Constipation is not only a disease but also one of the most common digestive symptom clinically. It manifests as difficulty passing stool and hard, dry stool. The incidence of chronic constipation is approximately 1%, with a male-to-female ratio of approximately 1:3. The incidence rate increases with age.
Epidemiology
EpidemiologyIn Western countries, the prevalence of constipation ranges from 1.9% to 28%, but most reports place it between 10% and 20%. Literature reports place the prevalence in Hong Kong at 14%. Previous epidemiological surveys have shown that the prevalence of constipation in my country is mostly between 3% and 5%, lower than most reports abroad. In recent years, the prevalence of constipation in my country has gradually increased. A survey of urban populations in my country revealed that approximately 6% of the population suffers from constipation. Constipation can occur in people of all ages, and the prevalence increases with age, reaching as high as 67.8% in the elderly. Constipation is more common in women than in men. The prevalence of constipation is also influenced by socioeconomic conditions, psychological stress, geography, and lifestyle. Low-income and less educated people have a higher prevalence of constipation. Black people are more susceptible to constipation than Caucasians. People who engage in inactive physical activity also have a higher prevalence of constipation.
High-risk populationElderly, female
symptom
Typical manifestations
Patients with chronic constipation have fewer than three bowel movements per week, and defecation is difficult, with a feeling of blockage in the rectum and anus, a feeling of incomplete defecation, and prolonged defecation. Most patients take more than 15 minutes to defecate. The feces discharged are dry and hard, with shapes like sheep feces or pellets. The mechanical stimulation of hard feces causes the rectal mucosa to secrete mucus, which often covers the surface and gaps of hard feces. Patients sometimes experience bloating and pain in the left lower abdomen. Constipation patients are often accompanied by hemorrhoids, and some patients may also experience symptoms of gastric dysfunction such as fullness in the upper and middle abdomen, nausea and belching. Most patients do not have obvious physical signs. Some patients can palpate spasmodic and contracted intestines or intestines filled with fecal balls in the left lower abdomen.
1. Classification based on the severity of constipation and related symptoms and the degree of impact on life
(1) Mild: refers to mild symptoms that do not affect life and can be cured through overall adjustment or short-term medication.
(2) Moderate: between mild and severe.
(3) Severe: refers to symptoms that are severe and persistent, seriously affecting work and life, requiring drug treatment, which cannot be stopped or is ineffective.
2. Complications
(1) Digestive system: There is a certain relationship between chronic constipation and colorectal cancer. It has been reported that a bowel movement frequency of less than 3 times a week is one of the risk factors for colorectal cancer. Male patients with constipation are more likely to develop distal colon cancer, while female patients are more likely to develop proximal colon cancer. Patients with chronic constipation are prone to colon diverticula. Colon diverticula caused by constipation are more common in the elderly and are more common in the sigmoid colon and left colon. Generally, there are no special clinical manifestations. Long-term use of laxatives such as senna leaves and rhubarb by patients with chronic constipation can lead to colon melanosis. This disease generally has no obvious symptoms. Under colonoscopy, the lesions are black, brown or dark gray. Histological examination reveals a large amount of melanin deposition and infiltration of large mononuclear cells containing melanin in the lamina propria. Colon melanosis may be related to the incidence of colon cancer.
(2) Urogenital system: Chronic constipation often causes many urinary symptoms, including bladder stones and upper urinary tract dilatation. Prostatic discharge is also associated with constipation. The bladder of constipated patients responds quickly and strongly to carbachol.
(3) Breast disease: Chronic constipation can increase the risk of breast cancer in female patients, but the use of laxatives or self-reported constipation has no predictive value for the occurrence of breast cancer.
(4) Others: Severe constipation makes defecation difficult, which increases the burden on the heart and insufficient blood supply to the brain. Therefore, patients with heart and brain diseases should maintain smooth bowel movements. Chronic constipation can cause many discomforts, which often leads to excessive use of medication and unnecessary surgery.
reason
OverviewChronic constipation can be caused by many factors, which can be divided into primary constipation and secondary constipation. Primary chronic constipation is related to lifestyle, psychological factors, and anatomical abnormalities, while secondary chronic constipation is often caused by various diseases and some medications.
Cause of symptoms
1. Primary constipation
(1) Lifestyle habits: People who eat less, eat a low-calorie diet, eat a low-fiber diet, eat irregularly, skip breakfast, do other things while eating, or have low fluid intake are prone to constipation. Some patients have bad bowel habits, ignore or suppress normal bowel movements, use inappropriate bowel movements and postures, and frequently take laxatives or enemas, which can weaken the sensitivity of the rectal reflex and suppress the defecation reflex, leading to constipation.
(2) Psychological factors: People with high work pressure, mental stress, and psychological pressure are prone to constipation. Many constipation patients have mental disorders such as depression and anxiety. Patients with fecal incontinence and constipation may exhibit certain behavioral abnormalities, which will disappear as constipation symptoms improve. Mental stress and inhibition may cause constipation by inhibiting the control of the peripheral autonomic nervous system to the large intestine.
(3) Gastrointestinal hormones and neurotransmitters: Gastrointestinal hormones are divided into excitatory and inhibitory types. Excitatory gastrointestinal hormones include motilin, gastrin, cholecystokinin, substance P, 5-hydroxytryptamine, etc., while inhibitory gastrointestinal hormones are composed of vasoactive intestinal peptide, somatostatin, nitric oxide, neurotensin, neuropeptide Y, and peptide tyrosine. The results of many studies have found that the decrease of excitatory gastrointestinal hormones leads to a decrease in gastrointestinal motility, thereby causing constipation. Studies by Perston et al. suggest that the secretion of motilin and gastrin is impaired in patients with constipation. Many studies have found that the content of substance P in the plasma and intestinal mucosa of patients with constipation is significantly lower than that of healthy people. The expression of 5-hydroxytryptamine 3 and 5-hydroxytryptamine 4 receptor subtypes in the colon of patients with constipation is downregulated. Nitric oxide, as an inhibitory neurotransmitter in the gastrointestinal tract, can relax intestinal smooth muscle. In patients with chronic constipation, the amount of nitric oxide-producing fibers in the intestinal wall increases and is densely distributed. It is speculated that excessive release of nitric oxide enhances the inhibitory effect on intestinal motility, causing constipation.
(4) Anorectal anatomical abnormalities: Some patients with constipation have local anatomical abnormalities such as sigmoid colon intussusception, rectal mucosal prolapse, and rectocele. These abnormalities can cause functional obstruction of the defecation outlet and lead to constipation.
2. Secondary constipation
(1) Endocrine and metabolic abnormalities: Endocrine and metabolic diseases that cause chronic constipation include diabetes, hypothyroidism, hypopituitarism, hypokalemia, hypercalcemia, porphyria, amyloidosis, pheochromocytoma, glucagonoma, etc.
Diabetic patients may experience constipation due to myenteric plexopathy, which may reduce postprandial sigmoid colon contraction activity. In patients with hypothyroidism and constipation, gastrointestinal transit time is significantly prolonged.
(2) Neuropathy
① Central nervous system diseases: cerebrovascular accident, brain tumor, spinal nerve or spinal cord injury, spinal cord tumor, Parkinson’s disease, multiple sclerosis, cauda equina tumor, etc.
② Peripheral neuropathy: congenital megacolon, intestinal wall ganglion cell and ganglioneuroma disease, autonomic neuropathy, etc.
③ Other: Lumbar spinal cord trauma significantly reduces the colon’s compliance and tolerance to fluid distension, leading to a lack of response to food, which can cause constipation. Multiple sclerosis patients experience decreased colonic contractility and prolonged colonic transit time, making them more susceptible to constipation. A decrease or increase in the number of ganglia in the myenteric plexus can also contribute to constipation.
(3) Systemic diseases: Systemic diseases including systemic scleroderma, dermatomyositis, chronic obstructive pulmonary emphysema, uremia, lead poisoning, etc. can cause constipation. These systemic diseases affect the smooth muscle motility of the intestine, weakening intestinal motility and prolonging the colorectal transit time, thus causing constipation symptoms.
(4) Medication: Many medications have the side effect of constipation. However, once the medication is stopped, constipation will also be relieved. Common medications that cause constipation include antidepressants such as imipramine and doxepin, analgesics, morphine sustained-release tablets, certain antibiotics, belladonna anticholinergics, aluminum or calcium-containing antacids such as sucralfate, and bismuth-containing preparations such as Dextromethorphan. In addition, the abuse of antidiarrheal or laxative drugs may also cause constipation.
3. Pathogenesis
(1) Abnormal gastrointestinal motility
① Prolonged colorectal transit time leads to longer intervals between bowel movements and fewer bowel movements in constipated patients. Constipated patients experience prolonged colon and rectal transit time, with some patients experiencing predominantly prolonged transit time throughout the entire colon, while others experience predominantly prolonged transit time in the right colon, left colon, or sigmoid colon.
② The defecation pressure in the rectum and anal canal increases, and the resistance of feces passing through the anal canal increases, making defecation difficult for patients with constipation.
③ The cycle of the small intestinal interdigestive migrating motor complex (MMC) is prolonged and the conduction velocity is reduced, causing the defecation interval of patients with constipation to be prolonged and the number of defecation to be reduced.
④ Some patients with constipation not only have abnormal colorectal motility, but also have abnormal motility of upper gastrointestinal organs such as the esophagus and stomach.
(2) Incoordination of rectal and anal canal movements
Defecation is a complex and coordinated movement process. When feces reaches the rectum, the rectum contracts, which reflexively causes the internal and external sphincters to relax. This series of coordinated movements completes the defecation process. Incoordination of the above muscle movements may cause defecation disorders.
(3) Rectal paresthesia
Many studies at home and abroad have found that patients with constipation have rectal numbness.
(4) Abnormal secretory function
Animal studies have shown that constipated animal models have a reduced ability to secrete bicarbonate ions, leading to decreased colonic motility and transit function, and fewer bowel movements. Other studies have found that constipated patients have a reduced ability to secrete mucus and bicarbonate, resulting in hard stools. International studies have shown that the intestinal secretion-promoting drug lubiprostone can significantly improve constipation symptoms in patients with constipation.
Common diseases
Rectal mucosal prolapse, rectocele, diabetes, hypothyroidism, hypopituitarism, hypokalemia, hypercalcemia, porphyria, amyloidosis, pheochromocytoma, glucagonoma, spinal cord tumor, Parkinson’s disease, multiple sclerosis, cauda equina tumor, congenital Hirschsprung’s disease, autonomic neuropathy, multiple sclerosis, systemic scleroderma, dermatomyositis, chronic obstructive pulmonary emphysema, uremia, lead poisoning, etc.
Seeking medical treatment
Outpatient indications
1. Defecation is difficult and laborious, and even requires the help of fingers. The feces are in the shape of sheep dung or pellets, and there is a persistent feeling of blockage in the rectum and anus and a feeling of incomplete defecation after defecation.
2. The number of bowel movements per week does not exceed 3 times; the bowel movement time is prolonged, and most patients have a bowel movement time of less than 15 minutes.
3. Constipation accompanied by obvious distension and pain in the lower left abdomen.
4. Constipation patients may experience blood dripping during or after defecation or anal pain.
5. Constipation accompanied by fullness in the upper abdomen, nausea and belching, etc.
6. Continuous inability to excrete feces and severe abdominal distension.
The above cases require prompt consultation with the gastroenterology department.
Treatment department
1. If you suspect slow-transmission constipation, you can go to the gastroenterology department for treatment.
2. If you suspect you have diabetes, you can go to the endocrinology department for treatment.
3. If you suspect a brain tumor, you can go to the neurology department for treatment.
4. If rectal lesions are suspected, you can go to the anorectal surgery department for treatment.
Medical preparation
1. Patients should try to eat a light diet a few days before the examination, avoid spicy food, and avoid drinking alcohol, staying up late, etc.
2. Make an appointment in advance and bring your ID card, medical insurance card, medical card, etc.
3. If you have had medical treatment recently, please bring relevant medical records, examination reports, laboratory test results, etc.
4. If you have taken some medicine to relieve symptoms recently, you can bring the medicine box with you.
5. Family members can be arranged to accompany the patient to seek medical treatment.
6. Patients can prepare a list of questions they want to ask in advance.
What questions might a doctor ask a patient?
1. How long have you been constipated? Has it gotten worse recently?
2. Do you have any other symptoms besides constipation, such as abdominal distension, bloody stools, hemorrhoids, dizziness, headache, excessive thirst, excessive drinking, excessive eating, etc.?
3. Do you have hemorrhoids? If so, how did you treat them?
4. Have you ever suffered from colorectal disease?
5. Is there anyone in your family who has colorectal cancer?
6. Do you like to eat animal fat? Do you rarely eat fruits, vegetables, or whole grains? Do you often eat spicy foods?
7. Do you smoke or drink alcohol? If so, how long have you been smoking or drinking? How much do you drink per day?
8. Do you exercise regularly?
What questions can patients ask their doctor?
1. Why do I have chronic constipation? What is the most likely cause?
2. Are my symptoms serious? What tests do I need?
3. Do I need to be hospitalized?
4. What treatment methods do I need now? Is it curable?
5. Are there any risks for me from these treatments?
6. What are the next steps in my diagnosis and treatment?
7. I have other diseases. Will this affect my treatment?
8. What should I pay attention to after returning home?
9. If medication is required, what are the usage, dosage, and precautions?
10. Do I need follow-up examinations? How often?
examine
Scheduled inspectionThe doctor will first perform a physical examination on the patient to gain a preliminary understanding of the patient’s general condition, and then selectively have the patient undergo intestinal motility and anorectal function tests, colonoscopy, blood tests, psychological examinations, etc.
Physical examinationPay attention to the patient’s nutritional status, whether the skin and mucous membranes are pale; whether the abdomen is distended, whether there are signs of ascites, pregnancy, or huge tumors, whether the liver and spleen are obviously enlarged; whether there are gastric, intestinal patterns and gastrointestinal peristaltic waves; whether there is abdominal muscle tension, tenderness, rebound pain, or gurgling sounds.
Laboratory tests
Patients suspected of having constipation caused by systemic diseases (such as thyroid disease, diabetes, connective tissue disease, etc.) should undergo relevant biochemical tests.
Imaging examinations
For patients aged >40 years and with alarm signs, colonoscopy and colonic barium contrast radiography can be performed to rule out intestinal diseases such as tumors and inflammatory reactions; patients with severe constipation and suspected intestinal pseudo-obstruction should have an abdominal plain film.
Other tests
1. Detection of intestinal motility and anorectal function
While these data are not essential for the clinical diagnosis of chronic constipation, they should be evaluated for patients with refractory constipation who have failed medication or before undergoing surgery to fully understand abnormalities in intestinal and anorectal function and structure. These tests include gastrointestinal transit testing, manometry, defecography, balloon expulsion testing, anal manometry combined with intracavitary ultrasound, and perineal nerve latency or electromyography.
2. Psychological survey
For patients with obvious anxiety and depression, relevant psychological investigations should be conducted, and the causal relationship between changes in psychological state and constipation should be analyzed and determined.
diagnosis
Diagnostic principlesDiagnosis is generally not difficult based on the patient’s medical history, clinical symptoms, and the results of auxiliary examinations. During the diagnostic process, it is necessary to check for conditions such as slow-transit constipation, rectocele, rectal mucosal prolapse, puborectalis syndrome, and pelvic floor spasm.
Diagnostic basis
International Rome III diagnostic criteria for constipation
1. Two or more of the following symptoms should be included:
(1) Straining during at least 25% of bowel movements.
(2) At least 25% of bowel movements are hard or ball-like stools.
(3) At least 25% of bowel movements have a feeling of incomplete defecation.
(4) At least 25% of bowel movements are accompanied by anorectal obstruction.
(5) At least 25% of bowel movements require manual assistance (such as finger defecation, pelvic floor support).
(6) Fewer bowel movements per week.
2. Soft stools are rare without laxatives.
3. Does not meet the diagnostic criteria for IBS. Symptoms must have occurred for at least 6 months before diagnosis, and the above criteria must have been met for the past 3 months.
Patients with constipation should undergo a detailed medical history and a comprehensive physical examination. Severe symptoms should be followed by a barium enema, colonoscopy, and biochemical studies to exclude organic pathology. A prolonged course of illness without improvement often indicates functional or idiopathic constipation.
Differential diagnosis
1. Slow-transmission constipation
This condition is constipation caused by decreased intestinal transit capacity. It’s more common in young women, with decreased bowel movement frequency, typically occurring every 2-3 days or longer. This is often accompanied by abdominal distension and discomfort. Colonic transit time measurements may reveal slowed colonic transit or delayed sigmoid and rectal transit.
2. Rectocele
This condition is more common in women. Due to a weakened rectovaginal septum, the vagina protrudes into the vagina under the pressure of feces during defecation, causing constipation. Dysfunction is a prominent symptom of this condition. Digital rectal examination is the primary diagnostic tool, as it can detect areas of weakness and looseness in the anterior rectal wall. Defecation radiography can directly demonstrate the width and depth of the rectocele.
3. Rectal mucosal prolapse
Due to laxity and prolapse of the rectal mucosa, intussusception occurs during defecation, obstructing the upper opening of the anal canal and causing difficulty in defecation. The greater the straining, the more severe the obstruction. Defecation radiography can reveal a funnel-shaped image on a lateral rectal radiograph during straining. Digital rectal examination can reveal laxity of the lower rectal mucosa or accumulation of mucosa within the intestinal lumen.
4. Puborectalis syndrome
Spasmodic hypertrophy of the puborectalis muscle causes outlet obstruction, leading to constipation. This condition is characterized by progressive, long-term, and severe difficulty defecating. Digital rectal examination may detect increased anal canal tone; anal manometry may reveal elevated resting and systolic pressures; anal electromyography may reveal paradoxical electrical activity in the puborectalis muscle and external sphincter; and colon transit function testing may reveal significant rectal retention.
5. Pelvic floor spasm syndrome
During normal defecation, the puborectalis muscle and external anal sphincter relax, widening the anorectal angle and relaxing the anal canal, facilitating stool passage. If these muscles fail to relax or even contract during defecation, they can obstruct the intestinal outlet and cause dyspnea. Digital rectal examination is a key diagnostic tool for this condition, as it can palpate the hypertrophic, spasmodic internal sphincter. Rectal manometry reveals elevated resting anal canal pressure. Defecography reveals that the anorectal angle does not widen, and may even narrow, during straining.
treat
Expected treatmentChronic constipation can be caused by many factors in daily life. Therefore, doctors generally actively investigate the cause and then provide personalized treatment based on the patient’s specific situation. Doctors will ask patients to pay attention to their diet and daily habits and prescribe appropriate medications when necessary. For patients who do not respond to the above non-surgical treatments, doctors will consider appropriate surgical treatment based on the actual condition.
Treatment
1. Non-surgical treatment
Conservative treatment should be initiated, such as increasing fiber intake and developing regular bowel movements. Laxatives, suppositories, or enemas may be used as adjuncts if necessary. If conservative treatment is ineffective, surgical treatment may be considered.
2. Surgical treatment
Surgical treatment targets two main types of defects in stool transport and excretion: outlet obstructive constipation requires treatment tailored to the cause of the obstruction, while slow-transit constipation requires resection of the colon, which lacks the ability to transport stool. Sometimes both causes coexist, resulting in mixed constipation, requiring careful consideration of surgical options.
(1) Colectomy: It is mainly used to treat slow-transit constipation of the colon and has a positive effect. It mainly includes ① total colectomy and ileorectal anastomosis; ② subtotal colectomy and cecorectal anastomosis.
(2) Rectocele repair: used to treat rectocele. There are two types of repair: closed repair and open repair. The purpose of the surgery is to repair the defective weak area of the rectovaginal septum. In clinical practice, the Sehapayah procedure is more commonly used. The method is to make a longitudinal incision in the anterior midline of the rectum above the dentate line, deep into the submucosal layer, and after freeing the mucosal flap on both sides, use catgut to suture the edges of the levator ani muscles on both sides with 3 to 5 interrupted stitches, and then suture the mucosal incision.
(3) PPH surgery (stapled hemorrhoidectomy): It can also be used for the surgical treatment of rectal mucosal prolapse.
(4) Rectopexy: Mainly used to treat rectal prolapse. The methods include transanal rectal mucosal fixation and transabdominal rectopexy.
(5) Partial puborectal muscle resection: used to treat puborectal muscle syndrome.
Related drugsPhenolphthalein tablets, enema, castor oil, etc.
daily
Nursing principles
1. Encourage patients to drink plenty of water, including a cup of warm water or salt water every morning. Eat more foods rich in crude fiber, such as celery, fungus, and onions. Fruits and other high-residue foods, such as bamboo shoots, flour, and oat bran, can also help with bowel movements.
2. Cultivate the habit of regular bowel movements in patients. Even if the patient has no urge to defecate, he should insist on squatting for 10 minutes regularly.
3. Patients with poor general health or weak abdominal muscles should increase their activities and physical exercise. They can also use the defecation movement, that is, the contraction and expansion movement during normal defecation, to exercise the contraction of the levator ani muscles.
prevention
Preventive measures
1. Adjustment of daily diet
(1) Avoid eating too refined food, and avoid partial eclipse. Increase the fiber content in your diet, such as whole grains, vegetables (white radish, leek, raw garlic, etc.), and fruits (apples, red dates, bananas, pears, etc.). For example, eat one apple on an empty stomach in the morning and evening, or one to three bananas before each meal.
(2) Drink enough water. The daily water intake is about 2000 ml. Drinking 1-2 cups of light salt water, boiled water, or honey water on an empty stomach every morning can prevent and treat constipation.
(3) Consume an appropriate amount of vegetable fats in your diet, such as sesame oil, soybean oil, etc., or eat nuts rich in vegetable oils, such as walnuts and sesame seeds.
(4) Eat appropriate amounts of foods that help lubricate the intestines, such as honey, yogurt, etc.
(5) You can regularly eat some medicinal porridges that can prevent and treat constipation, such as sesame porridge, walnut porridge, spinach porridge, sweet potato porridge, etc.
(6) Eat less strongly irritating foods that increase heat, such as chili peppers, curry and other condiments, and avoid drinking alcohol or strong tea.
2. Lifestyle adjustment
(1) Develop a habit of regular bowel movements. It is best to have a regular bowel movement after breakfast every day, based on the “gastro-colonic reflex”. It is easier to have a defecation reflex after a meal. As long as you persist in having regular bowel movements, you can gradually establish a conditioned reflex of the defecation reflex, and after you get used to it, you will be able to have a bowel movement on time.
(2) Develop the habit of concentrating on defecation. Avoid reading, listening to the radio, smoking, etc. while in the toilet. Eliminate all bad habits that distract you from the urge to defecate and prolong your bowel movement. Elderly people should use sit-down toilets to prevent themselves from squatting for long periods of time and straining to defecate, which can lead to collapse.
(3) Do not ignore the urge to defecate. If you often ignore the urge to defecate or force yourself to endure it, the feces will stay in the intestines for too long, resulting in dry stools, which can cause or aggravate constipation.
(4) Live a regular life, keep a good mood, participate in physical labor appropriately, and exercise regularly, especially focusing on abdominal muscle exercises, such as sit-ups, leg curls, squats, stand-ups, running, cycling, skipping rope, etc. These can strengthen abdominal exercises, promote gastrointestinal motility, help promote bowel movements, and avoid sitting, lying, or standing for long periods of time.
(5) Self-abdominal massage. A simple method is to lie on your back, with your abdomen as the center, and use your palms to massage the abdomen in a clockwise direction, applying appropriate pressure. Do this once a day, morning and evening, for about 10 minutes each time. This can promote digestive tract activity and maintain smooth bowel movements.
(6) Take care of yourself by regularly doing gymnastics, anal contraction exercises, qigong, tai chi, etc.