard of developing any cancer during follow-up [hazard ratio (HR) 0.67, 95% confidence interval (CI) 0.60, 0.74, P < 0.001) compared with matched patients with severe obesity who did not undergo bariatric surgery, and results were even stronger when the outcome was restricted to obesity-associated cancers (HR 0.59, 95% CI 0.51, 0.69, P < 0.001). Among the obesity-associated cancers, the risk of postmenopausal breast cancer (HR 0.58, 95% CI 0.44, 0.77, P < 0.001), colon cancer (HR 0.59, 95% CI 0.36, 0.97, P = 0.04), endometrial cancer (HR 0.50, 95% CI 0.37, 0.67, P < 0.001), and pancreatic cancer (HR 0.46, 95% CI 0.22, 0.97, P = 0.04) was each statistically significantly lower among those who had undergone bariatric surgery compared with matched nonsurgical patients. CONCLUSIONS: In this large, multisite cohort of patients with severe obesity, bariatric surgery was associated with a lower risk of incident cancer, particularly obesity-associated cancers, such as postmenopausal breast cancer, endometrial cancer, and colon cancer. More research is needed to clarify the specific mechanisms through which bariatric surgery lowers cancer risk.

Gender and Racial Disparities in Initial Hemodialysis Access and Outcomes in Incident End-Stage Renal Disease Patients.

BACKGROUND: Arteriovenous (AV) access confers survival benefits over central venous catheters (CVC) in hemodialysis patients. Although chronic kidney disease disproportionately affects women and racial minorities, disparities in the -utilization of hemodialysis access across Asians, Native Americans, Hispanics, blacks, and whites among males and females after accounting for pre-dialysis health are not well studied. METHODS: We evaluated 885,699 patients with end-stage renal disease who initiated hemodialysis between January 1, 2004 and December 31, 2014 using the US Renal Data System. Multivariable logistic regression models -adjusted for pre-dialysis health were used to test the associations between gender and race on type of vascular access (AV access vs. CVC, and AV fistula vs. AV graft) at hemodialysis initiation as primary outcome, and on 1-year mortality as a secondary outcome. RESULTS: Mean age was 65 ± 14 years. Females were less likely to use AV access for hemodialysis initiation than were males (OR 0.85; 95% CI 0.84-0.86). Compared to whites, adjusted odds of AV access for hemodialysis initiation were higher in blacks (OR 1.08; 95% CI 1.07-1.70), Asians (OR 1.11; 95% CI 1.07-1.14); and lower in Hispanics (OR 0.89; 95% CI 0.87-0.90). There was no -significant difference in mortality between males and females. Compared to whites, 1-year adjusted mortality was lower in Asians (OR 0.55; 95% CI 0.53-0.56), blacks (OR 0.67; 95% CI 0.66-0.68), Hispanics (OR 0.62; 95% CI 0.61-0.63), and Native Americans (OR 0.62; 95% CI 0.58-0.66). CONCLUSION: Females had lower odds of using AV access than do males for hemodialysis initiation. As compared to whites, blacks and Asians were more likely, and Hispanics were less likely to use AV access for first outpatient hemodialysis. Further investigation of biological and process of care factors may help in developing ways to reduce these disparities.