Editing Haemorrhoids (section)

== '''Risk factors''' ==

* Prolonged sitting and     straining
* Chronic constipation
* Other less important factors:
** Age
** Diarrhoea
** Pregnancy
** Pelvic tumours
** Anticoagulation/antiplatelets      (may not be causal)
* There may be an aetiological     relationship between the presence of a portosystemic shunt at the superior     haemorrhoidal veins, and development of actual symptomatic haemorrhoids,     but it is uncertain. Some patients do develop true varices within the     anorectal mucosa.