Chronic constipation diagnosis and treatment evaluation: the “CHRO.CO.DI.T.E.” study
© The Author(s). 2017
Received: 19 July 2016
Accepted: 6 December 2016
Published: 14 January 2017
According to Rome criteria, chronic constipation (CC) includes functional constipation (FC) and irritable bowel syndrome with constipation (IBS-C). Some patients do not meet these criteria (No Rome Constipation, NRC). The aim of the study was is to evaluate the various clinical presentation and management of FC, IBS-C and NRC in Italy.
During a 2-month period, 52 Italian gastroenterologists recorded clinical data of FC, IBS-C and NRC patients, using Bristol scale, PAC-SYM and PAC-QoL questionnaires. In addition, gastroenterologists were also asked to record whether the patients were clinically assessed for CC for the first time or were in follow up. Diagnostic tests and prescribed therapies were also recorded.
Eight hundred seventy-eight consecutive CC patients (706 F) were enrolled (FC 62.5%, IBS-C 31.3%, NRC 6.2%). PAC-SYM and PAC-QoL scores were higher in IBS-C than in FC and NRC. 49.5% were at their first gastroenterological evaluation for CC. In 48.5% CC duration was longer than 10 years. A specialist consultation was requested in 31.6%, more frequently in IBS-C than in NRC. Digital rectal examination was performed in only 56.4%. Diagnostic tests were prescribed to 80.0%. Faecal calprotectin, thyroid tests, celiac serology, breath tests were more frequently suggested in IBS-C and anorectal manometry in FC. More than 90% had at least one treatment suggested on chronic constipation, most frequently dietary changes, macrogol and fibers. Antispasmodics and psychotherapy were more frequently prescribed in IBS-C, prucalopride and pelvic floor rehabilitation in FC.
Patients with IBS-C reported more severe symptoms and worse quality of life than FC and NRC. Digital rectal examination was often not performed but at least one diagnostic test was prescribed to most patients. Colonoscopy and blood tests were the “first line” diagnostic tools. Macrogol was the most prescribed laxative, and prucalopride and pelvic floor rehabilitation represented a “second line” approach. Diagnostic tests and prescribed therapies increased by increasing CC severity.
KeywordsFunctional constipation Irritable bowel syndrome Diagnosis Treatment
Chronic constipation (CC) is a common and extremely troublesome disorder that has a negative impact on social and professional life, reduces the quality of life (QoL) and represents a heavy economic burden [1–5]. CC affects about 12–17% of the world population, with a higher prevalence among females and elderly people [6–9].
A considerable amount (16 to 40%) of CC patients in different countries use laxatives, and their use is related to increasing age, symptom frequency and duration of constipation; in the USA more than $800 million are spent on laxatives each year [10, 11].
Rome III criteria for functional constipation and irritable bowel syndrome
Diagnostic criteria a
1. Must include two or more of the following:
α. Straining during at least 25% of defecations
β. Lumpy or hard stools in at least 25% of defecations
γ. Sensation of incomplete evacuation for at least 25% of defecations
δ. Sensation of anorectal obstruction/blockage for at least 25% of defecations
ε. Manual manoeuvres to facilitate at least 25% of defecations (e.g. digital evacuation, support of the pelvic floor)
η. Fewer than three defecations per week
2. Loose stools are rarely present without the use of laxatives
3. Insufficient criteria for irritable bowel syndrome
aCriteria fulfilled for the last 3 months with symptoms onset at least 6 months prior to diagnosis
Irritable Bowel Syndrome with Constipation
Diagnostic criteria a
Recurrent abdominal pain or discomfort b at least 3 days/month in the last 3 months associated with two or more of the following:
-Improvement with defecation
-Onset associated with a change in frequency of stool
-Onset associated with a change in form (appearance) of stool (hard or lumpy stools ≥25% and loose or watery stools <25% of bowel movements)
At present it is unclear whether gastroenterologists use the same diagnostic and therapeutic approach in these different groups of patients.
Objective of the study
To describe the diagnostic tools used and the treatments suggested by Italian gastroenterologists for CC patients.
To assess, among CC patients, the distribution of FC, IBS-C and NRC and the severity of symptoms and QoL.
To evaluate whether the diagnosis of FC, IBS-C and NRC could affect the use of the diagnostic tools and the choice of the therapy.
To evaluate other possible potential factors affecting the use of the diagnostic tools and the therapeutic choices in CC patients.
Study population and questionnaires
Fifty two gastroenterologists belonging to different gastroenterological units in Italy on behalf of the Italian Association of Hospital Gastroenterologists and Endoscopists (AIGO), recorded clinical and demographic data of all patients consecutively referred for CC in a two month period (September-October 2013).
Bristol scale  was used to assess the stool consistency in the previous three months, while symptoms were classified according to Rome III criteria in order to verify whether the patients could be diagnosed as FC, IBS-C, or NRC. In addition, gastroenterologists were also asked to record whether the patients were clinically assessed for CC for the first time or were in follow up. Diagnostic tests, recommended specialist consultations and prescribed therapies were also recorded.
Furthermore, patients were required to fill the Patient Assessment of Constipation-Symptoms (PAC-SYM) and the Patient Assessment of Constipation-Quality of Life (PAC-QoL) questionnaires.
PAC-SYM is a 12-item self-reported questionnaire developed to assess the frequency and severity of CC symptoms. It is divided into three symptom subscales: abdominal (items 1–4), rectal (items 5–7), and stool (items 8–12) .
PAC-QoL is a 28 item self-reported questionnaire used to measure the patient’s QoL. It is divided into four subscales: physical discomfort (items 1–4), psychosocial discomfort (items 5–12), worries and concerns (items 12–23), and satisfaction (items 24–28) .
For both questionnaires, items are scored on a five-point Likert scale (0–4), with 4 indicating the worst symptom severity.
-Patients aged over 18 years evaluated for CC.
-Presence of known or suspected severe organic disease potentially causing constipation and/or psychiatric disease potentially interfering with questionnaires compilation.
-Patients assuming potentially constipating drugs or the onset of constipation after starting any kind of drug.
Data were analyzed by means of the SAS® System for Windows, version 9.2.
A prevalence approach was adopted and no imputation was performed for any missing data.
The association between categorical variables was analyzed using Chi-Square test or Fisher’s exact test (for cell frequencies < 5). In order to correct for multiple comparisons, pairwise tests were adjusted using the Bonferroni method.
The association between a continuous and a categorical variable (with two categories) was analyzed by the Wilcoxon-Mann–Whitney test. Finally, the association between a continuous and a categorical variable was analyzed by the Kruskal-Wallis test (or by the ANOVA in case of normal distribution). In case of pairwise comparisons, the Dunn’s test was performed. The correlation between two continuous variables was summarized by the Pearson’s correlation coefficient in case of normal data distribution, or by the Spearman’s correlation coefficient otherwise.
All statistical tests were performed with a two-sided significance level α = 0.05, therefore p-values lower than 0.05 were considered statistically significant.
The PAC-SYM and PAC-QoL total and domain scores were calculated as detailed in Additional file 1, respectively.
PAC-SYM total score and PAC-QoL total score were also analyzed through multivariate regression models, adjusting for the following independent variables: age, sex, diagnosis, duration of CC.
Data from 878 CC patients (33.9% in Northern Italy, 32.4% in Center Italy and 33.7% in Southern Italy), 706 women (80.4%) and 172 men (19.6%), mean age: 51.0 ± 16.8 years (F 49.6 ± 16.6 years; M 56.9 ± 16.5 years) were obtained. Their body mass index (BMI) was 23.7 ± 4.0 kg/m2. Four hundred thirty-five out of 878 patients (49.5%) were at their first gastroenterological evaluation for CC. According to Rome III criteria the patients were classified as FC: 549 (62.5%); IBS-C: 275 (31.3%); NRC: 54 (6.2%).
IBS-C patients were younger (46.9 ± 16.2 years) than FC (52.8 ± 16.6) and NRC (53.1 ± 18.6) (p < 0.0001). The gender distribution was significantly different between the three groups (IBS-C: women 234/275 (85.1%); FC: women 433/549 (78.9%); NRC: women 39/54 (72.2%) (p < 0.05) .
The duration of CC was “>1–4 years” in 23.1% (IBS-C: 33.0%; FC: 59.1%; NRC: 7.9%), “≥5years” in 21.1% (IBS-C: 27.0%; FC: 65.4%; NRC: 7.6%) and “>10 years” in 48.5% of the patients (IBS-C: 32.2%; FC: 63.9%; NRC: 4.0%). No significant difference was observed between groups but only a trend toward a shorter duration in NRC could be detected.
Bristol 1–2 was reported in 628/878 (71.5%) patients (IBS-C: 208/275, 75.6%; FC:394/549, 71.8%; NRC: 26/54, 48.2%) (IBS-C vs FC: ns; IBS-C vs. NRC: p < 0.001; FC vs NRC: p < 0.005).
Prevalence of comorbidities
8 (14.8%)## ###
PAC-SYM total score and abdominal, rectal and faecal symptoms subscales: mean values ± SD in all patients and in IBS-C, FC and NRC subgroups
1.6 ± 0.70
1.75 ± 0.70*
1.56 ± 0.68
1.31 ± 0.70
p < 0.0001
1.53 ± 0.88
1.91 ± 0.74#§
1.37 ± 0.88
1.19 ± 0.86
p < 0.0001
0.88 ± 0.86
0.98 ± 0.92
0.85 ± 0.83
0.70 ± 0.78
2.09 ± 0.91
2.09 ± 0.88
2.13 ± 0.92
1.74 ± 0.88^
p < 0.01
PAC-QoL total score and subscales (mean values ± SD) in all patients and in IBS-C, FC and NRC subgroups
1.77 ± 0.69
1.97 ± 0.70
1.71 ± 0.68
1.44 ± 0.62*
p < 0.001
1.85 ± 0.88
2.13 ± 0.82
1.75 ± 0.88
1.42 ± 0.82*
p < 0.001
1.12 ± 0.83
1.38 ± 0.83
1.02 ± 0.80
0.77 ± 0.73*
p < 0.001
Worries and concerns
1.72 ± 0.92
1.92 ± 0.93
1.65 ± 0.90
1.36 ± 0.80*
p < 0.001
2.90 ± 0.71
2.89 ± 0.72
2.92 ± 0.69
2.74 ± 0.81
Digital rectal examination (DRE) was performed in 495/878 (56.4%), independently from the patients being at their first evaluation (54.7%) or at a follow up visit (56.6%). No relationship with gender was found (104 M: 61.3%; F 391: 55.2%). Patients in whom a DRE was performed were older (52.6 ± 16.6 years vs. 49.4 ± 16.7; p < 0.01), and DRE was more often performed by gastroenterologists aged over 40 years than by younger ones (60.1% vs. 44.6%; p < 0.0001).
Specialist consultations requested by the gastroenterologists after their visit
878 pts. (%)
Diagnostic test requested by the gastroenterologist after their visit
Routine blood tests
Thyroid function tests
Colonic transit time
Faecal blood test
Carcinoembryonic antigen assay
15.3 * **
Stool culture, test for ova and parasites
Lactose Breath Test
Glucose Breath test
Anal Sphincter Electromyography
Colonoscopy was suggested more in patients ≥50 years than in those <50 years (52.3% vs. 22.5%; p < 0.0001), more in males than in females (51.2% vs. 35.6%; p < 0.001) and more often at first evaluation than at follow-up (43.2% vs. 32.8%; p < 0.005). Also, routine blood tests (61.2% vs. 46.6%; p < 0.0001), thyroid function tests (52.0% vs. 40.2%,; p < 0.001), carcinoembryonic antigen (11.3% vs. 6.4%; p < 0.05), serology for celiac disease (19.1% vs. 13.2%; p < 0.05); and stool culture and test for ova and parasites (9.7% vs. 4.2%; p < 0.005) were requested more often at first evaluation than at follow-up. On the contrary defecography (2.5% vs. 5.6%; p < 0.05) was suggested less frequently at first visit than at follow-up. Serology for celiac disease was suggested more frequently in patients <50 years old than in patients ≥50 years old (22.0% vs. 11.3%; p < 0.0001).
Suggested therapies requested by the gastroenterologist after their visit
Life style recommendations
27.6 * **
Pelvic floor rehabilitation
Macrogol was suggested more frequently in FC (71.6%) and IBS-C (70.9%) than in NRC (42.6%; p < 0.0001). A fiber supplements prescription was slightly more frequent in IBS-C, but no significant difference was detected among IBS-C, FC and NRC. In IBS-C antispasmodics were used more frequently compared to FC and NRC (27.6% vs. 11.7% vs. 11.1%; p < 0.0001 and p > 0.05, respectively). Antibloating agents (29.1% vs. 18.6%; p < 0.005) and psychotherapy (6.9% vs. 2.7%; p < 0.05) were most frequently prescribed in IBS-C than in FC, whereas pelvic floor rehabilitation was more frequently suggested in FC than in IBS-C (22.2% vs. 14.6%; p < 0.05).
Lactulose/lactitole (8.6% vs. 4.3%; p < 0.05), suppositories/micro-enemas (26.4% vs. 18.2%; p < 0.005), intestinal antibiotics (9.0% vs. 3.0%; p < 0.0005), antidepressants (10.0% vs. 3.0%; p < 0.0001), anxiolytics (15.9% vs. 8.1; p < 0.001) and pelvic floor rehabilitation (22.0% vs. 15.7%; p < 0.05) were more frequently suggested in patients ≥50 years than in patients <50 years, whereas antispasmodics were more frequently prescribed in patients <50 years than in patients ≥50 years (20.0% vs. 13.8%; p < 0.05).
Enemas and micro-enemas/suppositories were mainly prescribed not on a daily basis but usually every other day or on demand (24.2% and 19.7%, respectively). Lifestyle changes (87.5% vs. 80.9%; p < 0.05) and dietary suggestions (91.1% vs. 83.9%; p < 0.05) were more frequently prescribed in males than in females, but anorectal surgery only in females (2.8%).
Probiotics were most frequently prescribed at first visit than at follow-up (40.9% vs. 31.5%; p < 0.01), whereas prucalopride and pelvic floor rehabilitation were more often prescribed during a follow-up visit than at first evaluation (20.1% vs. 10.6%, p < 0.0001; 23.8% vs. 15.4%, p < 0.005, respectively).
A mix of suggestions and drugs was used in many patients: in 59.5% lifestyle suggestions, changes in diet and macrogol; in 50.8% lifestyle suggestions, changes in diet and fiber supplementation; in 37.2% changes in diet, fiber supplementation and macrogol; in 37.1% lifestyle suggestions, fiber supplementation and macrogol; in 33.3% lifestyle suggestions, changes in diet and probiotics.
The present study conveys an important educational message for general practitioners, who see the majority of constipated patients, and for other specialists who could visit patients for possible comorbidities: when collecting the patient’s history, the presence of constipation should be accurately searched and treated (if possible). Waiting so many years before sending constipated patients to a gastroenterologist simply means worsening a patient’s symptoms and his/her QoL  and increasing the risk to develop important anatomical alterations such as perineal descent, rectocele, rectal intussusceptions, prolapse, enterocele or sigmoidocele, or increase his/her cardiovascular mortality .
Rome criteria seemed accurate to identify constipated patients, since only 6.2% showed NRC.
NRC patients were usually older and often male than IBS-C, and reported fewer and less severe symptoms, softer stools and a better QoL than FC and IBS-C. On the other hand, IBS-C patients were younger and more often female, reported more severe symptoms, harder stools and a worse QoL than NRC and FC. Our results show that Rome III criteria identify patients with more severe constipation.
Recently the new Rome IV criteria have been published . No substantial differences have been introduced regarding definition and classification of functional constipation: simply they state that “abdominal pain and/or bloating may be present but are not predominant symptoms (ie, the patient does not meet criteria for IBS)”. Regarding IBS the term discomfort was eliminated and the frequency of abdominal pain became at least 1 day per week instead of 3 days per month. However we think that these changes would not have a significant impact on the results of our study.
PAC-SYM and PAC-QoL questionnaires showed higher scores in IBS-C group than in FC and NRC: PAC-SYM abdominal symptom subscale, PAC-QoL mean total score, physical discomfort, psychosocial discomfort and worries and concerns subscales were found to be higher in IBS-C. This reflects the close association between the first four items of PAC-SYM (abdominal discomfort, abdominal pain, bloating, stomach cramps) and the typical symptoms of IBS. These symptoms are likely responsible for the lower QoL in IBS-C. Thus, the increase in perception of constipation severity increases impairment of the QoL, also increasing request of diagnostic tests and therapies.
Different clinical characteristics, such as type of constipation and comorbidities, may influence the clinical approach of the gastroenterologists; thus, our primary endpoint was to assess the diagnostic tools and treatment suggested by Italian gastroenterologists to their constipated patients, and the impact on the clinical subgroups.
A surprising result, deserving discussion, is that DRE was not performed in more than 40% of the patients, independently from being at first visit or at follow-up. DRE is the simplest and the most immediate method to assess anal tone and to collect information about the pelvic floor conditions and to detect early forms of rectal cancer or benign diseases [19–22]. These data should be carefully taken into account when carrying out educational campaigns on the diagnosis and treatment of CC.
The presence of comorbidities was likely the main reason for the more frequent requested consultations (psychiatric/psychological, urological, gynecological) underlining the need for a stronger collaboration among different specialists for the correct management of CC, possibly creating multidisciplinary teams.
Regarding the attitude towards diagnostic tests, we want to stress that in about four out of five patients gastroenterologists were not so confident on Rome III criteria, and prescribed at least one diagnostic test, more often in patients at first evaluation, mainly blood tests, but also colonoscopy (requested more frequently in patients older than 50 years), anorectal manometry and measurement of colonic transit time. As already shown in previous studies in a general practitioner setting, abdominal ultrasound, although not recommended by current guidelines, was quite frequently requested, especially when abdominal pain is present [23–26].
To exclude conditions potentially mimicking IBS, laboratory and breath tests were more frequently requested in these patients, whereas in FC, defecography and anorectal manometry were more frequently requested to evaluate the presence of dyssynergic defecation. In NRC patients fewer diagnostic tests were overall required, probably due to less severe symptoms and lesser impairment of the QoL.
Overall, dietetic and lifestyle suggestions were the most frequently suggested therapeutic options (>90% of the patients) (Table 7). However, in the present study, the gastroenterologists were often not confident that these could be sufficient to solve the problem and used macrogol as the first line laxative, both in association with dietetic and lifestyle suggestion and fibers.
Macrogol is effective and safe, and new liquid formulations make it easier to dose; because taste is an important factor for patients’ adherence, particularly for long-time treatment, the formulations without aroma made it more acceptable to patients . On the other hand further increasing fibers intake could induce bloating and abdominal discomfort without improving colonic transit time . To control the different symptoms of IBS (mainly abdominal pain and bloating) gastroenterologists also used antispasmodic drugs, psychotherapy and anti-bloating agents, whereas pelvic floor rehabilitation was suggested more often in FC patients, in whom functional defecation disorders should be more frequent.
Surgery procedures (and sacral neurostimulation) were infrequently suggested by gastroenterologists.
The gastroenterologists involved in this study rarely prescribed laxatives such as lactulose/lactitole, and stimulant, emollient or saline laxatives which still represent the most used laxatives in Italy. These drugs, which cover about 40% of the Italian market , are more often prescribed by general practitioners  and other specialists than gastroenterologists.
Prucalopride, recently available on the Italian market, was prescribed in about 13% of patients although it was considered, probably because expensive, a second/third line treatment, and prescribed more frequently at a follow-up. At the time of the study, linaclotide was not yet available on the Italian market.
As previously reported for diagnostic tools, the amount of therapy prescribed also increased by increasing PAC-SYM and PAC-QoL scores; in NRC patients, who displayed lighter symptoms, fewer therapies were suggested. In conclusion, in our country a gastroenterological evaluation of CC is often delayed in patients with long lasting symptoms, colonoscopy and blood tests are considered a “first line” diagnostic tool, and DRE is insufficiently performed. Furthermore, constipation is associated with several comorbidities in most patients. Among Italian gastroenterologists macrogol is the most frequently used laxative, while in IBS-C patients a larger amount of drugs is prescribed than in FC and NRC patients.
The study also provides several educational ideas to improve the diagnostic and therapeutic approach to CC: general practitioners and other specialists should be suggested to address earlier such patients to a gastroenterologist before long-term complications occur. DRE should be performed in all patients, while echography usefulness should be resized.
Chronic constipation is a common disorder that has a remarkable impact on the quality of life. We report on diagnostic and therapeutical experiences of Italian gastroenterologists.
Patients with irritable bowel syndrome with constipation reported more severe symptoms and worsened quality of life than functional constipation. Colonoscopy and blood tests were the most prescribed tests and Macrogol was the most prescribed laxative.
This study can provide several educational ideas to improve the diagnostic and therapeutic approach to Chronic Constipation.
Italian association of hospital gastroenterologists and endoscopists
Body mass index
Digital rectal examination
Irritable bowel syndrome with constipation
No Rome constipation
The patient assessment of constipation-quality of life
Patient assessment of constipation-symptoms
Quality of life.
The authors are grateful to Dr. Elena Pasquali for her valuable help in carrying out the statistical analysis.
The members of the ChroCoDiTE StudyGroup are listed in Appendix and searchable through their individual PubMed records.
Availability of data and materials
The datasets analysed during the current study are available from the corresponding author on reasonable request.
MB, PUS, GB, participated in study concept and design, data analysis, interpretation of results, manuscript drafting and approved the final version of the manuscript. AB, RB and FG contributed to the interpretation of results, provided critical revisions to manuscript drafts and approved the final version of the manuscript. EB and PA participated in study concept and design, data collection, interpretation of results, provided critical revisions to manuscript drafts and approved the final version of the manuscript. All members of the ChroCoDiTE study group participated in data collection, provided critical revisions to manuscript drafts and approved the final version of the manuscript.
The authors declare that they have no competing interests.
Consent for publication
Ethical approval and consent to participate
The study protocol was approved by the Ethical Committee of Pisa (study number 3841/2013 approved on March 21st, 2013) and was carried out in accordance with the Helsinki Declaration (Sixth Revision, Seoul 2008). A signed informed consent was obtained from each participant.
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