The Truth About Colonoscopies, Pt 2
Know the Risks: Be Informed before Giving Consent
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As discussed in Part 1 of this series, colonoscopies are a major money-maker for the conventional medicine machine, generating at least $42B per year, year after year. And that’s without taking into consideration the cost complications. We also briefly talked about polyps – which rarely become cancerous. Doctors can charge more for the procedure if they remove a tiny benign polyp.
A conventional colonoscopy isn't simply a routine doctor's visit, but an ambulatory surgical procedure performed under anesthesia.
Like other ‘routine screenings for early detection’ – mammograms, pap smears, prostatic biopsies – colonoscopies have become synonymous with cancer prevention. Pause and think about that for a minute. The cancer industry has used its heavy-handed fear and propaganda machine to push tests that are costly, may not be necessary, are not benign and may not even lower the risk of cancer or death.
Sounds a bit like the big push for everyone to get Covid-19 shots doesn’t?
However, regarding screening colonoscopies, a new study was recently released by a group of brave European researchers. The internet and MSM was immediately on fire to discredit it and support the Party Line.
Eye On the Evidence
On October 9, 2022, The New England Journal of Medicine (NEJM) published a landmark study that dared to suggest colonoscopies are not as effective as previously thought. Colonoscopies were compared head-to-head against those who did not undergo cancer screening in a randomized trial that collected data over 10 years.
The large northern European trial that included nearly 85,000 people in a ten-year follow-up found an 18% reduction in colorectal cancer and a 50% reduction in risk of dying from colorectal cancer compared to an 88% death rate generally touted.
Study researcher Dr. Michael Bretthauer, a gastroenterologist at the University of Oslo in Norway, said he found the results “disappointing” but worthy of consideration. He went on to say, “We may have oversold the message for the last 10 years or so, and we have to wind it back a little.”
For decades, gastroenterologists have put colonoscopies on a pedestal, calling the procedure the “gold standard” for preventing colon cancer. In fact, clinicians believed that if everyone had this screening exam – a 66-inch rubber tube inserted in the rectum to view the colon – colorectal cancer would essentially become ‘extinct.’ But this new study (above), published in a peer-reviewed journal, brings to question colonoscopy’s dominance.
Routine Colonoscopies be Challenged
Colorectal screening is advocated for healthy, asymptomatic people; therefore, the risks from screening are important issues. As it turns out, more than 1,000 studies have reported serious complications after colonoscopy can occur.
Here’s an example:
A study published in 2006 in the Annals of Internal Medicine reviewed 35,945 charts of patients who had undergone colonoscopies within the Kaiser Permanente, Northern California (KPNC) health care system. This is what they found (whole numbers reported here for clarity):
Serious complications occurred in nearly 1 per 1000 exams without biopsy or polypectomy
Serious complications other than bleeding occurred in 7 per 1000 exams with biopsy or polypectomy
Bleeding occurred in nearly 5 per 1000 colonoscopies with biopsy
62% of bleeding episodes and 40% of all serious complications occurred following removal of polyps smaller than 10 mm
Perforation of the colon occurred more commonly with biopsy and occurred at a rate of almost 1 per 1000 exams
Ten deaths (1 confirmed to be causally related to colonoscopy) occurred within 30 days of the colonoscopy
What does this study mean in real numbers?
Given that 15,000,000 colonoscopies are performed each year in the US alone, the study points out:
Exam only, no biopsy/polypectomy: Up to 15,000 persons per year (1/1000) can have a serious complication – colon perforation, persistent pain/burning, persistent diarrhea, etc.
Exam with biopsy/polypectomy: Up to 105,000 persons per year (7/1000) can have a serious complication
75,000 persons per year (5/1000) may experience extended bleeding that may result in hospitalization, surgery and/or need for blood transfusion.
15,000 persons per year (1/1000) may have a perforated colon. Small perforations are less likely to cause immediate peritoneal irritation and the diagnosis can be delayed for as long as 30 days, leading to poor prognosis.
A person can even die from a colonoscopy. The reported death rate after colonoscopy is around 0.09%. That sounds like a tiny number, but when applied to 15,000,000 exams per year, up to 13,500 person per year can die as a result of a colonoscopy!
The complication and death rate numbers have remained remarkably stable over the years. In fact, a 2016 meta-analysis evaluated post-colonoscopy complications by querying PubMed, Embase and the Cochrane library “for population-based studies” that had complications that started within 30 days of the exam. scomplications that were found within 30 days of the exam. The quiry found 1,074 studies published between January 1, 2001 and December 1, 2015. Even though, perplexingly, only 21 studies met the ‘inclusion criteria’ for their worldwide review, the results are very similar to those published in the 2006 study (discussed above).
Most case reports are published to track serious complications, such as perforations or significant gastrointestinal bleeding occurring up to 4 weeks after the colonoscopy.
However, a 2010 study reviewed the risk of less serious complications. Researchers found that up to 33% of patients reported distressing gastrointestinal symptoms after the exam, including abdominal pain (10.5%), bloating (25%), self-limited gastrointestinal bleeding (3.8%), diarrhea (6.3%), and nausea (4.0%).
In a separate study, respiratory symptoms, including aspiration pneumonia, were found to rise approximately one week after colonoscopy. The study stated,
“As the rates of using deep sedation with anesthesia during colonoscopy have increased markedly in recent years, there is concern that respiratory complications may be an increasingly common event.”
Risks of Infection after Colonoscopy
Remember that each year in the United States, more than 15 million colonoscopies and 7 million upper-GI endoscopies are performed on generally healthy individuals. Both procedures are performed with an endoscope, a reusable optical instrument that can be cleaned but not sterilized. In 2018, a study evaluated the rates of infection after colonoscopy and upper GI exams done in ambulatory surgery centers across the US. What was discovered was that the rates of infection was “far higher than previously believed, and varied widely from one ambulatory surgery center to another.”
This study was the first to explore data on ambulatory surgery centers (ASC) and post-procedure infection.
Previously, post-endoscopic infection rates were thought to be around one event per million. The actual rate of infection within 7 days was found to be 1.1 per 1000 screening colonoscopy procedures; 1.6 per 1000 non-screening colonoscopy procedures (has a biopsy) and 3.0 per 1000 EDG procedures.
The rate of infections varied widely in different out-patient centers, ranged from 0 to 115 per 1000 procedures for screening colonoscopy; 0 to 132 for non-screening colonoscopy (polyp removed) and 0 to 62 for upper endoscopy.
Patients who’d been hospitalized before undergoing one of the procedures were at even greater risk of infection. Almost 45 in 1,000 patients who’d been hospitalized within 30 days prior to a screening colonoscopy returned to hospital or had an ER visit with an infection within a month. '
When these numbers are put in perspective of the total number of exams done per year (15,000,000), they are quite shocking:
0 to 115 infections per thousand colonoscopies ranges from 0 to 1,725,000
0 to 132 infections per thousand colonoscopies that remove a polyp ranges from 0 to 1,980,000
0 to 62 infections per thousand upper endoscopies ranges from 0 to 930,000
If hospitalized within 30 days of one of these procedures, up to 675,000 person can have an adverse event
That puts things into a different perspective, doesn’t it?
Perforations of the colon result in a leakage of stool into the abdominal cavity resulting in peritonitis, sepsis, and/or septic shock. In a 2019 study, 741 cases of colon perforation caused by colonoscopy were reviewed. Surgical interventions were employed in 75% of the patients, of these 15% were laparoscopic and 85% required laparotomy (opening the abdomen – a major surgery).
Management of colon perforations from a colonoscopy depends on the location of the puncture or tear, the severity of the infection (local pain vs systemic sepsis), and the general overall health of the patient. Some patients may be treated with broad-spectrum antibiotics and abdominal physical examinations every 3–6 hrs. The close watch is to monitor for increasing pain and fever, which would require emergency surgical clean out and repair. The overall complications from the surgery (operative morbidity) has been reported to be 21–44% with a mortality rate of 7–25%. Those at highest risk of perforation include patients with a known, large lesion, unremitting colitis, or an obstructing lesion.
The Skill of the Examiner
A topic almost never discussed is how skilled is your doctor? Afterall, we are told to get a colonoscopy to remove polyps that ‘just might’ become cancer. We assume that all doctors are adequately trained and experts in their field.
In 2010, an analysis of all colonoscopies performed between 1995 and 2008 were reviewed and compared against the experience of the endoscopist. This included a review of more than 25,000 procedures. This important study concluded:
“The relative risk (RR) ratio was highest for endoscopists performing less than 591 procedures per year. Colonoscopy carried out by a low-volume endoscopist was independently associated with bleeding and perforation.”
Colonoscopy is an invasive procedure, and a significant skill set is necessary to do it safely. A study from 2000 of colon perforations from reported,
“Although trainee endoscopists were involved in only 20% of the colonoscopies performed, eight (40%) perforations occurred while the training fellow was involved in the case.”
Recall that the primary reason doctors advocate for colonoscopies is to remove polyps. Patients assume “they got it!” when they are told a polyp has been removed.
Not so fast.
While the benefits of colonoscopy have long been promoted, its accuracy is rarely questioned.
In 2008, a study to assess the rate of missed adenomas was undertaken using a strict methodology to limit related to the technique used or to the expertise of the operator. A pooled miss rate for the first procedure was calculated as the total number of lesions missed by the first procedure divided by the total number of lesions found. A total of 286 patients completed both exams.
Among the 165 patients believed to be free of polyps after the first examination, 67 (41%) were found to have at least one polyp on the second examination whereas among the 191 patients believed to be free of adenomas on first colonoscopy, 27 (14%) were found to have at least one adenoma on the second procedure.
A similar study was done a few years later (2012) in Korea. Back-to-back colonoscopies by two different clinicians on the same day were performed on 149 patients. A total of 344 polyps (neoplastic and non-neoplastic polyps) were found, while 58 polyps (adenomatous and non-adenomatous) and 42 adenomatous polyps were missed, equating to a ‘miss rate’ of 17%. The overall rate of missed polyps, pooled from several studies, can range from 6 to 27%.
Although colonoscopy as a tool will never be perfect, safety is critical and should be questioned. It is important to know the TRUE, evidence-based risks for colonoscopy complications before consenting to this as a “screening” procedure.
For example: be sure to ask the physician doing the colonoscopy is, “How many of these procedures do you do per year?” and tell them, “I prefer to not have a resident (a doctor in training) do my test.”
Coming next: Part 3 - What other screenings are available?
Studies reviewed for this substack, in no particular order:
2008: Miss rate for colorectal neoplastic polyps: a prospective multicenter study of back-to-back video colonoscopies.
2009: Risk of perforation from a colonoscopy in adults: a large population-based study.
2009: What are the risk factors of colonoscopic perforation?
2010: Complications of colonoscopy: magnitude and management.
2010: Endoscopist experience as a risk factor for colonoscopic complications.
2012: The Miss Rate for Colorectal Adenoma Determined by Quality-Adjusted, Back-to-Back Colonoscopies.
Many similar articles can be seen in the references of this article.
2013: Adverse events requiring hospitalization within 30 days after outpatient screening and non-screening colonoscopies. (German study).
2014: Polypectomy techniques, endoscopist characteristics, and serious gastrointestinal adverse events.
2019: Adverse events associated with colonoscopy; an examination of online concerns.