Disparities in Chronic Kidney Disease Progression by Medicare Advantage Enrollees.

INTRODUCTION: The prevalence of chronic kidney disease (CKD) in Medicare beneficiaries has quadrupled in the past 2 decades, but little is known about risk factors affecting the progression of CKD. This study aims to understand the progression in Medicare Advantage enrollees and whether it differs by provider recognition of CKD, race and ethnicity, or geographic location. In a large cohort of Medicare Advantage (MA) enrollees, we examined whether CKD progression, up to 5 years after study entry, differed by demographic and clinical factors and identified additional risk factors of CKD progression. METHODS: In a cohort of 1,002,388 MA enrollees with CKD stages 1-4 based on 2013-2018 labs, progression was estimated using a mixed-effects model that adjusted for demographics, geographic location, comorbidity, urine albumin-to-creatinine ratio, clinical recognition via diagnosed CKD, and time-fixed effects. Race and ethnicity, geographic location, and clinical recognition of CKD were interacted with time in 3 separate regression models. RESULTS: Mean (median) follow-up was 3.1 (3.0) years. Black and Hispanic MA enrollees had greater kidney function at study entry than other beneficiaries, but their kidney function declined faster. MA enrollees with clinically recognized CKD had estimated glomerular filtration rate levels that were 18.6 units (95% confidence interval [CI]: 18.5-18.7) lower than levels of unrecognized patients, but kidney function declined more slowly in enrollees with clinical recognition. There were no differences in CKD progression by geography. After removal of the race coefficient from the eGFR equation in a sensitivity analysis, kidney function was much lower in all years among Black MA enrollees, but patterns of progression remained the same. DISCUSSION/CONCLUSIONS: These results suggest that patients with clinically recognized CKD and racial and ethnic minorities merit closer surveillance and management to reduce their risk of faster progression.

Life Course Socioeconomic Status, Allostatic Load, and Kidney Health in Black Americans.

BACKGROUND AND OBJECTIVES: Low socioeconomic status confers unfavorable health, but the degree and mechanisms by which life course socioeconomic status affects kidney health is unclear. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: We examined the association between cumulative lifetime socioeconomic status and CKD in black Americans in the Jackson Heart Study. We used conditional process analysis to evaluate allostatic load as a potential mediator of this relation. Cumulative lifetime socioeconomic status was an age-standardized z-score, which has 1-SD units by definition, and derived from self-reported childhood socioeconomic status, education, and income at baseline. Allostatic load encompassed 11 baseline biomarkers subsuming neuroendocrine, metabolic, autonomic, and immune physiologic systems. CKD outcomes included prevalent CKD at baseline and eGFR decline and incident CKD over follow-up. RESULTS: Among 3421 participants at baseline (mean age 55 years [SD 13]; 63% female), cumulative lifetime socioeconomic status ranged from -3.3 to 2.3, and 673 (20%) had prevalent CKD. After multivariable adjustment, lower cumulative lifetime socioeconomic status was associated with greater prevalence of CKD both directly (odds ratio [OR], 1.18; 95% confidence interval [95% CI], 1.04 to 1.33 per 1 SD and OR, 1.45; 95% CI, 1.15 to 1.83 in lowest versus highest tertile) and via higher allostatic load (OR, 1.09; 95% CI, 1.06 to 1.12 per 1 SD and OR, 1.17; 95% CI, 1.11 to 1.24 in lowest versus highest tertile). After a median follow-up of 8 years (interquartile range, 7-8 years), mean annual eGFR decline was 1 ml/min per 1.73 m2 (SD 2), and 254 out of 2043 (12%) participants developed incident CKD. Lower cumulative lifetime socioeconomic status was only indirectly associated with greater CKD incidence (OR, 1.04; 95% CI, 1.01 to 1.07 per 1 SD and OR, 1.08; 95% CI, 1.02 to 1.14 in lowest versus highest tertile) and modestly faster annual eGFR decline, in milliliters per minute (OR, 0.01; 95% CI, 0.00 to 0.02 per 1 SD and OR, 0.02; 95% CI, 0.00 to 0.04 in lowest versus highest tertile), via higher baseline allostatic load. CONCLUSIONS: Lower cumulative lifetime socioeconomic status was substantially associated with CKD prevalence but modestly with CKD incidence and eGFR decline via baseline allostatic load.

Primary care-specialist collaboration in the care of patients with chronic kidney disease.

BACKGROUND AND OBJECTIVES: Collaboration between primary care physicians (PCPs) and nephrologists in the care of patients with chronic kidney disease (CKD) is widely advocated, but physician preferences regarding collaboration are unknown. Physicians' desires to collaborate in the care of a hypothetical patient with CKD, their preferred content of collaboration, and their perceived barriers to collaboration were assessed. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: A questionnaire describing the care of a hypothetical patient with progressive CKD was administered to a national sample of U.S. PCPs and nephrologists. Physician characteristics and attitudes associated with desires to collaborate were identified. RESULTS: Among 124 PCPs and 120 nephrologists, most physicians (85% PCPs versus 94% nephrologists) desired collaboration. Nephrologists were more likely than PCPs to prefer collaboration focus on predialysis/renal replacement therapy preparation and electrolyte management (73% versus 52% and 81% versus 46%, respectively). PCPs were more likely to desire collaboration if the hypothetical patient had diabetes and hypertension (versus hypertension alone), if they believed the care they provide helps slow CKD disease progression, and if they did not perceive health insurance as a barrier to nephrology referral (adjusted percentages [95% confidence interval]: 94% [80 to 98] versus 75% [reference]), 92% [75 to 98] versus 75% [reference], 42% [9 to 85] versus 88% [reference], respectively). CONCLUSIONS: Most PCPs and nephrologists favored collaborative care for a patient with progressive CKD, but their preferred content of collaboration differed. Collaborative models that explicitly include PCPs in the care of patients with CKD may help improve patients' clinical outcomes.