Objective: To determine whether Massachusetts Health Reform improved health outcomes in uninsured patients with hyperlipidemia, diabetes, or hypertension.
One of the critical questions about health care reform asks how much good reform will do to improve the quality of people's health. Yes, insurance is about more than outcomes. It's also about giving people peace of mind and providing them with financial security. But it's also about making people healthier.
Does it do that? After the results of the Oregon Insurance Health Experiment, many debated this issue. Some of the papers claimed that providing people with Medicaid did little to improve chronic disease. Some, like Austin and I, argued that the study wasn't really powered to answer these questions. But that doesn't mean those questions shouldn't, or can't, be answered.
A recent paper in HSR adds to our fund of knowledge. "Effect of Massachusetts Health Reform on Chronic Disease Outcomes":
Data Source: Partners HealthCare Research Patient Data Registry (RPDR).
Study Design: We examined 1,463 patients with hyperlipidemia, diabetes, or hypertension who were uninsured in the 3 years before the 2006 Massachusetts Health Reform implementation. We assessed mean quarterly total cholesterol, glycosylated hemoglobin, and systolic blood pressure in the respective cohorts for five follow-up years compared with 3,448 propensity score-matched controls who remained insured for the full 8-year study period. We used person-level interrupted time series analysis to estimate changes in outcomes adjusting for sex, age, race, estimated household income, and comorbidity. We also analyzed the subgroups of uninsured patients with poorly controlled disease at baseline, no evidence of established primary care in the baseline period, and those who received insurance in the first follow-up year.
This study compared 1,463 uninsured patients and 3,448 insured patients, who had hyperlipidemia, diabetes, or hypertension, in the three years before reform in Massachueetts and the five years after. They matched them by propensity score, and controlled analyses for demographic factors and comorbidities. This isn't a randomized controlled trial, so it's not proof of causality, but it's a good effort to look at whether becoming insured is associated with improvements in chronic disease management.
The study's main findings were that patients who were uninsured before reform didn't have a bigger improvement in total cholesterol, HbA1c level, or systolic blood pressure compared to those who were insured over the entire period. They also looked specifically at patients who had the most potential to see improvement: those who had poorly controlled disease before reform, had no established primary care before reform, and who obtained insurance in the first follow-up year after reform. Even those patients showed no significant improvement over those who were already insured.
The main conclusion of the study is correct. Health care reform in Massachusetts wasn't associated with improvements in the care of these diseases five years later. But let's take a pause and look at some of the underlying factors of this study.
The first thing to note is that, by design, this study matched the controls, who were insured, to the uninsured population in such a way as to make them as alike as possible. When you look at Figure 1, you see that the levels of cholesterol, HgA1c, and systolic blood pressure were remarkably similar. If that's the case, one of two things might be true. The uninsured in Massachusetts might already be healthier than we'd expect, or the population matching caused a selection of patients from the insured population who were unhealthier than we'd expect. The former would bias this study towards the null, and latter would bias the study the other direction.
This is also a study of patients in Massachusetts. The state, even before reform was relatively generous in terms of providing uncompensated care. It had a low level of uninsurance. It had a high concentration of providers. Massachusetts is not the rest of the United States.
It's also important to note that in the studies that have "proven" that insurance improves these factors looked at very poorly controlled individuals. The uninsured in this study don't really qualify there. As best as I can tell from Figure 1, the baseline serum cholesterol value is about 220, the baseline HgA1c around 8, and the baseline systolic blood pressure just above 130. Those values, while high, are not the same as those in prior studies.
The more important take home, however, and one recognized by the authors as well, is this: "Interventions beyond insurance coverage might be needed to improve the health of chronically ill uninsured persons." Insurance is necessary, but not sufficient to improve outcomes. You need it to gain access, but there's plenty of evidence that even people in the health care system have sub-optimal outcomes. Expecting that that insurance reform alone will improve quality is somewhat short-sighted.