A Prospective, Descriptive Study to Assess the Effect of Dietary and Pharmacological Strategies to Manage Constipation in Patients with a Stoma
The term constipation with regard to patients with a stoma is defined as impaired bowel movements associated with increased stool consistency or long periods without bowel movements that lead to discomfort, flatulence, and abdominal pain. Information about constipation in patients with a stoma is limited. A prospective, descriptive study was conducted among patients attending ostomy and proctology outpatient clinics in Poznan, Poland between January 2011 and December 2014 to assess the role of dietary and pharmacological strategies in the management of constipation in patients with a stoma.
Patients were included if they experienced a 3-day period without bowel movements leading to abdominal discomfort and bloating. Patients who were terminally ill from neoplastic disease or could not provide informed consent for study participation were not eligible to participate. Patients underwent 3 evaluations 3 months apart: the first assessed problems with passing stool through the stoma, at which time patients were told to increase fiber and fluid intake. During the next 2 visits, patients were asked if their symptoms had improved. If dietary changes were not successful, first-line pharmacological interventions were suggested (laxatives, osmotic agents, and probiotics). If no improvement was reported during the third assessment, second line pharmacologic therapy (eg, stimulant laxatives) were prescribed. Of the 405 patients initially assessed for participation, 331 met the initial screening criteria and were scheduled for follow-up. Of those, 93 (28%) had constipation; 50 (15%) required a surgical referral for morphological stoma changes and 43 (12.9%) met the study inclusion criteria for dietary recommendations. Almost all (42) had a colostomy and most (28) had a history of stoma creation due to diverticular disease. Twenty-five (25) men and 18 women (average age 55.9 ± 9.3 years) received dietary recommendations during the first visit. Diet modifications were effective and sufficient to resolve the problem with constipation in more than half (24) of the patients. Among the remaining 19 patients, only 2 did not improve after using first-line or second-line pharmacological management strategies. One patient required emergency surgery due to complicated colonic diverticulosis (perforation). The results of this study suggest constipation among patients with a stoma can be associated with morphological stoma changes and in the absence of morphologic changes the majority of patients respond well to a change in diet. Additional studies are needed to increase understanding about the incidence and optimal management strategies of constipation in persons with a stoma.
One of the goals of modern colorectal surgery is to preserve the anal sphincters and maintain physiological colonic transit. However, in some clinical situations, creating a stoma is unavoidable, recommended, or crucial to save a patient’s life. The creation of an artificial anus may impair overall quality of life. Patients with stomas may experience certain disorders associated with colonic transit, including chronic constipation. In their technical review, Bharucha et al1 found the overall median prevalence of constipation in the general population is 16% (range 0.7%–79%) in adults and 33.5% in adults 60 to 101 years old. Most, but not all, studies suggest the prevalence of constipation in the general population is higher in the non-Caucasian population than in the Caucasian population and also higher in women (median female-to-male ratio of 1.5:1).2 A cross-sectional survey3 conducted in various settings found general health, mental health, and social functioning were impaired in patients with constipation as compared to healthy patients in the control group, particularly among hospitalized patients in comparison to patients in the community.
The term constipation is rarely used with regard to patients with a stoma. It is difficult to quantify the frequency of bowel movements in this group of patients. Constipation among patients with a created stoma is defined as impaired bowel movements associated with increased stool consistency or long periods without bowel movements that lead to discomfort, flatulence, and abdominal pain and refers almost exclusively to patients with a colostomy. Constipation rarely occurs in patients with an ileostomy due to the liquid consistency of intestinal content secreted by ileostomy. However, ileostomy patients may experience food blockage proximal to the ostomy site, which can occur because the ileal lumen is <3 cm in diameter and potential exists for further narrowing at the point where the bowel passes through the fascia/muscle layer. If a patient consumes large amounts of insoluble fiber, the undigested fiber may create an obstructing mass (bezoar). Common products that can cause obstruction include popcorn, coconut, mushrooms, black olives, stringy vegetables, unpeeled fruit, dried fruit, and meats with casings. Food blockage prevention instructions advise adding potential causative products 1 at a time in small amounts, chewing them thoroughly, and monitoring the response.4
Few publications address constipation in persons with a stoma. In the authors’ experience, patients with a stoma usually have an increased risk of constipation if they present with symptoms of constipation before stoma creation. In their cross-sectional cohort study, Vironen et al5 explored the effect of bowel and urogenital dysfunction on social functioning. Quality of life after rectal cancer surgery was not necessarily decreased as compared to the general population; Veronen et al5 and Rauch et al6 noted a permanent colostomy is not always the primary factor that disrupts a person’s quality of life.
Gallegos-Orozco et al’s7 review of the literature focused on the epidemiology of chronic constipation, diagnostic approaches, and nonpharmacological as well as pharmacological management of chronic constipation in a general population of elderly patients. According to the authors, certain risk factors for constipation affect the general population; these factors also may be applied to patients with a colostomy.
Previously diagnosed chronic constipation. The incidence rate of constipation is estimated to be between 2% to 28% in the general population. The most common risk factors include insufficient fiber intake and lack of physical activity. Other reasons include use of drugs that inhibit normal peristalsis, metabolic and endocrine disorders, neurological diseases, and congenital and acquired diseases causing intestinal obstruction (adhesions, obstructive benign and malignant colorectal tumors, or inflammatory bowel disease). Chronic constipation is also one of the important risk factors for diverticulosis. Complications of diverticulosis are serious and management usually includes creating a stoma (Hartmann procedure). Following the surgery, a short-term improvement in constipation is usually observed in this group of patients but usually reappears.8
Stoma creation in a patient diagnosed with colorectal cancer. In this group of patients, constipation is usually associated with either progression of the primary disorder (colorectal cancer) or impaired colonic patency proximally to the site of the stoma creation. It is also caused by the use of opioid analgesics that significantly decrease colonic transit.9 Currently, the administration of opiates in Poland is ordered by a Palliative Outpatient Care Unit; prokinetic drugs are routinely prescribed with opiates but not all patients are well informed about the need for prokinetic drug administration.7
Patient age. Patients 60–70 years most frequently require stomas due to the prevalence of 2 major indications for their creation: colorectal cancer and diverticulitis.10 Slow colonic transit in general and varying comorbidities such as neurological, cardiovascular, and metabolic disorders, as well as reduction of physical activity and insufficient intake of daily fluids, result in an increasing tendency for constipation.1
Use of drugs. Elderly people usually are prescribed various medications to manage their comorbidities. Some medications may exacerbate constipation as a side effect. It is important to note opioid analgesics, antispasmodic drugs, medications containing calcium (antacids, dietary supplements), iron supplements, antiemetics, calcium channel blockers (eg, verapamil), some diuretics (furosemide), antihistamines (diphenhydramine), diastolic (anticholinergic drugs), psychotropic drugs (eg, chlorpromazine), medications used for Parkinson’s disease, tricyclic antidepressants (eg, amitriptyline), and nonsteroidal anti-inflammatory drugs (eg, ibuprofen) may influence constipation.7
Inappropriate diet and insufficient intake of liquids. In Proctology Outpatient Clinics, the authors observed patients who are not well-educated about stoma management try to reduce the frequency of emptying the stoma bag and formation of loose stools, thinking such actions may reduce the leak beneath the plate of the stoma. According to these mistaken beliefs, patients restrict fluid and fruit intake, achieving the desired effect for only a short period of time. However, chronic constipation may be a long-term result.7
Constipation in patients with a stoma also can lead to further complications. In their clinical review, Basilisco and Coletta11 note the most common problems in addition to constipation are flatulence, abdominal pain, peristomal hernia, prolapse of the stoma, and diverticulosis of the spared part of the colon. Appropriate diagnostic and therapeutic management of patients with constipation and stoma presence may substantially improve quality of life.
The purpose of this study was to evaluate the effect of dietary changes and pharmacological management on constipation in patients with a stoma.
Material and Methods
Patients. A prospective, descriptive study was designed in accordance with the Helsinki declaration and the regulations of the Ethics Committee of Poznan University of Medical Sciences. Patients were recruited from 2 Ostomy and Proctology Outpatient Clinics in Poznan, Poland. Patients were eligible to participate if they believed they were constipated. Because there is a lack of established criteria for the diagnosis of constipation in patients with a stoma, for the purpose of this study the same criteria for constipation were used as for patients without a stoma — that is, constipation was considered a 3-day period without bowel movements leading to discomfort in the abdomen, bloating, and abdominal pain. Patients who met the above criteria for the diagnosis of constipation were eligible for study participation. Patients were excluded if they were terminally ill from neoplastic disease, did not provide informed consent for study participation, or exhibited limited awareness and decreased mental status (neurological disorders, alcoholism, and/or mental disorders).
Procedure. The study was conducted by surgeons working in Proctology Outpatient Clinics between January 2011 and December 2014 and involved 3 assessment visits. During the initial visit, patients were informed about the aim of the study and screened for study eligibility. The primary focus was on the episodes of constipation experienced by the patients and symptoms such as abdominal discomfort, bloating, and abdominal pain. Every patient with a stoma admitted to the Outpatient Clinic was routinely evaluated by a surgeon. Patients were advised to report to the outpatient clinic every 3 months for follow-up visits.
First visit. During this visit, the patient’s medical history (reason for stoma creation, comorbidities, family history, surgeries) and other data (age, dietary habits, addictions) were collected in individual charts. Patients were asked about their problems with passing stool through the stoma. Patients who demonstrated significant dysfunction of the stoma and reported difficulties with emptying the stoma were sent for further surgical investigation; patients requiring surgical treatment were excluded from the study. Patients diagnosed with constipation received detailed information about dietary and lifestyle modification recommendations; the first line of conservative treatment for constipation in patients with a stoma was diet modification. Based on the current guidelines of the American Society for Parenteral and Enteral Nutrition (ASPEN)12 and the American Dietetic Association (ADA),13 recommended fiber intake of at least 14 g per 1,000 kcal should be consumed each day (20–35 g/day according to National Academy of Science Institute of Medicine14), and fluid intake should be approximately 3 L per day. Patients were provided verbal instructions and written information that advised them to reduce the volume of each meal and increase the total number of daily meals. Reduction of monosaccharaides also was recommended.12-14 Patients also were informed about lifestyle modification recommendations, including daily exercise (for example, walk at least 30 minutes once a day), hydration (fluid intake), and reserving enough time for bowel movements.15
Second visit. During the next visit, the effectiveness of the dietary recommendations was evaluated. Subjective assessment of symptom improvement was ascertained with a single closed-end question requiring a Yes/No answer: Did you observe adequate relief of constipation symptoms related to abdominal pain or discomfort within the past 3 months? In the case of sufficient efficacy of the diet recommendations, the existing management was maintained. In the absence of clinical response to previous recommendations, pharmacological management was implemented and included bulk-forming laxatives (psyllium seed: 1–2 tablespoons per day), osmotic agents (lactulose: 15–45 mL per day), and probiotics (combined products containing selected strains of live micro-organisms such as Lactobacillus and Bifidobacterium, 1 capsule per day).
Third visit. Patients were asked about the effectiveness of pharmacological management. In cases of sufficient efficacy of pharmacological recommendations, the existing management was maintained. In the absence of clinical response to previous recommendations, additional prokinetics were implemented (metoclopramide or/and itopride hydrochloride: 3 tablets per day). Moreover, provision of a glycerin suppository and/or stoma irrigation was performed periodically when indicated. The study design is shown in Figure 1.
Data collection and analyses. Information about constipation and its symptoms were collected by the patients on spreadsheets and then analyzed by a nurse during follow-up visits. The described data are presented as mean ± standard deviation (mean ± SD).
From the initial pool of 405 patients from the Ostomy and Proctology Outpatient Clinics enrolled in the study, 74 patients were excluded because they did not fulfill study inclusion criteria. The remaining 331 patients with a stoma (146 women, 185 men; average age 61.3 ± 12.7 years) were included for the first visit. Of those, 273 patients (82.5%) had an end stoma and 58 (17.5%) had a loop stoma; 132 stomas (40%) were formed due to complications of diverticular disease, 114 (34%) because of rectal cancer, 35 (10.5%) due to inflammatory bowel disease, 23 (7%) because of other cancers, 14 (4.2%) were due to injuries, and 13 (3.9%) due to a rectovaginal fistula (see Table 1).
At first follow-up visit, 93 (28%) patients with a diagnosis of constipation qualified for further investigation. Among them, constipation was associated with late stomal complications16 such as a stomal stenosis or prolapse and parastomal hernia in 50 patients (54% of patients with constipation). Late complications are defined as problems occurring after the period of physiological adjustment, which is usually 6–10 weeks. In a retrospective analysis, Park et al17 noted 93% of late complications occurred within the first 6 months. In the current group of patients, the diagnosis of stomal complication usually was determined during the first follow-up visit. In the authors’ hospital, the first routine visit after stoma creation is 4 weeks after surgery; earlier visits are scheduled when there are stoma complications. Thus, 43 patients (46% of patients with constipation) — 42 with a colostomy and 1 with an ileostomy — presenting with constipation were included into the final stage of the study and scheduled for follow-up visits 2 and 3. These included 18 women and 25 men (average age 55.9 ± 9.3 years). Of those, 28 had a stoma secondary to complications of diverticular disease, 6 had a history of rectal cancer, 2 had inflammatory bowel disease, 3 had other cancers, 3 had stoma surgery following injuries, and 1 had a rectovaginal fistula.
At the second follow-up visit, lifestyle and diet modifications were effective and sufficient to resolve the problem with constipation in more than half (24) of the patients. In 19 patients, it was necessary to introduce pharmacological management. During the third follow up visit, 17 of the 19 patients reported the pharmacological regimen was successful. In 2 patients, both lifestyle and diet modification as well as pharmacological management were ineffective. One patient required urgent surgery due to complicated colonic diverticulosis (perforation), and a right hemicolectomy with ileostomy procedure was performed. Another patient did not agree to surgery despite severe abdominal pain (see Table 1 and Table 2).
Based on the American Gastroenterological Association technical review1 on constipation and American Gastroenterological Association3 medical position statement on constipation, along with the authors’ experience and the results of this study, an algorithm for managing constipation in patients with a stoma was proposed (see Figure 2). It has not been tested as yet. Key points of the algorithm include: assessing the entire colon (particularly in patients with a history of cancer); considering use of a rectal dilatator (especially in case of moderate stomal stenosis); avoiding use of an excessive amount of paraffin and vegetable oil (patients often report problems with leakage beneath the stoma plate); modifying laxative dosage to avoid too strong an effect; particular care with patients with a stoma created due to Crohn’s disease; and considering MR enterography due to the high risk of changes in the ileum terminale.
As far as the authors are aware, this study is the first to assess the effectiveness of dietary and pharmacological management of constipation in patients with a stoma, including the effect of recommended dietary behaviors on the treatment of obstruction in patients with a stoma and patients’ subjective impression of symptom improvement over 3 months.
The problem of constipation in patients with a stoma is challenging due to the fact it is difficult to determine stool frequency and output. Approximately 28% of the patients with a stoma treated in the Ostomy and Proctology Outpatient Clinics had constipation on the first follow-up visit 4 weeks post surgery. In this group, 54% of patients experienced constipation due to problems with the stoma such as hernia, prolapse, or narrowing. Physical examination during the first follow-up visit focused on the morphological changes within the stoma and showed almost 15% of all patients with stomas presented with structural stomal disturbances. In the authors’ opinion, this is a relatively high percentage of patients who were referred for further surgery and required further analysis to eliminate the need for reoperation in the future.
In 46% of patients (13% of the entire study group), constipation was associated with impaired motility, not morphological impairment; 95% of these patients reported improvement of their constipation symptoms after implementing dietary recommendations or pharmacological treatment. It should be emphasized that patients usually do not obtain sufficient support from primary care physicians to establish a regular pattern of bowel movement. In the authors’ experience, the discomfort associated with constipation in the presence of a stoma (bloating, abdominal pain, flatulence, and the like) is frequently considered a side effect of having a stoma. In the authors’ department, a stoma nurse instructs patients how to deal with potential stoma problems (ie, care and problems with bowel movements) before hospital discharge. The authors have observed this is not standard care in most of the surgical departments in Poland (small, not clinical hospitals), which do not have stoma nurses. As such, after discharge, patients use an Outpatient Clinic such as the authors’.
Results of the current study are difficult to compare with any other studies because of limited data in the literature regarding constipation in stoma patients. Data can be compared only to research studies analyzing constipation in the general population. Current results were similar to Bharucha et al’s1 review: constipation affected 16% (range 0.7%–79%) adults overall and 33.5% adults ages 60 to 101 years. The current study was conducted among a Caucasian population and involved more men who experienced constipation than women.
No clear guidelines exist for endoscopy surveillance after colorectal cancer in patients with a stoma; care is based on individual features of patients and may differ between surgical centers.18-20 In this study, 50 of the 93 patients with constipation had morphological stoma changes requiring surgical follow-up.
The results of this study confirm the importance of dietary modification for constipation in patients with a stoma. Approximately 55.8% of patients with constipation and without any stomal morphological changes reported improvement or complete resolution of symptoms after implementing dietary modifications. These results suggest the problem of constipation in patients with a stoma often can be solved at the primary level of care and dietary recommendations should be the first line of treatment.21
Of the 19 patients who required first-line pharmacologic therapy, the vast majority (14% to 74%) improved. Flatulence associated with inappropriate diet is a common problem in patients with constipation. Probiotics and prebiotics should be considered in dietary recommendations. According to Quigley22 and Hamer et al’s23 reviews of the literature, adequate intake of pro- and prebiotics positively influences the intestinal mucosa, resulting in normalization of intestinal transit and the proper secretion of mucus by goblet cells of the large intestine. Moreover, these products contribute to appropriate and balanced intestinal flora. Both pro- and prebiotics may be delivered in natural food sources (eg, yogurt) or dietary supplements (eg, butyric acid or combined products of probiotics).24,25
Patients in this study who did not improve with dietary changes alone also received bulk-forming laxatives. Some clinical studies26 indicate the benefit of bulk-forming laxatives (eg, psyllium, methylcellulose), softeners (eg, surfactants), and osmotic agents (eg, lactulose). However, long-term use of these laxatives may cause flatulence, diarrhea, and electrolyte disturbances. Moreover, a possibility of a drug tolerance for this group of medications is well known and their high sugar content can be problematic for some patients.27 Of the 5 patients who did not report improvement after trying dietary changes and first-line pharmacologic therapy, 3 reported improvement after using stimulant laxatives. The mechanism of action of these agents includes increased electrolytes and water secretion across the intestinal mucosa and enhanced intestinal motility by stimulating intramural ganglia. Unfortunately, a multicenter, randomized controlled trial28 has shown intestinal peristaltic stimulation may cause abdominal pain and flatulence. In addition, a review of diverticular disease29 has shown long-term use of a stimulant laxative may ultimately lead to atony of the intestines with a characteristic endoscopic feature of “leopard skin.” At the authors’ clinic, use of stimulant laxatives is generally not recommended because they can cause abdominal pain, especially in a patient population with a history of surgery and potential adhesions.
In this study, stoma irrigation is not recommended as a measure to address constipation, in part because it is not commonly recommended in the clinics. However, results of a prospective, descriptive evaluation30 showed it can be an effective way to regulate bowel movements in patients with constipation.
Diverticular disease. Constipation among ostomy patients was most commonly observed in patients with a history of stoma creation due to diverticular disease. Fifty-four (54) of the 132 patients (40.1%) with diverticular disease had constipation, constituting 58% of the entire study group. Alterations in colonic motility have been implicated in the development of diverticular disease, but it is not known whether constipation and impaired motility cause diverticulosis or are a result of changes in the large intestine wall structure.31
Implementation of dietary recommendations and pharmacological recommendations if needed resolved problems with constipation in almost all patients. The symptoms of only 2 patients (4.6% of patients with diagnosed constipation with exclusion of morphological stomal changes) did not improve.
The current study has several limitations. A larger sample size would be beneficial, especially in the context of comorbidities that might influence constipation. Diagnostic criteria of constipation in patients with a stoma are based on clinical symptoms; they are subjective and reflect a physician’s individual assessment and experience and as such are difficult to standardize and compare. Although the question for subjective clinical symptom improvement seemed to be practical, it has not been validated for constipation. A larger study with multi-institutional input would be valuable. A longer observation period is necessary to assess whether the duration of the stoma has an impact on stoma constipation.
The problem of constipation in patients with a stoma often is not discussed but can be an indication of morphological changes and, similar to patients without a stoma, have negative effects. In this study, almost half of all patients who presented with constipation required further evaluation to address morphological stoma changes. Constipation symptoms in the majority of patients (55%) who did not require further evaluation responded well to dietary changes. Constipation resistant to conservative (nonsurgical) interventions occurred only in 2 patients (stoma created because of complications of diverticular disease); both patients qualified for surgery (colectomy) because of colonic inertia, but they refused that method of treatment.
The creation of a stoma may not solve problems with constipation. Using approaches known to help persons without stomas, along with educating stoma nurses and patients on appropriate stoma care, may help provide relief from this problem.
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Potential Conflicts of Interest: none disclosed
Dr. Krokowicz, Dr. Bobkiewicz, and Dr. Borejsza-Wysocki are surgeons and Ms. Kuczynska is a dietitian, Department of General, Endocrinological Surgery and Gastroenterological Oncology; Dr. Lisowska is a pediatrician, Chair of Pediatrics, Department of Gastroenterology and Metabolism; Dr. Skowronska-Piekarska and Dr. Paszkowski are surgeons, Department of General, Endocrinological Surgery and Gastroenterological Oncology; Dr. Walkowiak is a pediatrician, I Chair of Pediatrics, Department of Gastroenterology and Metabolism; and Dr. Drews and Dr. Banasiewicz are surgeons; Department of General, Endocrinological Surgery and Gastroenterological Oncology, Poznan University of Medical Sciences, Poznan, Poland. Please address correspondence to: Lukasz Krokowicz, MD, Department of General, Endocrinological Surgery and Gastroenterological Oncology, Poznan University of Medical Sciences, 49, Poznan, Poland; email: firstname.lastname@example.org.