The Effect of Medicaid on Dental Care of Poor Adults: Evidence from the Oregon Health Insurance Experiment.

OBJECTIVE: To evaluate the effect of Medicaid coverage on dental care outcomes, a major health concern for low-income populations. DATA SOURCES: Primary and secondary data on health care use and outcomes for participants in Oregon\u27s 2008 Medicaid lottery. STUDY DESIGN: We used the lottery\u27s random selection to gauge the causal effects of Medicaid on dental care needs, medication, and emergency department visits for dental care. DATA COLLECTION: Data were collected for lottery participants over 2 years, including mail surveys (N = 23,777) and in-person questionnaires (N = 12,229). Emergency department (ED) records were matched to lottery participants in Portland (N = 24,646). PRINCIPAL FINDINGS: Medicaid coverage significantly reduced the share of respondents who reported needing dental care (-9.8 percentage points, p \u3c .001) or having unmet dental care needs (-13.5 percentage points, p \u3c 0.001). Medicaid doubled the share visiting the ED for dental care (+2.6 percentage points, p = .003) and the use of anti-infective medications often prescribed for dental care, but it had no detectable effect on uncovered dental care or out-of-pocket spending. CONCLUSIONS: Expansion of Medicaid covering emergency dental care substantially reduced unmet need for dental care, increasing ED dental visits and medication use, while not changing patient use of uncovered dental services

The Effect of Medicaid on Management of Depression

Context Expanding Medicaid to previously uninsured adults has been shown to increase detection and reduce the prevalence of depression, but the ways that Medicaid affects mental health care, how effectively it addresses unmet needs, and how those effects differ for those with and without a history of depression remain unclear. Methods We take advantage of Oregon's Medicaid lottery to gauge the causal effects of Medicaid coverage using a randomized‐controlled design, drawing on both primary and administrative data sources. Findings Medicaid coverage reduced the prevalence of undiagnosed depression by almost 50% and untreated depression by more than 60%. It increased use of medications frequently prescribed to treat depression and related mental health conditions and reduced the share of respondents reporting unmet mental health care needs by almost 40%. The share of respondents screening positive for depression dropped by 9.2 percentage points overall, and by 13.1 for those with preexisting depression diagnoses, with greatest relief in symptoms seen primarily in feeling down or hopeless, feeling tired, and trouble sleeping—consistent with the increase observed not just in medications targeting depression but also in those targeting sleep. Conclusions Medicaid coverage had significant effects on the diagnosis, treatment, and outcomes of a population with substantial unmet mental health needs. Coverage increased access to care, reduced the prevalence of untreated and undiagnosed depression, and substantially improved the symptoms of depression. There are likely to be substantial mental health consequences of policy decisions about Medicaid coverage for vulnerable populations. Keywords: Medicaid; insurance; depression; mental healthNational Institute on Aging (Grant P30AG012810)National Institute on Aging (Grant RC2AGO36631)National Institute on Aging (Grant R01AG0345151)National Bureau of Economic Research (Grant 5 RRC 08098400‐03‐00

Effect of Medicaid Coverage on ED Use — Further Evidence from Oregon’s Experiment

The effect of Medicaid coverage on health and the use of health care services is of first-order policy importance, particularly as policymakers consider expansions of public health insurance. Estimating the effects of expanding Medicaid is challenging, however, because Medicaid enrollees and the uninsured differ in many ways that may also affect outcomes of interest. Oregon’s 2008 expansion of Medicaid through random-lottery selection of potential enrollees from a waiting list offers the opportunity to assess Medicaid’s effects with a randomized evaluation that is not contaminated by such confounding factors. In a previous examination of the Oregon Health Insurance Experiment, we found that Medicaid coverage increased health care use across a range of settings, improved financial security, and reduced rates of depression among enrollees, but it produced no detectable changes in several measures of physical health, employment rates, or earnings

Intervening on risk factors for coronary heart disease: an application of the parametric g-formula

Estimating the population risk of disease under hypothetical interventions—such as the population risk of coronary heart disease (CHD) were everyone to quit smoking and start exercising or to start exercising if diagnosed with diabetes—may not be possible using standard analytic techniques. The parametric g-formula, which appropriately adjusts for time-varying confounders affected by prior exposures, is especially well suited to estimating effects when the intervention involves multiple factors (joint interventions) or when the intervention involves decisions that depend on the value of evolving time-dependent factors (dynamic interventions). We describe the parametric g-formula, and use it to estimate the effect of various hypothetical lifestyle interventions on the risk of CHD using data from the Nurses’ Health Study. Over the period 1982–2002, the 20-year risk of CHD in this cohort was 3.50%. Under a joint intervention of no smoking, increased exercise, improved diet, moderate alcohol consumption and reduced body mass index, the estimated risk was 1.89% (95% confidence interval: 1.46–2.41). We discuss whether the assumptions required for the validity of the parametric g-formula hold in the Nurses’ Health Study data. This work represents the first large-scale application of the parametric g-formula in an epidemiologic cohort study