A colonoscopy is a medical procedure that examines the inside of the large intestine, including the colon and rectum. A long, flexible tube with a tiny camera, called a colonoscope, is inserted to visualize the intestinal lining. This procedure detects and prevents conditions like colorectal cancer by identifying and removing precancerous growths called polyps. It is a common diagnostic and screening tool.
Routine Screening Guidelines
For individuals at average risk of colorectal cancer, routine colonoscopy screening is recommended to begin at age 45. This updated guideline, shifted from the previous age of 50, reflects a recent increase in colorectal cancer cases among younger adults. The aim of starting screening at this age is to identify polyps before they develop into cancer.
Following an initial screening colonoscopy with normal results, subsequent screenings are advised every 10 years. This interval allows for regular surveillance of the colon while minimizing the procedure’s frequency. These guidelines are broad recommendations for the general population without specific risk factors, and individual screening schedules can vary based on personal health circumstances.
Warning Signs and Symptoms
Certain symptoms can indicate the need for a colonoscopy, regardless of age. These include:
- Persistent changes in bowel habits, such as new or unexplained diarrhea or constipation.
- Rectal bleeding or blood in the stool, which requires evaluation to rule out serious concerns like colorectal cancer or inflammatory bowel disease.
- Unexplained weight loss, particularly a sudden loss of 3 kilograms (about 6.6 pounds) or more within six months without intentional dieting.
- Persistent abdominal discomfort, including chronic cramping, gas, or pain that does not resolve.
- Unexplained fatigue or weakness, which can be a sign of iron-deficiency anemia from chronic internal bleeding.
- Stools that appear unusually narrow or pencil-thin, suggesting a possible blockage in the colon.
Increased Risk Factors
Beyond age-based guidelines and active symptoms, several non-symptomatic factors can increase an individual’s risk for colorectal conditions, potentially necessitating earlier or more frequent colonoscopies. A personal history of colorectal polyps, especially adenomatous polyps which can become cancerous, increases future risk. The size and characteristics of previously found polyps, such as those 10 mm or larger or those with advanced histology, influence the recommended surveillance interval.
A strong family history of colorectal cancer or certain types of polyps also increases an individual’s risk. If a first-degree relative (parent, sibling, or child) has been diagnosed with colorectal cancer, particularly before age 50, the risk is heightened. Genetic syndromes like Familial Adenomatous Polyposis (FAP) or Lynch syndrome (Hereditary Non-Polyposis Colorectal Cancer, or HNPCC) are associated with an increased lifetime risk of developing colorectal cancer, often requiring earlier and more frequent screenings.
Individuals with a personal history of inflammatory bowel disease (IBD), such as Crohn’s disease or ulcerative colitis, have a higher risk due to chronic inflammation of the colon. The duration and extent of the IBD can influence the recommended frequency of colonoscopies. These factors highlight the need for tailored screening plans that go beyond standard age-based recommendations.
When to Consult Your Doctor
If you have concerns about your bowel health, it is advisable to consult a healthcare professional. Only a doctor can evaluate your complete medical history, assess any symptoms you are experiencing, and consider your individual risk factors. Based on this assessment, they can determine if a colonoscopy or other diagnostic tests are necessary. Discussing any changes in bowel habits, unexplained discomfort, or family history with your doctor is a proactive step toward maintaining your health.