LOS ANGELES – The use of clot-busting drugs in patients with mild stroke could save thousands of them from long-term stroke-related disability, and about $200 million each year in stroke-related health care costs.
The decision to administer tissue plasminogen activator (tPA) to patients with mild stroke is a difficult one, balancing the possible benefits with the risk of further bleeding, Dr. Pooja Khatri said during a press briefing at the International Stroke Conference. But her epidemiologic study of 150 mild strokes – only four of which were treated with tPA – suggests that administering the drug could prevent the disability that affects up to one-third of these patients.
Her retrospective study drew its data from the Greater Cincinnati/Northern Kentucky Stroke Study. The database included 441 patients in that region who were treated for ischemic stroke during 2005. Of those, 56% (247) had strokes that were considered mild, with a baseline modified Rankin Scale score of 2-6. And, of those patients, 62% (150) were considered eligible for tPA treatment; however, only 1% (4) received the drug.
Dr. Khatri, director of acute stroke at the University of Cincinnati Academic Health Center, did not follow the patients to compare clinical outcomes over time. However, she said, based on two extant studies, about 30% of mild stroke patients do experience deficits that affect their lives. "These tend to be on the milder end of the spectrum, but it’s still disability," she said in an interview. "They might not able to drive, go back to work, or take care of themselves. They can still walk, but they are not the same person they used to be."
She extrapolated her findings to the entire U.S. population in 2010, estimating that mild strokes would have occurred in 27,203 patients without baseline disability. If all of the these patients had received an effective treatment, such as the current clot-busting drugs or a milder form that could be developed, up to 13% (3,761) could be saved from disabling stroke-related disability.
The estimated annual cost savings could be immense, she said. "We could see a savings of $200 million across the country," an estimate that includes the potential costs of adverse events associated with widening the treated population.
But her data don’t directly address the day-to-day decisions clinicians have to make when faced with a mild stroke patient. A tiny fraction of mild stroke patients receive tPA treatment, she said, because generally the potential gains are regarded as small, compared with the risk of aggravated brain hemorrhage. Most of the time, things go well when treating mild stroke patients, because the risk of bleeding lessens with stroke severity. "But sometimes we get burned," Dr. Khatri said. "That [untreated] patient may end up being paralyzed on one side or having cognitive problems that we didn’t recognize in the emergency department. On the other hand, we may treat and that patient can bleed and perhaps even die." The dilemma can be answered only by a large, randomized trial, she said – something she and her colleagues at the University of Cincinnati are trying to get started.
"Our group is planning such a study, to randomize those with mild stroke to tPA or placebo and then follow them, characterizing their hemorrhage rates as well as their disability outcomes."
Dr. Khatri’s study was sponsored by the National Institutes of Health; neither she nor any coauthors had any financial disclosures.