Multicenter Randomized Trial of 10-French versus 11.5-French Plastic Stents for Malignant Biliary Obstruction.

Background. There is little prospective data on whether bigger plastic stents are better for patients with malignant biliary obstruction with jaundice. Goals. Multicenter prospective study to compare technical success, clinical response, stent occlusion, and patient survival in patients with malignant biliary obstruction randomized to 10-French or 11.5-French plastic stent. Study. Patients with malignant biliary obstruction were randomized to 10-French or 11.5-French biliary stents. Patients were prospectively assessed for stent occlusion, stent-related interventions, hospital stay, and change in bilirubin. Main outcome measurements included technical success, clinical response, rates of stent occlusion, and survival. Results. 234 patients (47 hilar and 187 common bile duct strictures) were randomized. Outcomes were similar for the 10-French and 11.5-French groups (technical success 99.1% versus 97.4%, P = 0.37). Overall, median stent survival was 213 days, but there was no statistically significant difference in stent survival between 10-French and 11.5-French stents (149 versus 258 days, P = 0.16). Stent survival was significantly longer when placed for common bile duct versus hilar strictures (231 versus 115 days, P = 0.049). Conclusions. The theoretical advantage of improved bile flow for the 11.5-French stent does not translate into more prolonged patency, better clinical response, and longer patient survival than the 10-French stent.

Effect of endoscopic stenting of malignant bile duct obstruction on quality of life.

BACKGROUND AND GOALS: Endoscopic stent insertion is considered the method of choice for palliation of malignant bile duct obstruction (MBDO). However, it can cause complications and requires periodic stent exchanges. Although endoscopic stenting is clearly indicated for relief of cholangitis or refractory pruritus, its role in patients with jaundice alone is less clear. Endoscopic stenting for this relative indication might be justified, if there is a significant improvement in quality of life (QOL) of such patients. The aim of our study was to determine whether endoscopic stenting for MBDO results in improved QOL. PATIENTS AND METHODS: Patients undergoing endoscopic retrograde cholangiopancreatography for MBDO and participating in a randomized trial comparing patency duration of 10 and 11.5-Fr biliary plastic stents, completed the Functional Assessment of Cancer Therapy-General questionnaire at baseline, at 1 month after stent insertion, and at 180 days after stent insertion. RESULTS: A total of 164 patients answered the QOL questionnaire at baseline, 95 patients answered the questionnaire at 30 days, and 54 patients answered the questionnaire at 180 days after stent insertion. Endoscopic biliary stenting resulted in a statistically significant improvement in overall score of QOL, and different aspects of QOL such as physical, emotional, and functional well-being. There was a statistically significant improvement in most of the symptoms specific for MBDO at 30 and 180 days after stenting. CONCLUSIONS: Endoscopic stenting significantly improves QOL in patients with MBDO, and, therefore, is an appropriate part of palliative treatment in this patient population.

OTC polyethylene glycol 3350 and pharmacists' role in managing constipation.

OBJECTIVES: To define constipation, assess the pharmacist's role in identifying and treating constipation, and review clinical evidence for the efficacy, safety, and tolerability of polyethylene glycol (PEG) 3350 (MiraLAX-Merck Consumer Care), an osmotic laxative now available over the counter (OTC), across a variety of patient populations routinely encountered in pharmacy settings. DATA SOURCES: Systematic PubMed search of the primary literature for constipation treatment guidelines and clinical trial results for PEG 3350. DATA SYNTHESIS: Pharmacists have a unique role in assisting patients with identifying and managing constipation. Multiple controlled clinical trials have established the efficacy, safety, and tolerability of PEG 3350 at its recommended dose of 17 g once daily. On the basis of this evidence, various professional groups have recommended PEG 3350 for use in improving stool frequency and consistency in patients with constipation. PEG 3350 is approved for short-term use, including treatment of constipation caused by medications. CONCLUSION: Pharmacists can play an important role in managing constipation with OTC agents. Compared with other available OTC agents, PEG 3350 can be recommended to patients suffering from constipation on the basis of a large body of clinical evidence supporting its efficacy and safety, as well as the high patient acceptance shown for its palatability and once-daily dosing.

Long-term safety and effectiveness of lubiprostone, a chloride channel (ClC-2) activator, in patients with chronic idiopathic constipation.

BACKGROUND: Lubiprostone helps relieve constipation in short-term 4-week studies. There are limited data on long-term pharmacological treatment with lubiprostone for chronic idiopathic constipation. AIMS: To examine the long-term safety and effectiveness of lubiprostone in patients with chronic idiopathic constipation. METHODS: In this prospective, multicenter, open-labeled trial, 248 patients aged ≥18 years with chronic idiopathic constipation were directed to take lubiprostone 24 mcg BID as needed for 48 weeks. Patients were allowed to decrease the dose in response to the perceived severity of constipation and need for relief. Hematology and chemistry profiles and assessment of constipation symptoms and its severity were performed at all visits. Adverse events (AEs) were recorded. RESULTS: Of the 248 patients who entered the trial, 127 (51%) completed the trial. A dose reduction was observed in 17% of the patients, resulting in an average study medication exposure across the study of approximately 1.7 capsules (or approximately 40.8 mcg) per day. The most common treatment-related AEs were nausea (19.8%), diarrhea (9.7%), abdominal distension (6.9%), headache (6.9%), and abdominal pain (5.2%). No deaths were reported and of the 16 reported serious AEs, one was considered possibly treatment related. Average changes in serum electrolytes were not clinically relevant at any time point during the study. On average, lubiprostone significantly (p < 0.0001) reduced patient-reported constipation severity, abdominal bloating, and abdominal discomfort across 48 weeks when compared to baseline. CONCLUSIONS: During this 48-week open-label study, lubiprostone was well tolerated. Bowel symptoms consistently improved over 48 weeks in adult patients with chronic idiopathic constipation.

Over-the-counter laxative polyethylene glycol 3350: an evidence-based appraisal.

OBJECTIVE: To explore the clinical dimensions of chronic constipation and the role played in its treatment by laxatives in general and by polyethylene glycol 3350 (MiraLAX * ) in particular. * MiraLAX is a registered trade name of Schering-Plough HealthCare Products, Inc., Memphis, TN, USA, a subsidiary of Merck & Co., Inc. RESEARCH DESIGN AND METHODS: Published reports of clinical trials involving polyethylene glycol 3350, together with published articles examining the epidemiology, demographics, etiology, evaluation, and management of chronic constipation, were identified in a literature search through November 2009 using PubMed. Congress proceedings and guideline databases of leading national and international gastroenterology associations were also explored for relevant recommendations and evaluations. MAIN OUTCOME MEASURES: Constipation, often defined differently by patients and physicians, is typically associated with excessive straining, hard stools, infrequent bowel movements, and sensations of incomplete evacuation. Specific criteria are available to aid physicians in making a diagnosis of functional constipation. Initial patient management typically involves dietary and lifestyle changes, although this approach is supported by limited clinical evidence and is often a source of considerable patient frustration. A laxative is needed when these changes do not sufficiently relieve constipation. Multiple agents from several different laxative classes are available, differing in mechanism of action, safety and efficacy profile, and clinical evidence supporting their use. RESULTS: Twenty-one studies involving a total of 1949 patients were included in the overall review of polyethylene glycol 3350. Fifteen studies used randomized designs, eight were comparative trials, seven were conducted in pediatric populations, and three had elderly components. LIMITATIONS: Limitations of this review included lack of comparability among the various patient populations described; focus on a single agent; potential publication bias; non-systematic review. CONCLUSIONS: Polyethylene glycol 3350, an osmotic laxative available over the counter, has been shown to be safe and effective in treating chronic constipation in children and adults, including the elderly, across multiple clinical trials, with a safety profile comparable to that of placebo. Polyethylene glycol 3350 received a grade A recommendation for improving stool frequency and consistency from the American College of Gastroenterology Task Force on Chronic Constipation.

Efficacy and safety of lubiprostone in patients with chronic constipation.

AIMS: The aim of this study is to assess the efficacy and safety of lubiprostone in adults with chronic constipation. METHODS: This multicenter, parallel-group trial enrolled 237 patients with chronic constipation and randomized them to 4 weeks of double-blind treatment with oral lubiprostone 24 mcg or placebo twice daily. The primary efficacy endpoint was the number of spontaneous bowel movements (SBMs) after 1 week of treatment. Secondary evaluations included SBMs at weeks 2, 3, and 4; percentage of patients with a SBM within 24 h of first study dose; stool consistency; degree of straining; constipation severity; abdominal bloating and discomfort; global treatment effectiveness; and safety assessments. RESULTS: Lubiprostone-treated patients experienced greater mean numbers of SBMs at week 1 compared with placebo (5.89 versus 3.99, P = 0.0001), with significantly greater percentages having SBMs within 24 h of the first dose (61.3% versus 31.4%, P < 0.0001). At each assessment, SBM frequency and percentages of full responders (> or =4 SBM per week) were significantly greater among lubiprostone-treated patients compared with placebo (P < or = 0.0171). Lubiprostone-treated patients reported significant improvements in stool consistency, straining, and constipation severity at all weeks, and in abdominal bloating at week 1. Patient assessments of treatment effectiveness were significantly greater with lubiprostone compared with placebo at all weeks (P < 0.0004). Gastrointestinal-related disorders were the most common adverse events in both treatment groups. CONCLUSIONS: In patients with chronic constipation, lubiprostone produced a bowel movement in the majority of individuals within 24 h of initial dosing, with sustained improvement in frequency as well as other constipation symptoms over 4 weeks of treatment.

Multicenter, 4-week, double-blind, randomized, placebo-controlled trial of lubiprostone, a locally-acting type-2 chloride channel activator, in patients with chronic constipation.

OBJECTIVES: To assess the efficacy and safety of lubiprostone in adults with chronic constipation. METHODS: This multicenter, parallel-group, double-blind controlled trial enrolled 242 patients with constipation and randomized them to receive oral lubiprostone 24 mcg or placebo twice daily for 4 wk. The primary efficacy end point was the number of spontaneous bowel movements (SBMs; those occurring without use of constipation relieving medications) after 1 wk of double-blind treatment. Other evaluations included SBMs at weeks 2, 3, and 4; bowel movement (BM) characteristics (i.e., consistency and straining); constipation severity; abdominal bloating/discomfort; global treatment effectiveness ratings; and safety assessments. RESULTS: The 120 lubiprostone-treated patients reported a greater mean number of SBMs at week 1 compared with the 122 placebo-treated patients (5.69 vs 3.46, P= 0.0001), with a greater frequency of SBMs also reported at weeks 2, 3, and 4 (P

Review of the treatment options for chronic constipation.

Constipation is a common gastrointestinal motility disorder that is often chronic, negatively affects patients' daily lives, and is associated with high healthcare costs. There is a considerable range of treatment modalities available for patients with constipation; however, the clinical evidence supporting their use varies widely. Nonpharmacologic modalities, such as increased exercise or fluid intake and bowel habit training, are generally recommended as first-line approaches, but data on the effectiveness of these measures are limited. The clinical benefits of various traditional pharmacologic agents (many of which are available over the counter, such as laxatives and fiber supplements) remain unclear. Although these modalities may benefit some patients with temporary constipation, their efficacy in patients for whom constipation is chronic is less well defined. Some studies suggest benefit with psyllium, polyethylene glycol, and lactulose; however, the use of other agents, such as calcium polycarbophil, methylcellulose, bran, magnesium hydroxide, and stimulant laxatives, is not supported by strong clinical evidence. More recently, newer agents have been approved for the treatment of patients with chronic constipation on the basis of comprehensive clinical investigation programs. Tegaserod, with its well-established clinical profile, and lubiprostone, the latest addition to the treatment armamentarium, represent the new generation of therapies for chronic constipation. This article reviews the efficacy and safety of traditional therapies used in the management of the multiple symptoms associated with chronic constipation and discusses recently approved and emerging therapies for this disorder.

A randomized, multicenter study comparing the safety and efficacy of sodium phosphate tablets with 2L polyethylene glycol solution plus bisacodyl tablets for colon cleansing.

OBJECTIVE: The safety and efficacy of NaP tablets have not been compared with 2L PEG lavage solution. A multicenter, investigator-blinded study was conducted to compare the colon-cleansing efficacy of a new NaP tablet formulation with that of 2L PEG solution plus bisacodyl tablets in adults undergoing colonoscopy. METHODS: A total of 481 patients were randomized to receive either 32 tablets (48 g) of NaP or 2L PEG solution plus 4 (20 mg) bisacodyl tablets. Quality of colon cleansing was assessed using a 4-point scale (1 = excellent, 2 = good, 3 = fair, and 4 = inadequate), and the primary efficacy end point was mean overall colon-cleansing score. Safety assessments included recording of adverse events and changes in biochemical tests and vital signs. RESULTS: A total of 411 patients were included in the efficacy analysis. The mean overall and ascending colon-cleansing scores for NaP tablets were significantly better than PEG plus bisacodyl (overall 1.5 vs 1.8, ascending 1.4 vs 1.8, P < 0.0001 for both). Patients treated with NaP tablets experienced significantly fewer adverse events (66%vs 82%, P= 0.0003) and gastrointestinal symptoms (64%vs 79%, P= 0.0001) compared with patients receiving PEG plus bisacodyl. Patients receiving NaP tablets were significantly less likely to experience abdominal distention, abdominal pain, and vomiting than patients receiving PEG plus bisacodyl (P < 0.0012). Transient fluctuations in laboratory parameters were observed in both treatment groups; however, the fluctuations were more common and of greater magnitude in the NaP group particularly in phosphorous, sodium, and potassium. CONCLUSION: The colon-cleansing efficacy of the new 32-tablet NaP dosing regimen in this study was found to be significantly better than the 2L PEG solution plus bisacodyl tablets regimen. The 32-tablet NaP dosing regimen was associated with fewer adverse events. As expected electrolyte shifts were more common and of greater magnitude in the NaP group compared with the PEG plus bisacodyl group; however, both treatment groups demonstrated significant changes in electrolytes and creatinine.

Efficacy of tegaserod in chronic constipation in men.

OBJECTIVES: Chronic constipation/idiopathic constipation is highly prevalent in western countries and traditional treatments are suboptimal. This multicenter study evaluated the efficacy and safety of tegaserod, a selective 5-HT(4) agonist and promotility agent, in men with chronic constipation. METHODS: After screening and baseline phases, men with chronic constipation were randomized to receive either tegaserod 6 mg twice daily or placebo in a double-blind manner for 12 wk. Patients recorded symptoms using a diary. Primary efficacy variable was the response rate for an increase in complete spontaneous bowel movements (CSBMs) during the first 4 wk of double-blind treatment. Other efficacy measures included patient assessment of symptoms and satisfaction with symptom relief. Safety and tolerability were also evaluated. RESULTS: In total, 322 patients were randomized to tegaserod (N = 158) or placebo (N = 164). Increases of at least one CSBM per wk during the first 4 wk of treatment observed for tegaserod compared with placebo (40.5%vs 29.3%, P= 0.03) were sustained throughout the 12-wk treatment period. Response rate for CSBM was also superior for tegaserod (P= 0.04 vs placebo) over the treatment period. Benefits for tegaserod over placebo were also observed for some secondary efficacy variables, however, statistical significance was not achieved at all weeks. Frequency of adverse events was similar with tegaserod and placebo. CONCLUSIONS: Tegaserod 6 mg twice daily was effective and well tolerated in the treatment of chronic constipation in men. Tegaserod provided rapid relief of constipation within 1 wk and the effects were sustained for up to 12 wk.

Colonoscopic withdrawal times and adenoma detection during screening colonoscopy.

BACKGROUND: Colonoscopy is commonly used to screen for neoplasia. To assess the performance of screening colonoscopy in everyday practice, we conducted a study of the rates of detection of adenomas and the amount of time taken to withdraw the colonoscope among endoscopists in a large community-based practice. METHODS: During a 15-month period, 12 experienced gastroenterologists performed 7882 colonoscopies, of which 2053 were screening examinations in subjects who had not previously undergone colonoscopy. We recorded the numbers, sizes, and histologic features of the neoplastic lesions detected during screening, as well as the duration of insertion and of withdrawal of the colonoscope during the procedure. We compared rates of detection of neoplastic lesions among gastroenterologists who had mean colonoscopic withdrawal times of less than 6 minutes with the rates of those who had mean withdrawal times of 6 minutes or more. According to experts, 6 minutes is the minimum length of time to allow adequate inspection during instrument withdrawal. RESULTS: Neoplastic lesions (mostly adenomatous polyps) were detected in 23.5% of screened subjects. There were large differences among gastroenterologists in the rates of detection of adenomas (range of the mean number of lesions per subject screened, 0.10 to 1.05; range of the percentage of subjects with adenomas, 9.4 to 32.7%) and in their times of withdrawal of the colonoscope from the cecum to the anus (range, 3.1 to 16.8 minutes for procedures during which no polyps were removed). As compared with colonoscopists with mean withdrawal times of less than 6 minutes, those with mean withdrawal times of 6 minutes or more had higher rates of detection of any neoplasia (28.3% vs. 11.8%, P<0.001) and of advanced neoplasia (6.4% vs. 2.6%, P=0.005). CONCLUSIONS: In this large community-based gastroenterology practice, we observed greater rates of detection of adenomas among endoscopists who had longer mean times for withdrawal of the colonoscope. The effect of variation in withdrawal times on lesion detection and the prevention of colorectal cancer in the context of widespread colonoscopic screening is not known. Ours was a preliminary study, so the generalizability and implications for clinical practice need to be determined by future studies.

Maintenance of healed erosive esophagitis: a randomized six-month comparison of esomeprazole twenty milligrams with lansoprazole fifteen milligrams.

BACKGROUND AND AIMS: The aim was to compare esomeprazole with lansoprazole for the maintenance of healed erosive esophagitis and resolution of gastroesophageal reflux disease-related symptoms in a United States population. METHODS: Patients who entered this double-blind, randomized, parallel-group, multicenter, maintenance trial had been treated and healed (no endoscopic evidence of erosive esophagitis) with esomeprazole 40 mg or lansoprazole 30 mg once daily (patients with Los Angeles grades C and D erosive esophagitis at baseline) or esomeprazole 40 mg (patients with Los Angeles grades A and B erosive esophagitis at baseline) and had no heartburn or acid regurgitation symptoms during the previous week. Patients were randomized to maintenance once-daily therapy with esomeprazole 20 mg (n = 512) or lansoprazole 15 mg (n = 514) for up to 6 months. Esophago-gastroduodenoscopies were done at months 3 and 6, and investigators assessed symptom severity at months 1, 3, and 6. Endoscopic/symptomatic remission was defined as no erosive esophagitis and no study withdrawal as a result of reflux symptoms. RESULTS: The estimated endoscopic/symptomatic remission rate during a period of 6 months was significantly higher (P = .0007) for patients who received esomeprazole 20 mg once daily (84.8%) compared with those who received lansoprazole 15 mg (75.9%). Most patients had no heartburn (383/462 and 369/466) or acid regurgitation (401/462 and 400/466) symptoms at 6 months, and there were no significant differences between treatments. Both treatments were well-tolerated. CONCLUSION: Esomeprazole 20 mg is more effective than lansoprazole 15 mg in maintaining endoscopic/symptomatic remission in patients with healed erosive esophagitis.

Fiber for the treatment of hemorrhoids complications: a systematic review and meta-analysis.

OBJECTIVES: To evaluate the impact of laxatives on a wide range of symptoms in patients with symptomatic hemorrhoids. METHODS: We searched using the following sources: MEDLINE, EMBASE, CINAHL and CENTRAL, BIOSIS, AMED, Papers First and Proceedings; study authors, industry, and experts in the field. We included all published and unpublished parallel group randomized controlled trials comparing any type of laxative to placebo or no therapy in patients with symptomatic hemorrhoids. Two reviewers independently screened studies for inclusion, retrieved all potentially relevant studies, and extracted data on study population, intervention, prespecified outcomes, and methodology. RESULTS: Seven trials randomized 378 patients to fiber or a nonfiber control. Studies were of moderate quality for most outcomes. Meta-analyses using random effects models suggested that fiber has an apparent beneficial effect. The risk of not improving/persisting symptoms decreased by 47% in the fiber group (RR = 0.53, 95% CI 0.38-0.73) and the risk of bleeding by 50% (RR = 0.50, 95% CI 0.28-0.89). Studies with multiple follow-ups, usually at 6 wk and at 3 months, showed consistent results over time. Results are also compatible with large treatment effects in prolapse, pain, and itching, but even in the pooled analyses confidence intervals were wide and compatible with no effect (RR = 0.79, 95% CI 0.37-1.67; RR = 0.33, 95% CI 0.07-1.65; and RR = 0.71, 95% CI 0.24-2.10, respectively). One study suggested a decrease in recurrence. Results showed a nonsignificant trend toward increases in mild adverse events in the fiber group (RR = 6.0, 95% CI 0.57-64.8). CONCLUSIONS: Trials of fiber show a consistent beneficial effect for symptoms and bleeding in the treatment of symptomatic hemorrhoids.

Healing of gastric ulcers with esomeprazole versus ranitidine in patients who continued to receive NSAID therapy: a randomized trial.

OBJECTIVE: To compare orally administered esomeprazole 40 mg once daily and 20 mg once daily with ranitidine 150 mg twice daily for the healing of gastric ulcers (GUs) during 8 wks in patients who continued to receive daily nonsteroidal anti-inflammatory drug (NSAID) therapy. METHODS: This multicenter, randomized, double-blind, parallel-group trial included patients who were receiving nonselective or cyclo-oxygenase-2 (COX-2)-selective NSAIDs and had at least one GU >or=5 mm but no gastric or duodenal ulcer >25 mm in diameter at the baseline esophagogastroduodenoscopy (EGD). After 4 and 8 wks of treatment, ulcer-healing status was confirmed by EGD. The primary outcome was the percentage of patients in each treatment group who had no GUs (GU healing rate) at week 8. RESULTS: A total of 406 patients were randomized to treatment. At week 8, GU healing rates with esomeprazole 40 and 20 mg were 91.5% (118/129; 95% CI, 86.7-96.3%) and 88.4% (122/138; 95% CI, 83.1-93.7%), respectively, and were significantly higher than the 74.2% rate (98/132; 95% CI, 66.8-81.7%) with ranitidine (p<0.01 for both comparisons). GU healing rates at 4 wks (78.3%[101/129] and 79.0%[109/138] in the esomeprazole 40- and 20-mg groups, respectively) were also significantly higher (p<0.05) than in the ranitidine group (66.7%[88/132]). All treatments were well tolerated. CONCLUSIONS: Esomeprazole 40 and 20 mg once daily are effective and well-tolerated therapies compared with ranitidine 150 mg twice daily for healing GUs in patients who need to continue NSAID therapy.

Effect of tegaserod in chronic constipation: a randomized, double-blind, controlled trial.

BACKGROUND AND AIMS: Chronic constipation is a common gastrointestinal disorder. The aim of this study was to evaluate the efficacy, safety, and tolerability of tegaserod, a serotonin subtype 4 receptor partial agonist in patients with chronic constipation. METHODS: This was a randomized, double-blind, placebo-controlled study. After a 2-week baseline, patients received tegaserod 2 mg twice daily (n = 450), tegaserod 6 mg twice daily (n = 451), or placebo (n = 447) for 12 weeks, followed by a 4-week withdrawal period. Responders were those patients having been treated for at least 7 days with an increase of > or =1 complete spontaneous bowel movement/week vs. baseline during weeks 1-4 (primary variable) and weeks 1-12 (secondary variable). Other secondary variables included patient assessment of constipation symptoms (number of bowel movements, stool form, abdominal bloating/distention, straining, and abdominal pain/discomfort), and global assessment of constipation and bowel habits. RESULTS: Responder rates for complete spontaneous bowel movement during weeks 1-4 were significantly greater ( P < 0.0001) in the tegaserod 2 mg twice daily (41.4%) and 6 mg twice daily groups (43.2%) vs. placebo (25.1%). This effect was maintained over 12 weeks. Statistically significant improvements over placebo were observed across the majority of secondary variables for both tegaserod doses. No rebound effect was observed after treatment withdrawal. Tegaserod was well tolerated; headache and nasopharyngitis, the most frequent adverse events, were more common in the placebo group than in either tegaserod group. CONCLUSIONS: Over 12 weeks, tegaserod treatment produced significant improvements in chronic constipation symptoms and was also safe and well tolerated.

Epidemiology of constipation in North America: a systematic review.

OBJECTIVE: The aim of this study was to systematically review the published literature regarding prevalence, risk factors, incidence, natural history, and the effect on quality of life of constipation in North America. METHODS: A computer-assisted search of MEDLINE, EMBASE, and Current Contents databases was performed independently by two investigators. Study selection criteria included the following: (1) North American population-based sample of adults with constipation; (2) publication in full manuscript form in English; and (3) report on the prevalence, incidence, and natural history of constipation or impact of constipation on quality of life. Eligible articles were reviewed in a duplicate, independent manner. Data extracted were compiled in tables and presented in descriptive form. RESULTS: The estimates of the prevalence of constipation in North America ranged from 1.9% to 27.2%, with most estimates from 12% to 19%. Prevalence estimates by gender support a female-to-male ratio of 2.2:1. Constipation appears to increase with increasing age, particularly after age 65. No true population-based incidence studies or natural history studies were identified. In one cohort, 89% of patients with constipation still reported constipation at 14.7 months follow-up. From limited data, quality of life appears to be diminished by constipation, but the clinical significance of this is unclear. CONCLUSIONS: Constipation is very common, as approximately 63 million people in North America meet the Rome II criteria for constipation. Minimal data are available regarding incidence, natural history, and quality of life in patients with constipation. Effort should be expended toward the study of these topics, particularly in the elderly, who are disproportionately affected by this condition.

Obscure gastrointestinal bleeding.

This is one of a series of statements discussing the utilization of GI endoscopy in common clinical situations. The Standards of Practice Committee of the American Society for Gastrointestinal Endoscopy prepared this text. In preparing this guideline, a MEDLINE literature search was performed, and additional references were obtained from the bibliographies of the identified articles and from recommendations of expert consultants. When little or no data exist from well-designed prospective trials, emphasis is given to results from large series and reports from recognized experts. Guidelines for appropriate utilization of endoscopy are based on a critical review of the available data and expert consensus. Further controlled clinical studies are needed to clarify aspects of this statement, and revision may be necessary as new data appear. Clinical consideration may justify a course of action at variance to these recommendations.