Constipation, laxative use and risk of colorectal cancer: The Miyagi Cohort Study

Review article: do stimulant laxatives damage the gut? A critical analysis of current knowledge

Stimulant laxatives are well established as first- or second-line treatments for constipation and although they have a reliable therapeutic effect, alleged safety concerns still exist, particularly with long-term use. The potential harmful effects on the gastrointestinal system (including carcinogenicity) of the long-term use of diphenylmethane [bisacodyl, sodium picosulfate (SPS)] and senna stimulant laxatives were assessed in a comprehensive review of the publications identified in literature searches performed in PubMed and Embase up to and including June 2023. We identified and reviewed 43 publications of interest. While stimulant laxatives at supratherapeutic doses have been shown to cause structural alterations to surface absorptive cells in animals and humans, these effects are reversible and not considered clinically relevant. No formal long-term studies have demonstrated morphological changes in enteric neural elements or intestinal smooth muscle with bisacodyl or SPS in humans. Furthermore, there is no convincing evidence that stimulant laxatives are associated with the development of colon cancer, and in fact, chronic constipation itself has been reported to potentially increase the risk of colon cancer, therefore, the use of stimulant laxatives might reduce this risk. Many studies suggesting a possible harmful effect from laxatives were limited by their failure to consider confounding factors such as concomitant neurological disease, metabolic disorders, and age. These findings highlight the lack of evidence for the harmful effects of laxatives on the colon, and thus, the benefits of treatment with stimulant laxatives, even in the long-term, should be reconsidered for the management of patients with constipation.

Trends in colorectal cancer screening compliance and incidence among 60- to 74-year-olds in China

BACKGROUND

Compliance with colonoscopy among elderly individuals participating in colorectal cancer (CRC) screening programs is unsatisfactory, despite a high detection rate of bowel-related diseases. In this study, our aim was to analyze the impact of risk factors on the trends of compliance and detection rates in colonoscopy among high-risk individuals aged 60-74.

METHODS

A retrospective study was conducted on the high-risk individuals aged 60-74 participating in the 2021 CRC screening program in Tianjin, China. Logistic regression analyses, including both univariate and multivariate analyses, were performed to explore the impact of different risk factors on colonoscopy compliance among the high-risk individuals. Besides, the study investigated the influence of various risk factors on the detection rates of bowel-related diseases among the high-risk individuals who underwent colonoscopy.

RESULTS

A total of 24,064 high-risk individuals were included, and 5478 individuals received a free colonoscopy, with an overall compliance of 22.76%. Among them, the adenoma detection rate was 55.46%. Males and individuals with a positive FIT had high compliance and detection rates for CRC, advanced adenomas (AA), advanced colorectal neoplasia (ACN), and colorectal neoplasm (CN). Individuals aged 70-74 were associated with low compliance but high CRC, ACN, and CN detection rates. Individuals who reported a history of chronic constipation, bloody mucous, and CRC in first-degree relative showed high compliance but no significantwere associated with the detection rates of CRC, AA, and CN.

CONCLUSION

This study reported several risk factors associated with the screening behaviors for CRC. Patterns and trends in CRC, AA, ACN, and CN compliance and detection rates correlate with risk factors.

Current Management of Chronic Constipation in Japan

Constipation is a complicated condition. Chronic constipation is diagnosed when constipation occurs for more than 3 months. Chronic constipation is classified using patient symptoms and the pathophysiology. New therapeutic agents to treat chronic constipation have recently been approved in Japan. However, treatments for constipation that is refractory to traditional laxatives have been approved, an algorithm for the treatment of chronic constipation has not yet been developed. The accumulation of knowledge and data is necessary to develop a new algorithm.

Intestinal flora in the constipation patients before versus after lactulose intervention

This study aimed to investigate the characteristics of intestinal flora in patients with chronic functional constipation before and after lactulose intervention. Twenty-nine patients with constipation in the treatment group received oral lactulose (15 mL/d) for a month. Twenty healthy subjects served as controls. Stool specimens were collected before and after lactulose treatment. Fecal bacteria were examined by 16SrRNA gene sequencing and bioinformatics analysis. After lactulose treatment, most bacteria in the constipation group, including Bifidobacteria, Bacillus cereus, Prevotella, Bacillus, Anaerostipes, Oribacterium, and Mogibacterium increased as compared to those in the healthy control group. Anaerotruncus declined in the healthy control group after lactulose treatment. Our study shows lactulose can increase the abundance of probiotics, optimize the intestinal microenvironment, and alleviate constipation.

Chronic Constipation as a Risk Factor for Colorectal Cancer: Results From a Nationwide, Case-Control Study

BACKGROUND & AIMS

Prolonged colon transit times may increase the contact time between potential carcinogens in the stool and the colonic mucosa. Nonetheless, previous studies have yielded conflicting results connecting chronic constipation with the risk of colorectal cancer (CRC). We examined the association between chronic constipation and later CRC.

METHODS

In this nationwide case-control study, we identified 41,299 CRC cases by colorectal biopsy in Sweden between July 2007 and December 2016 and matched them to 203,181 age- and sex-matched controls from the general population. We compared odds of earlier chronic constipation (defined as ≥2 laxative prescriptions in the Prescribed Drug Register with ≥6 months between the first and last prescription) between CRC cases and controls using logistic regression. In separate analyses, we compared odds of earlier constipation between CRC cases and sibling comparators, but also examined earlier risk of having an inpatient/outpatient specialty diagnosis of chronic constipation before CRC.

RESULTS

Overall, 3943 patients with CRC met our criteria for chronic constipation before CRC. The crude proportion of chronic constipation in CRC patients was 9.5% compared with 8.8% in controls. After multivariable adjustment, there was a modest association between chronic constipation and later CRC (odds ratio [OR], 1.10; 95% CI, 1.06-1.14) that vanished using sibling comparators to control for residual confounding (OR, 1.04; 95% CI, 0.97-1.13). In a sensitivity analysis of 126,650 CRC patients diagnosed from 1989 to 2016, we found no association with earlier chronic constipation diagnosed in inpatient/outpatient specialty clinics (OR, 0.88; 95% CI, 0.75-1.04).

CONCLUSIONS

In a nationwide case-control study, chronic constipation was not associated with later CRC.

Biofeedback therapy combined with Baduanjin on quality of life and gastrointestinal hormone level in patients with colorectal cancer

BACKGROUND

With the change in people’s lifestyles, the incidence of colorectal cancer (CRC) is increasing. It is essential to study the efficacy of various treatment methods for CRC patients to prevent and treat CRC.

AIM

To investigate the efficacy of biofeedback therapy combined with Baduanjin in improving the quality of life and gastrointestinal hormone levels of patients with CRC.

METHODS

A total of 120 patients with CRC who were admitted to our hospital from June 2020 to June 2021 were included in the study. They were randomly divided into four groups (n = 30): the control group (group A), the biofeedback therapy intervention group (group B), the Baduanjin exercise intervention group (group C), and the combination group (group D). Patients in group A adopted the standard nursing mode and necessary health education. Patients in group B were treated with biofeedback therapy based on routine nursing care. Patients in group C were given Baduanjin intervention for 12 wk based on conventional drug treatment and care. Patients in group D were treated with biofeedback therapy and Baduanjin exercise. In this study, patients’ quality of life, gastrointestinal hormone levels, and clinical efficacy in the four groups were observed at baseline and 12 wk after intervention. Meanwhile, the correlation between gastrointestinal hormone levels and various functional areas of quality of life was analyzed. By comparing the observed indicators of patients in the four groups, the efficacy of biofeedback therapy combined with Baduanjin in improving the quality of life and gastrointestinal hormone levels of patients with CRC was explored.

RESULTS

At baseline, there were no significant differences in quality of life, gastrointestinal hormone levels, or clinical efficacy among the four groups (P > 0.05). Twelve weeks after the intervention, the combination group’s quality of life, gastrointestinal hormone levels, and clinical effectiveness were better than those of the three other groups.

CONCLUSION

On the basis of routine nursing care, patients with CRC combined with biofeedback therapy and Baduanjin exercise can improve the quality of life of patients with CRC and the efficacy of gastrointestinal hormone levels.

Constipation Is a Frequent Problem Associated with Vascular Complications in Patients with Type 2 Diabetes: A Cross-sectional Study

Objective Diabetes is recognized as an underlying disease of constipation. However, the prevalence of constipation varies according to the diagnostic criteria applied. We investigated the prevalence of constipation based on the new guideline for constipation in Japanese patients with type 2 diabetes and examined the relationship with the clinical background, including diabetic vascular complications. Methods Questionnaire surveys including items concerning the diagnosis and treatment status of constipation were administered to 410 patients with type 2 diabetes. Results Although 29% of the patients considered that they had experienced constipation (self-judged), only 14% had consulted a physician about constipation. The prevalence of chronic constipation based on the guideline was 26%. After including laxative users, constipation was finally found in 36%. Despite the use of laxatives (n=81), 51% of the patients were still diagnosed with chronic constipation. Patients with constipation (chronic constipation or laxative use) were significantly older and had a longer duration of diabetes than those without constipation. The body mass index (BMI) of patients with constipation (24.9±3.8 kg/m²) was significantly lower than that of those without constipation (26.3±4.6 kg/m²). Diabetic neuropathy (49% vs. 32%) and coronary heart disease (CHD) (27% vs. 13%) were significantly more frequent in the patients with constipation than in those without constipation. A multivariate logistic regression analysis revealed that gender, BMI, diabetic neuropathy, insulin use, and CHD were significantly associated with constipation. Conclusion An accurate diagnosis of constipation is desirable in patients with type 2 diabetes because constipation is independently associated with CHD.

Laxative use and mortality in patients on haemodialysis: a prospective cohort study

BACKGROUND

Patients on haemodialysis (HD) are often constipated. This study aimed to assess the relationship between constipation and mortality in such patients. In this study, constipation was defined as receiving prescription laxatives, based on the investigation results of "a need to take laxatives is the most common conception of constipation" reported by the World Gastroenterology Organization Global Guidelines.

METHODS

This cohort study included 12,217 adult patients on HD enrolled in the Japan-Dialysis Outcomes and Practice Patterns study phases 1 to 5 (1998 to 2015). The participants were grouped into two based on whether they were prescribed laxatives during enrolment at baseline. The primary endpoint was all-cause mortality in 3 years, and the secondary endpoint was cause-specific death. Missing values were imputed using multiple imputation methods. All estimations were calculated using a Cox proportional hazards model with an inverse probability of treatment weighting using the propensity score.

RESULTS

Laxatives were prescribed in 30.5% of the patients, and there were 1240 all-cause deaths. There was a significant association between laxative prescription and all-cause mortality [adjusted hazard ratio (AHR), 1.12; 95% confidence interval (CI): 1.03 to 1.21]. Because the Kaplan-Meier curves of the two groups crossed over, we examined 8345 patients observed for more than 1.5 years. Laxative prescription was significantly associated with all-cause mortality (AHR, 1.35; 95% CI: 1.17 to 1.55). The AHR of infectious death was 1.62 (95% CI: 1.14 to 2.29), and that of cancerous death was 1.60 (95% CI: 1.08 to 2.36). However, cardiovascular death did not show a significant inter-group difference.

CONCLUSIONS

Constipation requiring use of laxatives was associated with an increased risk of death in patients on HD. It is important to prevent patients receiving HD from developing constipation and to reduce the number of patients requiring laxatives.

Association of bowel movement frequency and laxative use with risk of hepatocellular carcinoma in US women and men

Abnormal bowel movements have been related to a variety of hepatocellular carcinoma (HCC) risk factors such as dyslipidemia, diabetes and altered metabolism of bile acids and gut microbiota. However, little is known about whether bowel movement frequency affects the risk of developing HCC. We followed 88 123 women in the Nurses' Health Study (NHS) and 28 824 men in the Health Professionals Follow-up Study (HPFS) for up to 24 years. The Cox proportional hazards regression model was used to calculate multivariable hazard ratios (HRs) and confidence intervals (95%CI). We documented 101 incident HCC cases. Compared to those with daily bowel movements, participants with bowel movement more than once per day had a multivariable HR of 1.93 (95%CI: 1.18 to 3.16) in the pooled cohorts. For the same comparison, the positive association appeared stronger for men (2.72, 95% CI: 1.14 to 6.44) than for women (1.63, 95% CI: 0.87 to 3.06) but there was no statistically significant heterogeneity by sex (P-value = .31). We found null associations between bowel movement every 2 days or less and the risk of HCC (HR = 1.05, 95%CI: 0.62 to 1.79). The HR (95%CI) for participants who used laxatives regularly relative to those who never used laxatives was 1.00 (0.64 to 1.55). Our results suggest participants with bowel movement more than once daily is associated with a higher risk of developing HCC compared to those with daily bowel movements. These findings need to be confirmed and potential mechanisms underlying this association need to be elucidated.

Aloe-emodin, a hydroxyanthracene derivative, is not genotoxic in an in vivo comet test

Aloe-emodin, one of the molecules belonging to the group of hydroxyanthracene derivatives, was recently described as genotoxic in vivo. Indeed, the EFSA judged that aloe-emodin, together with other similar molecules (emodin and danthron) and extracts from the leaf of Aloe species containing hydroxyanthracene derivatives, could represent a risk factor for colorectal cancer mediated by a genotoxic effect. Given the marked uncertainty regarding the conclusions in the opinion of the EFSA ANS Panel and conflicts in the epidemiological data on which the opinion is based, a new in vivo study (in vivo alkaline comet assay in mice - OECD 489) was conducted to test the potential genotoxicity of aloe-emodin at doses of 250, 500, 1000 and 2000 mg/kg bw/day on preparations of single cells from the kidney and colon of treated male mice. Following treatment with the test item, no clinical signs were observed in animals in any treatment group. Slight body-weight loss was randomly observed in all groups treated with the test item and was more evident in the groups dosed at 1000 and 2000 mg/kg bw/day. Under these experimental conditions, aloe-emodin showed no genotoxic activity. Possible oxidative damage to colon tissues could not be excluded based on the results obtained after repair enzyme treatment.

Risk factors of colorectal cancer among Saudi Population: Case-control study

Background:

Colorectal cancer (CRC) incidence and related mortalities have been steadily increasing in KSA over the past 20 years. CRC in the Kingdom of Saudi Arabia (KSA) population presents in younger ages and in more advanced disease states as compared to other countries. This study was aimed to determine factors (demographic, habitual, environmental, nutritional, and genetic) associated with CRC in Riyadh, KSA.

Materials and Methods:

A matched case-control study conducted in the major hospitals in Riyadh (King Khalid university Hospital, King Faisal Specialist Hospital, Riyadh Military Hospital, Security Force Hospital, King Fahd Medical City). Here most of CRC cases are managed. The cases (n = 121) group included all recently diagnosed and pathologically confirmed Saudi cases of CRC identified during the period 1^st of January 2017 till 31^st of December 2018 who agreed to participate and fulfilled the inclusion criteria. A similar number of controls attending the study settings were selected consecutively from the clinics where cases were managed and matched on a 1:1 basis with cases based on age (+/-3 years) and gender. Data were collected using a structured questionnaire. Conditional logistic regression models were fitted to determine factors associated with risk of CRC.

Result:

This study included similar number of males and females in both groups: males 69 (57%) and females 52 (43%) in each group (Chi-square test P = 1.0). The mean (S.D) age in the cases group was 53.6 (S.D = 12.9) and 53.3 (S.D = 12.9) in the controls group (Student test P = 0.86). In the final multivariate conditional logistic regression model, variables independently associated with risk of colorectal cancer were body mass index (OR = 0.93; 95% CI 0.87–0.98; P = 0.011) employment status (inverse relation: OR = 0.33; 95% CI 0.14–0.77; P = 0.010), colon polyps (OR = 4.09; 95% CI 1.06–15.82; P = 0.041), and constipation (OR = 4.98; 95% CI 1.91–15.99; P = 0.001).

Conclusion:

Factors associated with CRC in the major referral hospitals in KSA were colon polyps, chronic constipation, and unemployment. These factors should be considered when screening for patients at risk for CRC.

Investigation of the Association between Drinking Water Habits and the Occurrence of Women Breast Cancer

Risk and protective factors for breast cancer (BC) include lifestyle, diet, reproduction, and others. Increased risk for colon cancer was linked with low water intake. The link between water consumption and BC was scarcely studied. We investigated the association between water and fluid consumption and the occurrence of BC in a retrospective case-control study in the Shaare Zedek Medical Center, Jerusalem, in 206 women aged 25-65 years (106 with newly diagnosed BC, and 100 controls). A food frequency questionnaire (FFQ), consumption of water, foods, and beverages, lifestyle, and other risk and protective factors were recorded. The age of women in both groups was comparable ((M ± SD) 52.7 ± 9.8 and 50.6 ± 11.4 years, respectively (p = 0.29)). Women with BC consumed 20.2% less water (M ± SD = 5.28 ± 4.2 and 6.62 ± 4.5 cups/day, respectively, p = 0.02) and 14% less total fluids than controls (M ± SD = 2095 ± 937 mL/day and 2431 ± 1087 mL/day, respectively, p = 0.018). Multiple stepwise logistic regression showed that the differences remained significant both for daily water consumption (p = 0.031, CI = 0.462-0.964) and for total daily liquid intake (p = 0.029, CI = 0.938-0.997). Low water and liquids intake as a risk factor for BC may be related to the younger age of our subjects. The effect of age on the potential role of water intake in decreasing BC risk should be investigated.

Polyethylene glycol 3350 plus electrolytes for pediatric chronic constipation: An open-label clinical study in Japan

BACKGROUND

Despite the abundance of study evidence for its efficacy and tolerability for the treatment of constipation in other countries, polyethylene glycol 3350 plus electrolytes (PEG3350+E) was not available in Japan until recently. The purpose of this study was to establish the efficacy and safety of PEG3350+E for the treatment of functional constipation in children in Japan.

METHODS

Japanese children aged 2-14 years with a mean spontaneous bowel movement (SBM) frequency of 2 times/week or less for at least 2 months prior to informed consent were enrolled into the study. After a 2-week screening period, treatment with PEG3350+E was initiated on the day of enrollment and continued for 12 weeks. Change in SBM frequency from screening period week 2 (baseline) to treatment period week 2 was set as the primary endpoint. Secondary endpoints and adverse events were also examined.

RESULTS

Thirty-nine patients were enrolled and completed the 12-week study period. The SBM frequency (mean ± SD) at baseline and treatment period week 2 was 1.00 ± 0.89 and 6.54 ± 4.38, respectively. The change in SBM frequency was 5.54 ± 4.55 (one-sample t test, P < 0.0001) and remained stable through week 12. Stool consistency was also improved over the entire treatment period. Three mild adverse drug reactions were reported: decreased appetite, abdominal pain, and diarrhea (each in 1 of 39 [2.6%] patients).

CONCLUSION

PEG3350+E can be considered as a new treatment option for chronic constipation in children in Japan.

CLINICAL TRIAL REGISTRATION NUMBER

Japic CTI-163167.

Abnormal bowel movement frequency increases the risk of rectal cancer: evidence from cohort studies with one million people

Previous studies from case-control studies failed to draw reliable conclusions regarding the relationship between bowel movement frequency and the risk of colorectal cancer. To further examine this relationship, we collect the data from cohort studies that make a more accurate estimation. Several online data were searched from inception to February 29, 2020. Ten cohort studies involving 1,038,598 individuals were included in our study. The pooled results indicated that a bowel movement of less than once per day was not associated with the risk of colorectal cancer (relative risk (RR)= 1.00, 95% confidence interval (CI): 0.87-1.16, P = 0.950) compared with that of once per day. Compared with a bowel movement frequency of once per day, a bowel movement of more than once per day was also not related to elevated risk of colorectal cancer (RR = 1.04, 95% CI: 0.91-1.19, P = 0.570). The subgroup analyses indicated a low or high bowel movement frequency did not increase the risk of colon cancer (RR = 0.91, 95% CI: 0.80-1.03, P = 0.130). However, an increased frequency of bowel movements increased the risk of rectal cancer (RR = 1.34, 95% CI: 1.19-1.52, P < 0.001). The sensitivity analysis still supports the results. No significant publication bias existed. The data from cohort indicated that less bowel movement frequency was not associated with the risk of colorectal cancer. The frequency of bowel movement affects the risk of rectal cancer.

Constipation in chronic kidney disease: it is time to reconsider

Constipation is highly prevalent in patients with chronic kidney disease (CKD) and is primarily characterized by decreased intestinal motility. This chronic disorder affects the quality of life of patients. However, nephrologist and dialysis clinicians have long had a disproportionately limited understanding of constipation. Accumulating evidence has revealed a relationship between constipation and cardiovascular disease and CKD. The pathogenesis of constipation in CKD patients is multifactorial: decreased physical activity, comorbidities affecting bowel movement, such as diabetes mellitus, cerebrovascular disease, and hyperparathyroidism, a restricted dietary intake of plant-based fiber-rich foods, and multiple medications, including phosphate binders and potassium-binding resins, have all been implicated. CKD is associated with alterations in the composition and function of the gut microbiota, so-called gut dysbiosis. Recent studies showed that CKD-related gut dysbiosis decreased intestinal motility via intestinal inflammation or the increased generation of gut-derived uremic toxins, such as indoxyl sulfate and p-cresyl sulfate. Furthermore, the gastrointestinal secretion of mucin was found to be decreased in CKD animal models, which may delay colonic transit by diminished lubrication in the alimentary tract. Thus, CKD-related gut dysbiosis may play a role in constipation, but limited information is currently available. Since constipation is often intractable, particularly in CKD patients, every available means needs to be employed in its treatment. The effects of probiotics, prebiotics, and synbiotics on the composition of the gut microbiota and gut-derived uremic toxins have been increasingly reported. However, their effects on stool consistency or frequency in CKD patients remain unclear. Some laxatives may be beneficial for improving not only bowel habits but also gut dysbiosis. Further studies are required to elucidate the CKD-specific pathogenesis of constipation and develop novel effective treatment options.

Risk of cancer in patients with fecal incontinence

BACKGROUND

Fecal incontinence may be an early symptom of cancer, but its association with cancer remains unclear. We examined the risk of selected cancers, including colorectal cancer, other gastrointestinal cancers, hormone-related cancers, and lymphoma, in patients with fecal incontinence.

METHODS

Using Danish population-based registries, all patients with hospital-based diagnoses of fecal incontinence during 1995-2013 were identified. We calculated cumulative incidences of cancers. As a measure of relative risks, we computed standardized incidence ratios (SIRs), that is, the observed number of cancers relative to the expected number based on national incidence rates by sex, age, and calendar year.

RESULTS

Among 16 556 patients with fecal incontinence, the cumulative incidence of colorectal cancers, other gastrointestinal cancers, hormone-related cancers, and lymphoma each was less than 0.4% after 1 year. It increased to under 3% after 10 years. The SIR for any cancer during 19 years of follow-up was 1.12 [95% confidence interval (CI), 1.06-1.19]. The SIRs during the first year were 2.31 (95% CI, 1.65-3.13) for colorectal cancer, 1.56 (95% CI, 0.89-2.54) for other gastrointestinal cancers, 1.00 (95% CI, 0.72-1.35) for hormone-related cancers, and 2.02 (95% CI, 1.01-3.61) for lymphoma. Beyond 1 year, the SIR reached unity for other gastrointestinal cancers, hormone-related cancers, and lymphoma, while a reduced risk was observed for colorectal cancer (SIR = 0.77, 95% CI, 0.59-0.98).

CONCLUSIONS

Fecal incontinence was a marker of cancer, especially gastrointestinal cancers and lymphoma within 1 year, which presumably is driven partly by reverse causation. However, the absolute risks were low. Heightened diagnostic efforts may explain in part the increased short-term risk of colorectal cancers.

Risk of cancer in patients with constipation

Background: It remains unclear whether constipation is associated with cancer. We evaluated the risk of malignancies in patients with constipation requiring hospitalization. Methods: Using Danish medical registries, we calculated cumulative incidences and standardized incidence ratios (SIRs) for cancer. SIRs were computed as the observed number of gastrointestinal (GI) cancers and selected non-GI cancers in patients with constipation compared with the expected number based on national incidence rates by sex, age, and calendar year (1978-2013). Results: We identified 1,75,901 patients with constipation (59% females, median age 54 years). The cumulative incidences of GI cancers and non-GI cancers after 15 years of follow-up were 2.5% and 2.6%, respectively. During the first year of follow-up, the SIR for any GI cancer was 5.0 (95% confidence interval (CI): 4.8-5.3), driven by colon and pancreas cancers and higher for younger age groups. Beyond 1 year of follow-up, the risk declined to near unity for colorectal cancer. The risk of other GI cancers (including cancers of the esophagus, stomach, small intestine, liver, and pancreas) remained moderately increased (overall SIR =1.3, 95% CI: 1.2-1.4). Except for ovarian cancer (SIR =7.3, 95% CI: 6.3-8.4), the risk of non-GI cancers was only slightly increased during the first year of follow-up and declined to unity thereafter. Conclusions: Patients with constipation had increased short-term risk of a diagnosis of GI cancer. Beyond 1 year of follow-up, a moderately elevated risk persisted only for GI cancers other than colorectal cancer. The risk of non-GI cancers was elevated only during the first year of follow-up, particularly for ovarian cancer.

Laxative type in relation to colorectal cancer risk

PURPOSE

Existing studies on laxatives, used by roughly 40% of the U.S. population experiencing constipation and colorectal cancer (CRC) have yielded inconsistent results, which may be due to a failure to account for differential risks by major laxative types: bulk (fiber-based), and nonbulk (or nonfiber-based).

METHODS

We examined the association of nonfiber-based laxative use and fiber-based laxative use with the risk of CRC in a subset of the multisite, International Colon Cancer Family Registry cohort comprising 4930 primary invasive CRC cases and 4025 controls selected from the general population. Epidemiologic risk factor questionnaires were administered to all participants at recruitment, and exposures were ascertained approximately 1 year before diagnosis for cases and at a comparable period for controls. We ascertained known and suspected CRC risk factors, including regular laxative use, which was defined as laxative intake at least twice a week for more than a month. Multivariable logistic regression models were used to estimate the adjusted odds ratios (ORs) and 95% confidence intervals (95% CIs).

RESULTS

Individuals who reported using nonfiber-based laxatives regularly were at a significantly increased risk for CRC compared with those who reported no laxative use (OR = 2.17, 95% CI = 1.47-3.19). No statistically significant associations were observed between fiber-based laxative use and CRC (OR = 0.99, 95% CI = 0.80-1.22).

CONCLUSIONS

Compared with nonusers, the risk of CRC increased with nonfiber-based laxative use, whereas CRC risk was not significantly associated with fiber-based laxative use.

Comparative Epidemiological Investigation of Alzheimer's Disease and Colorectal Cancer: The Possible Role of Gastrointestinal Conditions in the Pathogenesis of AD

Alzheimer's disease (AD) is a neurodegenerative disorder that affects approximately 35 million people worldwide, and diet has been reported to influence the prevalence/incidence of AD. Colorectal cancer is among the most common cancers in Western populations, and the correlation between constipation and the occurrence of colorectal cancer has been identified in a number of studies, which show that a Westernized diet is a mutual risk factor. Constipation is a growing health problem, particularly in middle-aged and older adults. As the most common gastrointestinal disorder in adults, constipation affects 2-20% of the world population, and it is associated with several diseases, such as diabetes, Parkinson's disease, and others. Comparing the epidemiological data on colorectal cancer and AD, we find that colorectal cancer and AD have similar epidemiologic feature, which is both disease correlate with high prevalence of constipation. Therefore, we hypothesized that constipation may influence Alzheimer's disease in a similar way that it contributes to colorectal cancer. This review aimed to systemically elucidate the evidence that constipation contributes to Alzheimer's disease progression.

The Cost Effectiveness of Lubiprostone in Chronic Idiopathic Constipation

OBJECTIVE

The objective of this study was to evaluate the cost effectiveness of lubiprostone, prucalopride, placebo and immediate referral to secondary care in chronic idiopathic constipation (CIC) in an economic model that was used by the UK National Institute for Health and Care Excellence (NICE) in developing guidance.

METHODS

We developed a cohort state-transition model to reflect the treatment pathway in CIC from the UK NHS and personal social services perspective. Time on treatment was determined by a treatment continuation rule using data from an indirect comparison and survival curves fitted to long-term data. Quality of life was defined by whether CIC was resolved or unresolved, using published values. Costs were determined by drug acquisition costs, invasive procedures and healthcare resource use (associated with resolved or unresolved CIC), using published UK sources. Deterministic and probabilistic sensitivity analyses were conducted.

RESULTS

Over a 10-year time horizon, lubiprostone was more costly and more effective than placebo and immediate referral to secondary care, with incremental cost-effectiveness ratios (ICERs) of £58,979 and £21,152. Lubiprostone dominated prucalopride in the base case and with a time horizon of 1 year. The main sensitivity for the comparison against placebo was the assumptions around placebo cost and efficacy. The main sensitivity for the comparison against prucalopride was the endpoint used in the indirect comparison.

CONCLUSION

Lubiprostone may be cost effective compared with prucalopride or immediate referral but not compared with placebo in the base case. The implementation of the guidance issued by NICE should increase quality of life for patients with CIC and provide a further treatment option.

Effects of resistant maltodextrin on bowel movements: a systematic review and meta-analysis

It is well known that dietary fiber helps to relieve and prevent constipation, and there are a number of scientific papers, including systematic reviews and meta-analyses on the effects of naturally derived dietary fiber on bowel movements. In recent years, there has been an increase in the manufacture of dietary fiber ingredients obtained from food raw materials, and these are now commonly available in the market. Resistant maltodextrin (RMD), a soluble dietary fiber, is manufactured from starch, and industrially produced soluble dietary fiber is used worldwide. While there are many reports on the effects of RMD on bowel movements, no systematic review or meta-analysis has been reported. We conducted a systematic review and meta-analysis to clarify the effect of RMD on bowel movements based on stool frequency and stool volume. We also investigated the subjective evaluation of RMD effects on bowel movements. Of a total of 314 potentially relevant articles, 28 articles met the eligibility criteria, and 29 randomized controlled trials were identified. As a result of integration analyses, we found that the intake of RMD significantly increased stool volume and stool frequency compared with placebo intake. Furthermore, RMD intake tended to improve sensation of complete/incomplete evacuation. In conclusion, the evidence suggests that RMD has a positive effect on bowel movements, contributing to normal bowel function. This finding will help in the development of new criteria for choice of dietary fiber in the process of developing food products.

Laxative effect of repeated Daiokanzoto is attributable to decrease in aquaporin-3 expression in the colon

Daiokanzoto (DKT) exerts its laxative effect via colonic inflammation caused by sennoside A in Daio (rhubarb). Previously, we showed that the laxative effect of sennoside A is related to decreased aquaporin-3 (AQP3) expression in mucosal epithelial cells due to colonic inflammation. We also found that a combination of glycyrrhizin, an ingredient in Kanzo (glycyrrhiza), and sennoside A attenuates the inflammatory response induced by sennoside A and reduces its laxative effect. These findings indicate that DKT may be a long-term treatment for chronic constipation, but there is no evidence supporting this hypothesis. In this study, we analyzed the laxative effect of repeated DKT administration, focusing on AQP3 expression in the colon. After rats were treated for 7 days, decreased AQP3 expression and the onset of diarrhea were observed in the DKT group, but were not seen in the Daio group either. Although the relative abundance of gut microbiota after repeated DKT administration was similar to that after control treatment, Daio reduced Lactobacillaceae, Bifidobacteriaceae, and Bacteroidaceae levels and markedly increased Lachnospiraceae levels. In this study, we show that DKT has a sustained laxative effect, even upon repeated use, probably because it maintains decreased AQP3 expression and gut microbiota homeostasis. This outcome therefore indicates that DKT can be used as a long-term treatment for chronic constipation.

Safety of hydroxyanthracene derivatives for use in food

The Panel on Food Additives and Nutrient Sources added to Food (ANS) was asked to deliver a scientific opinion on the safety of hydroxyanthracene derivatives and to provide advice on a daily intake that does not give rise to concerns about harmful effects to health. Hydroxyanthracene derivatives are a class of chemical substances naturally occurring in different botanical species and used in food to improve bowel function. The ANS Panel reviewed the available scientific data on a possible relationship between hydroxyanthracene derivatives exposure and genotoxic and carcinogenic effects. On the basis of the data currently available, the Panel noted that emodin, aloe-emodin and the structurally related substance danthron have shown evidence of in vitro genotoxicity. Aloe extracts have also been shown to be genotoxic in vitro possibly due to the presence of hydroxyanthracene derivatives in the extract. Furthermore, aloe-emodin was shown to be genotoxic in vivo and the whole-leaf aloe extract and the structural analogue danthron were shown to be carcinogenic. Epidemiological data suggested an increased risk for colorectal cancer associated with the general use of laxatives, several of which contain hydroxyanthracene derivatives. Considering the possible presence of aloe-emodin and emodin in extracts, the Panel concluded that hydroxyanthracene derivatives should be considered as genotoxic and carcinogenic unless there are specific data to the contrary, such as for rhein, and that there is a safety concern for extracts containing hydroxyanthracene derivatives although uncertainty persists. The Panel was unable to provide advice on a daily intake of hydroxyanthracene derivatives that does not give rise to concerns about harmful effects to health.

Constipation management in people with intellectual disability: A systematic review

BACKGROUND

Constipation can lead to serious health issues and death. This systematic review summarizes international research pertaining to the management of constipation in people with intellectual disability.

METHOD

Studies published from 1990 to 2017 were identified using Medline, Cinahl, PsycINFO, Web of Science, email requests and cross-citations. Studies were reviewed narratively in relation to identified themes.

RESULTS

Eighteen studies were reviewed in relation to three themes: laxative receipt; interventions (dietary fibre, abdominal massage and macrogol); and staff issues (knowledge and training). Laxative polypharmacy was common. Studies report positive results for dietary fibre and abdominal massage although study quality was limited.

CONCLUSION

The main management response to constipation in people with intellectual disability is laxative use despite limited effectiveness. An improved evidence base is required to support the suggestion that an individualized, integrated bowel management programme may reduce constipation and associated health conditions in people with intellectual disability.

The medical complications associated with purging

OBJECTIVE

Purging behaviors, including self-induced vomiting, laxative abuse, and diuretic abuse, are present across many of the eating disorders. Here we review the major medical complications of these behaviors.

METHOD

Although we identified over 100 scholarly articles describing medical complications associated with purging, most papers involved case studies or small, uncontrolled samples. Given the limited evidence base, we conducted a qualitative (rather than systematic) review to identify medical complications that have been attributed to purging behaviors.

RESULTS

Medical conditions affecting the teeth, esophagus, gastrointestinal system, kidneys, skin, cardiovascular system, and musculoskeletal system were identified, with self-induced vomiting causing the most medical complications.

DISCUSSION

Purging behavior can be associated with severe medical complications across all body systems. Mental health professionals should refer patients with purging behaviors to medical providers for screening and treatment as needed. The medical work-up for individuals with eating disorders should include a comprehensive metabolic panel, complete blood count, and a full body exam including the teeth to prevent severe complications. Medical providers should screen patients for purging behaviors and associated medical complications, even in the absence of an eating disorder diagnosis, to increase the detection of eating disorders. Recognizing the link between purging and medical complications can aid in identifying potential eating disorders, particularly those that often elude detection such as purging disorder.

Lubiprostone increases spontaneous bowel movement frequency and quality of life in patients with chronic idiopathic constipation

BACKGROUND & AIMS

Lubiprostone is an activator of the type 2 chloride channel that facilitates spontaneous bowel movement (SBM). We performed phase 3 studies to determine whether lubiprostone increases the frequency of SBM in patients with chronic idiopathic constipation (CIC) in Japan, and whether long-term administration of lubiprostone increases the quality of life of patients with CIC.

METHODS

We performed a randomized, double-blind, placebo-controlled, phase 3 trial of lubiprostone. Patients with CIC (n = 124) were assigned randomly to groups given placebo (n = 62) or lubiprostone (48 μg/day; n = 62) for 4 weeks. The primary efficacy end point was the change from baseline in the weekly average number of SBMs after 1 week of administration. In a long-term study of efficacy and safety, 209 patients with CIC were given lubiprostone (24 μg twice daily) for 48 weeks.

RESULTS

Daily administration of lubiprostone induced a significantly greater change, from baseline, in the weekly average number of SBMs at week 1 (increase of 3.7 ± 2.8), compared with placebo (increase of 1.3 ± 1.8; P < .001). The frequency of SBMs during each week of the study period was significantly higher after subjects began receiving lubiprostone than at baseline (P < .0001 at all weeks). Long-term administration of lubiprostone significantly increased scores from the Short-Form health survey and irritable bowel syndrome quality-of-life questionnaire, compared with baseline. We did not observe any severe adverse reactions to lubiprostone.

CONCLUSIONS

In phase 3 studies in Japan, lubiprostone increased the weekly average number of SBMs and increased the quality of life of patients with CIC. Clinical Trial Notification of the Japanese Regulatory Authorities: 20-3296 and 20-3300.

Oats and bowel disease: a systematic literature review

Whole-grain foods such as oats may protect against colorectal cancer and have benefits on inflammatory bowel disease and coeliac disease. The present study aimed to systematically review the literature describing intervention studies that investigated the effects of oats or oat bran on risk factors for bowel disease. A literature search was conducted using Embase, Medline and the Cochrane library, which identified 654 potential articles. Thirty-eight articles describing twenty-nine studies met the inclusion criteria. Two studies carried out in participants with a history of colorectal adenomas found no effects of increased oat-bran intake on indirect risk makers for colorectal cancer. One of two interventions with oat bran in patients with ulcerative colitis showed small improvements in the patients' conditions. Most of the eleven studies carried out in adults with coeliac disease showed no negative effects of uncontaminated oat consumption. The fourteen studies carried out in volunteers with no history of bowel disease suggest that oats or oat bran can significantly increase stool weight and decrease constipation, but there is a lack of evidence to support a specific effect of oats on bowel function compared with other cereals. A long-term dietary intake of oats or oat bran could benefit inflammatory bowel disorders, but this remains to be proven. A protective effect on colorectal adenoma and cancer incidence has not yet been convincingly shown. The majority of patients with coeliac disease could consume up to 100 g/d of uncontaminated oats, which would increase the acceptability of, and adherence to, a gluten-free diet.

Editorial: Constipation and colorectal cancer risk: a continuing conundrum

There are conflicting data regarding the association between bowel movement frequency, constipation, and colorectal cancer (CRC). In this issue, Citronberg et al. present data from a large prospective study that was designed to examine this issue. In addition to examining bowel habits, these authors included information about the participants' laxative use, distinguishing between fiber and non-fiber-based laxatives. The investigators also collected data with respect to CRC risk factors including demographics, family history, lower endoscopy exposure, smoking, medication use, and detailed dietary information. The results demonstrated no relationship between bowel movement frequency or constipation and CRC. The authors also observed an increased CRC risk in patients who were in either the low or high non-fiber laxative use groups as compared with individuals who never used these agents (low risk: hazard ratio (HR)=1.49; and high risk: HR=1.43; Ptrend=0.05). Conversely, there was a statistically significant lower risk for those patients who reported a high use of fiber laxatives (HR=0.44, 95% confidence interval: 0.21-0.95) as compared with the nonuse group. These data have implications for physicians who treat patients with constipation.

A prospective study of the effect of bowel movement frequency, constipation, and laxative use on colorectal cancer risk

OBJECTIVES

Constipation and laxative use have been hypothesized to increase colorectal cancer (CRC) risk, but existing epidemiologic studies have been inconclusive. To address this issue, the authors prospectively examined the association between CRC incidence and constipation, non-fiber laxative use, and fiber laxative use among 75,214 participants of the VITamins And Lifestyle study.

METHODS

Information on bowel movement frequency as well as average 10-year non-fiber laxative use, fiber laxative use, and constipation was ascertained by means of a questionnaire. Patients were followed from the time of receipt of the baseline questionnaire (2000-2002) until 2008 for CRC incidence, over which time 558 incident CRC cases occurred. Cox proportional hazard models were used to estimate the multivariate-adjusted hazard ratios (HRs) and 95% confidence intervals (95% CI).

RESULTS

Compared with individuals who used non-fiber laxatives less than once per year, the HRs associated with low (1-4 times per year) and high (≥5 times per year) use were 1.49 (95% CI: 1.04-2.14) and 1.43 (95% CI: 0.82-2.28), respectively (Ptrend=0.05). HRs for CRC were statistically significantly decreased and lowest in individuals who reported using fiber laxatives often (4+ days per week for 4+ years) vs. those who reported no use (HR=0.44; 95% CI: 0.21-0.95), although the trend was not significant (Ptrend=0.19). No statistically significant associations between bowel movement frequency or constipation and CRC risk were observed.

CONCLUSIONS

Findings from this study suggest that risk for CRC increases with non-fiber laxative use and decreases with fiber laxative use. However, further observational and experimental studies are needed to clarify these relationships before drawing conclusions about the preferred treatment of constipation.

Risk of developing colorectal cancer and benign colorectal neoplasm in patients with chronic constipation

BACKGROUND

Chronic constipation (CC) is a highly prevalent health problem, potentially associated with increased risk of colorectal cancer (CRCancer).

AIM

To investigate the association between CC, its severity, and CRCancer by estimating the relative risk of developing CRCancer and benign colorectal neoplasm (BCN) among severity-stratified patients with and without CC.

METHODS

Chronic constipation patients from a large retrospective US claims database were matched 1:3 with CC-free controls by demographic characteristics. CRCancer and BCN prevalence were measured over 1 year. In pre-index CRCancer- and BCN-free patients, incidence rate ratios (IRRs) of new CRCancer and BCN were calculated. Multivariate regression models adjusted for comorbidities and family history. CC patients' disease severity was rated based on CC-related resource use. IRRs for new CRCancer and BCN were estimated for CC severity groups and controls.

RESULTS

Chronic constipation (N = 28,854) and CC-free (N = 86,562) patients had mean age 61.9 years; 66.7% were female. One-year CRCancer prevalence was 2.7% and 1.7%, and BCN prevalence was 24.8% and 11.9% for CC and CC-free patients, respectively. Adjusted IRRs between CC and CC-free patients were 1.59 [95% confidence interval (CI): 1.43-1.78] and 2.60 [95% CI: 1.51-2.70] for CRCancer and BCN, respectively. Patients with severe and very severe CC had significantly greater incidence of CRCancer and BCN. At ≥ 2 and ≥ 5 years of observation, CRCancer and BCN incidence remained consistently and significantly higher for CC patients.

CONCLUSIONS

Patients with chronic constipation are associated with significantly higher prevalence and incidence of colorectal cancer and benign colorectal neoplasm than matched chronic constipation-free patients. These risks increase with the severity of chronic constipation.

Effects of Low-frequency Current Sacral Dermatome Stimulation on Idiopathic Slow Transit Constipation

[Purpose] This study aimed to determine whether low-frequency current therapy can be used to reduce the symptoms of idiopathic slow transit constipation (ISTC). [Subjects] Fifteen patients (ten male and five female) with idiopathic slow transit constipation were enrolled in the present study. [Results] Bowel movements per day, bowel movements per week, and constipation assessment scale scores significantly improved after low-frequency current simulation of S2-S3. [Conclusion] Our results show that stimulation with low-frequency current of the sacral dermatomes may offer therapeutic benefits for a subject of patients with ISTC.

Inverse association of colorectal cancer prevalence to serum levels of perfluorooctane sulfonate (PFOS) and perfluorooctanoate (PFOA) in a large Appalachian population

Background

Perfluorooctanoate (PFOA) and perfluorooctane sulfonate (PFOS) are persistent environmental contaminants that affect metabolic regulation, inflammation, and other factors implicated in the development and progression of colorectal cancer (CRC). However, the link between these compounds and CRC remains unknown. In this cross-sectional study, we investigated the association of CRC diagnosis to PFOA and PFOS blood levels in a large Appalachian population.

Methods

Participants were 47,359 adults ≥ 21 years of age and residing in six PFOA-contaminated water districts in the mid-Ohio Valley (N = 47,151 cancer-free adults, 208 cases of primary CRC). All participants completed a comprehensive health survey between 2005 and 2006; serum levels of PFOA, PFOS, and a range of other blood markers were also measured. Medical history was assessed via self report and cancer diagnosis confirmed via chart review.

Results

CRC showed a strong inverse, dose–response association with PFOS serum levels (odds ratio (OR) adjusted for potential confounders = 0.2, 95% confidence interval (CI) 0.2,0.3) for highest vs. lowest quartile of PFOS, P-trend < 0.00001) and a significant, but more modest inverse association with PFOA (adjusted OR = 0.6 (CI 0.4, 0.9) for highest vs. lowest quartile, P-trend = 0.001). These inverse associations were stronger in those diagnosed within the previous 6 years and resident in the same water district for a minimum of 10–15 years preceding assessment. The relationship between PFOA and CRC was also more pronounced in men and leaner adults, and showed a stronger linear trend at lower exposure levels.

Conclusions

In this large cross-sectional study, we found a strong, inverse association between PFOS and likelihood of CRC diagnosis and a significant, although more modest inverse association between PFOA and CRC. If confirmed in prospective investigations, these findings may aid in identifying new strategies for CRC prevention and treatment and inform future studies regarding mechanisms underlying CRC pathogenesis.

The risk of cancer in patients with benign anal lesions: a nationwide population-based study

OBJECTIVE

To evaluate the risk of cancer among patients diagnosed with hemorrhoids and benign anal inflammatory lesions.

METHODS

A population-based, retrospective cohort study was conducted that included patients diagnosed with hemorrhoids or benign inflammatory anal lesions (eg, anal fissure, fistula, and perianal abscesses) that were registered in the National Health Insurance Research Database in Taiwan between January 1, 2000 and December 31, 2010. Standardized incidence ratios (SIRs) were calculated to compare the cancer incidence of these patients to the general population.

RESULTS

During a median observation period of 6.23 years, 3080 cancers developed among 70,513 hemorrhoid patients, with a follow-up period of 438,425.6 person-years, entailing the SIR of 1.52 (95% confidence interval [CI], 1.47-1.58). Increased cancer risk (SIR 1.16; 95% CI, 1.11-1.21) was still noted even after excluding the first year of observation. Significant long-term risk for colorectal cancer (SIR 1.50; 95% CI, 1.35-1.66) and prostate cancer (SIR 1.40; 95% CI, 1.17-1.66) was observed after corrections were made for multiple comparisons. In contrast, there was no remarkable increase in cancer risk for patients with inflammatory anal lesions when cancers detected within the first year of diagnosis were excluded.

CONCLUSION

The presence of hemorrhoids is associated significantly with a long-term risk of developing colorectal cancer or prostate cancer. In contrast, benign inflammatory anal lesions do not appear to increase the risk of malignancy.

Investigation of clinical manifestations in korean colorectal cancer patients

Purpose

Early diagnostic work-up in patients with clinical symptoms of colorectal cancer (CRC) is important to achieve good treatment results. In this study, we investigated clinical symptoms when a diagnosis of CRC was made in patients who had a surgical resection, especially focusing on the relevance of constipation to CRC.

Methods

The clinical symptoms of 17,415 CRC patients who had curative surgery from January 2010 to December 2012 were collected from 24 training hospitals of surgery.

Results

The number of symptomatic patients before the diagnosis of CRC was 11,085 (63.7%). Hematochezia or melena, abdominal pain, anemia, and constipation were more often found in female than male patients while bowel habit change was more common in male patients. Considering age, bowel habit change and hematochezia or melena were more common in patients younger than 60. Anemia and constipation, however, were more common in patients older than 60. According to the group classification based on age, patients older than 60 had experienced more constipation (P = 0.049). Moreover, patients with constipation tended to have a more advanced disease status (P < 0.001).

Conclusion

In patients who had surgery due to CRC, bleeding, abdominal pain, bowel habit change and constipation were the most frequent symptoms before diagnosis. Although whether or not constipation is a cause of CRC is unclear, it is one of the important clinical symptoms that presents in patients with CRC, and patients with a symptom of constipation tend to present with a more advanced CRC stage.

Association between constipation and colorectal cancer: systematic review and meta-analysis of observational studies

OBJECTIVES

Constipation is common in the community, and may affect survival adversely. An association between constipation and development of colorectal cancer (CRC) could be one possible explanation. We performed a systematic review and meta-analysis examining this issue.

METHODS

We searched MEDLINE, EMBASE, and EMBASE Classic (through July 2012). Eligible studies were cross-sectional surveys, cohort studies, or case-control studies reporting the association between constipation and CRC. For cross-sectional surveys and cohort studies, we recorded number of subjects with CRC according to the constipation status, and for case-control studies, number of subjects with constipation according to CRC status were recorded. Study quality was assessed according to published criteria. Data were pooled using a random effects model, and the association between CRC and constipation was summarized using an odds ratio (OR) with a 95% confidence interval (CI).

RESULTS

The search strategy identified 2,282 citations, of which 28 were eligible. In eight cross-sectional surveys, presence of constipation as the primary indication for colonoscopy was associated with a lower prevalence of CRC (OR=0.56; 95% CI 0.36-0.89). There was a trend toward a reduction in odds of CRC in constipation in three cohort studies (OR=0.80; 95% CI 0.61-1.04). The prevalence of constipation in CRC was significantly higher than in controls without CRC in 17 case-control studies (OR=1.68; 95% CI 1.29-2.18), but with significant heterogeneity, and possible publication bias.

CONCLUSIONS

Prospective cross-sectional surveys and cohort studies demonstrate no increase in prevalence of CRC in patients or individuals with constipation. The significant association observed in case-control studies may relate to recall bias.

Regression of ductal carcinoma in situ after treatment with acupuncture

This report describes a case of ductal carcinoma in situ (DCIS) that regressed after treatment with acupuncture, Chinese herbs, and other complementary and alternative medicine (CAM). The natural history of DCIS remains to be elucidated, and it is unclear whether all DCIS cases progress to invasive breast cancer. Surgery plus radiation therapy or mastectomy is recommended for women in whom this potentially nonprogressive cancer is detected. This case supports the developing trend toward active surveillance in lieu of breast-disfiguring surgery and offers evidence that CAM therapies may be of value in preventing progression of DCIS to invasive breast cancer.

Structure analysis and laxative effects of oligosaccharides isolated from bananas

Banana oligosaccharides (BOS) were extracted with water, and then separated and purified using column chromatography. Gel penetration chromatography was used to determine the molecular weights. Thin layer chromatogram and capillary electrophoresis were employed to analyze the monosaccharide composition. The indican bond and structure of the BOS molecule were determined using Fourier transform infrared spectroscopy and nuclear magnetic resonance. Results showed that BOS were probably composed of eight β-D-pyran glucose units linked with 1→6 indican bonds. The laxative effects of BOS were investigated in mice using the method described in "Handbook of Technical Standards for Testing and Assessment of Health Food in China." The length of the small intestine over which a carbon suspension solution advanced in mice treated with low-, middle-, and high-dose BOS was significantly greater than that in the model group, suggesting that BOS are effective in accelerating the movement of the small intestine.

Prospective cohort studies of bowel movement frequency and laxative use and colorectal cancer incidence in US women and men

PURPOSE

The associations between bowel movement frequency, laxative use, and colorectal cancer incidence remain uncertain. No published studies have accounted for potential latency between these factors and colorectal cancer onset.

METHODS

We prospectively examined these associations among 88,173 women in the Nurses' Health Study (NHS, 1982-2010) and 23,722 men in the Health Professionals Follow-up Study (HPFS, 2000-2010). Cox proportional hazards regression models were used to estimate multivariable hazard ratios (HRs, 95 % CIs). We conducted time lagged analyses to evaluate the potential latency in the NHS.

RESULTS

We documented 2,012 incident colorectal cancer cases. The HRs (95 % CIs) for infrequent bowel movement relative to daily were 0.86 (95 % CI 0.71-1.04) in women and 0.81 (95 % CI 0.48-1.37) in men. The HRs for weekly to daily relative to never laxative use were 0.98 (95 % CI 0.81-1.20) in women and 1.41 (95 % CI 0.96-2.06) in men. In women, the HRs for every 3 days or less bowel movement relative to daily were 0.87 (95 % CI 0.59-1.27) for colorectal cancers that developed within 10 years of assessment, 1.03 (95 % CI 0.85-1.26) for 11-18 years after assessment, and 0.73 (95 % CI 0.54-1.01) for 19-28 years after assessment. The corresponding HRs for weekly to daily relative to never laxative use were 0.93 (95 % CI 0.63-1.37), 1.03 (95 % CI 0.74-1.44), and 0.98 (95 % CI 0.71-1.35), respectively.

CONCLUSION

Bowel movement frequency and laxative use appear not to be associated with colorectal cancer risk in this study.

Effect of dietary fiber on constipation: A meta analysis

AIM: To investigate the effect of dietary fiber intake on constipation by a meta-analysis of randomized controlled trials (RCTs).

METHODS: We searched Ovid MEDLINE (from 1946 to October 2011), Cochrane Library (2011), PubMed for articles on dietary fiber intake and constipation using the terms: constipation, fiber, cellulose, plant extracts, cereals, bran, psyllium, or plantago. References of important articles were searched manually for relevant studies. Articles were eligible for the meta-analysis if they were high-quality RCTs and reported data on stool frequency, stool consistency, treatment success, laxative use and gastrointestinal symptoms. The data were extracted independently by two researchers (Yang J and Wang HP) according to the described selection criteria. Review manager version 5 software was used for analysis and test. Weighted mean difference with 95%CI was used for quantitative data, odds ratio (OR) with 95%CI was used for dichotomous data. Both I² statistic with a cut-off of ≥ 50% and the χ² test with a P value < 0.10 were used to define a significant degree of heterogeneity.

RESULTS: We searched 1322 potential relevant articles, 19 of which were retrieved for further assessment, 14 studies were excluded for various reasons, five studies were included in the analysis. Dietary fiber showed significant advantage over placebo in stool frequency (OR = 1.19; 95%CI: 0.58-1.80, P < 0.05). There was no significant difference in stool consistency, treatment success, laxative use and painful defecation between the two groups. Stool frequency were reported by five RCTs, all results showed either a trend or a significant difference in favor of the treatment group, number of stools per week increased in treatment group than in placebo group (OR = 1.19; 95%CI: 0.58-1.80, P < 0.05), with no significant heterogeneity among studies (I²= 0, P = 0.77). Four studies evaluated stool consistency, one of them presented outcome in terms of percentage of hard stool, which was different from others, so we included the other three studies for analysis. Two studies reported treatment success. There was significant heterogeneity between the studies (P < 0.1, I² > 50%). Three studies reported laxative use, quantitative data was shown in one study, and the pooled analysis of the other two studies showed no significant difference between treatment and placebo groups in laxative use (OR = 1.07; 95%CI 0.51-2.25), and no heterogeneity was found (P = 0.84, I²= 0). Three studies evaluated painful defecation: one study presented both quantitative and dichotomous data, the other two studies reported quantitative and dichotomous data separately. We used dichotomous data for analysis.

CONCLUSION: Dietary fiber intake can obviously increase stool frequency in patients with constipation. It does not obviously improve stool consistency, treatment success, laxative use and painful defecation.

Concurrent conditions in patients with chronic constipation: a population-based study

Background

Chronic constipation (CC) is a common condition but its concurrent conditions are not well characterized. We measured the prevalence and risk of developing 15 pre–specified concurrent conditions in patients with CC.

Methods

Retrospective cohort study using the Medicaid database of California, utilizing ICD-9 codes for detection of cases (CC), controls (patients with GERD) and concurrent conditions. Study period was 01/01/1995 to 06/30/2005. Index date was the date 3 months before the first physician visit for CC. Pre-index time (12 months) was compared to post-index time (12 months) to assess the association of every concurrent condition within each cohort. To account for ascertainment bias, an adjusted odds ratio was calculated by comparing the odds ratio for every concurrent condition in the CC cohort to that in the GERD cohort.

Results

147,595 patients with CC (mean age 54.2 years; 69.7% women; 36.2% white) and 142,086 patients with GERD (mean age 56.3 years; 65.3% women; 41.6% white) were evaluated. The most prevalent concurrent conditions with CC were hemorrhoids (7.6%), diverticular disease (5.9%), ano–rectal hemorrhage (4.7%), irritable bowel syndrome (3.5%) and fecal impaction (2%). When adjusted for ascertainment bias, the most notable associations with CC were Hirschsprung's disease, fecal impaction and ano-rectal conditions such as fissure, fistula, hemorrhage and ulcers.

Conclusion

Chronic constipation is associated with several concurrent conditions of variable risk and prevalence. To reduce the overall burden of CC, these concurrent conditions need to be addressed.

Diagnostic yield of colonoscopy for constipation as the sole indication

AIM

There is controversy over whether constipation as the only symptom should be an indication for routine diagnostic colonoscopy. The study was carried out to assess the prevalence of abnormal pathology on colonoscopy and to assess the risk factors for colonic neoplasia in patients with constipation but without 'high risk symptoms'.

METHOD

A cross-sectional, single-centre study was conducted on individuals who underwent colonoscopy for constipation as the sole indication between 2005 and 2008. Standardized endoscopic and pathology reports were reviewed. Univariable and multivariable analyses were performed.

RESULTS

A total of 786 patients (595 women, 75.7%; mean age, 57.4±13.5 years) underwent diagnostic colonoscopy for constipation. Forty-three (5.5%) had polyps, of whom 19 (2.4%) had hyperplastic polyps and 19 (2.4%) adenomas. No cancers were found. In patients with adenoma, the detection rate was 2.9% for patients below age 40 years and 1.7% for patients below age 50 years. Older age was associated with a polyp in both univariate and multivariate analysis. Gender, ethnicity and smoking were not associated with polyp or adenoma.

CONCLUSION

Colonoscopy for patients with constipation as the sole indication had a lower yield of neoplastic lesions than that for patients undergoing routine screening colonoscopy. Colonoscopy in constipation may only be warranted in patients who are over 50 years of age.

Efficacy and safety of oral lubiprostone in constipated patients with or without irritable bowel syndrome: a randomized, placebo-controlled and dose-finding study

BACKGROUND

Lubiprostone is a prostone analog with a novel mechanism of action involving type-2 chloride channel activation. The aim of this work was to perform a dose-finding study for lubiprostone for the treatment of constipation with or without irritable bowel syndrome (IBS) in Japan.

METHODS

A total of 170 patients (128 without IBS and 42 with IBS) with chronic idiopathic constipation (CIC) randomly received a placebo (n=42) or 16μg (n=41), 32μg (n=43), or 48μg (n=44) of lubiprostone daily for 2weeks.

KEY RESULTS

There was a statistically significant and dose-dependent increase in change from baseline in the weekly average number of spontaneous bowel movements at week 1 (placebo: 1.5±0.4; 16μg: 2.3±0.4, 32μg: 3.5±0.5; and 48μg: 6.8±1.1, per week, mean±SE; P<0.0001). These primary endpoint results were significant on stratified analysis when patients were limited to those without IBS (P<0.0001). The primary endpoint in patients with IBS treated with 48μg of lubiprostone was significantly better than those given placebo (P=0.0086). Dose dependency was also seen for the secondary efficacy endpoints. Lubiprostone produced no serious side effects.

CONCLUSIONS & INFERENCES

Our results suggest that lubiprostone produced a steady and effective improvement in the symptoms of CIC with or without IBS in a dose-dependent manner with a good safety profile and tolerability in a Japanese population.

Most bowel cancer symptoms do not indicate colorectal cancer and polyps: a systematic review

BACKGROUND

Bowel symptoms are often considered an indication to perform colonoscopy to identify or rule out colorectal cancer or precancerous polyps. Investigation of bowel symptoms for this purpose is recommended by numerous clinical guidelines. However, the evidence for this practice is unclear. The objective of this study is to systematically review the evidence about the association between bowel symptoms and colorectal cancer or polyps.

METHODS

We searched the literature extensively up to December 2008, using MEDLINE and EMBASE and following references. For inclusion in the review, papers from cross sectional, case control and cohort studies had to provide a 2×2 table of symptoms by diagnosis (colorectal cancer or polyps) or sufficient data from which that table could be constructed. The search procedure, quality appraisal, and data extraction was done twice, with disagreements resolved with another reviewer. Summary ROC analysis was used to assess the diagnostic performance of symptoms to detect colorectal cancer and polyps.

RESULTS

Colorectal cancer was associated with rectal bleeding (AUC 0.66; LR+ 1.9; LR- 0.7) and weight loss (AUC 0.67, LR+ 2.5, LR- 0.9). Neither of these symptoms was associated with the presence of polyps. There was no significant association of colorectal cancer or polyps with change in bowel habit, constipation, diarrhoea or abdominal pain. Neither the clinical setting (primary or specialist care) nor study type was associated with accuracy.Most studies had methodological flaws. There was no consistency in the way symptoms were elicited or interpreted in the studies.

CONCLUSIONS

Current evidence suggests that the common practice of performing colonoscopies to identify cancers in people with bowel symptoms is warranted only for rectal bleeding and the general symptom of weight loss. Bodies preparing guidelines for clinicians and consumers to improve early detection of colorectal cancer need to take into account the limited value of symptoms.

Bowel movement and constipation frequencies and the risk of colorectal cancer among men in the Netherlands Cohort Study on Diet and Cancer

The authors investigated the associations between bowel movement and constipation frequencies and colorectal cancer (CRC) endpoints among men in the Netherlands Cohort Study on Diet and Cancer (n = 58,279) and explored whether dietary fiber intake may modify associations. After 13.3 years (1986-1999), 1,207 CRC cases and 1,753 subcohort members were available for case-cohort analyses. Multivariate analyses showed a significantly increased hazard ratio for CRC overall and rectal cancer in men who reported having a bowel movement 1-2 times per day (second-highest category) as compared with once a day (CRC: hazard ratio (HR) = 1.29, 95% confidence interval (CI): 1.09, 1.53 (P(trend) < 0.001); rectal cancer: HR = 1.50, 95% CI: 1.15, 1.95 (P(trend) = 0.001)). Hazard ratios for CRC overall and rectal cancer were significantly decreased and lowest in men who reported suffering from constipation sometimes or more often versus never (CRC: HR = 0.76, 95% CI: 0.58, 0.98 (P(trend) = 0.02); rectal cancer: HR = 0.57, 95% CI: 0.35, 0.90 (P(trend) = 0.01)). No trends in the associations with proximal or distal colon cancer risk were observed. Interactions with dietary fiber intake were not significant. In this study, frequent bowel movements were associated with an increased risk of rectal cancer in men, and constipation was associated with a decreased risk.