New research published by Keith et al in BMC Cancer showed that angiotensin blockers—commonly prescribed to treat high blood pressure—may also impact survival in patients with pancreatic cancer. The results are from the largest population-based study of this question and suggest that a broader, prospective clinical trial may be warranted to confirm the results and potentially change clinical practice.
“These medications for hypertension do not have a lot of side effects—far fewer than chemotherapy, for example—and yet our data suggest that they might extend life in patients with pancreatic cancer,” said first study author Scott W. Keith, PhD, Associate Professor of Biostatistics at Thomas Jefferson University. “Clinical studies will be required to determine just how much these approved and inexpensive therapies can extend life, and our data make a strong case for investing in further research.”
Earlier research in animals suggested that RAS-type therapies (which include angiotensin II receptor blockers such as valsartan and losartan) and angiotensin I converting enzyme inhibitors (which include benazepril, ramipril, or lisinopril) might slow pancreatic cancer growth. Several small clinical trials suggested the same effect, although the numbers of patients in those studies were too small to draw broad conclusions. These medications interact with the angiotensin system, which is normally responsible for narrowing blood vessels, but have also been shown to interact with cancer-growth pathways.
Data Analysis
Researchers were able to examine data on 3.7 million adults living in a region of Northern Italy because of the availability of a comprehensive, population-based longitudinal health-care database from a public health-care system. Their analysis is the largest retrospective study to look at survival in patients with pancreatic cancer as it relates to blood pressure medication usage.
A total of 8,158 patients with pancreatic cancer were identified between 2003 and 2011 from this region. The health-care records from the database allowed the researchers to look at a patient’s full medical reimbursement record over time and adjust comparison groups for age, sex, comorbidities, cancer severity at diagnosis, cancer treatments, additional medication usage, and other variables. The team was able to compare patients who had taken certain classes of hypertension medication in a model to predict their mortality risk compared to otherwise similar patients who had not taken those hypertension medications.
The current results showed that the patients who took angiotensin II receptor blockers after their pancreatic cancer diagnosis had a 20% lower risk of mortality than those who did not, and similar angiotensin II receptor blocker use showed a 28% lower risk of mortality in the subgroup of patients who had been treated with surgery for their cancer. Those taking angiotensin I converting enzyme inhibitors experienced a 13% lower risk of mortality in the first 3 years after diagnosis compared with those who did not.
“We can’t predict reliably how much time these medications might extend life,” said study coauthor Vittorio Maio, PharmD, MS, MSPH. “A randomized clinical trial would be necessary to determine that benefit. But these data suggest that people with pancreatic cancer who are taking angiotensin II receptor blockers or angiotensin I converting enzyme inhibitors are living longer than those who aren’t. We urge academic institutions, cancer organizations, and the pharmaceutical industry to work together to establish a collaborative and well-resourced initiative to study the potential therapeutic effect of these antihypertensive medications on improving the care of patients with pancreatic cancer.”
Disclosure: This study was supported, in part, by an Institutional Research Grant from the American Cancer Society. For full disclosures of the study authors, visit bmccancer.biomedcentral.com.
