1. Local anatomical features: There are many special structures in the anorectal area, such as anal flaps, anal recesses, anal papillae, anal glands, etc. When the feces are dry and clumped, the above-mentioned structures may cause damage, which can be caused in the anal recesses and anus. Nipple, anal glands, etc., when the feces are dry and knotted, the above structures may cause damage. Feces accumulate in the anal crypts. Bacteria can cause acute inflammation and infection of the glands at the bottom of the crypts through the injured site. In addition, inflammation stimulates the anal sphincter to contract Exudate retention and poor drainage, the infection is not easy to heal, and it can even spread to the anal canal or outside the rectal wall. Another example is the special vascular structure in this area, the lack of venous valves in the rectal veins, and the blood is easy to pool. Constipation, forced defecation or pregnancy uterus compresses the veins, blood return is blocked, the intravenous pressure increases, the hemorrhoidal vein wall is weak and the varicose veins are enlarged to form mass hemorrhoids.
2. Abnormal defecation: Diarrhea and constipation can cause anorectal disease. The colon and rectum are the main organs that transport food residues and retain feces. After food is digested and absorbed, the residues often contain a lot of harmful substances. Constipation causes long-term retention of toxic substances in the rectum, which can induce cancer. On the other hand, the dryness of feces , Inevitably defecate hard, make the anus bear greater pressure, easy to cause hemorrhoids and anal fissures. Among the 2669 constipation patients surveyed, there were 1989 people suffering from anorectal disease, with a prevalence rate of 74.5%; diarrhea is a common symptom of colitis, and it can also increase the chance of local infection in the anus, causing anal cryptitis, proctitis, etc. . In the statistics of 1523 diarrhea patients, there are 1013 people suffering from anorectal disease, the prevalence rate is 66.5%.
3. Poor defecation habits: Squatting down to defecate for too long, reading, reading newspapers, smoking habits, congestion in the anorectal area and induce diseases. In addition, excessive force during defecation and increased intra-abdominal pressure can lead to the occurrence and development of this disease. For example, habitual constipation can weaken the pelvic floor muscles, reduce tension, and aggravate the congestion of the anorectal area, causing hemorrhoids, rectal mucosal prolapse, and anal sphincter relaxation. Therefore, changing bad bowel habits can prevent the occurrence of anorectal disease.
4. Dietary factors: The variety and quality of the diet in daily life, the type and quantity of vegetables, protein, fat, cellulose, and the amount of water can affect the composition of feces, which can induce or prevent anorectal diseases. People who drink alcohol for a long time or eat spicy foods have a significant increase in the incidence of anorectal disease, which is related to the irritation of the gastrointestinal mucosa by alcohol and spicy foods, causing gastrointestinal disorders. Although it is not necessarily the direct cause of anorectal disease, it has a certain effect on inducing and aggravating anorectal disease.
5. Occupational factors: Long-term sedentary and standing occupations have a high incidence of anorectal disease. Due to standing or sitting still, long-term in a fixed posture will cause hemorrhoid vein congestion, varicose, and swelling, which will increase the incidence of anorectal disease. Young people and soldiers who change their positions have a lower incidence of this disease. According to the census statistics, the prevalence rate of car drivers is the best, accounting for 89%, the prevalence rate of hairdressers, policemen, and salespersons is 81.7%, the prevalence rates of cadres and workers are 71.5% and 70.3%, while the prevalence of soldiers and middle school students The prevalence rate is low, 32.6% and 19.2% respectively. In addition, it was found in the census that the incidence rate of women with multiple pregnancies is much higher than that of non-pregnancy.
6. Other factors: abnormal embryonic development, a variety of congenital anorectal diseases can occur; some genetic defects can cause multiple colonic polyposis.