Medicaid recipients undergoing spine surgery experience more complications than privately insured patients do, according to a study in the July 15, 2013 issue of Spine. The findings are consistent with research showing poor health outcomes and increased mortality among uninsured and Medicaid patients in many areas of medicine.

The new research has particular significance for Medicaid patients with spinal arthritis: At least a quarter of those in the current study had surgery for degenerative changes in the spine.

Lead author Jacques Hacquebord, MD, an orthopaedic surgery resident in the Department of Orthopaedics and Sports Medicine at the University of Washington in Seattle, says understanding which patients are likely to experience complications is essential for improving surgical outcomes. Building on previous studies, he and colleagues at the University of Washington and Harborview Medical Center in Seattle looked at insurance status as a possible risk factor for complications after spine surgery.         

The researchers analyzed a database of nearly 1,600 people who underwent spine procedures in 2003 and 2004 at two academic hospitals: a university based medical center, and a county hospital serving as the only level I trauma center in a large multistate area. About half the patients were covered by government-funded programs such as Medicare, which insures older adults, and Medicaid, which covers low-income Americans. Thirty-eight percent were privately insured; the rest had other sources of insurance or were self-pay. The patients were followed for two years.

After taking into account a patient’s age and health status, as well as the reason for the surgery and how invasive it was, the results showed that Medicare patients did not have an increased risk of complications after spine surgery, but Medicaid recipients did. In fact, when Medicaid was the insurer, patients were 68 percent more likely than privately insured patients to develop one or more complications.

"It's important in looking at data to control for factors such as age, sex, comorbidities, body mass index, smoking and surgical invasiveness," Dr. Hacquebord says. "And once those factors are teased out, we wanted to see if payor status by itself could be a risk factor for postoperative complications."

Researchers defined complications as an "adverse event" in a major organ system: cardiac, pulmonary, gastrointestinal, neurological, hematological and urological. The most common, according to Dr. Hacquebord, were heart attack, pulmonary embolism and kidney failure.

The researchers offer several explanations as to why Medicaid patients do so poorly. One is that Medicaid may not cover all the care patients need to recover fully after surgery – a problem they refer to as underinsurance.

"We tend to think of people as being insured or not insured, but it's not that black and white," Dr. Hacquebord says. "It is important to know that just having insurance doesn't solve every problem. It might not be an appropriate level that allows people to get the [postsurgical] care they need without having to incur unsustainable financial burdens." Furthermore, he says, "a lack of resources may prevent patients from following physician recommendations."

Medicaid patients also have less access to medical care than the privately insured. According to the Centers for Medicare and Medicaid Services (CMS), fewer than half of U.S. doctors and other health care providers accept Medicaid patients. For those who do, wait times can be months. And the problem will likely worsen by 2016, when almost 30 million people become insured under the Patient Protection and Affordable Care Act (a.k.a. "Obamacare") – many under Medicaid. 

Ultimately, researchers say, Medicaid status is the tip of the iceberg – underinsured patients often have difficult life circumstances that can negatively affect surgical outcomes and overall health.

"Insurance status is … a proxy for socioeconomic status, for people who have certain economic and social challenges that others don't," says senior study author Michael J. Lee, MD, associate professor of orthopaedics in the Department of Orthopaedics and Sports Medicine at the University of Washington in Seattle.