Colonoscopy by Primary Care Physicians Safe, Effective, Says Study
Physicians Need to Do More to Increase Screening Rates
Colonoscopies performed by primary care physicians have the level of safety and precision recommended by gastroenterology professional associations, according to a study published in the January/February issue of the Annals of Family Medicine.
That means primary care physicians could help meet the demand for endoscopic screening for colorectal cancer that gastroenterologists alone cannot fill, say FP experts.
"You don't have to be a gastroenterologist," said Michael Potter, M.D., a professor in the department of family and community medicine at the University of California, San Francisco, and a member of the National Colorectal Cancer Roundtable, of the study findings. "I was surprised by how much controversy this study generated. It's going over things we already know. What matters is the level of experience, not the specialty, of the endoscopist."
Potter was referring to the fact that the American College of Gastroenterology called the study's findings "potentially misleading" in a Jan. 13 media statement (2-page PDF; About PDFs) and asserted that "primary care physicians are more likely than gastroenterologists to miss colorectal cancer during colonoscopy."
Expanding on the idea that the procedure doesn't have to be performed by a gastroenterologist, Potter said nurse practitioners and physician assistants have performed colonoscopies -- under supervision -- in some practices, including gastroenterology practices.
"Instead of having a turf war, gastroenterologists should be working with primary care doctors to fill the need they can't meet without help," he said.
Potter also said that primary care doctors and gastroenterologists need improved communication when subspecialists do perform colonoscopic screenings.
"What you do with results is just as important as the procedure," he said. "Too often, results of tests do not get reported back to the primary care physician with evidence-based recommendations for follow-up. This is an area where primary care physicians and gastroenterologists should find common ground."
Michael Harper, M.D., a professor in the department of family medicine and comprehensive care and director of the family medicine residency at Louisiana State University Health Sciences Center, Shreveport, said primary care doctors can receive training in endoscopy through the National Procedures Institute. The institute is a joint venture of the AAFP, the Society of Teachers of Family Medicine and the Texas AFP.
"For physicians who already routinely perform flexible sigmoidoscopy, learning full colonoscopy will be easier," Harper said. "But the best way to address this issue is to increase endoscopy training in family medicine and internal medicine residencies."
Harper, who is president of the American Association of Primary Care Endoscopists, said patients in medically underserved areas, in particular, would benefit from more primary care physicians performing colonoscopy.
He said the American College of Gastroenterology's response to the Annals study relied heavily on three other studies, only one of which included a comparison of colonoscopy by primary care physicians to the same procedure by physicians in other specialties.
Harper said that according to that study, which was published in the January 2007 issue of Gastroenterology, a patient with colon cancer has a 3 percent chance of having cancer missed on a colonoscopy performed by a gastroenterologist and as much as a 6 percent chance of having cancer missed when the procedure is performed by a non-gastroenterologist.
"The difference between primary care and subspecialty care in missing a colon cancer on colonoscopy is insignificant when one considers the miss rates of other methods," Harper said.
According to another study cited by the gastroenterology association, this one published in January 1997 in the same journal, the chance of missing cancer is about 18 percent with single-contrast barium enema compared to about 5 percent with colonoscopy. Other studies, Harper said, have revealed a 22 percent to 32 percent miss rate with sigmoidoscopy and a more than 50 percent miss rate with fecal occult blood testing.
Thus, Harper said colonoscopy performed by a physician, regardless of specialty, "is far superior" to other methods.
However, he said, only about one-third of eligible patients receive screening.
"More impact on public health would occur if screening by any method was increased," he said. "If the American College of Gastroenterology wants to improve population health, its emphasis should be toward improving effectiveness of screening methods by all physicians, regardless of specialty."
"You don't have to be a gastroenterologist," said Michael Potter, M.D., a professor in the department of family and community medicine at the University of California, San Francisco, and a member of the National Colorectal Cancer Roundtable, of the study findings. "I was surprised by how much controversy this study generated. It's going over things we already know. What matters is the level of experience, not the specialty, of the endoscopist."
Potter was referring to the fact that the American College of Gastroenterology called the study's findings "potentially misleading" in a Jan. 13 media statement (2-page PDF; About PDFs) and asserted that "primary care physicians are more likely than gastroenterologists to miss colorectal cancer during colonoscopy."
Expanding on the idea that the procedure doesn't have to be performed by a gastroenterologist, Potter said nurse practitioners and physician assistants have performed colonoscopies -- under supervision -- in some practices, including gastroenterology practices.
"Instead of having a turf war, gastroenterologists should be working with primary care doctors to fill the need they can't meet without help," he said.
Potter also said that primary care doctors and gastroenterologists need improved communication when subspecialists do perform colonoscopic screenings.
"What you do with results is just as important as the procedure," he said. "Too often, results of tests do not get reported back to the primary care physician with evidence-based recommendations for follow-up. This is an area where primary care physicians and gastroenterologists should find common ground."
Michael Harper, M.D., a professor in the department of family medicine and comprehensive care and director of the family medicine residency at Louisiana State University Health Sciences Center, Shreveport, said primary care doctors can receive training in endoscopy through the National Procedures Institute. The institute is a joint venture of the AAFP, the Society of Teachers of Family Medicine and the Texas AFP.
"For physicians who already routinely perform flexible sigmoidoscopy, learning full colonoscopy will be easier," Harper said. "But the best way to address this issue is to increase endoscopy training in family medicine and internal medicine residencies."
Harper, who is president of the American Association of Primary Care Endoscopists, said patients in medically underserved areas, in particular, would benefit from more primary care physicians performing colonoscopy.
He said the American College of Gastroenterology's response to the Annals study relied heavily on three other studies, only one of which included a comparison of colonoscopy by primary care physicians to the same procedure by physicians in other specialties.
Harper said that according to that study, which was published in the January 2007 issue of Gastroenterology, a patient with colon cancer has a 3 percent chance of having cancer missed on a colonoscopy performed by a gastroenterologist and as much as a 6 percent chance of having cancer missed when the procedure is performed by a non-gastroenterologist.
"The difference between primary care and subspecialty care in missing a colon cancer on colonoscopy is insignificant when one considers the miss rates of other methods," Harper said.
According to another study cited by the gastroenterology association, this one published in January 1997 in the same journal, the chance of missing cancer is about 18 percent with single-contrast barium enema compared to about 5 percent with colonoscopy. Other studies, Harper said, have revealed a 22 percent to 32 percent miss rate with sigmoidoscopy and a more than 50 percent miss rate with fecal occult blood testing.
Thus, Harper said colonoscopy performed by a physician, regardless of specialty, "is far superior" to other methods.
However, he said, only about one-third of eligible patients receive screening.
"More impact on public health would occur if screening by any method was increased," he said. "If the American College of Gastroenterology wants to improve population health, its emphasis should be toward improving effectiveness of screening methods by all physicians, regardless of specialty."
FDA Warns Against Use of Oral Sodium Phosphates for Precolonoscopy Bowel Cleansing
The FDA has issued a product alert in response to reports of acute phosphate nephropathy associated with the use of oral sodium phosphate, or OSP, products for bowel cleansing prior to colonoscopy or other procedures.
The FDA alert specifically cited the prescription products Visicol and OsmoPrep, as well as some OTC laxatives.
The FDA said that patients who appear to have an increased risk of acute phosphate nephropathy after using OSPs include people age 55 or older; individuals who are hypovolemic or who have decreased intravascular volume; people who have baseline kidney disease, bowel obstruction or active colitis; and those who are using medications that affect renal perfusion or function (e.g., diuretics, ACE inhibitors, angiotensin receptor blockers and, possibly, nonsteroidal anti-inflammatory drugs).
However, the FDA alert noted, when such agents were used for bowel cleansing, serious adverse events have occurred in patients with no identifiable risk factors for acute phosphate nephropathy.
The FDA is requiring the manufacturers of Visicol and OsmoPrep to add boxed warnings to the labeling for those products.
The agency said OSPs will continue to be available as OTC laxatives. However, consumers should only use OSPs for bowel cleansing pursuant to a prescription from their doctor. The FDA also said it plans to amend the labeling conditions for OTC OSPs.
The FDA alert specifically cited the prescription products Visicol and OsmoPrep, as well as some OTC laxatives.
The FDA said that patients who appear to have an increased risk of acute phosphate nephropathy after using OSPs include people age 55 or older; individuals who are hypovolemic or who have decreased intravascular volume; people who have baseline kidney disease, bowel obstruction or active colitis; and those who are using medications that affect renal perfusion or function (e.g., diuretics, ACE inhibitors, angiotensin receptor blockers and, possibly, nonsteroidal anti-inflammatory drugs).
However, the FDA alert noted, when such agents were used for bowel cleansing, serious adverse events have occurred in patients with no identifiable risk factors for acute phosphate nephropathy.
The FDA is requiring the manufacturers of Visicol and OsmoPrep to add boxed warnings to the labeling for those products.
The agency said OSPs will continue to be available as OTC laxatives. However, consumers should only use OSPs for bowel cleansing pursuant to a prescription from their doctor. The FDA also said it plans to amend the labeling conditions for OTC OSPs.
A recent study published in Cancer Epidemiology Biomarkers & Prevention supports that view.
The study's authors concluded that physicians are not doing enough to ensure that patients are screened for colorectal cancer. More than half of patients ages 50-78 who visit their primary care physician at least four times a year, said the researchers, still did not get screened.
"I think that the main thing is developing systems so that it is easier for clinicians and their office staff to remember to offer (screening) when needed," Potter said.
Those methods, he said, could include use of electronic health record systems with point-of-care reminders or systems to allow other members of the medical staff to offer home stool tests using standing orders, helping arrange appointments for colonoscopy when needed, and making reminder phone calls or sending postcards to assist patients in completing tests that have been ordered.
Potter also recommends offering screening in combination with other regular health care activities. He was co-author of a study in the January/February Annals of Family Medicine that found offering fecal occult blood testing at influenza vaccination clinics increased screening rates.
"If a patient doesn't do the test that you recommend, it may be time to offer a different type of test," he said. "For example, many people who don't have time or who fear the invasiveness of colonoscopy are more than willing to do a yearly stool test. It's still the test that you can get done that is most important."
The study's authors concluded that physicians are not doing enough to ensure that patients are screened for colorectal cancer. More than half of patients ages 50-78 who visit their primary care physician at least four times a year, said the researchers, still did not get screened.
"I think that the main thing is developing systems so that it is easier for clinicians and their office staff to remember to offer (screening) when needed," Potter said.
Those methods, he said, could include use of electronic health record systems with point-of-care reminders or systems to allow other members of the medical staff to offer home stool tests using standing orders, helping arrange appointments for colonoscopy when needed, and making reminder phone calls or sending postcards to assist patients in completing tests that have been ordered.
Potter also recommends offering screening in combination with other regular health care activities. He was co-author of a study in the January/February Annals of Family Medicine that found offering fecal occult blood testing at influenza vaccination clinics increased screening rates.
"If a patient doesn't do the test that you recommend, it may be time to offer a different type of test," he said. "For example, many people who don't have time or who fear the invasiveness of colonoscopy are more than willing to do a yearly stool test. It's still the test that you can get done that is most important."
Related ANN Coverage
50 Proctored Colonoscopies Required
Surgical Guideline May Help FPs Seeking Privileges
(4/26/2006)
AAFP Counters Threat to Endoscopy Privileges
(12/13/2005)
More From AAFP
AAFP Response to American College of Gastroenterology Legal Opinion
Colonoscopy Position Paper
Policy on Colonoscopy Privileging
A-E: Recommendations for Clinical Preventive Services (see "Colorectal Cancer")
50 Proctored Colonoscopies Required
Surgical Guideline May Help FPs Seeking Privileges
(4/26/2006)
AAFP Counters Threat to Endoscopy Privileges
(12/13/2005)
More From AAFP
AAFP Response to American College of Gastroenterology Legal Opinion
Colonoscopy Position Paper
Policy on Colonoscopy Privileging
A-E: Recommendations for Clinical Preventive Services (see "Colorectal Cancer")
