The Protective Role of Medicaid Expansion for Low-Income People During the COVID-19 Pandemic

IF 3.2 2区 医学 Q2 HEALTH CARE SCIENCES & SERVICES Health Services Research Pub Date : 2025-02-01 DOI:10.1111/1475-6773.14444
Aparna Soni, Kevin N. Griffith
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While health and income losses during the pandemic were widespread, a growing body of literature demonstrates that residents of Medicaid expansion states suffered less than their non-expansion peers. Thus, Medicaid may provide important protective benefits and increase the resiliency of our health system.</p><p>This commentary synthesizes the growing literature that examines the impacts of Medicaid expansion on low-income individuals during the pandemic. Many studies have found that state investments in public health, particularly through Medicaid expansion, helped protect low-income individuals from some of the negative impacts of the COVID-19 pandemic. We begin by describing the landscape of Medicaid policy at the onset of the pandemic. We then provide a synopsis of the emerging body of literature that studies the effects of Medicaid expansion during the pandemic. We conclude by discussing challenges and opportunities for Medicaid expansion as a vehicle to protect low-income people during future public health emergencies.</p><p>President Donald J. Trump declared the COVID-19 pandemic a nationwide emergency on March 13th, 2020 [<span>5</span>]. By this date, 35 states and the District of Columbia had expanded Medicaid under the ACA [<span>6</span>]. A voluminous literature generally demonstrates that, compared to non-expanders, residents of Medicaid expansion states experienced better access to care [<span>7-9</span>] and improved health outcomes [<span>10-13</span>] during the pre-pandemic period and that these benefits disproportionately accrued to low-income or minoritized populations [<span>14-16</span>].</p><p>When the pandemic struck, the Medicaid program stood ready to fill an essential role protecting low-income individuals and essential workers, who were most susceptible to the pandemic's adverse effects. Expansion states were better positioned to take advantage of federal policy changes that were implemented to strengthen Medicaid, such as the Families First Coronavirus Response Act of 2020 (FFCRA). As part of the FFCRA, all state Medicaid programs adopted maintenance of eligibility and continuous coverage provisions that essentially prohibited states from terminating most enrollees' coverage until after the end of the public health emergency. However, these provisions were expected to increase mandatory spending during an especially challenging time for state budgets due to declining income and sales tax revenues. The FFCRA provided states with an additional 6.2 percentage point increase in federal matching assistance percentage (FMAP) to offset these costs (from a baseline FMAP range of 56.20% to 83.18% across states).</p><p>The continuous coverage provision was associated with unprecedented increases in Medicaid enrollment, reducing churn and access disruptions among enrollees. Between February 2020 and January 2023, enrollment increased more than 30% or 21 million people nationwide [<span>17</span>]. As we describe below, residents of Medicaid expansion states benefitted most from the FFCRA during the pandemic.</p><p>A surge of new research is shedding light on the crucial role Medicaid expansions under the ACA had during the COVID-19 pandemic, especially for low-income Americans. Studies using quasi-experimental research designs show that compared to non-expansion states, Medicaid expansions improved access to care and boosted health outcomes for low-income populations. The key results of 11 such studies are summarized in Table 1. We restricted our focus to studies that examined the effects of state Medicaid expansions during the pandemic and employed rigorous quasi-experimental designs. Most of these studies applied either regression discontinuity or difference-in-differences approaches to compare outcomes in states that did and did not expand Medicaid, before and after the onset of the COVID-19 public health emergency. We excluded descriptive or cross-sectional studies from our summary.</p><p>The literature reviewed in this commentary underscores Medicaid expansion's critical role during the COVID-19 pandemic but has limitations. Unlike pre-pandemic studies, these analyses cannot leverage states' staggered Medicaid adoption decisions to control for potential confounding factors. Instead, this work relies on pre- and post-pandemic comparisons in expansion versus non-expansion states, making it harder to isolate the effects of Medicaid expansion from other correlated policies. Although most studies control for pandemic-related policies like mask mandates and stay-at-home orders, expansion states may have also implemented additional pre-pandemic safety net benefits. These could include more generous unemployment insurance, higher minimum wages, expanded housing assistance programs, or robust food assistance initiatives like Supplemental Nutrition Assistance Program (SNAP) enhancements. These correlated benefits complicate efforts to isolate the specific effects of Medicaid expansion during the pandemic. Additionally, the continuous coverage provision confounds analyses by making it challenging to disentangle the specific effects of Medicaid expansion from the broader impacts of this universal policy. Both may have contributed to increased access to care and financial stability for low-income populations during the pandemic, but their intertwined effects obscure a clear understanding of Medicaid expansion's unique role.</p><p>Additionally, most studies used data from 2020 to 2021 due to lags in availability, despite the public health emergency extending into 2023. Surveys collected early in the pandemic faced challenges like low response rates and potential non-response bias, although post-stratification weighting may ameliorate some of these issues. More research is needed to evaluate Medicaid expansion's role across the full pandemic, particularly for outcomes like COVID-19 morbidity, mortality, and prevention.</p><p>A growing literature, summarized above, suggests that Medicaid expansion was associated with increased insurance coverage, improved access to care, improved some health-related behaviors, and eased financial strain among low-income people during the COVID-19 pandemic. We observed during the pandemic that reliance on employer-sponsored insurance makes us less resilient during times of economic downturn. Nearly 14.6 million workers and their dependents lost employer-sponsored insurance coverage during the first four months of the COVID-19 public health emergency [<span>35</span>].</p><p>By ensuring the health and protection of low-income populations, Medicaid expansion can help offset losses during public health emergencies and economic downturns. However, a lack of public awareness may have diminished Medicaid's effectiveness. Survey evidence suggests that millions of enrollees were unaware their coverage was maintained during the pandemic and mistakenly self-identified as uninsured [<span>36</span>]. States may not have effectively communicated that individuals were automatically retained on Medicaid during the pandemic, and many beneficiaries misunderstood the continuous coverage provision or its impact on their eligibility. This “Medicaid undercount” weakens the program's ability to improve access, increase health services utilization, and enhance health outcomes [<span>37</span>].</p><p>Despite these benefits, the Medicaid program faces several challenges ahead. First, there has been a surge in disenrollment starting in 2023. Over 25 million people lost their Medicaid coverage since the end of the COVID-19 public health emergency, as states resume the pre-pandemic process of periodically redetermining eligibility for Medicaid [<span>38</span>]. A survey found that roughly half of those who lost Medicaid coverage became uninsured, and even those who moved to new insurance experienced coverage gaps and reported challenges accessing care [<span>39</span>].</p><p>Additionally, not all states expanded Medicaid to cover their low-income populations. Five states expanded during the pandemic including Nebraska, Oklahoma, Missouri, South Dakota, and North Carolina. 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引用次数: 0

Abstract

During the first year of the COVID-19 pandemic, nearly 47.5 million Americans lost their employer-sponsored health insurance. While many were able to transition to plans from other family members, 56% became uninsured [1]—a deleterious result during the height of a pandemic. Lower-income workers are most likely to be laid off and lose coverage during economic downturns, exacerbating socioeconomic disparities in healthcare access [2, 3]. Medicaid served as an essential lifeline for individuals and families during the pandemic, and enrollment rose steadily throughout 2020, especially in states that expanded Medicaid as part of the Affordable Care Act (ACA) [4]. While health and income losses during the pandemic were widespread, a growing body of literature demonstrates that residents of Medicaid expansion states suffered less than their non-expansion peers. Thus, Medicaid may provide important protective benefits and increase the resiliency of our health system.

This commentary synthesizes the growing literature that examines the impacts of Medicaid expansion on low-income individuals during the pandemic. Many studies have found that state investments in public health, particularly through Medicaid expansion, helped protect low-income individuals from some of the negative impacts of the COVID-19 pandemic. We begin by describing the landscape of Medicaid policy at the onset of the pandemic. We then provide a synopsis of the emerging body of literature that studies the effects of Medicaid expansion during the pandemic. We conclude by discussing challenges and opportunities for Medicaid expansion as a vehicle to protect low-income people during future public health emergencies.

President Donald J. Trump declared the COVID-19 pandemic a nationwide emergency on March 13th, 2020 [5]. By this date, 35 states and the District of Columbia had expanded Medicaid under the ACA [6]. A voluminous literature generally demonstrates that, compared to non-expanders, residents of Medicaid expansion states experienced better access to care [7-9] and improved health outcomes [10-13] during the pre-pandemic period and that these benefits disproportionately accrued to low-income or minoritized populations [14-16].

When the pandemic struck, the Medicaid program stood ready to fill an essential role protecting low-income individuals and essential workers, who were most susceptible to the pandemic's adverse effects. Expansion states were better positioned to take advantage of federal policy changes that were implemented to strengthen Medicaid, such as the Families First Coronavirus Response Act of 2020 (FFCRA). As part of the FFCRA, all state Medicaid programs adopted maintenance of eligibility and continuous coverage provisions that essentially prohibited states from terminating most enrollees' coverage until after the end of the public health emergency. However, these provisions were expected to increase mandatory spending during an especially challenging time for state budgets due to declining income and sales tax revenues. The FFCRA provided states with an additional 6.2 percentage point increase in federal matching assistance percentage (FMAP) to offset these costs (from a baseline FMAP range of 56.20% to 83.18% across states).

The continuous coverage provision was associated with unprecedented increases in Medicaid enrollment, reducing churn and access disruptions among enrollees. Between February 2020 and January 2023, enrollment increased more than 30% or 21 million people nationwide [17]. As we describe below, residents of Medicaid expansion states benefitted most from the FFCRA during the pandemic.

A surge of new research is shedding light on the crucial role Medicaid expansions under the ACA had during the COVID-19 pandemic, especially for low-income Americans. Studies using quasi-experimental research designs show that compared to non-expansion states, Medicaid expansions improved access to care and boosted health outcomes for low-income populations. The key results of 11 such studies are summarized in Table 1. We restricted our focus to studies that examined the effects of state Medicaid expansions during the pandemic and employed rigorous quasi-experimental designs. Most of these studies applied either regression discontinuity or difference-in-differences approaches to compare outcomes in states that did and did not expand Medicaid, before and after the onset of the COVID-19 public health emergency. We excluded descriptive or cross-sectional studies from our summary.

The literature reviewed in this commentary underscores Medicaid expansion's critical role during the COVID-19 pandemic but has limitations. Unlike pre-pandemic studies, these analyses cannot leverage states' staggered Medicaid adoption decisions to control for potential confounding factors. Instead, this work relies on pre- and post-pandemic comparisons in expansion versus non-expansion states, making it harder to isolate the effects of Medicaid expansion from other correlated policies. Although most studies control for pandemic-related policies like mask mandates and stay-at-home orders, expansion states may have also implemented additional pre-pandemic safety net benefits. These could include more generous unemployment insurance, higher minimum wages, expanded housing assistance programs, or robust food assistance initiatives like Supplemental Nutrition Assistance Program (SNAP) enhancements. These correlated benefits complicate efforts to isolate the specific effects of Medicaid expansion during the pandemic. Additionally, the continuous coverage provision confounds analyses by making it challenging to disentangle the specific effects of Medicaid expansion from the broader impacts of this universal policy. Both may have contributed to increased access to care and financial stability for low-income populations during the pandemic, but their intertwined effects obscure a clear understanding of Medicaid expansion's unique role.

Additionally, most studies used data from 2020 to 2021 due to lags in availability, despite the public health emergency extending into 2023. Surveys collected early in the pandemic faced challenges like low response rates and potential non-response bias, although post-stratification weighting may ameliorate some of these issues. More research is needed to evaluate Medicaid expansion's role across the full pandemic, particularly for outcomes like COVID-19 morbidity, mortality, and prevention.

A growing literature, summarized above, suggests that Medicaid expansion was associated with increased insurance coverage, improved access to care, improved some health-related behaviors, and eased financial strain among low-income people during the COVID-19 pandemic. We observed during the pandemic that reliance on employer-sponsored insurance makes us less resilient during times of economic downturn. Nearly 14.6 million workers and their dependents lost employer-sponsored insurance coverage during the first four months of the COVID-19 public health emergency [35].

By ensuring the health and protection of low-income populations, Medicaid expansion can help offset losses during public health emergencies and economic downturns. However, a lack of public awareness may have diminished Medicaid's effectiveness. Survey evidence suggests that millions of enrollees were unaware their coverage was maintained during the pandemic and mistakenly self-identified as uninsured [36]. States may not have effectively communicated that individuals were automatically retained on Medicaid during the pandemic, and many beneficiaries misunderstood the continuous coverage provision or its impact on their eligibility. This “Medicaid undercount” weakens the program's ability to improve access, increase health services utilization, and enhance health outcomes [37].

Despite these benefits, the Medicaid program faces several challenges ahead. First, there has been a surge in disenrollment starting in 2023. Over 25 million people lost their Medicaid coverage since the end of the COVID-19 public health emergency, as states resume the pre-pandemic process of periodically redetermining eligibility for Medicaid [38]. A survey found that roughly half of those who lost Medicaid coverage became uninsured, and even those who moved to new insurance experienced coverage gaps and reported challenges accessing care [39].

Additionally, not all states expanded Medicaid to cover their low-income populations. Five states expanded during the pandemic including Nebraska, Oklahoma, Missouri, South Dakota, and North Carolina. The remaining 10 holdout states lack feasible options for expansion via executive order or ballot initiative; endorsement from their state legislatures is paramount. The next administration should support creative Section 1115 waivers that encourage the remaining non-expansion states to adopt Medicaid in ways that work for them. For instance, Arkansas received approval for a market-based approach, allowing Medicaid enrollees to buy private health plans through the state's individual insurance exchange. Providing states with similar flexibility and incentives could expand Medicaid in the remaining 10 states, benefiting low-income populations and strengthening our resilience in future public health emergencies and recessions.

Significant gaps in our understanding of Medicaid expansion's protective effects remain, and future research must address these to provide a clearer picture. Researchers need to disentangle the effects of Medicaid expansion from other public program benefits and the continuous coverage provision by leveraging detailed policy variation across states and over time. Comparative studies that incorporate granular data on state-level policy generosity and timing, as well as natural experiments or simulation models, could help isolate the distinct contributions of Medicaid expansion. Current studies relying on 2020 and 2021 data offer valuable insights into the immediate impacts during the pandemic, but longer term analyses are crucial as more recent data become available. These studies will be essential to fully understanding how Medicaid expansion's effects evolved, particularly as pandemic era policies like the continuous coverage provision phase out and states adapt their public programs.

The human cost of COVID-19 has been enormous, and the pandemic's economic fallout sharply reduced access to care as layoffs ended employer-sponsored health insurance. These pains were disproportionately experienced by low-income individuals and their families. A growing empirical literature suggests that enhanced access to Medicaid offset some of the negative financial and health impacts. Holdout states should view Medicaid expansion as a way to strengthen health system resilience, safeguard low-income populations, and reduce the risk of worsening socioeconomic disparities in future pandemics.

The authors declare no conflicts of interest.

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COVID-19大流行期间医疗补助扩大对低收入人群的保护作用。
在2019冠状病毒病大流行的第一年,近4750万美国人失去了雇主赞助的医疗保险。虽然许多人能够过渡到其他家庭成员的计划,但56%的人没有保险,这是在疫情最严重时期的有害结果。在经济衰退期间,低收入工人最有可能被解雇并失去保险,从而加剧了医疗保健获取方面的社会经济差距[2,3]。在疫情期间,医疗补助是个人和家庭的重要生命线,整个2020年,医疗补助的注册人数稳步上升,尤其是在那些将医疗补助扩大为《平价医疗法案》(ACA)一部分的州。虽然大流行期间的健康和收入损失很普遍,但越来越多的文献表明,扩大医疗补助计划的州的居民比没有扩大医疗补助计划的同龄人遭受的损失要小。因此,医疗补助可以提供重要的保护利益,并增加我们医疗系统的弹性。这篇评论综合了越来越多的文献,这些文献研究了大流行期间医疗补助扩张对低收入人群的影响。许多研究发现,国家对公共卫生的投资,特别是通过扩大医疗补助计划,有助于保护低收入人群免受COVID-19大流行的一些负面影响。我们先来描述一下大流行开始时的医疗补助政策。然后,我们提供了一个新出现的文献体的摘要,这些文献研究了大流行期间医疗补助扩张的影响。最后,我们讨论了在未来突发公共卫生事件中,扩大医疗补助作为保护低收入人群的工具所面临的挑战和机遇。唐纳德·j·特朗普总统于2020年3月13日宣布COVID-19大流行进入全国紧急状态。到目前为止,35个州和哥伦比亚特区已经根据ACA扩大了医疗补助计划。大量文献普遍表明,在大流行前,与未扩大医疗补助的州相比,扩大医疗补助的州的居民获得了更好的医疗服务[7-9],健康状况得到了改善[10-13],而这些好处不成比例地流向了低收入或少数群体[14-16]。当大流行来袭时,医疗补助计划准备好扮演一个重要的角色,保护低收入个人和基本工人,他们最容易受到大流行的不利影响。扩张州更有能力利用为加强医疗补助而实施的联邦政策变化,例如2020年《家庭第一冠状病毒应对法案》(FFCRA)。作为FFCRA的一部分,所有州的医疗补助计划都采用了维持资格和持续覆盖的条款,基本上禁止各州在公共卫生紧急情况结束之前终止大多数参保人的覆盖。然而,由于收入和销售税收入的下降,这些条款预计将在国家预算面临特别挑战的时期增加强制性支出。FFCRA向各州额外提供6.2个百分点的联邦匹配援助百分比(FMAP),以抵消这些成本(各州FMAP的基线范围为56.20%至83.18%)。持续覆盖的规定与医疗补助登记人数的空前增加有关,减少了参保人员的流失和访问中断。从2020年2月到2023年1月,全国招生人数增加了2100万人,增幅超过30%。正如我们下面所描述的,在大流行期间,医疗补助扩张州的居民从FFCRA中受益最多。大量新研究揭示了ACA下医疗补助扩张在COVID-19大流行期间的关键作用,特别是对低收入美国人来说。使用准实验研究设计的研究表明,与未扩大医疗补助的州相比,扩大医疗补助的州改善了获得医疗服务的机会,提高了低收入人群的健康状况。表1总结了11项此类研究的关键结果。我们将研究的重点限制在检查大流行期间州医疗补助扩张影响的研究上,并采用严格的准实验设计。这些研究中的大多数采用了回归不连续或差异中的差异方法来比较在COVID-19突发公共卫生事件发生之前和之后扩大医疗补助和未扩大医疗补助的州的结果。我们在总结中排除了描述性或横断面研究。本评论回顾的文献强调了医疗补助扩张在COVID-19大流行期间的关键作用,但也有局限性。与流行病前的研究不同,这些分析不能利用各州交错的医疗补助采用决定来控制潜在的混杂因素。 将州级政策慷慨度和时间安排的细粒度数据以及自然实验或模拟模型结合起来的比较研究,可以帮助分离出医疗补助扩张的不同贡献。目前基于2020年和2021年数据的研究为大流行期间的直接影响提供了有价值的见解,但随着更多最新数据的出现,长期分析至关重要。这些研究对于充分理解医疗补助扩张的影响是如何演变的至关重要,特别是在大流行时期,像持续覆盖提供这样的政策逐渐消失,各州调整他们的公共项目。COVID-19给人类造成了巨大的损失,随着裁员结束了雇主赞助的医疗保险,大流行的经济影响大大减少了获得医疗服务的机会。低收入个人及其家庭所承受的痛苦尤为严重。越来越多的实证文献表明,增加获得医疗补助的机会抵消了一些负面的财务和健康影响。坚持不懈的州应将扩大医疗补助计划视为加强卫生系统复原力、保护低收入人群和减少未来流行病中社会经济差距恶化风险的一种方式。作者声明无利益冲突。
本文章由计算机程序翻译,如有差异,请以英文原文为准。
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来源期刊
Health Services Research
Health Services Research 医学-卫生保健
CiteScore
4.80
自引率
5.90%
发文量
193
审稿时长
4-8 weeks
期刊介绍: Health Services Research (HSR) is a peer-reviewed scholarly journal that provides researchers and public and private policymakers with the latest research findings, methods, and concepts related to the financing, organization, delivery, evaluation, and outcomes of health services. Rated as one of the top journals in the fields of health policy and services and health care administration, HSR publishes outstanding articles reporting the findings of original investigations that expand knowledge and understanding of the wide-ranging field of health care and that will help to improve the health of individuals and communities.
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