Equitable Care for Hypertension: Blood Pressure and Patient-Reported Outcomes of the RICH LIFE Cluster Randomized Trial.

BACKGROUND: Disparities in hypertension control are well documented but underaddressed. METHODS: RICH LIFE (Reducing Inequities in Care of Hypertension: Lifestyle Improvement for Everyone) was a 2-arm, cluster randomized trial comparing the effect on blood pressure (BP) control (systolic BP ≤140 mm Hg, diastolic BP ≤90 mm Hg), patient activation, and disparities in BP control of 2 multilevel interventions, standard of care plus (SCP) and collaborative care/stepped care (CC/SC). SCP included BP measurement standardization, audit and feedback, and equity-leadership training. CC/SC added roles to address social or medical needs. Primary outcomes were BP control and patient activation at 12 months. Generalized estimating equations and mixed-effects regression models with fixed effects of time, intervention, and their interaction compared change in outcomes at 12 months from baseline. RESULTS: A total of 1820 adults with uncontrolled BP and ≥1 other risk factors enrolled in the study. Their mean age was 60.3 years, and baseline BP was 152.3/85.5 mm Hg; 59.4% were women; 57.4% were Black, 33.2% were White, and 9.4% were Hispanic; 74% had hyperlipidemia; and 45.1% had type 2 diabetes. CC/SC did not improve BP control rates more than SCP. Both groups achieved statistically and clinically significant BP control rates at 12 months (CC/SC: 57.3% [95% CI, 52.7%-62.0%]; SCP: 56.7% [95% CI, 51.9%-61.5%]). Pairwise comparisons between racial and ethnic groups showed overall no significant differences in BP control at 12 months. Patients with coronary heart disease showed greater achievement of BP control in CC/SC than in SCP (64.0% [95% CI, 54.1%-73.9%] versus 50.8% [95% CI, 42.6%-59.0%]; P=0.04), as did patients in rural areas (67.3% [95% CI, 49.8%-84.8%] versus 47.8% [95% CI, 32.4%-63.2%]; P=0.01). Individuals in both arms experienced statistically and clinically significant reductions in mean systolic BP (CC/SC: -13.8 mm Hg [95% CI, -15.2 to -12.5]; SCP: -14.6 mm Hg [95% CI, -15.9 to -13.2]) and diastolic BP (CC/SC: -6.9 mm Hg [95% CI, -7.8 to -6.1]; SCP: -5.5 mm Hg [95% CI, -6.4 to -4.6]) over time. The difference in diastolic BP reduction between CC/SC and SCP over time was statistically significant (-1.4 mm Hg [95% CI, -2.6 to -0.2). Patient activation did not differ between arms. CC/SC showed greater improvements in patient ratings of chronic illness care (Patient Assessment of Chronic Illness Care score) over 12 months (0.12 [95% CI, 0.02-0.22]). CONCLUSIONS: Adding a collaborative care team to enhanced standard of care did not improve BP control but did improve patient ratings of chronic illness care.

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.

"Hang Ups, Let Downs, Bad Breaks, Setbacks": Impact of Structural Socioeconomic Racism and Resilience on Cognitive Change Over Time for Persons Racialized as Black.

Introduction: Older adults racialized as Black experience higher rates of dementia than those racialized as White. Structural racism produces socioeconomic challenges, described by artist Marvin Gaye as "hang ups, let downs, bad breaks, setbacks" that likely contribute to dementia disparities. Robust dementia literature suggests socioeconomic factors may also be key resiliencies. Methods: We linked state-level data reflecting the racialized landscape of economic opportunity across the 20th Century from the U.S. Census (1930-2010) with individual-level data on cognitive outcomes from the U.S. Health and Retirement Study participants racialized as Black. A purposive sample of participants born after the Brown v. Board ruling (born 1954-59) were selected who completed the modified Telephone Interview for Cognitive Status between 2010 and 2020 (N=1381). We tested associations of exposure to structural racism and resilience before birth, and during childhood, young-adulthood, and midlife with cognitive trajectories in mid-late life using mixed-effects regression models. Results: Older adults born in places with higher state-level structural socioeconomic racism experienced a more rapid cognitive decline in later life compared to those with lower levels of exposure. In addition, participants born in places with higher levels of state-level structural socioeconomic resilience experienced slower cognitive change over time than their counterparts. Discussion: These findings reveal the impact of racist U.S. policies enacted in the past that influence cognitive health over time and dementia risk later in life.

Place, Race, and Lapses in Diabetic Retinopathy Care.

This cohort study investigates the association of neighborhood-level social determinants of health with lapses in diabetic retinopathy care by race and ethnicity.

Association of Sevelamer Initiation with Gastrointestinal Bleeding Hospitalization in Individuals Requiring Hemodialysis.

Introduction Case reports have suggested a causative role between sevelamer use and subsequent gastrointestinal bleeding (GIB), but no large observational studies have evaluated this association. Methods Using the United States Renal Data System database from 2015 to 2019, we examined the association between initiation of sevelamer (versus non-sevelamer containing phosphate binders) and GIB hospitalization as well as all-cause mortality among individuals on hemodialysis. We emulated a target trial using Cox regression models and inverse probability of treatment weights to estimate the adjusted hazard ratios (HR) across outcomes and subgroups. Results Among 21,354 new users of phosphate binders (11,276 sevelamer and 10,078 non-sevelamer) with baseline lab data (calcium, phosphorus, hemoglobin, and albumin), there were 2,811 GIB hospitalizations and 5,920 deaths after a median follow-up of 1.3 years. Compared with the initiation of non-sevelamer binders, sevelamer was not associated with an increased risk of GIB hospitalization (89 vs. 90 events per 1000 person-years; IPTW-HR 0.98, 95% CI 0.91 - 1.06) or all-cause mortality (220 vs. 224 events per 1000 person-years; IPTW-HR 0.98 95% CI 0.93 - 1.03). Subgroup analyses (such as diabetes and anti-coagulation use) were generally consistent, and there was no association between sevelamer dose and GIB hospitalization. Conclusion Among patients requiring hemodialysis, sevelamer (vs non-sevelamer) containing phosphate binders was not associated with increased risk of GIB hospitalization.

Neighborhood-level social determinants of health and cardioprotective behaviors among church members in New Orleans, Louisiana.

BACKGROUND: Favorable neighborhood-level social determinants of health (SDoH) are associated with lower cardiovascular disease risk. Less is known about their influence on cardioprotective behaviors. We evaluated the associations between neighborhood-level SDoH and cardioprotective behaviors among church members in Louisiana. METHODS: Participants were surveyed between November 2021 to February 2022, and were asked about health behaviors, aspects of their neighborhood, and home address (to link to census tract and corresponding social deprivation index [SDI] data). Logistic regression models were used to assess the relation of neighborhood factors with the likelihood of engaging in cardioprotective behaviors: 1) a composite of healthy lifestyle behaviors [fruit and vegetable consumption, physical activity, and a tobacco/nicotine-free lifestyle], 2) medication adherence, and 3) receipt of routine medical care within the past year. RESULTS: Participants (n = 302, mean age: 63 years, 77% female, 99% Black) were recruited from 12 churches in New Orleans. After adjusting for demographic and clinical factors, perceived neighborhood walkability or conduciveness to exercise (odds ratio [OR]=1.25; 95% CI: 1.03, 1.53), availability of fruits and vegetables (OR=1.23; 95% CI: 1.07, 1.42), and social cohesion (OR=1.55; 95% CI: 1.22, 1.97) were positively associated with the composite of healthy lifestyle behaviors. After multivariable adjustment, SDI was in the direction of association with all three cardioprotective behavior outcomes, but associations were not statistically significant. CONCLUSIONS: In this predominantly Black, church-based population, neighborhood-level SDoH including the availability of fruits and vegetables, walkability or conduciveness to exercise, and social cohesion were associated with cardioprotective behaviors. Findings reiterate the need to address adverse neighborhood-level SDoH in the design and implementation of health interventions.

Similar Risk of Kidney Failure among Patients with Blinding Diseases Who Receive Ranibizumab, Aflibercept, and Bevacizumab: An Observational Health Data Sciences and Informatics Network Study.

PURPOSE: To characterize the incidence of kidney failure associated with intravitreal anti-VEGF exposure; and compare the risk of kidney failure in patients treated with ranibizumab, aflibercept, or bevacizumab. DESIGN: Retrospective cohort study across 12 databases in the Observational Health Data Sciences and Informatics (OHDSI) network. SUBJECTS: Subjects aged ≥ 18 years with ≥ 3 monthly intravitreal anti-VEGF medications for a blinding disease (diabetic retinopathy, diabetic macular edema, exudative age-related macular degeneration, or retinal vein occlusion). METHODS: The standardized incidence proportions and rates of kidney failure while on treatment with anti-VEGF were calculated. For each comparison (e.g., aflibercept versus ranibizumab), patients from each group were matched 1:1 using propensity scores. Cox proportional hazards models were used to estimate the risk of kidney failure while on treatment. A random effects meta-analysis was performed to combine each database's hazard ratio (HR) estimate into a single network-wide estimate. MAIN OUTCOME MEASURES: Incidence of kidney failure while on anti-VEGF treatment, and time from cohort entry to kidney failure. RESULTS: Of the 6.1 million patients with blinding diseases, 37 189 who received ranibizumab, 39 447 aflibercept, and 163 611 bevacizumab were included; the total treatment exposure time was 161 724 person-years. The average standardized incidence proportion of kidney failure was 678 per 100 000 persons (range, 0-2389), and incidence rate 742 per 100 000 person-years (range, 0-2661). The meta-analysis HR of kidney failure comparing aflibercept with ranibizumab was 1.01 (95% confidence interval [CI], 0.70-1.47; P = 0.45), ranibizumab with bevacizumab 0.95 (95% CI, 0.68-1.32; P = 0.62), and aflibercept with bevacizumab 0.95 (95% CI, 0.65-1.39; P = 0.60). CONCLUSIONS: There was no substantially different relative risk of kidney failure between those who received ranibizumab, bevacizumab, or aflibercept. Practicing ophthalmologists and nephrologists should be aware of the risk of kidney failure among patients receiving intravitreal anti-VEGF medications and that there is little empirical evidence to preferentially choose among the specific intravitreal anti-VEGF agents. FINANCIAL DISCLOSURES: Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Social Risk Groups in Patients With Diabetes With Differing Eye Care Utilization and Vision Outcomes.

Purpose: To evaluate whether latent class analysis on social determinants of health (SDoH) data can identify social risk groups that differ by adverse SDoH and vision outcomes in patients with diabetes. Methods: This was a prospective cohort study of adults ≥18 years with diabetes who completed a SDoH survey. Latent class analysis was used to cluster patients into social risk groups. The association of social risk group and severity of diabetic retinopathy, history of lapses in diabetic retinopathy care, and visual acuity was evaluated. Results: A total of 1006 participants were included. The three social risk groups differed by sociodemographic characteristics. The average age was 65, 60, and 54 in Groups 1, 2, and 3 respectively. Most (51%) patients in group 1 were non-Hispanic White, 66% in group 2 were non-Hispanic Black, and 80% in group 3 were Hispanic. Group 1 had the lowest burden of adverse SDoH per person (average 3.6), group 2 had 8.2, and group 3 had 10.5. In general, group 1 lacked diabetic retinopathy knowledge, group 2 had financial insecurity and difficulties with transportation, and group 3 had financial insecurity and did not have health insurance. Social risk group was associated with a history of lapses in diabetic retinopathy care, and presenting with worse vision. Conclusions and Translational Relevance: We identified distinct social risk groups among patients seeking care for diabetic retinopathy that differed by social needs, eye care utilization, and vision. Identifying these groups and their specific needs can help guide interventions to effectively address adverse SDoH and improve eye care utilization and vision outcomes among patients with diabetes.

Neighborhood Segregation and Access to Live Donor Kidney Transplantation.

Importance: Identifying the mechanisms of structural racism, such as racial and ethnic segregation, is a crucial first step in addressing the persistent disparities in access to live donor kidney transplantation (LDKT). Objective: To assess whether segregation at the candidate's residential neighborhood and transplant center neighborhood is associated with access to LDKT. Design, Setting, and Participants: In this cohort study spanning January 1995 to December 2021, participants included non-Hispanic Black or White adult candidates for first-time LDKT reported in the US national transplant registry. The median (IQR) follow-up time for each participant was 1.9 (0.6-3.0) years. Main Outcome and Measures: Segregation, measured using the Theil H method to calculate segregation tertiles in zip code tabulation areas based on the American Community Survey 5-year estimates, reflects the heterogeneity in neighborhood racial and ethnic composition. To quantify the likelihood of LDKT by neighborhood segregation, cause-specific hazard models were adjusted for individual-level and neighborhood-level factors and included an interaction between segregation tertiles and race. Results: Among 162 587 candidates for kidney transplant, the mean (SD) age was 51.6 (13.2) years, 65 141 (40.1%) were female, 80 023 (49.2%) were Black, and 82 564 (50.8%) were White. Among Black candidates, living in a high-segregation neighborhood was associated with 10% (adjusted hazard ratio [AHR], 0.90 [95% CI, 0.84-0.97]) lower access to LDKT relative to residence in low-segregation neighborhoods; no such association was observed among White candidates (P for interaction = .01). Both Black candidates (AHR, 0.94 [95% CI, 0.89-1.00]) and White candidates (AHR, 0.92 [95% CI, 0.88-0.97]) listed at transplant centers in high-segregation neighborhoods had lower access to LDKT relative to their counterparts listed at centers in low-segregation neighborhoods (P for interaction = .64). Within high-segregation transplant center neighborhoods, candidates listed at predominantly minority neighborhoods had 17% lower access to LDKT relative to candidates listed at predominantly White neighborhoods (AHR, 0.83 [95% CI, 0.75-0.92]). Black candidates residing in or listed at transplant centers in predominantly minority neighborhoods had significantly lower likelihood of LDKT relative to White candidates residing in or listed at transplant centers located in predominantly White neighborhoods (65% and 64%, respectively). Conclusions: Segregated residential and transplant center neighborhoods likely serve as a mechanism of structural racism, contributing to persistent racial disparities in access to LDKT. To promote equitable access, studies should assess targeted interventions (eg, community outreach clinics) to improve support for potential candidates and donors and ultimately mitigate the effects of segregation.

Patients' Perspectives on Health-Related Social Needs and Recommendations for Interventions: A Qualitative Study.

RATIONALE & OBJECTIVE: People with low socioeconomic status are disproportionately affected by kidney failure, and their adverse outcomes may stem from unmet health-related social needs. This study explored hemodialysis patient perspectives on health-related social needs and recommendations for intervention. STUDY DESIGN: Qualitative study using semistructured interviews. SETTINGS & PARTICIPANTS: Thirty-two people with low socioeconomic status receiving hemodialysis at 3 hemodialysis facilities in Austin, Texas. ANALYTICAL APPROACH: Interviews were analyzed for themes and subthemes using the constant comparative method. RESULTS: Seven themes and 21 subthemes (in parentheses) were identified: (1) kidney failure was unexpected (never thought it would happen to me; do not understand dialysis); (2) providers fail patients (doctors did not act; doctors do not care); (3) dialysis is detrimental (life is not the same; dialysis is all you do; dialysis causes emotional distress; dialysis makes you feel sick); (4) powerlessness (dependent on others; cannot do anything about my situation); (5) financial resource strain (dialysis makes you poor and keeps you poor; disability checks are not enough; food programs exist but are inconsistent; eat whatever food is available; not enough affordable housing; unstable housing affects health and well-being); (6) motivation to keep going (faith, support system, will to live); and (7) interventions should promote self-efficacy (navigation of community resources, support groups). LIMITATIONS: Limited quantitative data such as on dialysis vintage, and limited geographic representation. CONCLUSIONS: Dialysis exacerbates financial resource strain, and health-related social needs exacerbate dialysis-related stress. The participants made recommendations to address social needs with an emphasis on increasing support and community resources for this population. PLAIN-LANGUAGE SUMMARY: People receiving dialysis often experience health-related social needs, such as food and housing needs, but little is known about how these impact patients' health and well-being or how to best address them. We interviewed people receiving dialysis about how health-related social needs affect them and what they think dialysis facilities can do to help them address those needs. The participants reported that they often lose their independence after starting dialysis and health-related social needs are common, exacerbate their stress and emotional distress, and reduce their sense of well-being. Dialysis facilities may be able to enhance the experience of these patients by facilitating connections with local resources and providing opportunities for patients to support one another.

Association of Postoperative Delirium With Incident Dementia and Graft Outcomes Among Kidney Transplant Recipients.

BACKGROUND: Kidney transplant (KT) recipients have numerous risk factors for delirium, including those shared with the general surgical population (eg, age and major surgery) and transplant-specific factors (eg, neurotoxic immunosuppression medications). Evidence has linked delirium to long-term dementia risk in older adults undergoing major surgery. We sought to characterize dementia risk associated with post-KT delirium. METHODS: Using the United States Renal Data System datasets, we identified 35 800 adult first-time KT recipients ≥55 y. We evaluated risk factors for delirium using logistic regression. We evaluated the association between delirium and incident dementia (overall and by subtype: Alzheimer's, vascular, and other/mixed-type), graft loss, and death using Fine and Gray's subhazards models and Cox regression. RESULTS: During the KT hospitalization, 0.9% of recipients were diagnosed with delirium. Delirium risk factors included age (OR = 1.40, 95% CI, 1.28-1.52) and diabetes (OR = 1.38, 95% CI, 1.10-1.73). Delirium was associated with higher risk of death-censored graft loss (aHR = 1.52, 95% CI, 1.12-2.05) and all-cause mortality (aHR = 1.53, 95% CI, 1.25-1.89) at 5 y post-KT. Delirium was also associated with higher risk of dementia (adjusted subhazard ratio [aSHR] = 4.59, 95% CI, 3.48-6.06), particularly vascular dementia (aSHR = 2.51, 95% CI, 1.01-6.25) and other/mixed-type dementia (aSHR = 5.58, 95% CI, 4.24-7.62) subtypes. The risk of all-type dementia associated with delirium was higher for younger recipients aged between 55 and 64 y ( Pinteraction = 0.01). CONCLUSIONS: Delirium is a strong risk factor for subsequent diagnosis of dementia among KT recipients, particularly those aged between 55 and 64 y at the time of transplant. Patients experiencing posttransplant delirium might benefit from early interventions to enhance cognitive health and surveillance for cognitive impairment to enable early referral for dementia care.

Age Disparities in Access to First and Repeat Kidney Transplantation.

BACKGROUND: Evidence suggests that older patients are less frequently placed on the waiting list for kidney transplantation (KT) than their younger counterparts. The trends and magnitude of this age disparity in access to first KT and repeat KT (re-KT) remain unclear. METHODS: Using the US Renal Data System, we identified 2 496 743 adult transplant-naive dialysis patients and 110 338 adult recipients with graft failure between 1995 and 2018. We characterized the secular trends of age disparities and used Cox proportional hazard models to compare the chances of listing and receiving first KT versus re-KT by age (18-64 y versus ≥65 y). RESULTS: Older transplant-naive dialysis patients were less likely to be listed (adjusted hazard ratio [aHR] = 0.18; 95% confidence interval [CI], 0.17-0.18) and receive first KT (aHR = 0.88; 95% CI, 0.87-0.89) compared with their younger counterparts. Additionally, older patients with graft failure had a lower chance of being listed (aHR = 0.40; 95% CI, 0.38-0.41) and receiving re-KT (aHR = 0.76; 95% CI, 0.72-0.81). The magnitude of the age disparity in being listed for first KT was greater than that for re-KT ( Pinteraction < 0.001), and there were no differences in the age disparities in receiving first KT or re-KT ( Pinteraction = 0.13). Between 1995 and 2018, the age disparity in listing for first KT reduced significantly ( P < 0.001), but the age disparities in re-KT remained the same ( P = 0.16). CONCLUSIONS: Age disparities exist in access to both first KT and re-KT; however, some of this disparity is attenuated among older adults with graft failure. As the proportion of older patients with graft failure rises, a better understanding of factors that preclude their candidacy and identification of appropriate older patients are needed.

Factors Associated With Non-vaccination for Influenza Among Patients With CKD: Findings From the Chronic Renal Insufficiency Cohort (CRIC) Study.

RATIONALE & OBJECTIVE: Vaccination for influenza is strongly recommended for people with chronic kidney disease (CKD) due to their immunocompromised state. Identifying risk factors for not receiving an influenza vaccine (non-vaccination) could inform strategies for improving vaccine uptake in this high-risk population. STUDY DESIGN: Longitudinal observational study. SETTING & PARTICIPANTS: 3,692 Chronic Renal Insufficiency Cohort Study (CRIC) participants. EXPOSURE: Demographic factors, social determinants of health, clinical conditions, and health behaviors. OUTCOME: Influenza non-vaccination, which was assessed based on a receipt of influenza vaccine ascertained during annual clinic visits in a subset of participants who were under nephrology care. ANALYTICAL APPROACH: Mixed-effects Poisson models to estimate adjusted prevalence ratios (APRs). RESULTS: Between 2009 and 2020, the pooled mean vaccine uptake was 72% (mean age, 66 years; 44% female; 44% Black race). In multivariable models, factors significantly associated with influenza non-vaccination were younger age (APR, 2.16 [95% CI, 1.85-2.52] for<50 vs≥75 years), Black race (APR, 1.58 [95% CI, 1.43-1.75] vs White race), lower education (APR, 1.20 [95% CI, 1.04-1.39 for less than high school vs college graduate]), lower annual household income (APR, 1.26 [95% CI, 1.06-1.49] for <$20,000 vs >$100,000), formerly married status (APR, 1.22 [95% CI, 1.09-1.35] vs currently married), and nonemployed status (APR, 1.13 [95% CI, 1.02-1.24] vs employed). In contrast, participants with diabetes (APR, 0.80 [95% CI, 0.73-0.87] vs no diabetes), chronic obstructive pulmonary disease (COPD) (APR, 0.80 [95% CI, 0.70-0.92] vs no COPD), end-stage kidney disease (APR, 0.64 [0.56 to 0.76] vs estimated glomerular filtration rate≥60mL/min/1.73m2), frailty (APR, 0.86 [95% CI, 0.74-0.99] vs no frailty), and ideal physical activity (APR, 0.90 [95% CI, 0.82-0.99] vs. physically inactive) were less likely to have non-vaccination status. LIMITATIONS: Possible residual confounding. CONCLUSIONS: Among adults with CKD receiving nephrology care, younger adults, Black individuals, and those with adverse social determinants of health were more likely to have the influenza non-vaccination status. Strategies are needed to address these disparities and reduce barriers to vaccination. PLAIN-LANGUAGE SUMMARY: Identifying risk factors for not receiving an influenza vaccine ("non-vaccination") in people living with kidney disease, who are at risk of influenza and its complications, could inform strategies for improving vaccine uptake. In this study, we examined whether demographic factors, social determinants of health, and clinical conditions were linked to the status of not receiving an influenza vaccine among people living with kidney disease and receiving nephrology care. We found that younger adults, Black individuals, and those with adverse social determinants of health were more likely to not receive the influenza vaccine. These findings suggest the need for strategies to address these disparities and reduce barriers to vaccination in people living with kidney disease.

Modification of Association of Cystatin C With Kidney and Cardiovascular Outcomes by Obesity.

RATIONALE & OBJECTIVE: Cystatin C-based estimated glomerular filtration rate (eGFRcys) has stronger associations with adverse clinical outcomes than creatinine-based eGFR (eGFRcr). Obesity may be associated with higher cystatin C levels, independent of kidney function, but it is unknown whether obesity modifies associations of eGFRcys with kidney and cardiovascular outcomes. STUDY DESIGN: Cohort study. SETTING & PARTICIPANTS: 27,249 US adults in the Reasons for Geographic and Racial Differences in Stroke Study. PREDICTORS: eGFRcys, eGFRcr, waist circumference, and body mass index (BMI). OUTCOME: All-cause mortality, kidney failure, incident atherosclerotic cardiovascular disease (ASCVD), and incident heart failure (HF). ANALYTICAL APPROACH: Multivariable Cox and Fine-Gray models with multiplicative interaction terms were constructed to investigate whether waist circumference quartiles or BMI categories modified associations of eGFRcys with risks of 4 clinical outcomes. RESULTS: Participants had a mean age of 65 years; 54% were women, 41% were Black, and 21% had an eGFRcys<60mL/min/1.73m2. The baseline prevalence of abdominal obesity (waist circumference≥88cm for women or≥102cm for men) was 48% and obesity was 38%. In multivariable adjusted analyses, each 15mL/min/1.73m2 lower eGFRcys was associated with higher HR and 95% CI of mortality in each waist circumference quartile (first quartile, 1.19 [1.15-1.24]; second quartile, 1.22 [1.18-1.26]; third quartile, 1.20 [1.16-1.24]; fourth quartile, 1.19 [1.15-1.23]) as well as within each BMI category (BMI<24.9: 1.21 [1.17-1.25]; BMI 25.0-29.9: 1.21 [1.18-1.25]; BMI 30.0-34.9: 1.20 [1.16-1.25]; BMI≥35: 1.17, [1.12-1.22]). Neither waist circumference nor BMI modified the association of eGFRcys with mortality, kidney failure, incident ASCVD, or incident HF (all Pinteraction>0.05). LIMITATIONS: Included only Black and White persons in the United States. CONCLUSION: Obesity did not modify the association of eGFRcys with all-cause mortality, kidney failure, incident ASCVD, or incident HF. Among individuals with obesity, cystatin C may be used to provide eGFR-based risk prognostication for adverse outcomes. PLAIN-LANGUAGE SUMMARY: Cystatin C is increasingly used in clinical practice to estimate kidney function, and cystatin C-based eGFR (eGFRcys) may be used to determine risk for adverse clinical outcomes. Adiposity may increase serum levels of cystatin C, independent of kidney function. This cohort study investigated whether associations of eGFRcys with adverse kidney and cardiovascular outcomes are modified by measures of obesity, waist circumference, and body mass index. We found that obesity does not modify associations of eGFRcys with 4 clinical outcomes and conclude that among individuals with obesity, cystatin C may be used to provide eGFR-based risk prognostication for adverse outcomes.