Prevalence of chronic constipation has been reported to range between 5% and 15% of the general population, depending on the size and type of assessment, the definition of constipation, and variables such as nationality, culture, and the health care system [
Constipation-predominant IBS (IBS-C) represents a subgroup of all IBS patients in whom abdominal pain is associated with constipation, while other predominant bowel symptoms (diarrhea, alternating diarrhea, and constipation) are labeled as IBS-D and IBS-M [
When patients with IBS-C were compared to patients with functional constipation matching or not matching Rome criteria, Rey et al. [
Constipation may also occur as a secondary symptom, for example, in a number of neurological (e.g., stroke, Parkinson’s disease, and spinal cord injury), systemic (diabetes, hypothyroidism, and scleroderma), and other disorders, to intestinal or nonintestinal surgery [
Quality-of-life (QoL) has been reported to be low in functional constipation as well as in IBS-C when assessed with both constipation-specific QoL instruments [
The purpose of the present evaluation of the German Chronic Constipation (GECCO) study data was to compare different populations with functional constipation with or without abdominal pain with respect to sociographic, clinical, and quality-of-life data. We assumed representativeness of our samples allowing conclusions on the population prevalence of the different subgroups but tested for response biases beforehand.
The aim of GECCO study was to (a) determine the prevalence of chronic constipation among adults in Germany and (b) obtain information on their quality-of-life and further medical parameters by a subsequent written survey. The prevalence data from a telephone interview with 15.000 representative adults were recently [
The 10-minute interview concluded with sociographic data (education and training, professional status, and family income). Only if constipation had been acknowledged were they asked whether they would provide a postal address for sending a more elaborate questionnaire on this topic.
The 8 pages’ (37 + 3 items) questionnaire was sent within 2 weeks following the interview. If the questionnaire was not sent back (by a prepaid envelop) within 3 weeks, a reminding letter was sent to the person to ask for completion; a second reminding letter would follow if again no response occurred within three weeks.
The questionnaire was composed of 4 modules (1: General Health; 2: Concurrent Diseases/Medication; 3: Health Care Utilization; 4: Constipation and IBS) and started with some general questions to overall health that contained the items of the Short-Form 12 (SF-12) [
Module 3 inquired about consultation of specialists in the past 12 months, sick-days because of constipation, inpatient treatment, diagnostic procedures performed, and complementary and alternative remedies taken because of CC, including the amounts spent that were not reimbursed by health insurance plans. These data will be reported in a separate paper.
Module 4 contained questions from the Rome III modular questionnaire for IBS and for functional constipation [
Final three questions referred to statistics and the willingness to participate in a future follow-up questionnaire study.
The protocol of the study methodology had been reviewed by the Ethics Committee of the Tübingen University Medical School, and the study was conducted in accordance with approved standards for epidemiological research [
Usually, response rates are reported and used without additionally checking for the representativeness of the cohort. To control for potential self-selection biases in the questionnaire data, we compared individuals with constipation who provided a postal address for sending the questionnaire to those that refused to participate with respect to the sociographic data available from the interview. We also compared those that returned the questionnaire to those that did not, using the same data set. These comparisons were done by groupwise
Constipation subsamples were constructed based on predefined criteria: patients with at least one somatic diagnosis and/or more than twice weekly intake of medication for nonconstipation reasons constituted a group labeled “constipation probably associated with a somatic condition” (= putative comorbid constipation) and were excluded from the present analysis; we will report these data in a separate paper.
Among the remaining cases, those meeting Rome III criteria for IBS (based on the algorithm provided by the Rome committee [
All data are reported as mean ± SD and are unweighted with respect to the initial representative survey. The significance level was set to 0.05 for all tests. Post hoc
During the telephone survey [
We compared the data available from the telephone survey [
Test for self-selection biases between those providing a post address for sending the questionnaire and those who did not and between those who send back the questionnaire and those who did not. Compared are the data provided during the telephone interview prior to asking for the postal address. Data are unweighted.
Questionnaire received | Questionnaire returned | |||||
---|---|---|---|---|---|---|
Yes: |
No: |
Stats |
Yes: |
No: |
Stats |
|
Personal data | ||||||
Age (mean, SD) | 51.3 ± 0.6 | 49.9 ± 0.6 | n.s. |
|
|
|
Male : female | 352 : 685 | 453 : 750 | n.s. | 201 : 388 | 151 : 297 | n.s. |
Height (m) | 1.69 ± 0.01 | 1.69 ± 0.01 | n.s. | 1.69 ± 0.01 | 1.69 + 0.01 | n.s. |
Weight (kg) | 74.6 ± 0.5 | 74.9 ± 0.2 | n.s. | 74.7 ± 0.7 | 74.5 ± 0.9 | n.s. |
BMI | 26.1 ± 0.2 | 25.9 ± 0.1 | n.s. | 26.2 ± 0.2 | 26.0 ± 0.3 | n.s. |
|
||||||
Social situation | ||||||
Education: secondary+ | 256 | 284 | n.s. | 155 | 101 |
|
Full-time/part time (1) | 375 | 449 |
1/2 versus 3/5 |
195 | 179 |
1/2 versus 3/5 |
Mini job, occasional (2) | 72 | 86 | 46 | 27 | ||
Not working, training (3) | 186 | 244 | 94 | 92 | ||
Parent time (4) | 54 | 39 | 18 | 35 | ||
Retired (5) | 347 | 379 | 234 | 113 | ||
Income: >2,500€/mo | 284 | 221 | 160 | 123 | n.s. | |
|
||||||
Life satisfaction | ||||||
Fully (1) | 309 | 350 |
1/2 versus 3/4: |
186 | 123 |
1/2 versus 3/4: |
Rather (2) | 531 | 689 | 308 | 223 | ||
Rather not (3) | 134 | 111 | 68 | 66 | ||
Not at all (4) | 59 | 49 | 25 | 34 | ||
|
||||||
General health | ||||||
Very good (1) | 111 | 141 |
1/2 versus 3/4/5: |
63 | 48 |
1/2 versus 3/4/5: |
Good (2) | 360 | 421 | 217 | 143 | ||
Satisfactory (3) | 305 | 351 | 168 | 137 | ||
Less good (4) | 166 | 176 | 91 | 74 | ||
Bad (5) | 90 | 113 | 48 | 43 | ||
|
||||||
Health problems | ||||||
Sick the last 4 wks: no | 705 | 899 |
|
410 | 295 | n.s. |
Back pain: yes | 684 | 771 | n.s. | 390 | 293 | n.s. |
Circulation: yes | 433 | 486 | n.s. | 225 | 208 |
|
Gynacological: yes | 106/685 | 91/750 | n.s. | 61/388 | 44/297 | n.s. |
Urological: yes | 145 | 156 | n.s. | 82 | 63 | n.s. |
Gastrointestinal: yes | 330 | 377 | n.s. | 189 | 141 | n.s. |
|
||||||
Constipation characteristics | ||||||
Duration (years) | 9.7 ± 0.5 | 9.2 ± 0.5 | n.s. |
|
|
|
12 months’ prevalence | 614 | 762 |
|
352 | 262 | n.s. |
4 weeks’ prevalence | 422 | 441 |
|
237 | 185 | n.s. |
Acute constipation | 196 | 191 |
|
104 | 92 | n.s. |
To doctor | 240 | 200 |
|
131 | 109 | n.s. |
Medication | 353 | 345 |
|
194 | 159 | n.s. |
<3 stools/week | 380 | 398 |
|
199 | 181 |
|
Straining | 659 | 653 |
|
388 | 271 | n.s. |
Hard stools | 764 | 830 |
|
439 | 325 | n.s. |
+Number with secondary school finished (maturation);
As can be seen, the two steps (accepting the questionnaire to be sent and returning the questionnaire) generated two distinct self-selection biases in the sample: the first with respect to the severity of the constipation symptoms and the latter with respect to the age and health comorbidity conditions. Patients with more severe constipation symptoms, more acute problems, more medication intake and doctor visits because of constipation, and a higher burden by different constipation symptoms were more willing to provide further information and accepted the questionnaire to be sent.
After they had received the questionnaire, another self-selection bias is apparent: those that returned the questionnaire were on average 10 years older than those that did not respond, and this was associated with a higher percentage being retired, having lower overall life satisfaction, additional (circulation) problems, and a longer duration of constipation. However, second, this self-selection was not based on constipation symptom severity.
Table
IBS and constipation symptoms according to the Rome Modular Questionnaire (RMQ) (validated German version). Absolute number of respondents is given. Please note that the sequence of questions was different than in the RMQ because all participants were asked for their constipation symptoms first (52–58, 59), followed by the abdominal pain/discomfort questions (41, 45, 43, 46–50, and 44). Data are unweighted.
RMQ item | Question | Number of respondents ( |
||||||
---|---|---|---|---|---|---|---|---|
Frequency of symptoms |
0 | 1 | 2 | 3 | 4 | |||
52 | Less than 3 stools/week | 312 | 128 | 72 | 28 | 20 | ||
53 | Hard or lumpy stools | 107 | 262 | 117 | 59 | 7 | ||
54 | Straining for stools | 92 | 226 | 132 | 66 | 31 | ||
55 | Feeling of incomplete evacuation | 143 | 222 | 143 | 34 | 12 | ||
56 | Obstructed defecation | 257 | 193 | 77 | 23 | 7 | ||
57 | Digital manipulation needed | 321 | 161 | 41 | 12 | 6 | ||
58 | Problems to relax for evacuation | 226 | 233 | 59 | 20 | 9 | ||
46 | Pain improved w/defecation | 73 | 95 | 100 | 126 | 96 | ||
47 | Onset associated w/defecation | 264 | 126 | 35 | 39 | 12 | ||
48 | Less stools with pain/discomfort | 231 | 148 | 44 | 28 | 13 | ||
49 | Softer stool with pain/discomfort | 202 | 149 | 47 | 56 | 16 | ||
50 | Harder stools w/pain/discomfort | 165 | 172 | 86 | 53 | 13 | ||
44 | Pain/discomfort affecting daily life | 251 | 195 | 70 | 17 | 8 | ||
59 | Constipation starting > 6 months | No: 203 | Yes: 339 | |||||
Frequency# | 0 | 1 | 2 | 3 | 4 | 5 | 6 | |
41 | Abdominal pain/discomfort | 149 | 97 | 46 | 129 | 61 | 71 | 17 |
45 | Pain/discomfort for > 6 months | No: 238 | Yes: 301 | |||||
43 | Associated w/menstruation° | No: 211 | Yes: 37 |
All symptoms associated with IBS are present to an almost equal extent, and similarly all constipation symptoms are. Also, abdominal pain and discomfort was reported by 4/5, but only a small fraction (approx. 25%) experienced abdominal pain/discomfort at least once a week or more, thus matching the minimal requirement for IBS.
Among all 589 respondents, 9 women acknowledged being pregnant—they were excluded—leaving 580 data sets to be entered into this analysis.
When asked for concurrent GI and non-GI diagnoses, 245 persons reported one or more diagnoses to be present, and in 314 cases medication was taken at least twice per week, resulting in 366 cases of putative “comorbid constipation” (62.9%). The data of this subsample were excluded from this analysis but will be reported in a separate paper. The 214 remaining cases of “functional constipation” (38.1%) were included and are presented here.
Of all patients with assumed nonsomatic (“functional”) constipation (
Age and sex distribution were similar in all three groups (Table
Sociographic data and health problems and life satisfaction in functionally constipated participants (
Variable name | IBS-C, |
FC-R, |
FC, |
Statistics# | |||
---|---|---|---|---|---|---|---|
ANOVA or chi-square | Pairwise post hoc test | ||||||
1-2 | 1–3 | 2-3 | |||||
Personal data | |||||||
Age (mean, SD) | 44.1 ± 1.6 | 44.6 ± 2.9 | 43.2 ± 1.5 | n.s. | — | — | — |
Male : female | 17 : 47 | 12 : 24 | 41 : 73 | n.s. | — | — | — |
Height (m) | 1.70 ± 0.01 | 1.68 ± 0.02 | 1.70 ± 0.01 | n.s. | — | — | — |
Weight (kg) | 72.0 ± 2.2 | 65.9 ± 1.9 | 72.2 ± 1.5 | n.s. | — | — | — |
BMI | 24.7 ± 0.6 | 23.3 ± 0.5 | 24.8 ± 0.5 | n.s. | — | — | — |
|
|||||||
Social situation | |||||||
Education: secondary+ | 27 | 9 | 39 | n.s. | — | — | — |
Full-time/part time (1) | 31 | 25 | 56 |
1/2 versus 3/5 |
— | — | — |
Mini job, occasional (2) | 9 | 5 | 11 | ||||
Not working, training (3) | 13 | 3 | 12 | ||||
Parent time (4) | 3 | 0 | 9 | ||||
Retired (5) | 8 | 3 | 16 | ||||
Income: >2,500€/mo | 24 | 17 | 39 | n.s. | — | — | — |
|
|||||||
Life satisfaction | |||||||
Fully (1) | 15 | 14 | 40 |
1/2 versus 3/4: |
|
n.s. | n.s. |
Rather (2) | 36 | 21 | 59 | ||||
Rather not (3) | 7 | 1 | 15 | ||||
Not at all (4) | 6 | 0 | 0 | ||||
|
|||||||
General health | |||||||
Very good (1) | 13 | 6 | 30 |
1/2 versus 3/4/5: |
— | — | — |
Good (2) | 28 | 20 | 52 | ||||
Satisfactory (3) | 12 | 8 | 21 | ||||
Less good (4) | 8 | 3 | 9 | ||||
Bad (5) | 4 | 0 | 2 | ||||
|
|||||||
Health problems | |||||||
Sick the last 4 wks: no | 48 | 33 | 93 | n.s. | — | — | — |
Back pain: yes | 43 | 22 | 59 | n.s. | — | — | — |
Circulation: yes | 22 | 10 | 21 | n.s. | — |
|
— |
Gynacological: yes | 8/47 | 1/24 | 12/73 | n.s.+ | — | — | — |
Urological: yes | 1 | 4 | 8 | n.s.+ | — | — | — |
Gastrointestinal: yes | 29 | 9 | 22 |
|
n.s. |
|
n.s. |
#ANOVA: univariate, 3 groups, or 2 × 3 chi-square: in case of significance, pairwise post hoc comparisons; +number with secondary school finished (maturation);
When asked for their acute health problems, again no major differences occurred between the functional constipation subgroups except that significantly more gastrointestinal symptoms beyond constipation were reported in individuals with IBS-C as compared to FC.
As shown in Table
Clinical data and health care behaviors in the functionally constipated participants (
IBS-C, |
FC-R, |
FC, |
Statistic# | ||||
---|---|---|---|---|---|---|---|
ANOVA | Post hoc test | ||||||
1-2 | 1–3 | 2-3 | |||||
Constipation characteristics | |||||||
Duration of C (in years) | 9.1 ± 1.4 | 9.6 ± 2.4 | 8.6 ± 1.2 | n.s. | — | — | — |
To doctor for C: yes | 13 | 2 | 15 | n.s. | — | — | — |
Medication for C: yes | 21 | 6 | 23 | n.s. | — | — | — |
<3 stools/w: yes | 27 | 19 | 32 |
|
n.s. |
|
|
Straining: yes | 51 | 20 | 65 |
|
|
|
n.s. |
Hard stools: yes | 54 | 28 | 79 | n.s. | — | — | — |
|
|||||||
Health care behaviors | |||||||
Current medication: yes | 11 | 8 | 11 | n.s. | — | — | — |
Does it help |
11 | 8 | 11 | n.s. | — | — | — |
Side effects |
14 (11) | 5 | 11 | n.s. | — | — | — |
Changed diet: yes | 41 | 21 | 36 |
|
n.s. |
|
|
Sick leave for C: yes | 4 | 0 | 6 | n.s.+ | — | — | — |
Inpatient for C: yes | 0 | 0 | 2 | n.s.+ | — | — | — |
CAM for C: yes | 13 | 4 | 6 |
|
n.s. |
|
n.s. |
Currently working: yes | 43 | 28 | 78 | n.s. | — | — | — |
Yes: clean WC available |
37 | 25 | 65 | n.s.+ | — | — | — |
Yes: WC visit any time |
12 | 10 | 32 | n.s. | — | — | — |
C: constipation; CAM: complementary and alternative medicine; #ANOVA: univariate, 3 groups, or chi-square: “IBS” versus “functional constipation” (FC-R + FC): only in case of significance, pairwise post hoc comparisons;
Current medication intake for constipation was similar for IBS-C (17.2%), FC-R (22.2%), and FC (9.6%) (Table
Individuals with constipation had similar and lowered QoL on the SF-12 physical health domain in all three groups (IBS-C, FC-R, and FC) compared to population norms of the test, but in IBS-C the scores were also significantly lower in comparison to FC-R and FC, in both the physical health and the mental health domain (Figure
Quality-of-life in groups of constipated participants (individuals with IBS-C, FC-R, and FC, see text for definitions) as measured by the SF-12 (arbitrary units, mean ± SD) in the physical domain (a) and the mental domain (b).
Comparing the responses of individuals reporting to have been constipated in the past 12 months during a telephone interview [
This had also consequences for the remaining and assumed functionally constipated individuals, as it challenges to label these data as representative for Germany, as we did with the data from the telephone survey [
However, while we may have lost the representativity of our sample of functionally constipated individuals, we have no evidence indicating that the ratio between the three subgroups (IBS-C, FC-R, and FC) has changed; neither is the sex distribution nor the age or any other descriptor any different between them. Thus we can assume that, in Germany, more than half of individuals with functional constipation do not match Rome criteria, neither for IBC-C nor for functional constipation. Whether this holds also true for the other IBS-associated symptoms, specifically diarrhea and alternating bowel habits, cannot be answered with our data, as we did not include patients reporting diarrhea in our survey, neither during telephone interviewing nor with the questionnaire. Hence, we cannot conclude either whether the ratio between IBS-subtypes that has been reported from other countries [
Individuals with functional constipation (IBS-C, FC-R, and FC) appear to be similar with respect to most of the social and clinical descriptors assessed in our survey. For example, differential profile has not been observed before. The individual burden of constipation is well established [
One other characteristic of IBS-C patients is evident from our analysis of the telephone survey data (Table
Some more limitations of our data analysis need acknowledgement, beyond the self-selection biases discussed above. We also used rather liberal criteria to define “comorbid constipation” based on self-reported diagnoses and/or regular medication intake, the latter with a cut-off of 2 or more days per week. This may have inflated the number of individuals that were assembled in the group with “comorbid constipation” and downsized the number of patients with functional constipation for this analysis, since regular use of a PPI does not necessarily imply functional dyspepsia or gastric ulcer or GERD, and the frequent use of sleeping pills does not necessarily indicate a central or autonomic nervous system disturbance. In some cases, individuals reported intake of diabetic medication but not the diagnosis of diabetes, which my shed light on the comprehension of the questionnaire by some participants. Finally, the presence of a somatic disease does not necessarily indicate that constipation is caused by this disease; it may be incidental comorbidity, and the absence of a somatic condition in those labeled functional constipation does not confirm that a comorbid somatic condition does not exist; epidemiological data relying solely on subjective reports always carry the risk of false information. Therefore, some of the volunteers labeled “comorbid constipation” and excluded for this analysis may instead belong into one of the groups included in the present analysis, and such correction may diminish some of the found differences, although the opposite may happen as well.
Johannes Leinert, Menno Smid, and Thorsten Köhler are employees of
This research was supported by a grant from Shire-Movetis NV, Belgium, to Paul Enck at the University Hospital Tübingen. Paul Enck has served as consultant in an advisory board and as speaker for Shire Germany. The authors Johannes Leinert, Menno Smid, Thorsten Köhler, and Juliane Schwille-Kiuntke declare that there is no conflict of interests regarding the publication of this paper.
Paul Enck had the idea for the study, and Paul Enck and Juliane Schwille-Kiuntke designed the interview and questionnaire. Johannes Leinert, Menno Smid, and Thorsten Köhler contributed to interview and questionnaire design, supervised the data collection performed “in-house” at
This research was supported by a grant from Shire-Movetis NV, Belgium. The authors would like to thank Alain Joseph (Shire, Eysins, Switzerland) and Paul Hodgkins (Shire Development LLC, Wayne, Pennsylvania, USA) for their help during development of the questionnaire. They also acknowledge support by Deutsche Forschungsgemeinschaft and Open Access Publishing Fund of the University of Tübingen.