A class of drugs used to treat heartburn, acid reflux and indigestion appears to be linked to an increased risk of long-term kidney damage, according to a new study. The research, published online Jan. 11 in JAMA Internal Medicine, suggests that proton pump inhibitors (PPIs) may lead to chronic kidney disease (CKD).
One of the most commonly prescribed medicines in the U.S., PPIs are used to reduce acid in the stomach. Though the study does not prove the drugs cause kidney disease, it does support previous studies linked to this side-effect. Given that millions of people a year take prescription or over-the-counter drugs such as Prilosec, Prevacid, Nexium or Zegerid, the association between the medicines and CKD is of great concern.
“There appears to be mounting observational evidence that PPIs – historically a class thought to be extremely safe – have some adverse side-effects,” lead author Morgan Grams, MD, PhD, an epidemiologist at the Johns Hopkins Bloomberg School of Public Health, told Reuters in an email. “Given the widespread use of PPIs, even relatively rare adverse effects can impact large numbers of people.”
For the study, Grams and her colleagues looked at two large data sets to determine if there is a connection between PPIs and kidney disease in the general population. One set involved 10,482 participants in the Atherosclerosis Risk in Communities (ARIC) study and the other 248,751 patients who were a part of the Geisinger Health System in Pennsylvania.
Among the 322 people in the ARIC group who used PPIs, the 10-year risk of chronic kidney disease was 11.8 percent, versus 8.5 percent for those who did not take PPIs. In the Geisinger group, the researchers found that over 10 years, the risk of CKD was 15.6 percent among PPI users, compared to 13.9 percent in non-PPI users.
The study also compared people who took the drugs once a day to those with those who took them twice a day. Their findings showed twice-a-day use was associated with a 46 percent increased risk of chronic kidney disease, versus a 15 percent increased risk in those who took one dose a day.
The researchers noted their study does not prove cause-and-effect, and that no one is sure how the drugs might damage the kidneys. Grams told HealthDay one theory holds that the medicines can cause a decline in magnesium levels, and a lack of this important mineral could damage the kidneys. There is also speculation that the kidneys become damaged over time if patients suffer repeated bouts of kidney inflammation caused by PPIs.
According to the study backgrounder, more than 15 million Americans used prescription PPIs in 2013. Findings suggest that up to 70 percent of these prescriptions are unwarranted and that 25 percent of long-term PPI users could stop taking the pills without developing symptoms.
In an editorial accompanying the study, Adam J. Schoenfeld, MD, and Deborah Grady, MD, of the University of Chicago, wrote: “A large number of patients are taking PPIs for no clear reason – often remote symptoms of dyspepsia or heartburn that have since resolved in these patients. PPIs should be stopped to determine if symptomatic treatment is needed,” they concluded.
The study authors, however, caution that study results don’t mean people should just stop using PPIs. They advise regular PPI users to consult with their doctor to determine if they really need them. Grams also noted that H2 blockers such as Pepcid, Tagamet or Zantac may offer a cheaper, safer alternative.