Proton pump inhibitors like Nexium, Prilosec, and PrevAcid may not be the best choice for breast cancer patients, according to a study that suggests the medications could worsen cognitive decline among survivors.
Many breast cancer patients already experience cognitive decline because of chemotherapy.
Previous research has also indicated that off-label use of proton pump inhibitors increases tumors’ responsiveness to chemo and protects the digestive system from the side effects of treatment. But it’s also known that these drugs could potentially cross the blood-brain barrier.
“I thought there could be a cognitive effect from taking PPIs, particularly in this population, because breast cancer survivors are already at risk for cognitive decline,” Annelise Madison, lead author of the study and a graduate student in clinical psychology, said in a press release issued by Ohio State University. “PPIs are over the counter and generally considered safe so there haven’t been many long-term trials, especially looking at cognitive outcomes, because nobody was really thinking that would be a downstream effect.”
The study — the first to examine the effects of proton pump inhibitors on breast cancer survivors — drew data from three clinical trials previously conducted at Ohio State that focused on fatigue, yoga intervention, and vaccine response in breast cancer patients and survivors. Participants in all three were required to report their use of prescription and over-the-counter medications. As part of routine data collection, they also rated any cognitive decline they experienced.
After controlling for depression or other illnesses, types of cancer treatment, age and education, the research team found that proton pump inhibitor use was a predictor of severe concentration and memory symptoms as well as lower quality of life related to impaired cognition.
“The severity of the cognitive problems reported by PPI users in this study was comparable to what patients undergoing chemotherapy had reported in a large observational study,” Madison noted. “PPI non-users also reported problems, but were definitely getting better. Based on what we’re seeing, we don’t know if PPI users might not be able to fully recover cognitively after chemotherapy. It’s an area for further investigation.”
However, it’s important to understand that the study only showed a correlation between proton pump inhibitor use and worsened cognitive decline among breast cancer survivors. According to Madison, a controlled clinical trial is still needed to prove any causal relationship.
The study is published online in the Journal of Cancer Survivorship.