Medicaid vs ACA Cost Sharing Reduction choices

In the short thread celebrating North Carolina starting Medicaid Expansion last Friday, Freemark asked a good question:

What do you think is better, Medicaid or high CSR Silver? Had some time off work and will probably qualify for Medicaid but could move $2000 from an old 401k to a Roth and that would put me just enough to get a high CSR plan. No premium, to me, $1 copay and a $300 deductible.

Like most health policy questions, the honest answer is “It’s messy and it really depends on your values, preferences and situation….”

However, one of my mentors and committee members, Dr. Heidi Allen looked at this question in a 2021 JAMA Network Open article. Her team linked Colorado enrollment into ACA and Medicaid data with the state all payer claims database. They looked at individuals whose income was just above and just below the 138% Federal Poverty Level eligibility line. People with incomes above that line went to CSR plans and people within incomes below that line went to the Medicaid Expansion pool. The study looks at total costs, out of pocket spending and a dozen quality metrics:

Here are there key results:

Marketplace coverage was associated with fewer ED visits (mean, 0.36 [95% CI, 0.32-0.40] visits vs 0.56 [95% CI, 0.50-0.62] visits; P < .001) and more office (outpatient) visits than Medicaid (mean, 2.22 [95% CI, 2.11-2.32] visits vs 1.73 [95% CI, 1.64-1.81] visits; P < .001). No differences in ambulatory care–sensitive hospitalizations were found (0.004 [95% CI, 0.001-0.006] vs 0.007 [95% CI, 0.002-0.011]; P = .15). Total costs were 83% higher in Marketplace coverage (mean, $4553 [95% CI, $3368-$5738] vs $2484 [95% CI, $1760-$3209]; P < .001) owing almost entirely to higher prices, and out-of-pocket costs were 10 times higher (mean, $569 [95% CI, $337-$801] vs $45 [95% CI, $26-$65]; P < .001). Five of 12 secondary quality measures favored private insurance, and 1 favored Medicaid.

ACA plans will steer people out of emergency rooms and to outpatient facilities more aggressively. There is a lot more cost sharing in the ACA ($569 vs $45 for Medicaid). Quality probably is neutral to ACA favoring on most things.

There are two generalizability problems. First, Colorado’s Medicaid program is relevant for Colorado. Medicaid in West Virginia pays doctors and hospitals way worse so ACA plans which pay better are likely to get more of an access bonus than Colorado plans. Conversely, Medicaid pays relatively well in Ohio, so there might be less of an access bump. Secondly, they only look at people who are really close to the switch line. Folks who are pretty far away from the line might have different things going on in their lives.

Finally, the big thing is how much do you value your current provider relationships and access? If you’re routinely seeing doctors and using services, your value on a relationship is likely higher than someone who has seen a doctor twice in the past five years.