Chronic constipation: mechanisms, diagnosis, and management

Chronic constipation (CC) affects approximately 15% of the global adult population, making it a prevalent gastrointestinal issue frequently observed in medical clinics. It manifests through various symptoms, such as straining, incomplete evacuation, and anorectal blockage, rather than just reduced stool frequency. Chronic constipation can be classified as either primary or secondary, with colonic sensorimotor disturbances and pelvic floor dysfunction being primary pathogenic mechanisms.
Initial management should emphasize dietary fiber supplementation alongside stimulant or osmotic laxatives. If necessary, treatments may advance to include intestinal secretagogues or prokinetic agents. In cases of opioid-induced constipation, peripherally acting μ-opiate antagonists are recommended. When patients do not respond to these measures, anorectal tests are vital for evaluating defecatory disorders, which often respond well to biofeedback therapy.
For diagnosis, the Rome IV criteria are utilized to distinguish between functional constipation (FC), irritable bowel syndrome with constipation (IBS-C), and defecatory disorders (DDs). The diagnostic process involves a thorough patient history, physical examination, and, if indicated, colonic transit assessments. High-resolution anorectal manometry and balloon expulsion tests are essential tools in identifying DDs. Management varies by individual needs, considering efficacy, cost, and availability. While many patients find relief with dietary adjustments and over-the-counter medications, refractory cases may require advanced treatments such as biofeedback or, in severe cases, surgical interventions like colectomy. Future research should focus on comparing the efficacy of inexpensive laxatives with newer agents and refining management algorithms.