Constipation is a common gastrointestinal condition characterised by infrequent defecation, difficulty in passing stools or both. It can occur for a multitude of reasons, with geographical, linguistic, cultural and educational differences influencing its definition (Barberio et al, 2021). These discrepancies can make the evaluation and standardisation of prevalence data from cross-sectional surveys difficult.
The Rome Foundation coined the term ‘functional constipation’ to help standardise the diagnosis of persistent constipation in the absence of a physiological problem. Over the past two decades, the Rome criteria have been increasingly used in cross-sectional research to assess the prevalence of functional constipation worldwide (Simren et al, 2017). Such uniformity is crucial, given that assessing the incidence of constipation using alternative or informal criteria can result in a 40% difference in prevalence estimates (Werth et al, 2019).
Functional constipation (FC), also known as idiopathic constipation, accounts for approximately 95% of constipation cases in the adult population (Vriesman et al, 2020). It is defined as the simultaneous presence of two or more signs for at least 3 months, including straining in more than one in four defecations; lumpy or hard stools in more than one in four defecations; a sensation of incomplete evacuation in more than one in four defecations; a sensation of anorectal obstruction/blockage in more than one in four defecations; and using manual manoeuvres to facilitate more than one in four defecations (eg digital evacuation and pelvic floor support); and/or fewer than three defecations per week.
FC has a prevalence in the range of 3–27% in the general population (Serra et al, 2020). This burdensome condition has an impact on quality of life, with consequences such as a continuous sense of incomplete evacuation and the need to manually empty the rectum (Daniali et al, 2020) and haemorrhoids (Sandler et al, 2019). Depending on the criteria used (such as Rome I–IV) (Simren et al, 2017), FC affects between 1 in 6 and 1 in 10 people worldwide.
International guidelines recommend treatment with osmotic laxatives (Serra et al, 2020) although other methods have been studied in the literature, such as acupuncture (Liu et al, 2016), dietary supplementation with probiotics (Ibarra et al, 2018), biofeedback (Norton et al, 2017), abdominal massage, manual lymphatic drainage and electrical stimulation (Drouin et al, 2020). Most authors agree on the usefulness of bowel re-education and pelvic floor rehabilitation in constipated patients, as pointed out in a recent review of guidelines (Bassotti et al, 2021) and by the NHS website (2020). This suggests the need for special attention by health professionals working in pelvic clinics, among others, as these practitioners are likely to be the first to be contacted by people seeking help to address constipation.
Laxatives can lead to dependence and abuse, with irritation of the large intestine. Laxative abuse is common in several population groups such as older people and those with eating disorders (Bashir and Sizar, 2021). A case of renal failure and electrolyte alteration from laxative abuse has been reported in the literature (Bokhari et al, 2018) although there is general consensus about the safety of these products (Rao and Brenner, 2021). Paradoxically, laxative abuse makes evacuation difficult over time because the bowel requires progressively higher doses and stronger stimuli to activate peristalsis. This makes non-pharmacological management important for patients, along with proper nutritional advice and bowel retraining.
Indications in the literature on non-pharmacological (conservative) management include education and lifestyle adjustments, such as dietary recommendations, regular physical activity and advice on posture when using the toilet (Vriesman et al, 2020). Rehabilitation nurses play a key role in conservative management because of their training in patient education and rehabilitation of pelvic conditions.
Although numerous articles emphasise the importance of these interventions, few authors have provided a comprehensive description of them. Therefore, it would be useful to study and describe the effects of an evidence-based programme for relieving FC.
Aim
To describe the results of an evidence-based, nurse-led educational intervention for functional constipation in adults.
Methods
First, a retrospective study was conducted in the nurse-led pelvic rehabilitation and stoma care outpatient clinic at a major hospital in Milan, northern Italy. This was done by examining the records of all patients of both sexes since the clinic was set up who were presenting for chronic constipation as defined by international guidelines (Serra et al, 2017).
All patients had been screened by a physician and were following the recommendations provided by the above-mentioned guidelines. Nutritional and bowel elimination habits were assessed according to the criteria published in a previous work on a different condition related to the pelvic floor (Terzoni et al, 2021). In summary, these criteria include: monitoring fluid intake and quantity; characteristics of food regarding type of fibre (whether soluble or insoluble); evacuation habits and posture; and stool characteristics. Patients were referred to a specialist in nutrition in case of known or suspected food intolerance, dysbiosis or improper diet. The Wexner constipation score (Agachan et al, 1996) and Bristol stool charts (Lewis and Heaton, 1997) were used to assess patients at baseline, after 4 weeks and after the end of the intervention.
Table 1 gives the details of the intervention, which is based on recent evidence regarding evacuation posture (Heitmann et al, 2021), relaxation in case of urgency to evacuate (Deb et al, 2021) and dietary advice (Bardsley, 2017; Forootan et al, 2018; Thompson, 2020; Fathallah et al, 2021).
Table 1. The educational programme
| Intervention | Description |
|---|---|
| Evacuation posture | Sit with legs apart and feet firmly placed on a stool (approximately 20 cm high—the knees should be higher than the hips) and lean slightly forward |
| RelaxationTo be performed when the person feels the urge to evacuate | Sit with legs apart and feet firmly placed on a stool (about 20 cm, your knees should be higher than your pelvis), place your elbows on your knees and lower your chin towards your chest. Try to arch your back outwards. Exhale all the air and hold breath as long as possible while keeping your eyes closed. Then take two normal breaths and repeat the apnoea. Repeat three times before evacuating |
| Diet | On waking, drink a glass of water (at room temperature) and wait at least 5–10 minutes before eating breakfast
|
Regarding nutritional education, particular attention was paid to fibre. The advice reported in Table 1 is based on the fact that coarse insoluble fibre (eg wheat bran) mechanically irritates the mucosa of the large intestine, promoting water and mucus secretion. On the contrary, soluble fibre (eg psyllium) holds water and resists dehydration, thus increasing the overall volume of the stools (McRorie et al, 2017).
The intervention was considered complete when evacuation occurred daily without manual compression of the abdomen, took less than 5 minutes and produced a sensation of complete evacuation, with stools scoring 4 on the Bristol scale (Serra et al, 2020).
Continuous variables were described as mean and standard deviation if normally distributed, or median and quartiles otherwise (the Shapiro-Wilk test was used to assess normality of data distribution). Baseline data were compared using the Student's t-test for independent samples (Mann-Whitney's U was used in cases of skewed distribution). Repeated measures analysis of covariance were used to study the differences in Bristol and Wexner scores over time, considering BMI and age as covariates. Goodness of fit was assessed by calculation of the R-squared coefficient; analysis of residuals was performed and partial eta-square with a 95% confidence interval was calculated to quantify the effect size. Mauchly's test was used to assess sphericity and Greenhouse-Geisser's correction was applied after such test. The significance threshold was set at 5% for all calculations; data were analysed using SAS version 9.
The study complied with the rules of standard hospital good practice and approved by the institutional board as part of a larger research project. The principles in the Declaration of Helsinki and the national law on data protection were fully respected.
Patients were enrolled consecutively. All patients provided their informed consent and could withdraw from the study at any time.
Results
Twenty-nine patients were enrolled, 19 women and 10 men, with a median age of 61 years (IQR=53–71; skewed distribution, Shapiro-Wilk P=0.04) and a mean BMI of 24.4±3.88 kg/m2; there were no significant differences between men and women (P=0.06 and P=0.39 respectively for age and BMI).
Baseline characteristics were comparable between men and women in terms of Wexner scores (P=0.25) and Bristol stool score (P=0.30). Overall, the median Wexner scores indicated moderate constipation according to the authors of the scale, whereas the Bristol stool scores were close to the worst possible situation (completely dry stools). Table 2 reports the scores at the beginning of the study, after 4 weeks and after the intervention. Data are presented as median and interquartile range (1st–3rd quartile).
Table 2. Scores obtained during the intervention
| Score | Baseline | 4 weeks | After rehabilitation | P value |
|---|---|---|---|---|
| Wexner | 10 (8–12) | 4 (2–6) | 2 (0–2) | <0.001 |
| Bristol stool chart | 2 (2–3) | 3 (3–4) | 4 (4–4) | 0.682 |
A statistically significant improvement was obtained in Wexner constipation scores, with good effect size (partial eta-squared 0.26) and a clinically relevant decrease in the scores over time (Figure 1).
The Bristol scores did not show any statistically significant difference. However, from a practical point of view, the characteristics of the stools changed from ‘lumpy’ to ‘normal’, which indicates a clinically relevant improvement. The improvements in both Bristol and Wexner scores were independent of BMI, age and sex (Table 3).
Table 3. P values related to age, BMI and sex
| Score | Age | BMI | Sex |
|---|---|---|---|
| Wexner | 0.49 | 0.38 | 0.11 |
| Bristol stool chart | 0.60 | 0.32 | 0.14 |
These findings suggest that this programme might be of help to both women and men, considering that age and BMI were not significantly different between the sexes and the programme had similar results in women and men.
Conclusions
Although small in size, this preliminary investigation showed the intervention had promising results, suggesting that such an evidence-based, nurse-led intervention can be useful for treating functional constipation in adults after proper medical assessment, in the framework of a multidisciplinary team (such as in a pelvic unit).
This last consideration is particularly important. Given the complexity and the number of factors to be considered during assessment and rehabilitation, the patient reporting constipation often needs to go through several steps of consultations and therapies before an adequate solution is found. Laxatives, although generally safe, can lead to dependence and abuse, with irritation of the large intestine and the paradoxical effect of constipation.
In the authors' experience, it is sometimes difficult to believe how poor the knowledge of essential nutritional and evacuative principles is among patients in all age groups; the need for this essential information and education is confirmed by the presence of large-scale projects on food education in recent international literature (Downer et al, 2020). Simple lifestyle interventions have long been known to help address constipation (Vriesman et al, 2020) but no studies had reported the complete details of a full intervention.
To the authors' knowledge, this is the first paper in this field to provide precise indications regarding diet, posture and habit retraining (details in Table 1). Some similar information can be found in reference textbooks (Chen et al, 2022; Diaz et al, 2022) but no scientific data regarding the efficacy of a complete programme of interventions have been published so far.
The next step of this study is to incorporate this educational programne into all consultations of patients presenting to the nurse-led clinic for any type of problem that could potentially influence bowel activity; this would include not only intestinal problems but also postsurgical consultations in cases of urological surgery that could influence bowel activity, such as radical prostatectomy (Kirschner-Hermanns et al, 2011).
Further investigation is needed on larger samples with a control group to confirm these results and to possibly further improve the intervention proposed in this paper.
KEY POINTS
- Constipation is a common gastrointestinal condition
- Despite numerous articles emphasising the importance of conservative interventions, no studies have described complete educational programmes
- A nurse-led intervention can have benefit for patients with constipation
- Evacuation posture, dietary intake (especially fibre) and relaxation exercises during evacuation are fundamental topics that should be discussed with patients.
CPD reflective questions
- Why does the incidence of functional constipation differ between countries, as reported in literature?
- What could motivate adults to use simple interventions such as education, given they can master the fundamental principles of nutrition and bowel function?
- Which factors related to lifestyle contribute the most to constipation among those in the geographic area where you work?