IBS in the Elderly
It is estimated that there will be 71 million elderly people by the year 2030. This is a substantial increase from the year 2000, when there were 34 million elderly people. Along with this increased population comes a higher prevalence of chronic diseases, especially gastrointestinal diseases that present with abdominal pain, constipation, diarrhea, or fecal incontinence.
In younger people, IBS is diagnosed on clinical signs and symptoms, since there is no definitive diagnostic test for IBS. Older people share the same symptoms of IBS as younger people, however, when the elderly present to a physician with abdominal complaints and changes in bowel habit, the physician must be suspicious of other more serious disorders, for example, colorectal cancer. Other disorders that must be ruled out through laboratory tests or imaging studies are diverticulitis, colonic ischemia, Crohn’s disease, and medication side effects.
Colorectal cancer, or cancer that occurs in the colon or the rectum, usually occurs in people greater than 50 years old. The symptoms usually depend on where the cancer is located in the colon. Right-sided cancers present with anemia, blood in the stool not visible with the eye, and weight loss. Left-sided cancers present with bleeding from the rectum, abdominal or back pain, constipation, and intermittent diarrhea. Complications of colorectal cancer include metastasis (spread to other organs) and surgical resection.
Diverticulitis is a condition where the diverticula, or out-pouchings of the colon, become infected. It is primarily seen in the elderly population and presents with left lower abdominal pain, fever, and an altered bowel habit. Serious complications of diverticulitis include obstruction, which may need surgery to be cured.
Colonic ischemia, or ischemic colitis, happens when the arteries to the colon are disrupted, decreasing oxygen to the area. Patients will present with abdominal pain, fever, vomiting, diarrhea, and bloody stools. Ischemia of the colon is a medical emergency that requires immediate care and surgery if it does not resolve.
Crohn’s Disease is an inflammatory disease that can occur anywhere along the gastrointestinal tract, although the small intestine and the colon are the most common sites. The inflammation involves all layers of the intestinal wall. It occurs in younger persons 15-35 years old and older persons 70-80 years old. People with Crohn’s disease complain of abdominal pain, fever, diarrhea, fatigue (tiredness), and weight loss. A sigmoidoscopy, colonoscopy, or barium enema may reveal abnormalities such as ulcers, cobblestoning, and skip lesions.
The elderly are more likely to be on several medications when compared to younger people. Medications that can cause symptoms similar to diarrhea-predominant IBS include laxatives, antacids, thyroid hormones, selective serotonin reuptake inhibitors (SSRIs) and metformin. Medications that can cause symptoms similar to constipation-predominant IBS include narcotics, calcium-channel blockers, and anticholinergics.
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