Colonoscopy Risks For Young Adults

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    A colonoscopy is typically a procedure that is performed on people who are over the age of 50 to screen for colorectal cancer. However, if you are a young adult (which in the world of colonoscopies is under the age of 50) there are many reasons that your physician may ask you to get a colonoscopy. These include to diagnose gastrointestinal disorders and inherited genetic disorders of the colon and to catch colon cancer before it spreads. Young adults are typically asked to get a colonoscopy for the following reasons:

    • Family or personal history of colorectal cancer
    • Family or personal history of familial adenomatous polyposis or Lynch syndrome
    • Personal history of inflammatory bowel disease
    • Gastrointestinal symptoms 

    In this article you will learn about the alarming rate at which colorectal cancer is raising among younger adults, the reasons young adults are asked to get a colonoscopy, and associated risk of complications that patients may experience because of a colonoscopy.

    Young adults who need a colonoscopy have a history of colorectal cancer, ulcerative colitis, or gastrointestinal symptoms.

    Risk Factors for Colorectal Cancer in Young Adults

    Colorectal cancer rates are rising at an alarming rate in younger populations. Since 1998, the overall incidence of colorectal cancer has been decreasing, except in young adults. In those between the ages of 20 to 39 years, the incidence rates of colon cancer are slowly creeping up every year. Since the 1980s, colorectal cancer has increased from between 1-2.4% every year among young adults. Colonoscopies are generally considered a safe procedure with a low rate of complications. Nonetheless, there is a risk for complications in young adults, especially if they have a preexisting gastrointestinal-related disease or disorder.

    Since 1998, the overall incidence of colorectal cancer has been decreasing, except in young adults. In those between the ages of 20 to 39 years, the incidence rates of colon cancer are slowly creeping up every year.

    Young-onset colorectal cancer refers to adults under the age of 50 who are diagnosed with colon cancer. Millenials are 2-4 times more at risk for developing colon cancer at a younger age as compared to their grandparents. Young adults are diagnosed at a later stage where the cancer has spread outside of the colon and needs to be treated aggressively with radiation and chemotherapy.

    The cause of these rising numbers of colon cancer cases in young adults is a mystery to experts. There are risk factors that may contribute to the spike in young adults. These include:

    • Genetic conditions such as Lynch Syndrome and familial adenomatous polyposis
    • Inflammatory bowel disease, such as ulcerative colitis and Crohn’s disease
    • Obesity
    • Low activity level
    • Unhealthy diets 
    • Gut inflammation

    RIsks and Complications of a Colonoscopy in Young Adults

    The risks for complications associated with a colonoscopy can be different for young adults, especially if you have a preexisting health condition such as Crohn’s disease or Lynch syndrome.

    Like complications for older adults, the risk for getting any complication is rare but still does occur. Further, the risks for complications associated with a colonoscopy can be different for young adults, especially if you have a preexisting health condition such as Crohn’s disease or Lynch syndrome. Complications and longer-lasting side effects after a colonoscopy occur more frequently in the following groups of young adults:

    • Women
    • Patients with history of stroke, diabetes, and/or heart disease
    • Patients with a history of COPD (chronic obstructive pulmonary disease)
    • Patients who are on blood thinners
    • Patients who undergo a polypectomy (removal of a polyp)
    • Patients with inflammatory bowel disease (IBD)
    • Patients with a history of colon cancer

    The risks for complications associated with a colonoscopy can be different for young adults, especially if you have a preexisting health condition such as Crohn’s disease or Lynch syndrome. Like complications for older adults, the risk for getting any complication is rare but still does occur. Younger adults also suffer from the same complications as any person undergoing a colonoscopy. These include:

    Dehydration and electrolyte imbalance. The bowel cleanse preparation before a colonoscopy involves the use of laxatives that cause the body to lose large amounts of water which can cause dehydration. A patient may also suffer from an electrolyte imbalance which can cause the heart to beat irregularly due to potassium imbalance. Young adult patients who are at a high risk for developing complications from the bowel preparation include:

    • Pregnant women
    • People with kidney, liver, or heart problems
    • People with inflammatory bowel disease (IBD)

    Perforation. If you have a polyp removed during a colonoscopy, you are at a higher risk for getting a perforation, or a tear or hole in the lining of the intestine. You are at a much lower risk for a perforation if you did not have a polyp removed and a much higher risk if you have several polyps removed. There are cases where an instrument may puncture a thin section of the intestinal wall and cause a tear or hole. If your examiner introduces too much air in the colon during the procedure, the distention of the abdomen can also cause a perforation. 

    GI bleed. Bleeding occurs during a colonoscopy in approximately 1 in every 1,000 patients. The bleed is typically treated immediately as it occurs during the procedure. Often the bleeding goes away naturally without any treatment intervention. If the bleeding is severe, you will need immediate treatment. 

    Cardiovascular event. Patients who have a history of cardiovascular disease or high blood pressure are at a higher risk for this complication during a colonoscopy. The loss of potassium from the bowel cleanse can cause heart-related issues such as atrial fibrillation or tachycardia (rapid heart rate). The sedation used during the procedure can also put extra pressure on the heart, especially in older patients and cause a heart attack, stroke, or slowed heart rate. 

    Respiratory distress. Sedation that involves anesthesia can cause low oxygen levels,slowed breathing, and respiratory distress. For this reason, many nurses and anesthesiologists will give oxygen to patients during a colonoscopy.

     Postpolypectomy electrocoagulation syndrome (PES). This complication occurs when a patient suffers an electrical burn to the intestinal lining caused by a removal of a polyp or polyps. It is known as an electrocoagulation burn and causes the lining of the intestines to become inflamed and causes a lesion. Symptoms of PES include abdominal pain, fever, and a rapid heart rate (tachycardia). 

    Allergic reaction. Allergic reactions to sedation are very rare, but do occur in patients during a colonoscopy. If an allergic reaction occurs during the colonoscopy the patient is treated immediately. Be sure to tell your medical team about any allergies you have, including food (for example egg and soybean), so they are prepared to give you the proper medication. 

    Bacterial infection. If the colonoscopy tools are not completely clean or disinfected they may harbor bacteria like E. coli that can be transmitted during a routine colonoscopy. Bacterial infections from these instruments are very rare due to strict sterilization practices of healthcare centers. 

    Overall Rate of Colonoscopy Complications

    The overall risk of complications for a routine colonoscopy is 1.6%. Compared to the risk of developing colorectal cancer being between 4-5%, the benefits of getting a colonoscopy outweigh the risk of having a complication. Young adults usually are at a much lower risk for a complication than older patients, especially those over the age of 70. If you are a young adult and are awaiting a colonoscopy because you are suffering from gastrointestinal bleeding or discomfort, you may be concerned that you are at risk for a complication. In this article, you will learn about the different complications associated with a colonoscopy that may occur and if they are a safe procedure. Any questions or concerns you have can be brought to the attention of your physician. Make it a point to discuss any and all worries you have, as your physician can help you to understand the risks and benefits of a colonoscopy. 

    Specific Complications Statistical Rates 

    Cardiopulmonary Complications – Cardiopulmonary complications occur in almost 1% of all procedures and make up for 67% of unplanned events during an endoscopic procedure. Keep in mind that these complications usually occur in older adults with risk of an event increasing with age. This type of complications include hypotension, hypoxemia, angina, heart attacks, and strokes.

    Hypotension or low blood pressure – 480 per 100,000 colonoscopies

    Hypoxemia or low oxygenation – 230 per 100,000 colonoscopies

    Post-colonoscopy heart-related events, including angina, heart attack, and stroke – 1030 per 100,000 procedures

    Hemorrhage (Risk for bleeding increases with polyps size) – .1%-.6% or 1-6 per 1000 procedures

    Transient bacteremia or bacterial infection – 4 % of all procedures (ranges from 0%-25%)

    Perforations  – .1%-.3% of all procedures or 1-3 per 1000 procedures

    Postpolypectomy electrocoagulation syndrome – .003%-1% or 3 per 100,000 to 1 per 1000 procedures

    Bloating – 25 % of all procedures

    Abdominal pain – 5%-11% 

    Risks That Are Unique To Young Adults

    Acute appendicitis is considered a very rare event after a colonoscopy. The procedure is generally very safe with a low risk for a complication, especially when performed by a skilled gastroenterologist. However, in some cases, patients will develop appendicitis within a few days of a colonoscopy for reasons unknown. Possible causes of appendicitis are:

    • Barotrauma caused by the inflation of the bowels during the procedure
    • Compression of stool in the appendix leading to inflammation or obstruction
    • Direct trauma caused by the accidental insertion of the endoscope into the appendix
    • Pre-existing condition leads to exacerbation of appendicitis symptoms

    In some cases, appendicitis can be diagnosed during a colonoscopy because a patient may not be showing any symptoms of inflammation or infection of the tiny organ. Appendicitis caused by the colonoscopy procedure itself is known as post colonoscopy appendicitis. Young adults who have a higher risk for developing postcolonoscopy appendicitis are men and patients with a history of ulcerative colitis. People with ulcerative colitis may cause inflammation in the appendix which compromises blood supply and may predispose a patient to postcolonoscopy appendicitis. 

    Are Colonoscopies Dangerous For Young Adults?

    Between 15-20 million people undergo a colonoscopy yearly in the United States and approximately 2% of people who get a colonoscopy experience a complication from the procedure. Young adults are generally more robust than older people and suffer less complications associated with the cardiovascular system, such as heart attack, stroke, or irregular heart beat.

    However, many people who are young that need a colonoscopy have an underlying health condition that increases the risk of a complication due to gastrointestinal inflammation. For example, younger adults who have ulcerative colitis will need a colonoscopy to screen for colorectal cancer due to increased risk. Unfortunately, the nature of the disease, inflammation of the bowels, is worsened by bowel preparation which increases a person’s risk for perforation and bleeding complications during and after the procedure. 

    People who have an inherited polyposis syndrome, like Lynch syndrome, also need to get colonoscopies at a younger age. But, the removal of several polyps increases a person’s risk for bleeding and infection, so these patients are at a much higher risk for a complication. It would seem that colonoscopies are dangerous for young adults who have Lynch syndrome or an inflammatory bowel disease. Nonetheless, their risk for developing colorectal cancer is high enough to warrant accepting the risk of a colonoscopy complication over getting cancer. If you are concerned about your risk for a complication as a young adult, talk to your physician and express your concerns. Most gastroenterologists are highly knowledgeable about complications associated with a colonoscopy and they will be able to walk you through the procedure and help you understand the risk versus benefit of a colonoscopy. 


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