Causes and Risk Factors of Hemorrhoids

The causes of hemorrhoids involve a variety of complex physiological and environmental factors. From an anatomical perspective, the core mechanism for the formation of hemorrhoids is the prolonged pressure or obstruction of blood flow in the venous plexus around the anus. When the elastic tissue of the venous wall is damaged or the valve function is abnormal, blood retention leads to vascular dilation, ultimately forming palpable swollen tissue. This process may be accelerated by congenital conditions, lifestyle habits, or external stimuli.

Modern medical research indicates that the pathogenesis of hemorrhoids is related to multiple factors, including venous hypertension, atrophy of connective tissue, and abnormal neural regulation. Aging, physiological changes during pregnancy, and increased chronic abdominal pressure are key factors that contribute to damage to the venous system. Environmental and behavioral factors can exacerbate these pathological changes, leading to clinical symptoms. A deeper understanding of these causes can help in developing prevention strategies and personal health management.

Genetic and Family Factors

Genetic predisposition plays a fundamental role in the onset of hemorrhoids. Patients with a positive family history may have a more fragile congenital structure of the anal venous system. Studies show that individuals with a family history of hemorrhoids have a 30-40% increased risk of developing the condition. This genetic predisposition may be related to the following genetic characteristics:

• Congenital deficiency of elastic proteins in the venous wall (such as elastin)
• Differences in the repair capacity of connective tissue around the anus
• Individual differences in neurovascular responses

Certain populations, such as those with familial connective tissue disorders, tend to develop hemorrhoids at an earlier age and have higher recurrence rates. The interaction between genetic factors and acquired behaviors further exacerbates the degree of pathology.

Environmental Factors

Environmental exposure primarily impacts hemorrhoids through behaviors that increase intra-abdominal pressure over the long term. The following environmental conditions can directly exacerbate pressure on the venous system:

• Heavy physical labor: Activities that require prolonged weight-bearing or lifting heavy objects can lead to increased pelvic pressure
• Constipation environment: Areas with insufficient dietary fiber have a positive correlation between chronic constipation rates and hemorrhoid incidence
• Prolonged sitting environment: Office workers who sit for extended periods increase anal venous pressure, with a 25% higher risk of developing hemorrhoids compared to the general population

Climatic factors may also indirectly influence this, as dry climates can lead to insufficient fluid intake, resulting in hardened stools. Chronic cough due to environmental pollution can also increase abdominal pressure due to prolonged straining during breathing, forming an indirect pathogenic factor.

Lifestyle and Behavioral Factors

Modern lifestyle patterns are closely associated with the onset of hemorrhoids. The following behavioral patterns can directly damage the venous circulation system:

In terms of dietary habits, a low-fiber diet (with daily fiber intake below 15 grams) can lead to a reduced frequency of bowel movements, increasing abdominal pressure during defecation. Artificial additives in processed foods may disrupt the balance of intestinal probiotics, further exacerbating constipation. Additionally, excessive alcohol consumption can lead to chronic dehydration, making stools harder.

• Prolonged sitting posture: Sitting for more than 4 hours daily (such as driving or office work)
• Poor toilet habits: Reading or extending the time spent on the toilet
• Lack of exercise: Insufficient physical activity leads to decreased intestinal motility

These behaviors can cause the rectal venous plexus to remain in a congested state for an extended period, gradually impairing the regulatory function of venous valves, ultimately forming palpable swollen tissue. The cumulative effect of behavioral factors and environmental factors can exponentially increase the risk of developing hemorrhoids.

Other Risk Factors

The following special conditions can directly damage the vascular structure around the anus:

Pregnant women experience a high incidence of hemorrhoids, up to 50%, due to uterine pressure on the pelvic veins. The straining during childbirth can further cause permanent damage to the venous walls. Obese individuals, with abdominal fat accumulation increasing abdominal pressure, have a threefold higher risk of developing hemorrhoids if their body mass index (BMI) exceeds 30.

• Chronic cough or asthma: Repeated increases in abdominal pressure due to prolonged straining during breathing
• Metabolic diseases: Microvascular complications in diabetic patients may damage the anal venous plexus
• Drug effects: Long-term use of laxatives can lead to dysregulation of intestinal nerve control

Regarding surgical history, individuals who have undergone pelvic surgery may experience changes in venous flow pathways due to fibrosis in surrounding tissues. These risk factors may act alone or in combination, leading to irreversible changes in venous dilation.

In summary, hemorrhoids are the result of multifactorial interactions. Genetic inheritance provides a basic susceptibility, while acquired behaviors and environmental factors exacerbate pathological changes, and medical or physiological special conditions may serve as critical triggers. Prevention strategies need to systematically intervene in these key factors, such as improving toilet habits, increasing dietary fiber intake, and regularly performing pelvic floor exercises to strengthen pelvic muscle function.

 

Frequently Asked Questions

How can I determine if blood in my stool is related to hemorrhoids rather than other intestinal issues?

Bleeding caused by hemorrhoids is usually bright red and minimal, possibly accompanied by blood on toilet paper or drops of blood after bowel movements. If the blood is dark red, mixed with mucus, or persists for more than two weeks, it may involve other issues such as intestinal fistulas or polyps, and immediate medical examination is necessary to rule out serious conditions.

How can office workers who sit for long periods prevent hemorrhoids from worsening?

Avoid maintaining the same posture for extended periods; stand up and move for 5 minutes every 30 to 45 minutes, and use foot pads or cushions to relieve pressure. Regularly strengthening pelvic floor exercises, such as Kegel exercises, can help improve local circulation and reduce the risk of blood pooling.

Is it possible for hemorrhoids to recur after surgery? What long-term care recommendations are there?

About 10-20% of patients may experience recurrence after surgery, with the key being to maintain good bowel habits. It is recommended to use the toilet at a fixed time each day, avoid excessive straining, increase dietary fiber intake, and maintain regular exercise to effectively reduce the likelihood of recurrence.

What safe relief methods are available for worsening hemorrhoid symptoms during pregnancy?

Avoid using medication during pregnancy; you can relieve symptoms by elevating the legs during bowel movements, using cold packs to reduce swollen veins, or consuming high-fiber vegetables and sufficient water to keep stools soft. If pain is severe, consult a physician for a local anesthetic ointment that is safe for the fetus.

What are the mechanisms and contraindications of non-surgical hemorrhoid suppositories or ointments?

Suppositories typically contain astringent ingredients (such as witch hazel) or steroids, which can reduce swelling and stop bleeding, but should not be used for more than a week, as this may lead to atrophy of the skin around the anus. Severe thrombosed hemorrhoids or infections should not be self-treated; a physician should evaluate the treatment options.