The Stroke Prevention in Atrial Fibrillation (SPAF) Trials, a series of nationwide studies conceived at and led by the Health Science Center, prompted treatment changes that are preventing nearly 15,000 strokes a year in the U.S. and will save the country more than $1.2 billion in health care costs over a decade, according to a report published April 22 in the British medical journal The Lancet.
A California team examined the impact of eight American clinical trials funded by the National Institute of Neurological Disorders and Stroke before 2000, including the SPAF Trials. The SPAF studies were conducted at centers nationwide between 1987 and 1999 with neurologists Robert Hart, M.D., and David Sherman, M.D., of the Health Science Center as the principal investigators. The Lancet report, which inflated trial costs to 2004 U.S. dollars based on a medical services component of the U.S. Consumer Price Index, projected that the SPAF Trials, funded at $42.7 million in 2004 dollars, will show a 3,000 percent return on investment by 2010.
Atrial fibrillation, a quivering of the heart’s upper-right chamber that results in rapid, irregular pulse, may give rise to blood clots that block arteries and cause ischemic stroke. More than 2.2 million Americans have been diagnosed with atrial fibrillation and are at increased risk for ischemic stroke, the type of stroke resulting from lack of oxygen to the brain.
“During the first phase of SPAF, we showed that daily administrations of warfarin, an anti-clot agent, reduced the risk of ischemic stroke in atrial fibrillation patients by two-thirds,” Dr. Hart said. “We also showed that daily aspirin alone reduced the risk by 20 percent.”
SPAF enrolled 3,950 patient volunteers, including 350 from the San Antonio area. Most of the Hispanic participants were from San Antonio. “We can’t overemphasize the debt of gratitude we owe our volunteers,” Dr. Hart said. “We know how to prevent stroke in atrial fibrillation because of them. Their contributions helped not only themselves, but successive generations. This is an example of how people with a neurological disease can work together to conquer it.”
The SPAF Trials, which in San Antonio enrolled patients from clinics in the University Health System and the South Texas Veterans Health Care System, led to stratification of patients based on stroke risk and potential to benefit from therapy. Some patients, such as those with consistently high blood pressure, may not be able to take warfarin because of risk of bleeding.
Drs. Hart and Sherman thought up the SPAF study in 1985 in a lab at the Health Science Center. The institution was in its second decade, and Dr. Hart “wondered if two people in the ‘far hinterlands of medical research’ could get this off the ground. We did, and the success we had in leading the SPAF Trials directly contributed to our follow-up studies, called Secondary Prevention of Small Subcortical Strokes, or SPS3, under the direction of principal investigator Oscar Benavente, M.D. Atrial fibrillation is one cause of ischemic stroke, and in SPS3 we shifted to another cause, small subcortical strokes, which are equally frequent and occur at twice the national average in our community with its large Hispanic population.” The National Institute of Neurological Disorders and Stroke funded SPS3 at $37 million and the trial is now in 50 centers.
“Sometimes when research is being done and millions of dollars are being spent on it, people think it is an awfully high price to pay, but when you look at the benefits – and this analysis was done by an independent group – you can see the payback over the long haul,” Dr. Sherman said.
“Inclusion in the analysis indirectly points out that while there have been a number of atrial fibrillation studies for stroke prevention, it is becoming more the case that people consider the SPAF studies to be the most important ones,” Dr. Sherman added. “I believe the SPAF studies will go down in history as being the pivotal studies. It is gratifying that a homegrown study here in San Antonio is recognized around the world as the important one, and is the study they refer to consistently as the one that led the way in how to manage these patients.”
The authors of The Lancet article point out that for a variety of reasons, the analysis led to conservative estimates of the benefits of the clinical trials studied.
A stroke survivor story is featured in the HSC News’ After Hours feature section. Click here to learn more:www.uthscsa.edu/hscnews/singleformat.asp?newID=2029
A California team examined the impact of eight American clinical trials funded by the National Institute of Neurological Disorders and Stroke before 2000, including the SPAF Trials. The SPAF studies were conducted at centers nationwide between 1987 and 1999 with neurologists Robert Hart, M.D., and David Sherman, M.D., of the Health Science Center as the principal investigators. The Lancet report, which inflated trial costs to 2004 U.S. dollars based on a medical services component of the U.S. Consumer Price Index, projected that the SPAF Trials, funded at $42.7 million in 2004 dollars, will show a 3,000 percent return on investment by 2010.
Atrial fibrillation, a quivering of the heart’s upper-right chamber that results in rapid, irregular pulse, may give rise to blood clots that block arteries and cause ischemic stroke. More than 2.2 million Americans have been diagnosed with atrial fibrillation and are at increased risk for ischemic stroke, the type of stroke resulting from lack of oxygen to the brain.
“During the first phase of SPAF, we showed that daily administrations of warfarin, an anti-clot agent, reduced the risk of ischemic stroke in atrial fibrillation patients by two-thirds,” Dr. Hart said. “We also showed that daily aspirin alone reduced the risk by 20 percent.”
SPAF enrolled 3,950 patient volunteers, including 350 from the San Antonio area. Most of the Hispanic participants were from San Antonio. “We can’t overemphasize the debt of gratitude we owe our volunteers,” Dr. Hart said. “We know how to prevent stroke in atrial fibrillation because of them. Their contributions helped not only themselves, but successive generations. This is an example of how people with a neurological disease can work together to conquer it.”
The SPAF Trials, which in San Antonio enrolled patients from clinics in the University Health System and the South Texas Veterans Health Care System, led to stratification of patients based on stroke risk and potential to benefit from therapy. Some patients, such as those with consistently high blood pressure, may not be able to take warfarin because of risk of bleeding.
Drs. Hart and Sherman thought up the SPAF study in 1985 in a lab at the Health Science Center. The institution was in its second decade, and Dr. Hart “wondered if two people in the ‘far hinterlands of medical research’ could get this off the ground. We did, and the success we had in leading the SPAF Trials directly contributed to our follow-up studies, called Secondary Prevention of Small Subcortical Strokes, or SPS3, under the direction of principal investigator Oscar Benavente, M.D. Atrial fibrillation is one cause of ischemic stroke, and in SPS3 we shifted to another cause, small subcortical strokes, which are equally frequent and occur at twice the national average in our community with its large Hispanic population.” The National Institute of Neurological Disorders and Stroke funded SPS3 at $37 million and the trial is now in 50 centers.
“Sometimes when research is being done and millions of dollars are being spent on it, people think it is an awfully high price to pay, but when you look at the benefits – and this analysis was done by an independent group – you can see the payback over the long haul,” Dr. Sherman said.
“Inclusion in the analysis indirectly points out that while there have been a number of atrial fibrillation studies for stroke prevention, it is becoming more the case that people consider the SPAF studies to be the most important ones,” Dr. Sherman added. “I believe the SPAF studies will go down in history as being the pivotal studies. It is gratifying that a homegrown study here in San Antonio is recognized around the world as the important one, and is the study they refer to consistently as the one that led the way in how to manage these patients.”
The authors of The Lancet article point out that for a variety of reasons, the analysis led to conservative estimates of the benefits of the clinical trials studied.
A stroke survivor story is featured in the HSC News’ After Hours feature section. Click here to learn more:www.uthscsa.edu/hscnews/singleformat.asp?newID=2029