Study finds link between insurance type and treatment for stroke patients

University of Florida researchers have found a correlation between Medicare and patient access to surgical treatment for subarachnoid hemorrhage, a type of stroke that affects as many as 30,000 Americans each year — often causing death or long-term impairment and disability.

For patients who have suffered this type of stroke, surgical intervention can spell the difference between recovery or long-term disability and death, yet patients on Medicare are less likely than those with private insurance to be referred for surgical treatment, according to findings published Aug. 20 in the journal PLOS ONE. This may represent a conscious or unconscious bias against Medicare patients, who are typically older and have preexisting disabilities or chronic illnesses, said Azra Bihorac, M.D., senior author of the study and an associate professor of anesthesiology, medicine and surgery at the UF College of Medicine.

“Not every hospital has skilled neurosurgeons who specialize in subarachnoid hemorrhage,” Bihorac said. “If these hospitals don’t have the necessary expertise, then they may actually overestimate the risk of a bad prognosis. They may assume that the patient won’t do well anyway, so they won’t proceed with surgery.”

For the study, the researchers analyzed data from the National Inpatient Sample hospital discharge database. The data includes information on more than 21,000 adult patients discharged from 2003 to 2008 with a diagnosis of subarachnoid hemorrhage. Approximately 62 percent of the sample was female and the mean age was 59 years — younger than is typical with other types of stroke.

Compared with privately insured patients, Medicare patients were almost 45 percent less likely to undergo surgical treatment and were more than twice as likely to die in the hospital. This may be because Medicare patients tend to be older or have additional health issues, said lead author Charles Hobson, M.D., M.H.A., a surgical critical care specialist at the Malcom Randall Veterans Affairs Medical Center and a doctoral candidate in the UF College of Public Health and Health Professions.

“It’s not that you don’t get surgery because you have Medicare — your doctor isn’t checking your insurance,” he said. “But having Medicare as primary health insurance may be a proxy for bias against the elderly and those with chronic illnesses.”

Subarachnoid hemorrhage accounts for 5 percent of all strokes, according to the American Heart Association. It occurs when there is bleeding in the area between the brain and the thin tissues that cover the brain, most often caused by an aneurysm. The condition causes sudden, severe head pain and must be treated immediately to prevent brain injury, disability and death. Risk factors include a family history of aneurysms, high blood pressure and smoking.

Approximately 10 to 15 percent of these patients die before reaching the hospital. For those who survive, the next 48 hours are critical, Bihorac said. During this time, the main goal of the treatment team is to stop the patient from re-bleeding, a repeated rupture in the same location of the aneurysm and the leading cause of death in people who survive the initial hemorrhage.

A combination of early interventions including medications to lower a patient’s blood pressure can help reduce the chance of re-bleeding, but surgical treatment to repair the aneurysm has been shown to decrease both illness and death after subarachnoid hemorrhage, Hobson said.

The study found that patients who did not undergo surgical treatment were twice as likely to die than those who did have surgery. In addition, patients who survived the first 48 hours without surgery had a greater risk of developing a severe disability or cognitive impairment.

However, only about one third of all subarachnoid hemorrhage patients in the United States actually receive some form of surgical treatment.

“Surgery is valuable — really, essential — if you’re going to have a good outcome,” Hobson said. “But we’ve found that if there are two people who are otherwise the same, but one is either elderly or has chronic illness or disability, he or she is less likely to undergo surgery.”

While the researchers believe there is a bias regarding these patients, two-thirds of all people treated for subarachnoid hemorrhage do not receive surgical treatment to repair the aneurysm. One contributing factor is the small percentage of patients who bleed without having an aneurysm, but this alone does not explain the substantial number of people who go without surgical treatment, Bihorac said. She believes that one reason for this is a lack of standard of care for subarachnoid hemorrhage.

“A lot of things are left up to the subjective assessment of the provider who first sees the patient,” Bihorac said. “Each provider has his or her own biases. They can be rational, they can be made from past experience — but these biases do interfere.”

This bias is of particular concern if a patient seeks treatment at a hospital that only sees a few subarachnoid hemorrhage cases each year or is without the necessary diagnostic tests or specialists in place, she said.

Indeed, the study found that patients treated at teaching hospitals, as well as hospitals that see a high volume of subarachnoid hemorrhage patients, were more likely to undergo surgical treatment.

A potential solution for the discrepancy would be for state government to enforce regionalized care for subarachnoid hemorrhage, as is currently standard for certain trauma and neonatal issues, Hobson said.

“Despite the improvements in care over the last 10 years in subarachnoid hemorrhage, the percent of people not receiving surgery is unchanged — which is another argument for dealing with this issue on a systemic level, not an individual provider level,” he said. “With regionalized care, the moment an ER doc sees a bleed, it would trigger a system — ‘OK, this patient needs to go to a place where the experts can decide whether or not he needs surgery.’ The clock is ticking.”