Posted by March 12th, 2013
A study published in the March 11 JAMA-Internal Medicine suggests that 23 percent of over-75-year-olds have colonoscopies that may be “potentially inappropriate” according to national guidelines which include an upper age limit, as well as how often negative colonoscopies should be repeated.
In a retrospective population study, University of Texas researchers looked at billings for 100 percent of colonoscopies performed in Medicare beneficiaries in Texas who were aged 70 years and older who had a colonoscopy in 2008 or 2009. They also examined a nationwide sample of 5% of Medicare claims. Colonscopies were classified as “screening” if records (including claims from 2000 to 2009) did not indicate a diagnosis, or any visits for related symptoms in the previous 3 months.
Colonoscopies were labeled “potentially inappropriate” based on patient age over 75, or because the procedure was done less than 10 years after a previously negative colonoscopy. (The study population did not include anyone with a history of colon cancer, inflammatory bowel disease, colon resection, or whose procedure was performed during a hospital admission or emergency room visit.)
Among Texas residents, overall percentages of potentially unnecessary colonoscopies were:
- Age 70-75: 9.9 % of procedures done
- Ages 76-85: 38.8%
- Aged 86-plus: 24.9%.
There was wide variation in geographic areas of Texas, plus among individual doctors doing the screening procedures. The researchers did note that reasons for doing a colonoscopy in an individual patient cannot be assumed from billing information alone. (In fact only 15% of the claims included a screening code, although experts believe about two-thirds of colonoscopies are for routine screening.) The authors noted that there might be poor communication between a primary care doctor and the gastroenterologist; there could be financial incentives to do the procedure, or doctors might disagree with the national guidelines.
What are the guidelines?
In fact, there are different sets of guidelines. The U.S. Preventive Services Task Force (and recently, the American College of Physicians) specify age limits. The USPSTF says “For adults aged 76 to 85 years, there is moderate certainty that the net benefits of screening are small….and [for] adults older than age 85 years, there is moderate certainty that the benefits of screening do not outweigh the harms.”
However, joint guidelines developed by the American Cancer Society, the U.S. Multi-Society Task force on Colorectal Cancer, and the American College of Radiology do not include age limits. Part of the problem is lack of evidence: experts note that far too few population studies and clinical trials include those over age 75, even though about 30% of colorectal cancers are diagnosed in those 75 or older.
Increased risks might outweigh benefits for colonoscopy in those over age 75
Although the USPSTF urges caution in any screening over age 75, colonoscopy itself carries higher risks to elderly patients. Both this study’s authors and guideline developers urge extra caution—especially in unnecessary procedures—in the elderly who face higher risks from the preparation (fluid imbalance, start of a diarrhea/constipation cycle, dizziness or a rush to bathroom causing falls) plus effects of anesthesia in elderly patients.
Some over 75 will benefit
A caveat common among the experts: Among those who have never been screened, a screening colonoscopy might be indicated—especially if the older person is healthy, active, has few other diseases, and has an expected lifespan of more than 7 years.
Another study in the March 5 2013 Annals of Internal Medicine showed that in four HMOs, screening among people aged 55 to 85 did reduced the risk of advanced colorectal cancer by 70% in average-risk adults. However, the study showed that annual stool samples in this population (particularly when reminders and stool-sample kits were mailed to people’s homes) were as effective as colonoscopy.
What to do?
Probably the Centers of Disease Control & Prevention says it best: “The decision to be screened after age 75 should be made on an individual basis. If you are older than 75, ask your doctor if you should be screened.”
- All guidelines recommend a colonoscopy only every 10 years, unless you have symptoms, family history, or a previous removal of polyps or an adenoma. (In those cases, plan your “surveillance colonoscopy” with your doctor.)
- People aged 75 or older should pause to consider the need for a routine screening colonoscopy, especially if it’s less than 10 years since a previous negative colonoscopy. You can also consider other screening methods, such as a yearly stool sampling that is very effective at finding early cancer.
- Discussions about cancer (and other) preventive screening probably are best with your primary-care doctor, who knows all of your other health conditions, your general fitness level, etc.
- If you do have a colonoscopy, it’s best to get your own written record of the results, including number and type of any polyps. A common cause of getting too-frequent colonoscopies could be that a different doctor doesn’t know the results of your previous test(s).
As always, stay tuned for updates on both screening and colorectal cancer treatment in the elderly: As boomers age in, and hopefully more seniors are included in clinical and prevention studies, the science will get clearer.
For More information:
* CDC brief summary of guidelines
* Choosing Wisely: on colonoscopies
* Who is the USPSTF? “A Conversation with Dr. Virginia Moyer, Chair, U.S. Preventive Services Task Force, Nov. 27 2012 NCI Cancer Bulletin.
“Potentially Inappropriate Screening Colonoscopy in Medicare Patients,” Kristin M. Sheffield, Ph.D. et al, JAMA Internal Medicine, published online March 11, 2013
Other coverage of this study includes: “Seniors Getting Unnecessary Colonoscopies: Study,” Monday, Mar. 11 HealthDay News; and “Many Colonoscopies for Seniors May be Inappropriate,” Christian Nordqvist, 12 Mar. 2013 Medical News Today.
See previous Research News blogs, including the Feb. 14 2013 “Colorectal Cancer is (or Could Be) the Poster Child for Cancer Prevention” and
the May 16 2011 “Fight CRC Site Update: Some People Getting Colonoscopy Screening Too Often.”
Other recent articles about screening: “CRC Screening Tools—The Data and the Guidelines,” Linda Rabeneck, M.D., M.P.H., at January 2013 ASCO GI-Symposium; and “Screening Colonoscopy and Risk for Incident Late-Stage Colorectal Cancer Diagnosis in Average-Risk Adults,” March 5 Annals of Internal Medicine .