By Deepthi Nishi Velamuri

Colorectal cancer (CRC) remains a serious public health issue in the U.S. that affects people from all walks of life, independent of race, gender, or age. The third most commonly diagnosed cancer in the U.S., an estimated 150,000 new cases and 53,000 deaths are attributed to CRC each year, highlighting the urgency for effective prevention and early detection strategies. [1]

Early and regular screening can improve detection rates and lead to better outcomes for CRC. However, there are significant disparities in the rates of CRC screening for some groups, such as medically underserved communities. Race and ethnicity, socioeconomic status, and access to healthcare services have a significant impact on CRC screening rates . 

During the annual Digestive Disease Week 2023 meeting,  several research studies were presented that identify interventions to improve CRC screening rates, specifically in medically underserved populations. The following interventions were identified in the systematic review to increase CRC screening rates among medically underserved populations:

  1. Multicomponent interventions: These interventions involved multiple elements, such as patient education, provider reminders, patient navigators, and mailed outreach. [2][3]
  2. Patient navigation: Interventions that included the use of patient navigators, who assist patients in navigating the healthcare system and overcoming barriers to screening, were effective in increasing screening rates. [3]
  3. Mailed stool-based kits with provider letters: Sending screening kits to patients by mail, along with a letter from their healthcare provider recommending the screening, was found to be a successful intervention. [3]

Multiple Elements to a Successful Screening Program

The study conducted by Shailavi Jain et al., [3] highlighted the impact of a multicomponent health system intervention to increase screening participation among patients with a family history of CRC. This intervention involved:

  • Electronic health record reminders to primary care providers
  • Reminders to patients to schedule a colonoscopy
  • Additional educational resources about familial CRC risk and the colonoscopy procedure 

The intervention increased colonoscopies ordered, scheduled, and completed among high-risk patients.

Another study focused on using patient-level structured data elements to optimize population-based CRC screening. The study utilized individualized health data, such as laboratory results and diagnosis codes, to identify patients with significant comorbidities who were unlikely to complete routine screening. This approach allowed for targeted screening efforts to be directed towards patients most likely to complete screening as intended by their primary care team. [4]

A meta-analysis examined the efficacy of an opt-out outreach method  to optimize screenings. [5] This approach involved giving patients the option to either opt-in or opt-out of receiving fecal immunochemical test (FIT) kits. The analysis showed that patients who were given the option to opt-out had a significantly higher FIT completion rate compared to those who were given the option to opt-in. 

Additionally, a quality improvement project evaluated the effectiveness of mailed reminders in increasing uptake of FIT. Mailed reminders were found to be an effective strategy in improving screening rates. [6]

Overall, these studies highlight the effectiveness of various interventions, including multicomponent approaches, patient navigation, mailed reminders, and opt-out outreach methods in increasing CRC screening rates among medically underserved populations and individuals with a family history of CRC. These interventions can inform the design of programs aimed at improving CRC screening in these populations.

References-

  1. American Cancer Society.
  2. Vella J., Patel, S, Bowman B., et al. Interventions to improve colorectal cancer screening among medically underserved populations: A systematic review. In: Digestive Disease Week 2023; May 6-9, 2023; Chicago, IL.
  3. Jain S, Galoosian A, Badiee J., et al. Impact of a multicomponent health system intervention to increase colorectal cancer screening participation in patients with a family history of colorectal cancer: A systematic review. In: Digestive Disease Week 2023; May 6-9, 2023; Chicago, IL.
  4. Corren R., et al. Flagging comorbidities using patient-level structured data elements to optimize population-based colorectal cancer screening: A systematic review. In: Digestive Disease Week 2023; May 6-9, 2023; Chicago, IL.
  5. Battepati D., et al. The efficacy of opt-out outreach method to optimize colorectal cancer screenings: A systematic review and meta-analysis.: A systematic review. In: Digestive Disease Week 2023; May 6-9, 2023; Chicago, IL.
  6. Ahmad Abu-Heija, Abdelnour D, et al. Effectiveness of mailed reminders in increasing uptake of fecal immunochemical testing for colorectal cancer screening: A quality improvement project.: A systematic review. In: Digestive Disease Week 2023; May 6-9, 2023; Chicago, IL.

 

Deepthi Nishi Velamuri is a Colorectal Cancer Prevention Intern with the Colon Cancer Foundation.

By Parker Lynch

Despite the current methods that exist for people to receive preventative screenings, colorectal cancer (CRC) screening rates remain below the 80% national goal. Since the utilization of the current testing methods are subpar among average-risk adults in America, researchers are testing the reliability of a blood-based test, which remains a preferable screening method for a variety of preventive tests in the general population. The hope is that a preferred screening method would improve screening rates for CRC among average-risk adults. 

Testing the Reliability and Validity of a Blood-Based Test

The ECLIPSE clinical trial evaluated the performance of a cell-free DNA blood-based CRC screening test. Individuals who were average-risk (those with no identifiable risk factors or abnormal predispositions to being diagnosed with CRC), 45 years of age or older, and presenting for colonoscopy screening were recruited from 265 U.S. clinical sites between October 2019 and September 2022. This population was diverse, which makes the findings generalizable:

  • 54% female
  • 7% Asian
  • 12% Black/African-American 
  • 79% white
  • 12% Hispanic/Latino 

Prior to their colonoscopy, participants provided whole blood samples. In doing so, researchers were able to compare the validity of the blood-based tests when compared to the actual results that were obtained from the colonoscopy procedures. 

The trial found that the blood test was:

  • 90% sensitive to detecting Stage I – III CRC
  • 100% sensitive to detecting Stage IV CRC
  • 90% specific

In another study, researchers retrospectively analyzed blood samples of 425 individuals who were to undergo a colonoscopy. The blood samples were tested for specific genetic and epigenetic changes and these were then correlated with the individual’s colonoscopy results. 

Here’s a fun video that explains what genetic and epigenetic changes are.

The test was found to be:

  • 82% sensitive for CRC
  • 90% specific

Overall, the researchers concluded that this test provides clinically meaningful performance and has utility for CRC screening.  A limitation of the specificity/sensitivity study was the utilization of an older version of the assay. However, should the results of up-to-date versions of the assay remain statistically significant, blood-based screening could be a very effective and preferable CRC screening method. 

Both these studies demonstrate the effectiveness of blood-based tests, which will hopefully improve the rate at which people get their preventative testing for CRC.

 

Parker Lynch is a Colorectal Cancer Prevention Intern with the Colon Cancer Foundation.

 

Photo credit: Photo by Testalize.me on Unsplash  

Photo credit: Arek Adeoye on Unsplash

After publishing a blog post on Sarah Keadle, Ph.D.’s latest published research, entitled “Impact of Moderate-Vigorous Physical Activity Trajectories on Colon Cancer Risk over the Adult Life Course”, I had the opportunity to sit down and chat with her about these findings and what they mean for colorectal cancer prevention. Dr. Keadle holds graduate degrees from the University of Massachusetts Amherst and Harvard University and is Associate Professor, California Polytechnic State University, San Luis Obispo. 

CCF: What were your greatest revelations over the course of this research?

Dr. Keadle: The take home message is pretty consistent with what we see in terms of other physical activity in relation to other disease outcomes, that even moderate amounts of activity are really important. 

In our sample, the moderate group was doing about two hours a week of predominantly walking-type activities, and they were protected. Those who maintain that amount of activity over the life course were protected against colon cancer risk. 

Those who did a little more activity had a little bit more protection, so they were classified as the “high” active. These individuals were exceeding our current physical activity recommendations consistently throughout the life course relative to those who stayed inactive.

But then I think what’s also interesting is that there’s this: we were able to look at those who increased and those who decreased activity over time. The group who decreased their activity, the “early decreasers”, were in the 30-35- age group and had the worst risk—their risk of developing colon cancer was greater than those who stayed inactive. 

And those who were not active when younger but started increasing their activity by age 30, there was evidence suggesting that they may also be protected from developing colon cancer. So if you’re targeting middle-aged adults, it’s not too late to start being active. Even a moderate amount of activity appears to be protective.

                     Sarah Keadle, Ph.D.

CCF: What kinds of exercises would you recommend for people who have mobility issues and are limited in what activities they can do? 

Dr. Keadle: Much  of the data show that walking is the most accessible, and the best form of activity for most adults. For those with more serious limitations that don’t allow them to walk, there could be adaptations such as specialized gym equipment. But I think, for the vast majority of adults, if they feel intimidated by the thought of exercising or running, or exercise that will place a lot of stress on joints, or cause them pain or discomfort, you don’t have to be out of breath and sweating and uncomfortable to get the benefits of physical activity. There’s a lot of evidence that just moderate walking is one of the best forms of activity. 

As part of the 2018 physical activity guidelines, [the Department of Health and Human Services] launched the Move Your Way campaign to try to promote physical activity at the community level, and I know that they have several resources on how to adapt things to people with different types of disabilities. 

CCF: My next question is more about structural barriers to exercise. So people who are living in locations where they don’t really have access to safe parks and gyms. What would you recommend?

Dr. Keadle: That is a huge issue. I think one benefit potentially of COVID is that there are more online resources for at home activities and workouts that are targeted at different levels and different types of activities. So I think that’s a good place to start. It’s also important to spread the message of just getting up and moving, trying to not sit for really long periods of time. Get up and move around your house or try to find places that feel safe, even if it’s the backyard. To get outside and try to break up and get steps in is definitely beneficial. 

CCF: Those are great tips. And what kinds of policy changes, if any do you think would help alleviate some of those barriers?

Dr. Keadle: That’s a great question. So the CDC [Centers for Disease Control and Prevention] has launched a campaign around safe streets and complete streets programs to try to make it so that our streets are safer for people to bike, walk, and drive. I’m teaching a class right now on physical activity and public health to undergraduate students, and they ask, “We’ve reviewed the evidence. Physical activity is good. But, what are we actually doing about it?” And I think that the Move Your Way campaign has done a good job of trying to get more community level buy-in. And that’s one of the big things that needs to happen to kind of shift the culture around physical activity. 

I think that there are things happening, but it’s definitely slow, and I think aligning physical activity with other goals is important. So, if you have an activity program in a park that may make the park safer and in the long run, you also have the benefit of increasing physical activity. 

However, there’s not a lot of money in promoting physical activity. There’s no lobby group that will make money off of promoting physical activity. So, hopefully, we can capitalize on other initiatives and try to convince people to create those types of structural changes. Access to green space is a big predictor of physical activity, so making safe parks available is one of the biggest policy level changes I can think of. 

CCF: Yeah, well thank you so much. Lastly, I just want to say congrats again on the publication of the study back in January. That’s amazing. And what is next for you and your team in terms of either just exercise research or colon cancer research? 

Dr. Keadle: I have an intervention study for which we’re randomizing our last subject. The study is looking at a strategy to try to reduce screen time in adults. There’s a fair amount of data on kids, but we don’t know a lot about adults in terms of what’s the best way to get people off their screens. And if they do, are they more physically active? And what else changes along with that? 

I’m also continuing to do a few epidemiological studies about the interaction between physical activity and sedentary time and how that relates to health. It’s interesting because people cite lack of time as their biggest barrier to being physically inactive—it is the most commonly cited barrier. But then, if you look at the actual time-use data, people are spending like four hours a day on their phones.

So it’s perceived, and I get it that not everybody wants to exercise in the evening. But that’s where that messaging of “move more, sit less, break up sedentary time” and trying to make it approachable and just beginning to get it into people’s lifestyle is going to end up being a huge change in the long run. 

CCF: Absolutely, yeah. And maybe even communicating those messages through social media.

Dr. Keadle: Right. We have an app for our study, which feels ironic, that we’re trying to reduce screen time by creating an app that tracks their screen time and gives them feedback and strategies, but it lets [participants] set limits and things like that.

 

Emma Edwards is a Colorectal Cancer Prevention Intern with the Colon Cancer Foundation.

Welcome back to our ongoing series exploring the intricate relationship between colorectal cancer (CRC) and various health conditions. Our previous post uncovered the association between CRC and diabetes mellitus. Today, we embark on a new journey as we unravel the intriguing connection between cardiovascular disease and CRC. Through uncovering the latest research, we aim to shed light on shared risk factors and significant findings that emphasize the importance of addressing both these conditions. 

Shared Risk Factors Identified

A meta-analysis of 84 studies involving over 52 million participants has unveiled a clear association between cardiovascular disease and CRC. The analysis confirmed that individuals harboring risk factors for cardiovascular diseases, such as obesity, high body-mass index, diabetes, and smoking, face an increased likelihood of developing CRC. These shared risk factors act as crucial indicators of potential health complications. 

Intriguingly, the same study revealed a compelling insight: individuals who are obese and exhibit at least one metabolic abnormality, such as hyperglycemia, dyslipidemia, or hypertension, face a 31% higher risk of being diagnosed with CRC. This underscores the significance of managing weight and addressing metabolic health concerns as part of a comprehensive approach to reducing the risk of developing both cardiovascular disease and CRC. 

A study conducted in Taiwan involving a substantial cohort of over 94,000 patients delved into the relationship between cardiovascular disease and CRC prognosis. The findings demonstrated that individuals diagnosed with CRC are more prone to developing cardiovascular disease, particularly coronary heart disease, within the first three years following their CRC diagnosis. This highlights the need for comprehensive health management strategies encompassing cancer treatment and cardiovascular health for CRC patients. 

Uninsured and the Risk of CRC, Cardiovascular Disease 

In a noteworthy cohort study published in June 2022, researchers examined over 197,000 cases of CRC from the SEER database to study the prognosis of CRC patients. They assessed mortality trends due to cardiovascular disease and identified risk factors to develop a predictive model for cardiovascular disease outcomes in this population. The study unveiled a significant risk factor: lack of insurance coverage. It was found that CRC patients without insurance faced a higher likelihood of cardiovascular death than those with health coverage. These findings emphasize the need for further exploration of the link between social determinants of health and health outcomes. 

As we conclude our exploration of the connection between cardiovascular disease and CRC, it becomes increasingly evident that these two conditions share risk factors and impact each other’s prognosis. This knowledge encourages a holistic approach to

healthcare that prioritizes overall well-being and seeks to achieve optimal health outcomes for individuals facing these conditions. By addressing common risk factors, focusing on metabolic health, and implementing comprehensive healthcare strategies, we can strive to minimize the impact of both cardiovascular disease and CRC.

 

Emma Edwards is a Colorectal Cancer Prevention Intern with the Colon Cancer Foundation.

Update on June 2nd, 2023: Following an outcry from physician groups and patient advocacy groups, UnitedHealthcare (UHC) has slightly modified their policy. Gastroenterologists will now be required to submit an advance notification to UHC before conducting diagnostic or surveillance colonoscopy procedures. Under the revised policy, care will not be denied, so patients will not face out-of-pocket costs. However, physician groups remain skeptical.

 

Individuals who are covered under UnitedHealthcare’s commercial insurance will now require prior authorization for a colonoscopy. This policy, which goes live on June 1, 2023, does not apply to screening colonoscopy, which is conducted in individuals (45-74 years) at average risk who are healthy and do not display any gastrointestinal symptoms.

To understand the prior authorization process, read more here.

Procedures that will require prior authorization include:

  • Diagnostic colonoscopies: conducted in those who have a greater risk of colorectal cancer. This would include individuals with abnormal gastrointestinal symptoms, polyps in the colon, or a positive screening test.
  • Surveillance colonoscopies: conducted in those who have a personal history of colorectal polyps or cancer.

Will This Create Access Barriers for Patients?

Physicians are concerned that this procedural change will impact both patients and healthcare staff. Prior authorization adds a layer of administrative burden for clinics and hospitals. More importantly, gastroenterologists and oncologists are concerned that patients may face unnecessary delays in diagnostic procedures, which can potentially affect disease outcome.

Folasade May, M.D., Ph.D., M.Phil., expressed her concerns with long wait times—maybe even weeks or months—for the approval to come through. For patients with aggressive disease, being left undiagnosed while waiting for insurance approval could mean advanced stage cancer, which is usually difficult to treat.

Colonoscopy procedures can be expensive if paid for out of pocket. The procedure alone can cost on average $2,125; this can increase to an average of $2,543 with the added costs of anesthesia, pathology, and bowel preparation.

 

Surabhi Dangi-Garimella, Ph.D. is a Scientific Consultant with the Colon Cancer Foundation.

As colorectal cancer (CRC) rates rise globally, especially in the early-onset population, identifying high-level risk factors for developing this disease becomes ever more critical. The link between diabetes and the incidence of colon and rectal cancers was discovered in 1998 and has been well-established since then, as many trials have uncovered the strength of the association between these two diagnoses. 

In 2013, a meta-analysis of 26 observational studies among more than 200,000 patients assessed the relationship between CRC and all-cause mortality (death due to any cause), cancer-specific mortality, and disease-free survival. Interestingly, diabetes was found associated with poorer outcomes for all three categories. A key finding from this study: individuals who have diabetes and CRC have a 17% increased risk of death due to any cause.

A 2017 article on the epidemiology of the association between diabetes and CRC delved into the potential molecular mechanisms of this association and the therapeutic implications of treating both diseases, and found that: 

  • Diabetes mellitus and CRC have many overlapping risk factors
  • Hyperinsulinemia, hyperglycemia, and hyperlipidemia may all play a role in the development of these dual diagnoses
  • Environmental and genetic risk factors may also play a role
  • Promising therapies for treating a dual diagnosis are statins, ACE inhibitors, anti-fibrotic agents, among others

A study among 2023 individuals evaluated the association between type 2 diabetes risk, cholesterol levels, triglyceride levels, and CRC. Additionally, the study assessed the association between Lynch syndrome—which results from a genetic mutation that can lead to CRC—and these other variables, and found that:

  • Individuals with Lynch syndrome, type 2 diabetes, and elevated cholesterol levels had an increased risk of CRC
  • High triglyceride levels in those with Lynch syndrome did not increase CRC risk 
  • Hyperinsulinemia and hyperglycemia in diabetic patients may increase the risk of CRC

A more recent study looked at the clinical and therapeutic implications of diabetes treatment and CRC risk. They found that while not always the case, these drugs often reduced the risk of dual diagnosis. Newer therapies, such as anticancer drugs that target IGF-1R and RAGE receptors (receptors for advanced glycation end products), may also help prevent and treat diabetes-induced CRC. 

It will be essential for future research to continue to explore the mechanisms behind these two diseases and to collaborate to create effective treatments for individuals experiencing dual diagnoses.

 

Emma Edwards is a Colorectal Cancer Prevention Intern with the Colon Cancer Foundation.

Millions of Americans risk losing free preventive care after a Texas judge ruled against the Affordable Care Act’s (ACA) preventive services requirement. This could potentially derail the gradual uptick in screening rates among 45-49-year-old Americans–the age group that was recently asked to start screening for colorectal cancer (CRC).

ACA requires insurers to offer full coverage of preventive services upon recommendation of the U.S. Preventive Services Task Force (USPSTF), the Advisory Committee on Immunization Practices, or the Health Resources and Services Administration. This means that enrollees do not have to pay anything out of pocket for those preventive services. However, Texas federal judge Reed O’Connor ruled that the USPSTF is an independent panel of volunteers who are not officers of the U.S. government, and therefore, they are not qualified to determine which preventive services should be free. 

The ruling applies explicitly to new and updated recommendations by the USPSTF since the ACA was established in March 2010. If it stands, additions and revisions to USPSTF recommendations made after March 2010 may be subject to out-of-pocket costs. These could include lung cancer screenings, medications to lower the risk of breast cancer for high-risk women, preexposure prophylaxis (PrEP) for HIV prevention, and statin use for heart disease prevention, among other recommendations. 

screening coverage

 

ACA and Colorectal Cancer Screening

CRC is a leading cause of cancer-related deaths in the U.S., and its incidence among individuals younger than 50 is rising. For the longest time, average-risk adults were asked to start preventive screening for CRC at 50 years and continue till 74 years. In 2021, the USPSTF expanded its recommendation and lowered the screening age to include adults ages 45 to 49. It is this 45-49 age group that may potentially begin to face cost barriers to CRC screening if Judge O’Connor’s ruling stands.

The ruling does not immediately invalidate the complete coverage of preventive services under the ACA; however, millions will soon be required to pay for certain preventative care services, which could impact screening rates. Medically underserved communities that experience significant healthcare inequities, including access to preventive screening for CRC, could face additional barriers to CRC screening and disparities in CRC healthcare outcomes.

 

Sahar Alam is a Colorectal Cancer Prevention Intern with the Colon Cancer Foundation.

Health disparities are present in a multitude of different health issues and drive inequity among populations. These populations can be defined by factors like race, income, gender, or even geographic location. Improving access to colorectal cancer screening involves addressing these populations. Researchers can utilize data to identify geographic disparities, but understanding racial disparities becomes more complicated due to sociodemographic and cultural considerations. Yet, scientists at the Memorial Sloan Kettering Cancer Center (MSKCC) may have discovered reasons for these disparities on a microscopic level.

MSKCC researchers analyzed DNA sequencing data of over 4,000 patients at the hospital over the course of 8 years and compared it to ancestry information. They found that patients with African ancestry had shorter median survival post-diagnosis, had less accurately predicted outcomes, and were less likely to have the genetic mutations needed to be considered for immunotherapy. Overall survival  for the African ancestry group was only 45.7 months post-diagnosis compared to 67.1 months for the European ancestry group.

Mutations in the adenomatous polyposis (APC) gene, which is a known tumor suppressor, are associated with better CRC outcomes. However, this mutation appeared to make no difference in survival for Black patients while improving survival rates among European, East Asian, and South Asian CRC patients.

Disparity in Treatment Response

When it came to treatment, the African ancestry group had less genetic markers for effective immunotherapy treatment as defined by the FDA. While the European ancestry group had a 20.4% qualification rate, the African ancestry group had only 13.5%. Even compared to those who did not qualify for immunotherapy treatments based on FDA guidelines, those with African ancestry still experienced less actionable genetic alterations than the European group (5.6% and 11.2% respectively). Researchers propose that this may be due to fewer BRAF V600E mutations in the African ancestry group. Patients who carry this mutation typically respond well to certain targeted treatments.

A limitation of this study is its exclusion of environmental and lifestyle factors that are important in CRC outcomes.

Addressing health disparities in screening and treatment benefits researchers and community efforts by identifying how and where to implement interventions. This study suggests that these large-scale issues may have solutions hidden within the population of interest itself.

 

Kaylinn Escobar is a Colorectal Cancer Prevention Intern with the Colon Cancer Foundation.

The applications of artificial intelligence (AI) goes beyond social media: scientists have found that it can be used to help physicians identify adenomas during screening. In Singapore, scientists affiliated with the Lee Kong Chian School of Medicine and Sengkang General Hospital evaluated the one year performance of AI colonoscopy and its impact on colorectal cancer (CRC) screening.

Adenoma Detection Rate (ADR) is the ratio of the number of colonoscopies that detect an adenoma to the total number of colonoscopies performed. Adenoma Detected Per Colonoscopy (ADPC) is the average number of adenomas detected per colonoscopy performed. These measures were used to determine the effectiveness of this emerging tool. This is not a new concept, however. Computer-aided detection (CADe) has previously been shown to  improve ADPC rate by 22%. More information regarding this previous study can be found here

AI Adds Value and Is Cost-Effective

Using a database of colonoscopy images, the GI Genius™ Intelligent Endoscopy Module is able to identify lesions that are potential polyps. The researchers recognize that there is a learning curve for providers to utilize the technology and there may be fatigue associated with using the technology for too long. Another risk involved is a longer procedural time due to the need for analyzing the results.

In order to determine if the benefits outweigh the costs, researchers used a prospective cohort study with CADe colonoscopies and traditional ones. They measured the polyp detection rate (PDR) which was the ratio of polyp-detected colonoscopies to the total number performed. Once these polyps were assessed in a lab via polypectomy, the ADR and ADPC rates were calculated.

Out of 843 CADe colonoscopies, the AI registered 1,392 hits with 71% of polypectomies being adenomatous. In the CADe group, the PDR was 45.6%, the ADR was 32.4%, and the ADPC was 2.08. Additionally, the mean procedural time for AI-aided colonoscopies and non-AI aided colonoscopies were not statistically significant, with the former taking an average of 19.9 minutes and the latter, 19.7 minutes.

Considering the cost of using AI assistance, the polypectomy rates increased revenue by more than $ US100,000 over the course of one year of AI-usage. This covered the subscription cost of the technology with $20,000 remaining. The study maintained that the AI-aided technology improved both ADR and PDR. Endoscopists also did not ignore the device prompts, indicating “adoption fatigue” was not an issue in this population. 

Leveraging technology to improve CRC screenings ranges from social media advocacy to using AI in screening. As we look to the future of screening, technology may be a solution to improve CRC detection rates and decrease morbidity.

 

Kaylinn Escobar is a Colorectal Cancer Prevention Intern with the Colon Cancer Foundation.

The benefits of exercise for overall health and disease prevention are well known. While research overwhelmingly points to physical activity as a protective factor against colorectal cancer, more research is necessary to delineate how the timing of physical activity during one’s life impacts the risk of developing colon cancer. In a recently published study, researchers examined the differences in colon cancer incidence in relation to levels of physical activity at different stages of life. 

Researchers conducted a baseline survey in 1995 and 1996 of adult men and women to measure exposures to moderate-to-vigorous physical activity (MVPA) and several other lifestyle-related factors among nearly 300,000 adults (50-71 years). Study follow-ups ceased in 2011 or following any diagnosis of colon cancer or death. 

In the primary exposure assessment, participants were asked to report and quantify MVPA they had participated in at various stages of their life: at ages 15-18, 19-29, 30-35, and in the previous decade. MVPA levels were measured by time:

  • Rarely or none
  • Less than 1 hour a week
  • 1-3 hours a week
  • 4-7 hours a week
  • Greater than 7 hours per week 

Pattern Recognition and Impact on Colon Cancer Risk

Researchers identified specific patterns of MVPA:

  • Maintaining the same general level of physical activity throughout the life course (whether low, moderate, or high levels of MVPA) 
  • Raising levels of physical activity during the life course, either earlier or later in life (increasers) 
  • Reducing the amount of MVPA over time, either earlier or later in life (decreasers) 

Several key findings emerged from these patterns: 

  • Participants who maintained high MVPA levels throughout their life had a 15% lower risk of colon cancer than those who maintained low MVPA levels throughout their life
  • Participants who increased MVPA levels at a younger age had a 10% reduced risk of colon cancer, and participants who increased MVPA levels at an older age had an 8% reduced risk of colon cancer
  • Decreasing MVPA levels during the life course resulted in a 12% higher risk of colon cancer incidence when compared with individuals who maintained low MVPA levels throughout their life

These findings suggest that individuals who consistently engage in MVPA throughout their life and those who increase MVPA levels during their life have a lower risk of being diagnosed with colon cancer. They provide hope to individuals who may begin their fitness journey later in life. 

Emma Edwards is a Colorectal Cancer Prevention Intern with the Colon Cancer Foundation.