Hemorrhoids

Definition

Hemorrhoids are swollen vascular cushions in the anal canal resulting from increased pressure, venous dilation, or weakening of supporting tissues, causing bleeding, pain, or prolapse.

Epidemiology

• Affects up to 50% of adults at some point in life
• Peak incidence between 45–65 years
• Equally common in males and females
• Pregnancy and chronic constipation increase risk
• Significant cause of outpatient proctology visits

Etiology

• Chronic constipation and straining during defecation
• Pregnancy and increased intra-abdominal pressure
• Obesity and sedentary lifestyle
• Portal hypertension (secondary hemorrhoids)
• Aging-related weakening of connective tissue in anal canal
• Genetic predisposition and family history

Pathophysiology

• Dilation and engorgement of superior and inferior hemorrhoidal veins
• Displacement of anal cushions due to connective tissue weakening
• Inflammation and thrombosis in acute cases
• Prolapse occurs due to stretching and loss of supportive tissue
• Portal hypertension may exacerbate venous congestion