Association of Medicaid Expansion With 1-Year Mortality Among Patients With End-Stage Renal Disease

Abstract

IMPORTANCE The Affordable Care Act Medicaid expansion may be associated with reduced mortality, but evidence to date is limited. Patients with end-stage renal disease (ESRD) are a high-risk group that may be particularly affected by Medicaid expansion. OBJECTIVE To examine the association of Medicaid expansion with 1-year mortality among nonelderly patients with ESRD initiating dialysis. DESIGN, SETTING, AND PARTICIPANTS Difference-in-differences analysis of nonelderly patients initiating dialysis in Medicaid expansion and nonexpansion states from January 2011 to March 2017. EXPOSURE Living in a Medicaid expansion state. MAIN OUTCOMES AND MEASURES The primary outcome was 1-year mortality. Secondary outcomes were insurance, predialysis nephrology care, and type of vascular access for hemodialysis. RESULTS A total of 142 724 patients in expansion states (mean age, 50.2 years; 40.2% women) and 93 522 patients in nonexpansion states (mean age, 49.7; 42.4% women) were included. In Medicaid expansion states, 1-year mortality following dialysis initiation declined from 6.9% in the preexpansion period to 6.1% after expansion (change, −0.8 percentage points; 95% CI, −1.1 to −0.5). In nonexpansion states, mortality rates were 7.0% before expansion and 6.8% after expansion (change, −0.2 percentage points; 95% CI, −0.5 to 0.2), yielding an adjusted absolute reduction in mortality in expansion states of −0.6 percentage points (95% CI, −1.0 to −0.2). Mortality reductions were largest for black patients (−1.4 percentage points; 95% CI, −2.2, −0.7; P=.04 for interaction) and patients aged 19 to 44 years (−1.1 percentage points; 95% CI, −2.1 to −0.3; P=.01 for interaction). Expansion was associated with a 10.5-percentage-point (95% CI, 7.7–13.2) increase in Medicaid coverage at dialysis initiation, a −4.2-percentage-point (95% CI, −6.0 to −2.3) decrease in being uninsured, and a 2.3-percentage-point (95% CI, 0.6–4.1) increase in the presence of an arteriovenous fistula or graft. Changes in predialysis nephrology care were not significant. CONCLUSIONS AND RELEVANCE Among patients with ESRD initiating dialysis, living in a state that expanded Medicaid under the Affordable Care Act was associated with lower 1-year mortality. If this association is causal, further research is needed to understand what factors may have contributed to this finding.

Association of Medicaid Expansion With Cardiovascular Mortality

“…Such early changes in outcomes have also been also reported in other analyses of expansion in insurance coverage. 5,7 However, these prior analyses were either focused on a single state (Massachusetts) or a specific chronic disease population (end-stage renal disease). The only randomized clinical trial of Medicaid expansion to date (the Oregon Health Study 6 ) did not demonstrate significant improve- ments in cardiovascular risk factors, such as hypertension or hyperlipidemia.…”

“…6 In a recent analysis of patients with end-stage renal disease, Medicaid expansion was associated with lower allcause mortality. 7 Cardiovascular disease and its risk factors disproportionately affect individuals of lower socioeconomic status and those who are uninsured. 8,9 Since Medicaid expansion has been associated with improvements in the management of diabetes, 10 increased use of cardioprotective medications, 11 and access to preventive care, 12 expansion in health insurance coverage may have a potential association with cardiovascular disease and mortality.…”

Trends in Mortality Among Patients Initiating Maintenance Dialysis in Puerto Rico Compared to US States, 2006-2015

“…Secondary outcomes were insurance status at dialysis initiation, the presence of AV fistula or graft at initiation (limited to hemodialysis patients), and receipt of predialysis nephrology care. 1,7 Covariates included age, sex, primary cause of kidney failure (diabetes, hypertension, and other), comorbid conditions, current smoking, alcohol dependence, hemoglobin level, serum albumin level, body mass index, and year. We used multiple imputation for missing data; <12% of values were missing for covariates except for albumin level (29%).…”

The Affordable Care Act's Effects on Patients, Providers, and the Economy: What We've Learned So Far

“…Another angle to examining mortality is to measure changes among more targeted populations gaining coverage. Two published studies have found significant mortality reductions due to the ACA-one examining the Medicaid expansion's effects among high risk patients starting dialysis (Swaminathan et al, 2018), and the other finding reduced disease-related mortality among young adults gaining coverage under the dependent coverage provision (McClellan, 2017). This is an impressive literature, but holes remain.…”