Aiming to enhance the quality of stroke research, scientists from UCLA and the University of Pennsylvania analyzed controlled clinical trials from the past 50 years to determine where those studies went right and where they went wrong. Their research will appear in the June issue of Stroke, a publication of the American Heart Association.
The study's lead author, UCLA neurologist Dr. Chelsea Kidwell, describes the rise of controlled clinical trials over the latter half of the 20th century as a "scientific revolution that has reshaped modern medicine." But despite the enormous contributions such studies have made throughout the health sciences, the record of acute ischemic stroke trials, specifically, is "remarkably dismal," she said.
Of 85 promising drugs evaluated in trials over the past 50 years, only two were found beneficial: aspirin and the clot-buster known as tissue plasminogen activator. In addition, only three of the 178 trials analyzed in the study can be considered definitive by today's standards, reflecting frequent deficiencies in trial design and conduct.
"This gives us lessons we can use to design future trials," Kidwell said. "The need for topnotch research is critical, given that acute ischemic stroke is the third leading cause of death and the leading cause of adult disability in this country."
On a positive note, the quality of trials did improve substantially from the 1950s to the 1990s, Kidwell said. This indicates a growing sophistication of trial methodology and the realization that stroke must be treated very quickly, optimally within the first three to six hours, for medical interventions to be effective.
Here are some other trends identified in stroke studies over the past 50 years:
¬∑ The number of trials began to rise sharply in the mid-1960s
¬∑ The number of patients enrolled in trials increased dramatically over time, resulting in the creation of "megatrials" with tens of thousands of patients
¬∑ The proportion of trials funded by pharmaceutical companies increased steadily over the years
¬∑ The proportion of trials funded by government agencies and nonprofit groups decreased significantly
¬∑ The quality of trial design and reporting improved steadily
Participating in the study with Kidwell were Drs. Sidney Starkman and Jeffrey L. Saver from the UCLA Stroke Center, and Dr. David S. Liebeskind from the University of Pennsylvania. Their study is entitled "Trends in Acute Ischemic Stroke Trials Through the 20th Century."