Causes of piles (haemorrhoids)

By Dr. Ananya Mandal, MDReviewed by April Cashin-Garbutt, MA (Editor)

Piles or haemorrhoids are basically lumps within the rectum or around the anus that contain swollen and engorged blood vessels. This condition may usually exist without symptoms but in some cases there may be bleeding with passage of stool and bleeding.

Types of piles

Piles may be of two classic types:

• Internal haemorrhoids present just inside the anus, at the beginning of the rectum. There is a line of demarcation between the rectum and anal canal called the dentate line. Internal haemorrhoids lie above the dentate line. These are usually painless and sometimes tend to bleed.
• External haemorrhoids that is present at the anal opening often hanging outside the anus. These lie below the dentate line. These may be painful.

Pressure on blood vessels

The cause of haemorrhoids or piles is usually excess pressure on blood vessels in and around the anus. This may occur in individuals with long term constipation. When they strain to pass the stools there is increased pressure on the blood vessels within the rectum and anal canal that leads to their swelling and inflammation. 1-7

Risk factors of piles

Risk factors of haemorrhoids or piles include:

• Long term constipation due to lack of fiber in diet. Excessive straining leads to piles.
• Diarrhea over long periods of time may also lead to piles.
• Being obese or overweight raises risk of piles.
• Regular lifting heavy objects and those who perform strenuous manual labor are at risk of piles.
• Those whose occupation require sitting for long durations are at risk of pressure on the anal blood vessels that may lead to piles.
• Pregnancy is one of the most common risk factors of piles. With the growing baby within the pelvis the blood vessels in the pelvis get pressed and this leads to enlargement of the anal and rectal blood vessels and development of piles. These piles usually disappear after child birth.
• Risk of piles rises with age. Those over 50 are at a greater risk of piles. This is because the supporting tissues of the rectum and anal canal get weaker with age and thus give way to allow piles to develop.
• Some individuals have a familial risk of developing piles. They may inherit weaker blood vessels that have a greater risk of swelling and leading to piles.
• Infections around the anal canal also render the blood vessels weak and straining and constipation may raise the risk of piles.
• Liver cirrhosis leads to swollen and engorged veins within the rectum called varicose veins. These may occur without constipation and may lead to bleeding and other complications. Ascitis or collection of excess fluids within the abdomen also leads to risk of piles. Ascitis is caused by liver diseases like cirrhosis. The swollen abdomen also presses on the blood vessels leading to piles.
• Chronic cough persistently raises the pressure within the abdomen and may lead to piles
• Persons practicing anal intercourse over a prolonged period of time are at risk of piles. This is caused by weakening of the anal and rectal muscles.
• Persons who have had surgery of the rectum or anus before are at a similar risk of piles since the muscles of their rectum and anus may be weak and straining may lead to piles.

Further Reading

• All Piles (Haemorrhoids) Content
• Piles - What are piles?
• Symptoms of piles (Haemorrhoids)
• Diagnosis and treatment of piles (Haemorrhoids)
• Prevention of piles (Haemorrhoids)