Constipation: Symptoms and Risk Factors

Constipation refers to the difficult or infrequent passage of stool. A common definition of constipation is fewer than three spontaneous, complete bowel movements per week.

It is the most common gastrointestinal complaint in the United States, occurring in about 15 to 20 percent of adults. It is also a common pediatric condition. Many cases are related to behavioral issues. However, children also suffer from dietary causes, which include fiber deficiencies, dehydration, and dairy intolerance. Constipation occurs in cystic fibrosis and lead poisoning as well.

Certain medications have constipation as a side effect. These include antihistamines, narcotics, antacids, calcium channel blockers, tricyclic antidepressants, and many other drugs. Drugs are a particularly common cause in the elderly.

Other potential causes include smoking cessation (due to nicotine withdrawal), Parkinson's disease, hemorrhoids, and hormonal disturbances (e.g., hypothyroidism).

Symptoms

• Hard, dry stool, which is difficult to pass or leaves the sensation of incomplete passage
• Infrequent bowel movements
• Bloating and abdominal discomfort. These symptoms are more common in irritable bowel syndrome (IBS) than constipation from other causes. IBS can be differentiated from simple constipation by the presence of other digestive symptoms.
• In severe, long-standing cases, low-back pain, rectal bleeding, or hemorrhoids may occur.

Risk Factors

The highest reported prevalence occurs in persons over age 60, followed by children under age 10. The association with age is largely attributable to other factors, such as medication and diet.

For reasons that are unclear, Caucasians report constipation less frequently than do other racial groups, and women are affected approximately twice as often as men. The condition is more common in poorer individuals. Additional possible risk factors include family history, pelvic floor dysfunction, pelvic and abdominal surgery, and childbirth.