Chronic constipation in older patients
An educational approach
Constipation is one of the most common disorders in Western societies, and its prevalence increases with age. Twenty-six percent of women and 16 percent of men 65 years and older consider themselves constipated. In people over 84, the reported incidence is 34 and 26 percent, respectively.
Many of the factors that predispose older adults to constipation are not a direct consequence of normal aging, though are often closely associated with it. A majority of people over age 65 take one or more medications that affect nerve conduction and smooth muscle function, such as opioids, anticholinergics, NSAIDs, calcium-channel antagonists and calcium supplements. Other factors that increase the risk of constipation in older patients include low-fiber diets, limited fluid intake, impaired mobility and cognitive disorders.
Studies have also shown that distinct physiological changes affecting colonic motility can occur in older people. They include myenteric dysfunction, increased collagen deposits in the left colon, reduced inhibitory nerve input to the colon's muscle layer and increased binding of plasma endorphins to intestinal receptors.
Diminished anal sphincter pressure or degeneration of the internal anal sphincter, loss of rectal wall elasticity, and, in older women, an increased degree of perineal descent also are well documented.
To help determine the cause of constipation and guide treatment, Amy E. Foxx-Orenstein, D.O., of Mayo Clinic in Arizona, says the disorder is typically divided into three primary types:
- The most common is functional constipation. Patients with this type frequently experience small, hard stools that are difficult to pass and straining. They may also have abdominal pain or discomfort that is relieved with stool passage. Intestinal transit times and pelvic function studies are normal.
- The second type is pelvic floor constipation — difficult or inadequate expulsion of stool — due to faulty coordination of the abdominal and pelvic floor muscles, excessive or impaired perineal descent, or anorectal structural abnormalities.
- Dr. Foxx-Orenstein identifies the third type — usually called slow transit constipation — as colonoparesis because its mechanism is similar to that of gastroparesis. "There is some degree of partial paralysis in the colon resulting from dysfunction of the colonic nerves, smooth muscle or both, resulting in delayed evacuation. It may occur as part of a generalized motility disorder affecting the stomach, intestine and/or colon," she explains.
Dr. Foxx-Orenstein stresses that the type of constipation can usually be determined without extensive testing.
"The first step in evaluating an older patient with constipation should always be a detailed history and complete physical exam, including a digital rectal exam," she says. "The digital exam is often overlooked, but it can provide so much information."
She adds that patients with a long delay in evacuation may need colon transit studies. For those with difficult evacuation, anorectal manometry, traditional proctography or MRI defecogram may be needed to help guide treatment.
Treatment: Less is more
Although requiring patience and persistence, treatment should focus on education, Dr. Foxx-Orenstein says. "Informing patients about diet, exercise and bowel techniques, including evacuation timing, breathing and the way they position themselves on the toilet, is usually incredibly effective."
She adds, "That's why we have a dedicated nurse educator who is a great resource for patients. When people understand that this is a natural physiological process, and it's described to them in lay terms that aren't confusing, they can put (the information) to use easily and really benefit."
Dr. Foxx-Orenstein says that she and her group often recommend a daily routine that includes taking a fiber supplement mixed with 2 ounces of water every evening.
"We have very consistent results with powdered fiber in a small amount of water because it improves the consistency and weight of stool," she says, but cautions that some types of constipation — colonoparesis and more severe forms of pelvic floor dysfunction — may not respond to high fiber and may even worsen. "That's why knowing which primary type of constipation is present can be so important."
In this regimen, mornings begin with mild physical activity — sometimes just stretching in bed — a hot, preferably caffeinated beverage and possibly a fiber cereal followed by another cup of a hot beverage — all within 45 minutes of waking. "This routine augments early morning high-amplitude peristaltic contractions by incorporating multiple stimulators," Dr. Foxx-Orenstein says.
Spreading the word
In early March, Mayo Clinic in Arizona began offering a weekly constipation education class jointly conducted by a dietitian and a nurse educator. Patients are referred to the class by a physician and learn general techniques for managing their condition.
"Giving a patient a prescription for laxatives doesn't get at the cause of the problem and provides no long-term solution," Dr. Foxx-Orenstein points out. "But offering information, along with an organized routine, has increased quality of life (in patients) in a way that makes them and us very happy. This is an area that affects everyone, but for older people, especially, constipation can be (psychologically) and physically consuming. We offer them a life plan that works."