Colonoscopy Risks For the Elderly

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    Colonoscopy Risks For Elderly

    The fourth leading cause of cancer and the second leading cause of cancer mortality in the United States is colorectal cancer. Your risk for developing colorectal cancer increases as you age. Consider the following statistics:

    • 42% of new cases of colorectal cancer are in patients over the age of 65
    • Women are at a higher risk at an older age with 27% of all cases diagnosed at the age of 80 or above
    • 40% of deaths due to colorectal cancer occur in women over the age of 80

    Colonoscopies, both screening and diagnostic, are often regularly performed in the very elderly because of this increased risk of developing and dying from colon cancer. 

    Yet, this age group is also at a high risk for developing serious complications before and during a colonoscopy due to the bowel preparation and invasive nature of the procedure itself. Because of this, physicians use a carefully weighed system when deciding if their older patients should undergo colon cancer screening. Doctors understand that the very elderly have a limited amount of years left in their life span and must weigh the risk of them developing cancer with the risk of complications from a colonoscopy.  

    If you are concerned about the risks of a colonoscopy complication for yourself or a loved one who is elderly, this article will help to inform you about complications that are unique to the elderly and address the possible dangers that involve a geriatric colonoscopy. 

    Colonoscopy Risks For The Elderly: A Detailed Statistical Breakdown

    The risks of complications from a colonoscopy definitively increase as you age:

    • In all patients, 3.4% suffer from a complication within 30 days of a colonoscopy
    • In patients over the age of 75, 6.8% will suffer a complications within 30 days
    • In patients between the ages of 80 and 84, there is a 75% higher risk of serious gastrointestinal complications than those of ages 66 to 69 years 
    • There is a 4-fold increased incidence of cardiovascular complications in patients over the age of 75 years as compared to younger individuals 
    • Patients older the age of 60 have an 80% higher risk of pulmonary and cardiovascular complications after a colonoscopy then those aged 50 to 59

    The American Cancer Society recommends that people at an average risk for colorectal cancer begin screening by at least 50 years of age and stop screening after the age of 75. One of the reasons this society recommends people to stop screening for colon cancer after the age of 75 is because of the increased risk for developing a serious complication before, during, and after the procedure. Individuals who are over the age of 75 have twice the risk of developing a complication when compared to people between the ages of 50 and 74. 

    Common complications that occur during or after a colonoscopy include: 

    • 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.
    • 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. However, elderly patients are at a higher risk for an infection because of their weakened immune systems.
    •  Cardiovascular event. Elderly patient will often have a history of cardiovascular disease and/or high blood pressure and are at a higher risk for cardiac 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. 
    • 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. 
    • Perforation. This occurs when a surgical  instrument punctures a thin section of the intestinal wall and causes a tear or hole in the lining. It can also occur if too much air is inserted into the colon during the procedure causing the abdomen to distend and stretch the lining into a tear. If a polyp is removed during a colonoscopy, there is an increased risk for getting a perforation. Elderly patients are at a high risk for a perforation because the colorectal lining thins with age.
    • 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). 
    • 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.

    Colonoscopy Risks That Are Unique For Elderly Patients

    • Bowel preparation complications. Elderly patients are more prone to feeling nauseous, weakness, and vomiting during the intensive bowel cleansing required for a colonoscopy. Fainting is a serious issue in this age group because of the risk of breaking bones from a fall. Other complications of the cleansing is severe dehydration and electrolyte imbalance which can cause a cascade effect of problems, from heart arrhythmias and problems with kidney function. 
    • Delayed perforation. Elderly patients are more prone to having a diverticular disease which causes inflammation in the intestinal lining and an increased risk for perforation, or a tear or hole in the lining. Another factor in the increased risk for a perforation is the aging process itself. Intestinal lining contains the protein collagen which gives the skin and lining of the gastrointestinal tract protection and elasticity. Aging causes a loss in collagen in the human body resulted in a thinning of the lining and loss of elasticity. Thus, perforation occur at a higher rate than the younger patients. 
    • Heavy bleeding. A common complication in the elderly during the procedure is hemorrhage, or heavy bleeding. Older patients typically have more polyps that need to be removed which result in bleeding. The risk for a heavy bleed is 75% higher for patients between the ages of 80 to 84 as compared to individuals under the age of 70. 
    • Adverse medications reaction. Elderly patients are more susceptible to having an adverse reaction to all types of medications, including the cleansing agents used during bowel preparation and the sedation or anesthesia medications. 
    • Bacterial infection. The risk of a bacterial infection is typically low in the United States as hospitals and doctor’s offices follow strict sterilization standards. Elderly people are at a higher risk from developing sepsis, a life-threatening infection, after a colonoscopy due to their weakened immune system and inability to fight off a microscopic exposure to bacteria. 

    Are Colonoscopies Dangerous For Elderly Patients?

    The primary reason that the risk for a complication increases with age is the comorbidities that an individual brings into the doctor’s office. More specifically, patients over the age of 80 are at a much higher risk for a complication if they have a medical history of diabetes or cardiovascular disease. Other comorbidities common in elderly patient that increase the risk for a colonoscopy complication include:

    • Anemia
    • Cardiac arrhythmia
    • Congestive heart failure
    • Chronic kidney disease
    • Liver disease
    • Obesity
    • History of smoking tobacco
    • Type 2 diabetes
    • Cardiovascular disease

    The US Preventive Services Task Force guidelines recommend against patients older than 85 years of age getting screened for colorectal cancer. There are several reasons why the Task Force has determined that elderly patients do not benefit from a colonoscopy screening when compared to younger individuals. Primarily, however, it is because physicians conclude that the risk of screening-related complications is substantially higher than the benefit from screening when considering the following: 

    • Diminished life expectancy
    • Competing causes of death (for instance, screening diminishes risk for colon cancer while dying from other causes increases)
    • Risk of dehydration and electrolyte disturbance during bowel cleanse
    • Risk of stopping medications (such as blood thinning medications or insulin)
    • Impact of kidney function from bowel preparation and procedure
    • Increased risk of bowel perforation, hemorrhage, and stroke during and after the procedure
    • Increased risk of cardiovascular and respiratory events after procedure

    For physicians, the decision to screen for colon cancer may be determined dependent on their patient as an individual. A healthy 85-year-old with no comorbidities may benefit from a colon cancer screening due to the patient’s increased risk of developing precancerous polyps (adenomas) in this age group. Colorectal cancer is highly treatable in its earliest stages by detection and removal of polyps found during a colonoscopy. Older patients have a better chance of surviving the treatment if a cancer is caught early than enduring the intense treatment regime that involves more advanced stages of cancer. 

    Yet, for another 85 year old with significant comorbidities (such as advanced dementia, cardiovascular diseases, and chronic kidney disease) which can shorten the expected lifespan of an individual over the age of 75, the risk of a colonoscopy complications may begin to outweigh the risk of colon cancer. 

    If you are older than the age of 75 and are concerned about your risk for colon cancer, be open with your physician and discuss your options. There are several non invasive colon screenings that do not put you at risk for a complication that may be used as an alternative to a colonoscopy. 


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