What is the primary risk factor for developing an anal fissure?

Chronic constipation is identified as the primary risk factor for developing an anal fissure due to the increased strain it places on the anal region during bowel movements. When an individual is constipated, stools can become hardened and larger, leading to trauma and tearing of the anal mucosa as they pass through the anal canal. This trauma is the initiating factor for fissures, causing pain and potential bleeding during defecation.

Maintaining regular and softer bowel movements through a high-fiber diet, adequate hydration, and weight management can help prevent the occurrence of anal fissures. However, when chronic constipation is present, the risk significantly increases, making it the predominant risk factor in the development of fissures. Other factors may contribute to the likelihood of fissures, but chronic constipation stands out as a primary concern that directly leads to the mechanical injury of the anal canal.