乌鸦传媒

Women with concurrent irritable bowel syndrome (IBS) and endometriosis experience significant improvement in bowel symptoms with a low FODMAP (fermentable oligosaccharides, disaccharides, monosaccharides and polyols) diet, a recent study suggests.¹

Endometriosis affects approximately 10% of women of reproductive age and is associated with menorrhagia, severe dysmenorrhea, abdominal pain, and often, bowel symptoms similar to those seen in IBS, resulting in many patients being treated for IBS prior to a diagnosis of endometriosis.^2,3 Despite the difficulty distinguishing these conditions, not many studies have investigated the association between IBS and endometriosis.

The low FODMAP diet decreases the amount of ingested FODMAPs, or poorly absorbed, small molecules that are readily fermentable by bacteria, and as a result, leads to decreased pain and bloating in patients with visceral hypersensitivity.⁴ Visceral hypersensitivity is a hallmark of IBS and is also reported in women with endometriosis, suggesting a potential therapeutic option in these patients.⁵

A recent study published in the Australian and New Zealand Journal of Obstetrics and Gynaecology by Judith S. Moore, a PhD Candidate from Monash University and Alfred Hospital, Melbourne, Victoria, Australia, and colleagues, sought to evaluate symptom patterns and response to a low FODMAP diet in women with IBS and known endometriosis or in women with IBS and without endometriosis.

鈥淚 was working as a functional gut nurse specialist in the private sector and noticed a high number of referrals by gynecologists for help with their endometriosis patients who had IBS symptoms,鈥� Moore said. 鈥淢any patients reported being told they had IBS for a number of years before finally having endometriosis diagnosed, so I became very interested in a possible link between the two,鈥� she explained.

Patients and methods

This study evaluated 231 consecutive female patients referred to a private IBS clinic over a 5-year period who returned for follow-up. Patients completed structured symptom questionnaires and an assessment and examination by a nurse specialist. Patients with endometriosis were diagnosed prospectively or retrospectively via laparoscopy by a consultant gynecologist.

Patients with a confirmed diagnosis of IBS by Rome III criteria received education and resources about the low FODMAP diet, including the Monash University Low FODMAP Diet digital application for iPhone and Android and the low FODMAP diet booklet.

Endometriosis prevalence and characteristics

Of the included patients, 44 did not meet Rome III criteria for IBS, leaving 160 women with a confirmed IBS diagnosis. Of these women with IBS, 37% reported a history or recent diagnosis of endometriosis, whereas 63% had no known endometriosis diagnosis.

Patients with IBS were significantly younger than patients who did not meet the Rome III criteria (37 vs 48 years). A significantly higher proportion of patients with IBS also had endometriosis compared with patients who did not have an IBS diagnosis (37% vs 15%).

Age, nulliparity, and a family history of endometriosis were significantly associated with concurrent endometriosis. Women with endometriosis were more likely to have undergone a hysterectomy and were significantly more likely to report pain in the pelvis and back, dyspareunia, and bowel symptoms affected by menstruation compared with women who did not have endometriosis. Women without endometriosis more frequently reported predominant diarrhea compared with women with endometriosis (20% vs 6%).

鈥淚 was surprised with the finding of the low FODMAP diet working better in women with endometriosis as I thought all patients with symptoms of bloating and abdominal pain would respond equally,鈥� Moore said.

Improved symptoms with the low FODMAP diet

All patients exhibited high adherence to the diet, with over 90% adherence from patients with IBS and endometriosis and in patients with IBS only. Of all women with IBS, 58% reported an improvement in symptoms of greater than 50%. Significantly more women with known endometriosis reported symptom improvement compared with women with IBS alone (72% vs 49%), which represented a 3-fold increased chance of responding to the low FODMAP diet in women with endometriosis compared to women without endometriosis.

Moore has further research questions stemming from these results. 鈥淚 am wondering if there is generally a higher rate of endometriosis in women with IBS, is it being missed? Are the women with IBS alone the group of patients that tends to not respond to therapies in general?鈥� she asked.

Conclusions

In this study, Moore and colleagues demonstrated specific symptoms, including pelvic pain, a family history of endometriosis, and dyspareunia, that may lead to earlier treatment and reduce complications from endometriosis. The low FODMAP diet effectively reduced bowel symptoms in women with endometriosis, suggesting that endometriosis may be predictive of improved chances of response to the low FODMAP diet.

鈥淭his was a retrospective analysis, so it is limited by a number of factors as discussed in the paper,鈥� explained Moore. Laparoscopy to exclude endometriosis was not performed in all patients; therefore, the control group may not be a true negative control. This study was carried out in a single center and the generalizability of the results is unknown. Symptom data collection was carried out with a non-validated tool, but the tool was adapted from previously validated questionnaires.

鈥淎 prospective clinical trial is needed and being planned,鈥� said Moore. 鈥淎necdotally, a number of dietitians are using the low FODMAP diet for women with endometriosis where there is a growing awareness among some gynecologists that this can contribute to symptom relief for some of their patients,鈥� she continued.聽

Overall, these results demonstrate that endometriosis is common in women with IBS. The authors report symptoms and historical clues associated with endometriosis that should facilitate the diagnosis and treatment of endometriosis. Finally, the presence of endometriosis may be predictive of increased chances for responding to the low FODMAP diet, likely due to the association with visceral hypersensitivity.

鈥淐linicians should be aware of specific symptoms in women with IBS symptoms and consider whether endometriosis should be considered as a concurrent diagnosis,鈥� said Moore. 鈥淭hose clinicians looking after women with endometriosis and bowel symptoms should consider referring to a dietitian with low FODMAP experience as another treatment option,鈥� she continued.

Published: June 09, 2017