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By Serena McNiff<\/b>
HealthDay Reporter<\/i><\/p>\n
MONDAY, July 6, 2020 (HealthDay News)<\/p>\n
Millions of Americans take medication to keep their blood pressure<\/a> down. A new study suggests that two types of blood pressure<\/a> drugs<\/a> might do double-duty, keeping colon cancer<\/a> away, too.<\/p>\n Angiotensin converting enzyme inhibitors (often called ACE inhibitors<\/a>) and angiotensin II receptor blockers<\/a> (ARBs<\/a>) help lower blood pressure by relaxing and opening up narrowed blood vessels, allowing blood to flow freely.<\/p>\n Researchers analyzed the health records of almost 200,000 adult patients in Hong Kong from 2005 to 2013. Compared to nonusers of the drugs<\/a>, those who took ACE inhibitors<\/a> or ARBs<\/a> had a 22% lower risk of developing colon cancer<\/a> in the three years following a colonoscopy<\/a> that declared them cancer<\/a>-free, they found.<\/p>\n The researchers, from the University of Hong Kong, excluded all patients who had a prior history of colon cancer<\/a>.<\/p>\n The benefit was especially true for patients 55 or older, and those with a history of colon polyps<\/a> — potentially cancerous growths.<\/p>\n In the three years following a clean colonoscopy<\/a>, there is already low risk of developing colon cancer<\/a>. Still, study author Dr. Wai Leung, a professor of medicine at the University of Hong Kong, said that cancer<\/a> can develop during this period.<\/p>\n “We found that there’s a very strong, protective effect, particularly within that short period of time after a negative colonoscopy,” Leung explained.<\/p>\n But the protective effects only lasted for those first three years.<\/p>\n The results were published July 6 in the journal Hypertension<\/a><\/i>. They showed that the drugs do not reduce the risk of all colon cancer<\/a>, but are particularly beneficial in preventing colon cancer<\/a> that arrives soon after a colonoscopy.<\/p>\n Colon cancer is the third most common cancer and the second leading cause of cancer death worldwide.<\/p>\n If commonly prescribed drugs could be repurposed to prevent colon cancer, it would have a significant public health impact, said Dr. Raymond Townsend, director of the hypertension<\/a> program and a professor of medicine at the Hospital of the University of Pennsylvania.<\/p>\n Townsend said the results of this study are significant, especially since the researchers looked at such a large population.<\/p>\n “A 22% reduction is not trivial, so I think there’s a story here,” added Townsend, who had no role in the study.<\/p>\n The study also found that the longer you use the medications, the more likely you are to experience a benefit.<\/p>\n For every year that the patients took the drugs, the risk of developing colon cancer in the three years following a clear colonoscopy was lowered by 5%.<\/p>\n But Townsend emphasized that studies like this generate more questions than answers.<\/p>\n The population of people who take medications to lower their blood pressure are often older and have other risk factors for cancer.<\/p>\n As people age, their chances of developing high blood pressure<\/a> go up dramatically — as do their chances of developing cancer.<\/p>\n “You’ve got a population that is primed to develop the problem in the first place,” Townsend said.<\/p>\n Since the study looked at people in the real world, there are risk factors and variables that naturally affect the results.<\/p>\n “Is it the person, or is it the medication?” Townsend wondered.<\/p>\n And prior research has shown the opposite effect — that medications for high blood pressure<\/a> could cause cancer, instead of preventing it.<\/p>\n “Since 1976 or so, this issue of cancer in patients on blood pressure medicines has been in the literature repeatedly,” Townsend explained.<\/p>\n Based on how these blood pressure medications work, there is some reason to believe they could prevent cancer.<\/p>\n For cancers<\/a> to grow, they have to develop new blood vessels, and blood pressure medications may block the formation of these new vessels.<\/p>\n “It’s possible that these medications really cut off the blood supply of these tumors and prevent them from growing,” said Dr. Andrew Chan, a colon cancer specialist and professor at Harvard Medical School. He was not involved in the study.<\/p>\n However, the study cannot show a direct cause-and-effect relationship. And Chan added, “one study is not enough to sway clinical practice, and you really need to verify that you have similar associations in other studies.”<\/p>\n![\"MedicalNews\"](\"https:\/\/images.medicinenet.com\/images\/HealthDay\/healthday.png\")
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