Border Health: State-Level Variation in Predialysis Nephrology Care.

For over four decades, Americans have enjoyed near universal access to treatment for ESRD irrespective of age, lack of qualifying disability, or their ability to pay. However, the health insurance benefits of the Medicare ESRD program do not extend to individuals in earlier stages of CKD, even to those for whom ESRD is imminent. Timely nephrology care before ESRD onset (predialysis nephrology care) has been linked not only to fewer biochemical abnormalities and increased use of an arteriovenous fistula or graft as initial vascular access, but more importantly, higher rates of kidney transplantation and lower rates of hospitalization and death compared with its absence (1–4). However, for many Americans, access to timely nephrology care remains elusive, particularly for members of vulnerable or traditionally underserved groups, such as racial-ethnic minorities, persons of severely limited socioeconomic means, and thosewho lack or churn in and out of health insurance coverage (1–3,5). Over one half of patients initiating ESRD treatment every year are estimated to belong to at least one of these underserved groups (6). On March 23, 2010, President Barack Obama signed into law the Patient Protection and Affordable Care Act (ACA), which was enacted to increase the availability, quality, and affordability of health insurance by expanding public and private insurance coverage. Key features of the ACA include Medicaid expansion to households with incomes up to 138% of the federal poverty level, and subsidized private coverage from insurance marketplaces for households with incomes between 100% and 400% of the federal poverty level (Medicaid currently covers 70 million people in the United States at an average annual cost of $475 billion) (7). In June of 2012, the US Supreme Court upheld the constitutionality of the ACA’s individual insurance mandate while also ruling to allow states to opt out of Medicaid expansion. Before the first enrollment phase of the ACA, the nation’s 43 million uninsured nonelderly residents were equally divided between the 31 states that have (to date) adopted the expansion and the 20 states that have not (8). In this issue of the Clinical Journal of the American Society ofNephrology (CJASN), Yan et al. (9) analyze registry data from the US Renal Data System to examine determinants of state to state variation in receipt of predialysis nephrology care (defined as nephrology care for 12 or more months before ESRD onset) among 373,986 adults who initiated ESRD treatment in the United States during 2005–2009. Leveraging patient-level data from the Centers of Medicare and Medicaid 2005 Medical Evidence Form (Form 2728-U3) on the presence and duration of nephrology care before ESRD treatment, Yan et al. (9) observed large interstate variation (10th–90th percentiles, 19%–42%) in receipt of predialysis nephrology care. Approximately one half to two thirds of this variation was attributable to state-level differences in general health care access, delivery of preventative care, and proxies of socioeconomic status. Among these indices, measures of general health care access, primarily the state’s fraction of uninsured nonelderly adults and the scope and performance of its Medicaid program, accounted for roughly one third of the total interstate variation. The findings by Yan et al. (9) align with and extend the observations of prior reports, which have linked predialysis nephrology care with area-based proxies of health insurance penetration, socioeconomic status, and racial-ethnic composition (10–13). Moreover, this study reinforces earlier observations by KurellaTamura et al. (12) that states with broader Medicaid coverage had smaller insurance–related gaps in predialysis nephrology care access and lower incidence of ESRD. In a large national survey of American adults, Sommers et al. (14) recently observed significant improvements in trends for self-reported coverage, access to a personal physician and medications, and health after the ACA’s first and second open enrollment periods. Combined with the study by Yan et al. (9), these reports generate considerable optimism for timely improvements in nephrology care access for patients with advanced CKD, most importantly for those who reside in states that bear a disproportionate burden of ESRD but where relatively low levels of predialysis nephrology care were observed (e.g., California, Illinois, and Pennsylvania). However, state-level delays in health insurance expansion are clearly bad news for many patients with progressive CKD and may further disadvantage vulnerable groups residing primarily in the South, where ESRD incidence is relatively high and access to predialysis nephrology care low compared with other regions of the nation. The study byYan et al. (9) also highlights deficiencies in the surveillance of health care provided to nonelderly adults with CKD in the United States. On the basis of their results, approximately 70% of adults initiating Kidney Research Institute, University of Washington, Seattle, Washington