ARTICLE IN BRIEF
A new study found that thrombolysis is safe for elderly demented patients.
DR. AMER ALSHEKHLEE ...Image Tools
Thrombolysis is as safe for demented elderly patients as it is for elderly patients with normal cognition, according to a study that compared safety outcomes from over 800 elderly patients receiving tissue plasminogen activator (tPA) after stroke.
“The message of this study is simple,” said Neurology Today Associate Editor Robert G. Holloway Jr., MD, professor of neurology and community and preventive medicine at the University of Rochester Medical Center in New York, who was not involved with the study. “It gives me further reassurance that, in general, tPA in patients with dementia is safe.”
The question of whether thrombolysis with tPA is safe in elderly patients with dementia is important, said the study's lead author Amer Alshekhlee, MD, associate professor of neurology at St. Louis University in Missouri. “Most clinical trials in the past have not included the elderly population, so it remains a debatable subject whether to treat the elderly with dangerous and expensive therapies such as tPA.”
A previous study by Dr. Alshekhlee showed that safety outcomes were similar following treatment in elderly versus younger stroke patients with normal cognition. The current study, published in the March 30 online edition of Neurology, addresses whether the same is true of those elderly patients with dementia. A key concern is that elderly demented patients are at higher risk of cerebral microbleeds, and microbleeds have been considered a risk factor for larger hemorrhages, a major complication with tPA treatment.
Stroke-associated ho...Image Tools
To address whether dementia increases the risk of thrombolysis in demented elderly patients, Dr. Alshekhlee examined medical records from the National Inpatient Database, which contains records from 20 percent of all hospitals in the US. Almost half a million patients were admitted with acute ischemic stroke during the time period of the study, of whom over 35,000 were demented, as determined by ICD-9-M codes. Of these, 207, or 0.56 percent, received thrombolysis. Dr. Alshekhlee chose a matched population of 621 non-demented elderly stroke patients who also received treatment as a comparator group. The mean age of both groups was 81 years.
Seventeen percent of the demented patients and 14 percent of the non-demented patients died following treatment, a difference that was not statistically significant. Similarly, 6 percent of demented patients and 5 percent of non-demented patients experienced intracerebral hemorrhage.
The two groups were also compared for rates of sepsis, gastrointestinal hemorrhage, and intubation due to respiratory failure. Only the intubation rate differed, occurring in 3 percent of demented patients and 11 percent of non-demented patients, possibly reflecting a more conservative approach on the part of physicians, or a higher percentage of advance directives contraindicating intubation, in demented patients, Dr. Alshekhlee said.
The results “suggest that it is fairly safe to treat the elderly and demented person. It is quite clear from the data,” Dr. Alshekhlee said.
Dr. Alshekhlee noted that the study did not look at the effect of dementia on the efficacy of thrombolysis. “This requires a prospective study,” he said, but there is no suggestion in the literature that the results should differ from those in non-demented patients.
“I think neurologists should have a positive attitude” about thrombolysis when they encounter an older person with dementia,” he added.
Dr. Alshekhlee noted that the overall rate of tPA treatment in all stroke patients is very low, a trend that is even more pronounced in the elderly, with only about 1 percent of elderly stroke patients receiving treatment.
The results of this study combined with other recent data suggesting tPA is safer than previously thought in a wide variety of populations, Dr. Holloway said. “There has been a lot of new information in the past year that in stroke, when there are other things to consider,” including dementia or advanced age, “and even if you get the diagnosis wrong, and it's not even a stroke — for example, it's migraine, post-seizure, or conversion disorder — that tPA is generally safe. But, he added, echoing Dr. Alshekhlee, “It still doesn‘t answer the question of whether you should give it.”
“But I think this paper gives me that little extra reassurance in conversations with patients, surrogate decision-makers, emergency department personnel, geriatricians, or fellow general neurologists, that I can say, ‘We know there are risks, but patients with dementia don‘t appear to have any extra risks compared to patients without dementia.‘ It gives me a little extra confidence that it is probably more safe than we thought.”
The data in the study also point out a much more significant problem in stroke treatment — the very small fraction of stroke patients of any group who receive thrombolysis. “I do not know what the ‘right‘ rate of tPA administration is for this population, but 0.5 percent is very likely lower than it should be,” Dr. Holloway said.
“Many more people should be offered tPA,” said Vladimir Hachinski, MD, professor of neurology at the University of Western Ontario in London, Canada. Awareness of stroke symptoms is a major barrier.
“Only a minority of individuals, even among the age group that is at higher risk, are aware of what the symptoms are,” said Dr. Hachinski, who serves on the editorial advisory board of Neurology Today. As a result, many stroke victims don‘t seek treatment until well past the window in which tPA can be given. “We need a big educational program to teach people.”
Physicians also need education, to encourage them to treat stroke more aggressively. “Physicians have always been afraid of the brain. We need to overcome that fear. Emergency physicians wouldn‘t think twice about treating a heart attack aggressively, and yet they hesitate to treat the brain. The truth is that while the brain is complex when it is operating normally, it fails in a few predictable ways.”
And tPA need not be administered by neurologists with expertise in stroke. “We need more stroke doctors, but there are very few of us,” Dr. Hachinski said, “and we have to make tPA more widely available. Emergency room physicians and internists can learn to do it well.”
Alshekhlee A,Li C-C, Cruz-Flores S, et al. Does dementia increase risk of thrombolysis?: A case-control study. Neurology 2011; E-pub 2011 March 30.
©2011 American Academy of Neurology