A new research study finds that repeated use certain drugs for gastric reflux or peptic ulcers is linked to a higher risk for dementia among elderly patients in Germany.
The researchers looked at proton pump inhibitors (PPIs), a class that includes Prevacid (lansoprazole), manufactured by Novartis, Nexium (esomeprazole) and Prilosec (omeprazole), both made by AstraZeneca, Reuters Health reports.
The study’s senior author, Britta Haenisch of the German Center for Neurodegenerative Diseases in Bonn, says the study can provide only a statistical association between PPI prescriptions and dementia in the elderly, but it cannot prove that PPIs cause dementia. Haenisch told Reuters Health in an email that the researchers “focused on long-term regular PPI prescription for at least 18 months.” They reviewed medical records for more than 73,000 patients age 75 and older, most of them women, from 2004 through 2011. The researchers classified 2,950 patients as regular PPI users, meaning they had at least one prescription for one of the drugs every four or five months over an 18-month period. These drugs are also available in over-the-counter versions, but the researchers looked at prescription PPIs.
During the years examined in the study, 29,510 people developed dementia. Regular PPI users were 44 percent more likely to develop dementia than those who were not taking the drugs, according to Reuters Health. Haenisch noted that the authors could not know whether some of the study subjects were already at increased risk for dementia. The study was published online on February 15, 2016 in JAMA Neurology.
In an editorial accompanying the study results, Dr. Lewis H. Kuller of the University of Pittsburgh wrote that PPI use and dementia may both be influenced by similar risk factors. For example, Kuller wrote, in the Women’s Health Initiative, women who took PPIs were more often obese, had arthritis, and were generally in poorer health than others, and these factors may increase dementia risk. The drugs are known to carry other health risks, including increased risk of kidney disease and bone fractures, low magnesium levels, gastrointestinal infections, Clostridium difficile infection and pneumonia, Reuters Health reports.
“PPIs used for the treatment of gastroesophageal reflux disease and peptic ulcers work by reduction of gastric acid production,” Haenisch explains. “The underlying mechanism by which PPIs might influence cognition is yet to be determined.” Some of the drugs may cross the blood-brain barrier and interact with brain enzymes, or they may be associated with vitamin B12 deficiency, which may promote neurological damage, according to Haenisch. PPIs appear to effect levels of amyloid beta and tau, which are proteins associated with Alzheimer’s disease, CBS News reports.
Haenisch advises patients taking PPIs to follow their doctor’s instructions. “To evaluate cause and effect relationships between long-term PPI use and possible effects on cognition in the elderly randomized, prospective clinical trials are needed.”
Haenisch said doctors should be careful not to overprescribe PPIs, which has been reported. One study found that up to 70 percent of the PPI prescriptions were inappropriate for the patient, Reuters Health reports. A study published in January 2016 in JAMA Internal Medicine reported that 25 percent of long-term PPI users could stop taking the medication without suffering increased heartburn or acid reflux, according to CBS News.