Hope for colon cancer epidemic as study finds common pill taken every day by millions could prevent disease
A large study shows that taking one aspirin a day can reduce the risk of colon cancer.
People who took the anti-inflammatory pill were a third less likely to develop the deadly disease in their lifetime than those who did not.
The drug worked even in the unhealthiest people: people who smoked, drank alcohol and were obese, putting them at greater risk of colon cancer.
Aspirin is thought to prevent colon cancer by blocking the formation of polyps that can develop into cancer and by reducing enzymes that have been shown to prevent tumor growth.
The team is confident that the results could lead to more doctors prescribing aspirin to prevent colon cancer, a disease that has reached epidemic proportions among young Americans.
Researchers at Mass General Brigham found that taking aspirin regularly reduced the risk of colorectal cancer by as much as 40 percent
The graph above shows the percentage of participants who ultimately developed colorectal cancer, including those who did and those who did not take aspirin.
Dr. Daniel Sikavi, lead author of the study and a gastroenterologist at Mass General Brigham, said: “Our results show that aspirin can proportionally reduce the greatly increased risk of colorectal cancer in people with multiple risk factors.”
‘In contrast, people with healthier lifestyles have a lower baseline risk of colorectal cancer. Therefore, their benefit from aspirin was still apparent, although less pronounced.’
The U.S. Preventive Services Task Force recommends that nearly all adults ages 50 to 59 (the group at highest risk for colon cancer) take a low-dose aspirin daily to help ward off the disease.
However, the nine-cent drug has been linked to dangerous internal bleeding, leading many doctors to stop prescribing it for regular use.
Colorectal cancer is one of the deadliest forms of the disease because its symptoms, such as rectal bleeding, are often mistaken for more benign problems, making prevention a priority. The disease is expected to kill more than 50,000 Americans this year, making it the second deadliest form of the disease after lung cancer.
For the most recent study, researchers at Mass General Brigham Hospital in Boston recruited 100,000 adults ages 15 to 18 and asked half of them to take a daily or weekly dose of aspirin.
The researchers recruited 107,655 men and women from the Nurses’ Health Study and Health Professionals Follow-Up Study and followed them for 30 years. The average age of the participants was 49.
The participants completed questionnaires about their lifestyle habits, such as diet, exercise, alcohol consumption and smoking.
Of those taking the drug, one group took either two regular-strength pills per week or one low-strength pill per day.
People who took aspirin regularly took either two or more standard pills per week (325 mg) or one low-dose pill (81 mg) per day.
Of people who regularly took aspirin, 1.98 percent developed colon cancer, compared with 2.95 percent of people who did not take the medication.
After adjusting for factors such as family history, this equates to a 33 percent lower risk of colorectal cancer for the aspirin group, the team found.
The benefits were even greater among those who reported having an unhealthy lifestyle: participants who took aspirin were 38 percent less likely to develop the disease than unhealthy participants who did not take aspirin.
However, people with healthier lifestyles had the least benefit from aspirin; the risk was seven percent lower than in people who did not take the pills.
According to the team, these results could lead doctors to prescribe ‘stronger’ aspirin to patients with unhealthy lifestyles.
The findings come amid a worrying rise in colorectal cancer among Americans under 50
Dr. Andrew Chan, senior co-author of the study and director of epidemiology at the Mass General Cancer Center, said, “Aspirin likely prevents colorectal cancer through multiple mechanisms.”
For example, the team believes that aspirin reduces the production of prostaglandins, pro-inflammatory proteins that have been shown to promote cancer cell growth.
In colon cancer tumors, an increased level of the enzyme COX-2 has been demonstrated. This enzyme produces pro-inflammatory proteins called prostaglandins.
These substances have been shown to promote the growth of colorectal cancer cells. Chronic inflammation is also a major risk factor for colorectal cancer.
Research has shown that aspirin also reduces the risk of colorectal adenomas, a type of polyp, or abnormal growth that can develop into cancerous colon tumors.
The new study has several limitations, including its focus on predominantly white healthcare professionals. The lifestyle factors data were also self-reported, which could lead to potential bias.
The study was published Thursday in JAMA Oncology.