From NY Times, nyti.ms/1kwQHPF :
People who use certain acid-suppressing drugs for two years or longer are at increased risk of vitamin B12 deficiency, which can lead to anemia, neurological problems or dementia, researchers reported on Tuesday.
The drugs in question are called proton-pump inhibitors, or P.P.I.’s, and histamine 2 receptor antagonists, and they are available by prescription and over the counter under brand names like Prevacid, Prilosec and Nexium. Nearly 157 million prescriptions were written for P.P.I.’s alone last year.
“People who are taking these medications are more likely than the average person to be vitamin B12 deficient, and it’s a potentially serious problem,” said Dr. Douglas A. Corley, senior author of the new study, published in The Journal of the American Medical Association. “This raises the question of whether people taking these medications for long periods should be screened for vitamin B12 deficiency.”
Dr. Corley has received funding from Pfizer, which makes a P.P.I. called Protonix.
He and his colleagues at Kaiser Permanente in Oakland, Calif., examined the medical records of 25,956 adults who received vitamin B12 deficiency diagnoses between 1997 and 2011, comparing them with 184,199 patients without B12 deficiency during that period.
Patients who took P.P.I’s for more than two years were 65 percent more likely to have a vitamin B12 deficiency, the researchers found. Higher doses of P.P.I’s were more strongly associated with the vitamin deficiency, as well.
Twelve percent of patients deficient in vitamin B12 had used P.P.I.’s for two years or more, compared with 7.2 percent of control patients. The risk of deficiency was less pronounced among patients using H2RA’s long term: 4.2 percent, compared with 3.2 percent of nonusers.
The new study is the largest to date to demonstrate a link between taking acid suppressants and vitamin B12 deficiency across age groups. Earlier small studies focused primarily on the elderly.
Robert J. Valuck, a professor of pharmacy at the University of Colorado in Aurora, was surprised that the association in the new report was strongest in adults younger than age 30. “It’s not safe to assume vitamin B12 deficiency is only an issue in the elderly,” he said.
Bottomline: patients (not just elderly) on chronic PPIs may need to be tested for vitamin B12 deficiency.
Related blog entries:
Are we missing Vitamin B12? | gutsandgrowth