Systematic review: the efficacy of treatments for irritable bowel syndrome--a European perspective

The serotonin reuptake inhibitor citalopram does not affect colonic sensitivity or compliance in rats

Altered serotonin signaling has been implicated in the pathophysiology of irritable bowel syndrome (IBS). Selective serotonin reuptake inhibitors (SSRI) improve IBS symptoms, although the mechanism of action remains unclear. We assessed the effects of the SSRI, citalopram, on colonic sensitivity and compliance in rats after acute and repeated administration. Colorectal distension was performed in conscious rats. Pressure-volume relationships during colorectal distension (2-20 mmHg), fitted using a power exponential model [Vol=V(max)xexp[-(kappaxRelP)(beta)], were used as a measure of colonic compliance. The visceral pain-related visceromotor response during colorectal distension (10-80 mmHg) was used to assess visceral sensitivity. Pressure-volume curves and visceromotor responses were assessed after acute citalopram (3 or 10 mg/kg, ip) or vehicle and after repeated treatment (7 and 14 days; 3 or 10 mg/kg/day). In vehicle-treated animals, pressure-volume curves were similar over time. Citalopram (acute or repeated treatment) did not affect neither the pressure-volume curves nor the visceromotor response to colorectal distension. Thus, citalopram, after acute or repeated administration, had no significant effects on colon compliance or visceral pain during colorectal distension in rats. These results agree with recent observations in humans suggesting that the therapeutic actions of citalopram in IBS are independent of any effects on colonic sensorimotor function.

Effect of a fermented milk containing Bifidobacterium animalis DN-173 010 on the health-related quality of life and symptoms in irritable bowel syndrome in adults in primary care: a multicentre, randomized, double-blind, controlled trial

BACKGROUND

Health-related quality of life (HRQoL) has been rarely evaluated as a primary endpoint in the assessment of the effect of probiotics on the irritable bowel syndrome (IBS).

AIM

To study the effects of fermented milk containing Bifidobacterium animalis DN-173 010 and yoghurt strains on the IBS in a multicentre, double-blind, controlled trial.

METHODS

A total of 274 primary care adults with constipation-predominant IBS (Rome II) were randomized to consume for 6 weeks either the test fermented milk or a heat-treated yoghurt (control). HRQoL and digestive symptoms were assessed after 3 and 6 weeks on an intention-to-treat population of 267 subjects.

RESULTS

The HRQoL discomfort score, the primary endpoint, improved (P < 0.001) in both groups at weeks 3 and 6. The responder rate for the HRQoL discomfort score was higher (65.2 vs. 47.7%, P < 0.005), as was the decrease in bloating score [0.56 +/- (s.d.)1.01 vs. 0.31 +/- 0.87, P = 0.03], at week 3 in the test vs. the control group. In those subjects with <3 stools/week, stool frequency increased (P < 0.001) over 6 weeks in the test vs. control group.

CONCLUSIONS

This study suggests a beneficial effect of a probiotic food on discomfort HRQoL score and bloating in constipation-predominant IBS, and on stool frequency in subjects with <3 stools/week.

Irritable bowel syndrome

Irritable bowel syndrome (IBS) is a disease of unclear, complex pathophysiology characterised by abdominal pain and discomfort and altered bowel activity. It affects an estimated 10-15% of individuals worldwide and has a large impact on quality of life (QOL) and both direct and indirect healthcare costs. Symptoms of IBS are usually triggered by disruption of gastrointestinal (GI) function secondary to infection, dietary factors, lifestyle changes or psychological stress. While most currently available pharmacological treatments of IBS focus on symptomatic treatment of the syndrome, agents that attempt to address the pathophysiology of the disease, in particular the role of serotonin, have received much attention in recent years. However, there is growing concern that serotonergic agents as a class may be associated with rare, but serious, episodes of ischaemic colitis, with several cases of this complication having been reported in association with use of serotonergic agents that have reached the market. Thus, there remains an important need for safe and effective agents that treat the symptoms of IBS. Otilonium bromide, a spasmolytic agent, has been widely used worldwide and has been found to be effective and safe for managing abdominal pain. Clinical trials indicate that it improves baseline abdominal pain and distension, and is particularly effective in reducing diarrhoea. Combining otilonium bromide with benzodiazepines, such as diazepam, may improve the efficacy of the agent with respect to GI symptoms, while also treating underlying anxiety disorders. More research is required to confirm the efficacy and mechanisms of action associated with this combination therapy in IBS. Safety data from clinical trials and postmarketing sources indicate that otilonium bromide is well tolerated, with a safety profile comparable to placebo in clinical trials and only two reported cases of adverse reactions (urticaria) among 10-year postmarketing data. This article reviews the pathophysiology and treatment of IBS with a particular focus on the role of otilonium bromide in the management of this condition.

Body awareness therapy: A new strategy for relief of symptoms in irritable bowel syndrome patients

AIM: To compare irritable bowel syndrome (IBS) patients with apparently healthy persons and to evaluate body awareness therapy, which is a physiotherapeutic remedy focusing on normalising tensions in the body, for the treatment of IBS with the hypothesis that altered body tension is associated with the syndrome.

METHODS: Twenty-one IBS patients received body awareness therapy two hours weekly for 24 wk. At baseline as well as after 12 and 24 wk, they underwent examinations including resource oriented body examination in combination with body awareness scale evaluation and filled in gastrointestinal and psychological symptom questionnaires. Saliva cortisol was analysed. A group of 21 apparently healthy persons underwent the same examinations once.

RESULTS: Compared to the apparently healthy group, IBS patients scored higher at baseline for gastrointestinal and psychological symptoms. They showed more often alterations in normal body tension patterns, as well as deviating cortisol slopes in saliva. After 24 wk of body awareness therapy, their gastrointestinal and psychological symptoms were reduced overall. Somatic symptoms decreased in parallel with depressive symptoms. Whole body pain score decreased, coping ability as well as biochemical stress markers improved.

CONCLUSION: IBS patients scored higher for gastrointestinal and psychological symptoms, and presented with altered biochemical stress markers. Their body tension deviated compared to healthy controls. Furthermore, body awareness therapy gave relief of both somatic complaints, psychological symptoms and normalised body tension. These findings indicate that distorted tension constitutes an important part of the symptoms in IBS.

[Novel therapeutic approaches in the treatment of irritable bowel syndrome]

The treatment of irritable bowel syndrome due to the heterogeneous clinical symptoms and coexisting psychiatric disorders is still controversial. Although several agents with different mechanisms of action are widely used in clinical practice, there are only few drugs available with strong evidence of their efficacy, safety and tolerability at present. The etiology of irritable bowel syndrome is considered to be multifactorial: experimental and clinical research on visceral hypersensitivity, motility and brain-gut axis involving its neurotransmitters and receptors created the foundation of novel therapeutic approaches. Albeit nowadays several drugs (alosetron, tegaserod) have been registered in a few countries for the treatment of irritable bowel syndrome, further large clinical trials are required related to the new chemical entities.

Acute exacerbation of pain in irritable bowel syndrome: efficacy of phloroglucinol/trimethylphloroglucinol. A randomized, double-blind, placebo-controlled study

BACKGROUND

Abdominal pain is the predominant symptom in irritable bowel syndrome patients. Phloroglucinol and its methylated derivative are antispasmodic agents acting on smooth muscle.

AIM

To evaluate the efficacy of phloroglucinol/trimethylphloroglucinol on pain intensity during an acute exacerbation of pain of irritable bowel syndrome over a 1-week period treatment.

METHODS

Irritable bowel syndrome Rome II patients seeking medical advice for an acute exacerbation of abdominal pain were randomized to phloroglucinol/trimethylphloroglucinol (62.2 mg P + 80 mg TMP) two pills three times daily or placebo for 7 days. Patients were included if they had a pain with a minimal intensity of 40 on a 100-mm visual analogue scale, and if pain occurred at least 2 days during the week previous inclusion.

RESULTS

Three hundred and seven patients were included by 78 general practitioners. The intent-to-treat population included 300 patients, aged of 46.9 +/- 14.8 years (73% female). The relative decrease of pain intensity at day 7 was 57.8 +/- 31.7% vs. 46.3 +/- 34.7% (Delta = 11.5 +/- 3.8%, [CI(95%): 4.0 ; 19.1], P = 0.0029) and the percentage of patients with at least a 50% decrease of pain intensity was 62% vs. 47% (Delta = 15.3 +/- 5.7%, [CI(95%): 4.1 ; 26.5], P = 0.0078) in phloroglucinol/trimethylphloroglucinol and placebo groups, respectively.

CONCLUSIONS

A 1-week phloroglucinol/trimethylphloroglucinol treatment significantly reduces pain intensity in irritable bowel syndrome patients consulting their general practitioners for pain exacerbation.