Medicaid improves access and chronic disease control

Medicaid coverage improves access to health care and chronic disease control: American Journal of Public Health study

Physicians for a National Health Program, November 12, 2015

Low-income Americans with Medicaid insurance have more awareness and better treatment of chronic diseases, such as high blood pressure, than their uninsured counterparts, a group of Harvard researchers said today. People with Medicaid are also five times more likely to see a doctor than those with no health insurance.

These are among the chief findings of a new study by a team of researchers led by Dr. Andrea Christopher, a fellow at Harvard Medical School, published today in the American Journal of Public Health. The study is based on data gathered from 4,460 poor Americans in national surveys conducted by the Centers for Disease Control and Prevention.


Access to Care and Chronic Disease Outcomes Among Medicaid-Insured Persons Versus the Uninsured

By Andrea S. Christopher, MD, Danny McCormick, MD, MPH, Steffie Woolhandler, MD, MPH, David U. Himmelstein, MD, David H. Bor, MD, and Andrew P. Wilper, MD, MPH
American Journal of Public Health, November 12, 2015 (Online ahead of print)


Objectives. We sought to determine the association between Medicaid coverage and the receipt of appropriate clinical care.

Methods. Using the 1999 to 2012 National Health and Nutritional Examination Surveys, we identified adults aged 18 to 64 years with incomes below the federal poverty level, and compared outpatient visit frequency, awareness, and control of chronic diseases between the uninsured (n = 2975) and those who had Medicaid (n = 1485).

Results. Respondents with Medicaid were more likely than the uninsured to have at least 1 outpatient physician visit annually, after we controlled for patient characteristics (odds ratio [OR] = 5.0; 95% confidence interval [CI] = 3.8, 6.6). Among poor persons with evidence of hypertension, Medicaid coverage was associated with greater awareness (OR = 1.83; 95% CI = 1.26, 2.66) and control (OR = 1.69; 95% CI = 1.32, 2.27) of their condition. Medicaid coverage was also associated with awareness of being overweight (OR = 1.30; 95% CI = 1.02, 1.67), but not with awareness or control of diabetes or hypercholesterolemia.

Conclusions. Among poor adults nationally, Medicaid coverage appears to facilitate outpatient physician care and to improve blood pressure control.

From the Introduction

The Affordable Care Act (ACA; Pub L No. 111---148) expanded Medicaid insurance for people with low incomes (<138% of the federal poverty level [FPL]) in 31 states. However, whether Medicaid coverage improves health outcomes remains controversial. Several studies described differences in chronic disease prevalence and control between uninsured persons and those with Medicaid, but have not been designed or powered to explore whether Medicaid coverage might cause these differences.

Recently, the Oregon Health Insurance Experiment (OHIE), a randomized, controlled trial, found that Medicaid coverage increased health care use, improved patients’ financial security and self-reported health, lowered depression rates, and raised diabetes diagnosis rates. However, the OHIE did not find improvements in other important health outcomes such as control of other chronic diseases, fueling Medicaid’s critics.

The rigorous design of the OHIE provides strong evidence on the impact of Medicaid in the Portland, Oregon, metropolitan area where it was conducted. However, Portland’s relatively robust medical safety net for the uninsured may have attenuated the potential for health improvements from Medicaid expansion compared with other locales, or the United States as a whole.

From the Discussion

Our findings suggest that, nationally, Medicaid was associated with improved access to outpatient medical care, as well as awareness and control of important chronic conditions. Medicaid recipients visited health care providers much more frequently than comparable uninsured individuals, and were more likely to be aware of their hypertension and overweight. In addition, Medicaid recipients were more likely to have their blood pressure controlled, a clinical goal known to reduce all-cause mortality by as much as 17%. However, we found no differences in the diagnosis or control of diabetes, and only nonsignificant differences among those with hypercholesterolemia. We theorize that the lack of findings for diabetes may be because control requires more significant diet and lifestyle changes compared with other chronic conditions, and these changes may not be easily remedied through access to medical care.

Our findings differ from those in the OHIE. First, in the Oregon study, outpatient visits among uninsured individuals averaged 5.5 per year, whereas we found that more than 60% of uninsured individuals nationally had zero or 1 outpatient visit per year. Second, whereas the OHIE observed a 50% increase in outpatient visits among the Medicaid population, we found substantially larger national effects (a 5.0-fold increased odds). Despite methodological differences that preclude exact comparisons with the OHIE data (the NHANES coded outpatient visits into categories), our results suggest that outpatient health care use by the uninsured nationally is probably lower than that of the OHIE’s control population and the boost from Medicaid somewhat bigger. Third, the OHIE found significantly increased detection of diabetes but not hypertension or obesity, and did not show improvement in any physical health measures.

For states that expanded Medicaid under the ACA, enrollment began only 1 year ago; several states are considering expanding Medicaid in the future. Thus, it will likely take several years before nationally representative data become available on the ACA’s impacts. Our data on the association of Medicaid coverage with both outpatient visit frequency and chronic disease care in the pre-ACA era help inform projections of the impact of the largest expansion of Medicaid since its founding.



By Don McCanne, M.D.

Opponents of the Affordable Care Act have been using the Oregon Health Insurance Experiment (OHIE) to supposedly show that Medicaid does not improve health outcomes even though the study was not powered to demonstrate such. Thus this new study is important because it does show that Medicaid improves access, improves awareness of important chronic conditions, and improves control of hypertension. The OHIE trial did show that “Medicaid coverage increased health care use, improved patients’ financial security and self-reported health, lowered depression rates, and raised diabetes diagnosis rates.”

Clearly Medicaid is of benefit. However, as a chronically underfunded welfare program, Medicaid does have significant deficiencies. Last week, a UC Davis study reported that cancer care is worse for Medicaid patients than for other insured patients. The question is, what should we do about it?

Some conservatives would convert Medicaid into a block grant to the states, limiting federal contributions, likely compounding the problem of underfunding. Other conservatives would eliminate Medicaid and place everyone in high-deductible private plans, perhaps with some federal contributions to health savings accounts for low-income individuals. Narrow networks and cost sharing would surely limit access for this population.

A much better solution would be to replace our fragmented health care financing system with a single payer national health program, eliminating cost sharing and network barriers. Since the program would cover all of us, chronic underfunding for a sector of us would not be tolerated.