Editorial <\/p>\n\n\n\n
December 27, 2022<\/p>\n\n\n\n
Researchers have been using statistical methods to investigate the link between health and income in both adults and children since individual-level data allowing them to do so first became available.1<\/a><\/sup>-3<\/a><\/sup> However, previous investigators were forced to rely on highly imperfect data. Sample sizes were often small, indicators for socioeconomic status were crude, and health status and the presence or absence of acute and chronic conditions was generally self (or parent) reported. Despite these limitations, evidence emerged of a robust relationship between income and health measures, including the presence of chronic conditions, activity limitations, and preventable hospitalizations.<\/a><\/p>\n\n\n\n In this issue of JAMA<\/em>, Udalova and colleagues provide an example of the exciting insights that can be achieved when new data are applied to old questions.4<\/a><\/sup> The remarkable data assembled for this study start with individual-level Medicaid or Children\u2019s Health Insurance Program (CHIP) public health insurance claims for children aged 5 to 17 years in 2011 and 2012. For each child in the claims data, family income was obtained by matching to US Census Bureau records. Given the reliance on public health insurance records, the data set was limited to children with family incomes less than 200% of the federal poverty threshold ($36 212 in 2011 and $43 622 in 2021 for a family of 3 individuals). Participants were followed up for up to 10 years to determine whether death was recorded in the Social Security Administration files. These procedures yielded a sample of 795\u202f000 children and adolescents with detailed information on their diagnosed health conditions and a follow-up that allowed the effects on mortality to be assessed.<\/a><\/p>\n\n\n\n The study found an inverse relationship between income and all analyzed health conditions, which was particularly strong for mental health disorders. The headline finding is that an additional $20\u202f000 in annual income was associated with a 15% reduction in the probability of mental health disorders for children aged 5 to 9 years. Injuries decreased by approximately 12% with the same change in income. Other conditions, including 10-year mortality and substance use disorders, decreased by 5% to 10%.<\/a><\/p>\n\n\n\n By limiting their sample to the lower part of the income distribution, the authors focused on a group for whom the relationship between income and health is expected to be especially strong. At the same time, because the participants were continuously enrolled in Medicaid or CHIP, they arguably had more similar access to care than would be the case in a sample that mixed publicly and privately insured children or included uninsured children. Hence, the differences in health outcomes between children and adolescents from higher- and lower-income families in these data might be muted if differences in health insurance access are also a main driver of the relationship between income and health.<\/a><\/p>\n\n\n\n In addition, the differences between the children from families with the lowest income and those in families with incomes outside the range of this study is likely even greater. This means that although the effects this study finds are large, they are likely to understate the full size of the disparity in health between higher- and lower-income children.<\/a><\/p>\n\n\n\n A second finding in the current study was that the relationship between health and income strengthens with age for most conditions, as previous studies have also found.5<\/a><\/sup> For instance, although mean mortality was twice as high for children aged 10 to 17 years compared with children aged 5 to 9 years in the current study, the slope of the relationship between income and mortality was 6 times greater for children aged 10 to 17 years old compared with children aged 5 to 9 years.<\/a><\/p>\n\n\n\n The finding that there was a significant relationship between income and health even among children with public health insurance is consistent with studies in many countries with universal public health insurance, such as Canada,6<\/a><\/sup> England, France, or Germany.7<\/a><\/sup> These studies also found a significant relationship between income and health that strengthened with age. The fact that all of the children in this study were continuously covered by Medicaid should not have been expected to eliminate income-related disparities in health.<\/a><\/p>\n\n\n\n A key question is whether Medicaid improves child health relative to what it would have been without Medicaid coverage. This question cannot be answered using a sample that consists entirely of individuals continuously enrolled in Medicaid. However, recent studies have shown that the introduction and expansion of Medicaid\u2019s public health insurance coverage for children was associated with improvements in child health, including reductions in poor self-reported health, chronic conditions, and hospitalizations.8<\/a><\/sup>,9<\/a><\/sup><\/a><\/p>\n\n\n\n For example, Currie and colleagues found that although the relationship between family income and child health still exists in the US, it became weaker after expansions of the Medicaid program among birth cohorts who gained coverage in early childhood.9<\/a><\/sup> Similarly, we found that both income-related and racial disparities in mortality declined between 1990 and 2018 among individuals aged 18 years and younger in the US even though overall income inequality was increasing.7<\/a><\/sup>,10<\/a><\/sup> These were the cohorts who benefitted from the expansions of public health insurance. Thus, previous evidence suggests that although it would be naive to think that expansions of health insurance coverage could eliminate disparities in health, it can help to mitigate them.<\/a><\/p>\n\n\n\n If the relationship between income and health is not due only to differential access to medical care, then what is the underlying cause? Although the current study cannot answer this question, it provides some clues. The authors show that lower-income children have more injuries and more infections, which is consistent with previous work showing that lower-income children have more health \u201cshocks\u201d than higher-income children.11<\/a><\/sup>,12<\/a><\/sup> Indeed, perhaps one of the defining characteristics of poverty is that families are less able to protect children from insults to their health.<\/a><\/p>\n\n\n\n Despite reductions in health disparities among US children during the 2 decades leading up to the COVID-19 pandemic, the relationship between health and income remains much stronger in the US than in peer countries. Moreover, even children in the highest-income US areas experience poorer health than children in comparable European areas.7<\/a><\/sup> These patterns suggest that US children experience unique health risks, and that these risks affect lower-income children in the US particularly strongly. In comparison with France, for example, mortality rates among children and young adults aged 24 years and younger in the US are particularly elevated due to injuries and drug overdoses.13<\/a><\/sup> Tragically, the pandemic dramatically increased income gaps in health and mortality, worsening both inequality in health care access and risks posed by external factors (eg, injuries, substance use, domestic violence).14<\/a><\/sup> Some of these factors may persist even as the pandemic winds down, making it more urgent to implement policies that enhance children\u2019s underlying health as well as continuing to preserve and expand access to medical care.<\/a><\/p>\n\n\n\n A 2019 report from the National Academy of Sciences laid out the evidence that there is a causal relationship between child poverty and poor child health, which works through many pathways including worse nutrition, inferior housing, chronic stress, violence, and exposure to environmental pollution.15<\/a><\/sup> The report predicted that child poverty could be reduced by half through a single policy measure\u2014the expansion of the Child Care Tax Credit. This policy was implemented in 2020, and data from the US Census Bureau showed that it helped to reduce child poverty by more than 40%, such that child poverty reached a record low of 5.2% in 2021.16<\/a><\/sup> However, the expanded credit was allowed to expire at the end of 2021. This example shows that child poverty, and its insidious effects on children\u2019s bodies and minds, is not a given but something that could be dramatically improved given the political will to fight it using proven policy tools.<\/p>\n","protected":false},"excerpt":{"rendered":" Editorial December 27, 2022 The Relatio […]<\/p>\n","protected":false},"author":3,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":[],"categories":[24,23],"tags":[],"_links":{"self":[{"href":"https:\/\/csccm.org.cn\/index.php?rest_route=\/wp\/v2\/posts\/23331"}],"collection":[{"href":"https:\/\/csccm.org.cn\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/csccm.org.cn\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/csccm.org.cn\/index.php?rest_route=\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/csccm.org.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=23331"}],"version-history":[{"count":1,"href":"https:\/\/csccm.org.cn\/index.php?rest_route=\/wp\/v2\/posts\/23331\/revisions"}],"predecessor-version":[{"id":23332,"href":"https:\/\/csccm.org.cn\/index.php?rest_route=\/wp\/v2\/posts\/23331\/revisions\/23332"}],"wp:attachment":[{"href":"https:\/\/csccm.org.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=23331"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/csccm.org.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=23331"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/csccm.org.cn\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=23331"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}