cognitive impairment in older Blacks
By ERICKA P. THOMPSON
A five-year observational study conducted at the Indiana University School of Medicine and Regenstrief Institute found that one class of drugs that blocks stomach acid might be associated with cognitive impairment in older African-American adults.
According to the study, which was published in the August issue of the Journal of the American Geriatrics Society, long-term use of histamine2 receptor antagonists may cause 2.5 greater risk of showing signs of cognitive impairment for patients using these medications.
Dr. Malaz Boustani, lead author of the study, says he noticed as a physician treating older patients at Wishard Memorial Hospital after giving them medication to prevent stomach bleeding certain patients developed temporary confusion.
“I was interested to see if the confusion could be translated long term because of these medications,” he told the Recorder. “I wanted to know if patients took the medications for a long time, would they be at risk for developing a more permanent cognitive impairment like Alzheimer’s.”
The acid blockers, including ranitidine and famotidine, are among the most popular medications prescribed in the U.S. with more than 16 million dispensed in 2005. Several of these medications are also available over-the-counter and are sold under brand names such as Axid, Pepcid, Tagamet and Zantac. Each is used to treat ulcers, acid reflux and other gastrointestinal disorders.
The key part to the study is the effect the drugs may have on African-Americans.
The study included 1,558 cognitively normal African-Americans aged 65 and older. After controlling for other possible factors, nearly 18 percent exhibited signs of cognitive impairment.
“Taking these medications continuously appears to put older African-Americans at greater risk for the development of cognitive impairment,” said Boustani, who is also a professor at IU School of Medicine and a Regenstrief research scientist.
Boustani says he’s unsure why African-Americans are more at risk and that more study is needed.
“We want to do a clinical trial starting with patients who are at a high risk for developing Alzheimer’s and divide them into one group and make sure they don’t receive the medications,” he said. “We’re going to take another group who will take the medication and follow them for nearly five years and see if the percentage of those who develop the disease is much smaller than the group not exposed. That will be the strongest verdict.”
Boustani says such a study can take five to 10 years.