An evaluation of noncancer medications used concomitantly with cancer therapies for patients with breast cancer showed that proton pump inhibitors specifically were associated with worse survival outcomes and with an increased risk of grade 3 or higher adverse events than other classes of therapy. Findings from the international evaluation were published in Cancer Medicine.
“Many women with breast cancer are also managing other chronic conditions such as high blood pressure, diabetes, or acid reflux, meaning they are often taking multiple drugs at once,” said lead study author Natansh D. Modi, PhD, of the College of Medicine and Public Health, Flinders Health and Medical Research Institute, Flinders University, and Lecturer in Pharmacy, Clinical and Health Sciences, University of South Australia, both in Adelaide, Australia. “Our results don’t suggest that people should stop taking their noncancer medicines, but it underlines how important it is for doctors to regularly review patient medications because people are living longer and managing multiple health issues.”
The study authors stressed that the findings do not indicate that such noncancer treatments need to be ceased, but that these concomitant medications need to be carefully managed in the setting of breast cancer care.
Methods
Researchers sought to understand the impact of commonly used noncancer medications on cancer outcomes and adverse events for patients with breast cancer who are concomitantly taking other medications at the time of undergoing cancer treatment.
They pooled participant data from 19 breast cancer clinical trials, which included a total of 23,211 patients, and conducted analyses of associations between noncancer medication use and overall survival, progression-free survival, and grade 3 or higher adverse events.
Key Findings
Concomitant proton pump inhibitor use showed the most significant impact on cancer outcomes, with poorer overall survival (hazard ratio [HR] = 1.19; 95% confidence interval [CI] = 1.08–1.30) and progression-free survival (HR = 1.11; 95% CI = 1.02–1.21) outcomes, as well as an increased risk for grade 3 or higher adverse events (odds ratio = 1.36; 95% CI = 1.21–1.53).
Corresponding senior author Ashley Hopkins, PhD, Associate Professor, College of Medicine and Public Health, Flinders University, noted that the findings regarding proton pump inhibitors in oncology settings warrant closer attention, but "it doesn’t mean that patients should cease their reflux medication without medical advice, but clinicians should be alert to potential risks and review whether [these agents] are genuinely needed."
Associations with higher risks for high-grade adverse events was noted with beta blockers, angiotensin-converting enzyme inhibitors/angiotensin II receptor blockers, and calcium channel blockers, but these medications demonstrated no impact on survival outcomes.
Statins and metformin showed no significant associations with survival or adverse event risks.
The study findings stress the need for a more holistic approach to breast cancer management, according to the study authors, that takes into account all medications a patient may be taking before prescribing new treatments. Additionally, the researchers said that follow-up studies are needed to understand the underlying biological reasons driving these associations and drug interactions, which would hopefully lead to clinical guidelines for safe co-prescriptions.
Disclosure: This research was supported by The Hospital Research Foundation, Tour de Cure, Cancer Council SA, the Flinders Foundation, Prostate Cancer Foundation and the National Health and Medical Research Council. For full disclosures of the study authors, visit onlinelibrary.wiley.com.
