With Expansion of Medicaid, Some States Are Identifying More New Diabetes CasesApril 2, 2015
The number of new diabetes cases identified among poor Americans has surged in states that have embraced the Affordable Care Act, but not in those that have not, a new study has found, suggesting that the health care law may be helping thousands of people get earlier treatment for one of this country’s costliest medical conditions.
One in 10 Americans have diabetes, and nearly a third of cases have not been diagnosed. The disease takes a toll if it is caught too late, eventually causing heart attacks, blindness, kidney failure and leg and foot amputations. The Centers for Disease Control and Prevention estimates that the disease accounts for $176 billion in medical costs annually. The poor and minorities are disproportionately affected.
The health care law aimed to bring many of the most disadvantaged Americans into the medical system by expanding access to Medicaid, the government insurance program for the poor. But with the release of federal health data still months away, it was impossible to know whether the new coverage was having any effect in identifying and treating critical health problems such as diabetes and high blood pressure.
In the new study by Quest Diagnostics, a medical testing company, researchers analyzed laboratory test results from all 50 states in the company’s large database over two six-month periods. In the states that expanded Medicaid, the number of Medicaid enrollees with newly identified diabetes rose by 23 percent, to 18,020 in the first six months of 2014, from 14,625 in the same period in 2013. The diagnoses rose by only 0.4 percent — to 11,653 from 11,612 — in the states that did not expand Medicaid.
In all, the Quest study identified 434,288 people as having diabetes — equal to about a quarter of all new American cases in a year, according to the most recent federal data.
The number of Americans with diabetes more than tripled from 1990 to 2010, according to federal data. Nearly all the increase came from Type 2 diabetes, which is often related to obesity and is the more common form of the disease. In recent years, the pace of new diagnoses has slowed, and major strides have been made in reducing mortality and some of the worst complications.
The authors of the study, published Monday in the journal Diabetes Care, said it was a natural experiment: About half the states had chosen to expand Medicaid by early 2014 and half had not. The research team used what medical experts agreed was a reasonable proxy for a diabetes diagnosis — the results of a test, called hemoglobin A1c, that reflects long-term glucose in the blood.
The study had limitations. Unlike federal data, which are designed to be nationally representative, researchers in this case looked at changes in raw numbers of the lab results from one company.
Dr. Elbert Huang, a diabetes researcher at the University of Chicago, said he was not convinced that the rise in diagnoses among Quest patients was the result of the new health law, rather than, for example, a population increase in states that expanded Medicaid or a jump in Quest’s market share in those states. “I’m quite skeptical of these conclusions,” he said.
Dr. Harvey Kaufman, senior medical director at Quest Diagnostics and an author of the study, said Quest’s market share did not change much from 2013 to 2014, and that the modest population increase over the study period was unlikely to explain the magnitude of the rise of new diabetes patients in states that had expanded Medicaid.
The total number of new patients, not just those on Medicaid, rose by about 1.6 percent in the study period, roughly in line with the most recent increase of the national population, he said.
A number of researchers not involved in the study said that while it did not have the precision of a scientific drug trial or a federal data set, its conclusions were telling.
“We don’t know what the numbers are for everybody,” said Dr. Richard W. Grant, a researcher at Kaiser Permanente, a large health insurer and care provider. “We just know the change for Quest. But that change was real. And it was not splitting hairs — 23 percent versus zero.”
Dr. David M. Nathan, director of the Diabetes Center at Massachusetts General Hospital, said earlier detection — particularly among the poor, who are more likely to have the disease without knowing it — is the first step in preventing some of the most severe long-term consequences and saving dollars and lives. He pointed out that diabetes rates tended to be highest in the Southern states that did not expand Medicaid, and that full insurance coverage there would likely produce an even stronger effect.
“This suggests that states that are accepting this kind of coverage are doing their populations a huge favor,” he said, adding that the health care law was the most plausible explanation for the findings. “I couldn’t find anything that sounded like a false note,” he said of the study.
Dr. William C. Knowler, chief of diabetes epidemiology and clinical research at the National Institute of Diabetes and Digestive and Kidney Diseases branch in Phoenix, called the study “an opportunistic analysis of data,” but said the conclusion was convincing because the numbers were so stark. But he cautioned that science had not proved that early diagnosis changed long-term outcomes like kidney and heart complications and mortality for the better.
“I’m not arguing that early detection is not beneficial, but it’s more a matter of faith than data,” Dr. Knowler said.
Dr. Richard Beaser, a clinician at Joslin Diabetes Center, a nonprofit research and clinical group in Boston, said of the study’s conclusion: “Is it 100 percent etched in stone? No. But for an observational study, it’s really very strong. It passes my smell test, I tell you that much.”