Follow-up of patients with functional bowel symptoms treated with a low FODMAP diet
Maagaard L, Ankerson DV, Vegh Z et al.
World Journal of Gastroenterology. 2016, 22(15):4009-4019
IBS symptoms are prevalent in about 10-20% of the general population, with a high proportion of undiagnosed sufferers, making IBS a major health issue. Furthermore, IBS-like symptoms are commonly found in patients with inflammatory bowel disease (IBD) and have been shown to be present in 30-40% of patients in clinical remission.
World Journal of Gastroenterology. 2016, 22(15):4009-4019
IBS symptoms are prevalent in about 10-20% of the general population, with a high proportion of undiagnosed sufferers, making IBS a major health issue. Furthermore, IBS-like symptoms are commonly found in patients with inflammatory bowel disease (IBD) and have been shown to be present in 30-40% of patients in clinical remission.
A low FODMAP diet (LFD) has been shown to be an effective treatment for functional gastrointestinal symptoms and is increasingly used as a tool in the management of IBS. In addition, it seems to reduce functional symptoms in patients with IBD. Adherence to treatment is key, with upto 75% of patients expected to adhere. However, implementation of the diet into daily life can be difficult due to the complexity of the diet.
This retrospective, cross-sectional study aimed to investigate patient-reported long-term effects of the LFD, long-term adherence and dietary impact on disease course in patients with IBS and patients with IBD and co-existing IBS treated with the LFD.
Consecutive patients with IBS or IBD and co-existing IBS, having received LFD education followed by a dietary course of varying duration, were invited to participate in the study. All patients had been referred for IBS dietary management with clinical dietitians. Prior to dietary consultation, patients were assessed and underwent various investigations including a colonoscopy, with the majority of patients presenting with normal results, as well as tests for lactose intolerance and coeliac disease. Patients were excluded if significant gastrointestinal co-morbidities were present such as abdominal cancer or ileo-/colostomy. Patients were required to remain on the LFD for 6-8 weeks and then review response to treatment with support from a dietitian. If this was considered satisfactory, patients moved to the reintroduction phase of the diet to determine individual tolerance levels and ensure dietary variety. Patients were either offered follow-up via clinic or telephone, however, were also able to email their dietitian. At follow-up, patients were asked to undertake seven questionnaires. Four self-developed questionnaires were used to assess adherence to the diet, efficacy of and satisfaction with treatment as well as asking patients to identify their disease course before and after dietary management using the Copenhagen IBS Disease Courses. In addition, the following internationally validated questionnaires were used: i) Bristol stool chart; ii) IBS severity scoring system (IBS-SSS); iii) IBS Quality of Life (IBS-QOL) and iv) Short IBD questionnaire (SIBDQ).
A total of 403 (294 IBS, 109 IBD) patients were identified as eligible to participate in the study, However, 15 were excluded due to co-morbidities, migration or uncertain IBS diagnosis and 40 rejected the invitation. Of the remaining 348 patients, a total of 180 patients responded to one or more of the questionnaires (131 IBS, 49 IBD) and were included. 20 patients did not consent to extraction of data from their medical records and so only data from the questionnaires was available for this group. The IBS-D subtype was more frequent in the IBD group and the IBS-C subtype in the IBS group. The proportion of IBD patients with mild IBS at follow-up was significantly greater when compared with IBS patients. The median duration of follow-up from initial dietary consultation to questionnaire completion was 16 months.
The study found that 150 patients (86%) reported either partial or full effectiveness of dietary treatment with a greater number of the IBD group reporting full effectiveness when compared with the IBS group. The LFD appeared to show the greatest effect on bloating and abdominal pain. 37% of the IBS group and 24% of the IBD group reported becoming asymptomatic whilst following the diet.
Following treatment with the LFD, the proportion of patients reporting a chronic continuous disease course was significantly reduced in both groups, with the mild indolent course becoming the predominant course type. This was associated with a good QOL and normal stool pattern. Those patients reporting one of the three less favourable disease courses at the start had a 40% probability of moving to the mild indolent course. Following dietary intervention, the proportion of patients reporting a normal stool pattern increased (41% in IBS group, 66% in IBD group).
Approximately a third of both groups were assessed as adherent to the diet from the questionnaires. 32% of the IBS group and 37% of the IBD group followed the LFD for < 3 months, whilst 47% and 50% respectively remained on the diet until follow-up. Just over 50% used the diet intermittently depending on symptom severity, whilst the rest followed the diet continuously. 84% followed a modified LFD where some high FODMAP foods were reintroduced to individual tolerance levels, with the remaining patients strictly adhering to treatment. Wheat, dairy and onions were the foods most often not reintroduced by patients. 26% of the IBS group and 20% of the IBD group reported abandoning the diet before completing the standard dietary treatment period for a number of reasons including: i) too complicated to follow (50%); ii) too expensive (23%); iii) bland in taste (15%) with other reasons (53%) including co-morbidities and detrimental effect on gastrointestinal symptoms. Satisfaction with dietary management was reported in 83 (70%) of the IBS group and 24 (55%) of the IBD group. Good QOL was associated with normal stool type following dietary intervention and duration of dietary course.
This study is the first to examine the impact of a LFD on long-term IBS disease course. The results suggest those with more severe chronic courses might be able to improve this with management on a LFD. Further prospective studies are required to support this finding. There are limitations to this study such as the high rate of patients (48%) not replying to the invitation which might have led to selection bias, in addition to possible recall bias. However, whilst there are limitations, the study supported use of the LFD in both IBS patients and IBD patients with co-existing IBS. The majority of patients reported beneficial effects and satisfaction with treatment. Furthermore, long-term disease courses and stool pattern were significantly improved. Long-term prospective studies are required to further investigate characteristics of responders to the LFD, the impact of diet on IBS disease course and safety of long-term dietary restriction of FODMAPs.
Read original study
This retrospective, cross-sectional study aimed to investigate patient-reported long-term effects of the LFD, long-term adherence and dietary impact on disease course in patients with IBS and patients with IBD and co-existing IBS treated with the LFD.
Consecutive patients with IBS or IBD and co-existing IBS, having received LFD education followed by a dietary course of varying duration, were invited to participate in the study. All patients had been referred for IBS dietary management with clinical dietitians. Prior to dietary consultation, patients were assessed and underwent various investigations including a colonoscopy, with the majority of patients presenting with normal results, as well as tests for lactose intolerance and coeliac disease. Patients were excluded if significant gastrointestinal co-morbidities were present such as abdominal cancer or ileo-/colostomy. Patients were required to remain on the LFD for 6-8 weeks and then review response to treatment with support from a dietitian. If this was considered satisfactory, patients moved to the reintroduction phase of the diet to determine individual tolerance levels and ensure dietary variety. Patients were either offered follow-up via clinic or telephone, however, were also able to email their dietitian. At follow-up, patients were asked to undertake seven questionnaires. Four self-developed questionnaires were used to assess adherence to the diet, efficacy of and satisfaction with treatment as well as asking patients to identify their disease course before and after dietary management using the Copenhagen IBS Disease Courses. In addition, the following internationally validated questionnaires were used: i) Bristol stool chart; ii) IBS severity scoring system (IBS-SSS); iii) IBS Quality of Life (IBS-QOL) and iv) Short IBD questionnaire (SIBDQ).
A total of 403 (294 IBS, 109 IBD) patients were identified as eligible to participate in the study, However, 15 were excluded due to co-morbidities, migration or uncertain IBS diagnosis and 40 rejected the invitation. Of the remaining 348 patients, a total of 180 patients responded to one or more of the questionnaires (131 IBS, 49 IBD) and were included. 20 patients did not consent to extraction of data from their medical records and so only data from the questionnaires was available for this group. The IBS-D subtype was more frequent in the IBD group and the IBS-C subtype in the IBS group. The proportion of IBD patients with mild IBS at follow-up was significantly greater when compared with IBS patients. The median duration of follow-up from initial dietary consultation to questionnaire completion was 16 months.
The study found that 150 patients (86%) reported either partial or full effectiveness of dietary treatment with a greater number of the IBD group reporting full effectiveness when compared with the IBS group. The LFD appeared to show the greatest effect on bloating and abdominal pain. 37% of the IBS group and 24% of the IBD group reported becoming asymptomatic whilst following the diet.
Following treatment with the LFD, the proportion of patients reporting a chronic continuous disease course was significantly reduced in both groups, with the mild indolent course becoming the predominant course type. This was associated with a good QOL and normal stool pattern. Those patients reporting one of the three less favourable disease courses at the start had a 40% probability of moving to the mild indolent course. Following dietary intervention, the proportion of patients reporting a normal stool pattern increased (41% in IBS group, 66% in IBD group).
Approximately a third of both groups were assessed as adherent to the diet from the questionnaires. 32% of the IBS group and 37% of the IBD group followed the LFD for < 3 months, whilst 47% and 50% respectively remained on the diet until follow-up. Just over 50% used the diet intermittently depending on symptom severity, whilst the rest followed the diet continuously. 84% followed a modified LFD where some high FODMAP foods were reintroduced to individual tolerance levels, with the remaining patients strictly adhering to treatment. Wheat, dairy and onions were the foods most often not reintroduced by patients. 26% of the IBS group and 20% of the IBD group reported abandoning the diet before completing the standard dietary treatment period for a number of reasons including: i) too complicated to follow (50%); ii) too expensive (23%); iii) bland in taste (15%) with other reasons (53%) including co-morbidities and detrimental effect on gastrointestinal symptoms. Satisfaction with dietary management was reported in 83 (70%) of the IBS group and 24 (55%) of the IBD group. Good QOL was associated with normal stool type following dietary intervention and duration of dietary course.
This study is the first to examine the impact of a LFD on long-term IBS disease course. The results suggest those with more severe chronic courses might be able to improve this with management on a LFD. Further prospective studies are required to support this finding. There are limitations to this study such as the high rate of patients (48%) not replying to the invitation which might have led to selection bias, in addition to possible recall bias. However, whilst there are limitations, the study supported use of the LFD in both IBS patients and IBD patients with co-existing IBS. The majority of patients reported beneficial effects and satisfaction with treatment. Furthermore, long-term disease courses and stool pattern were significantly improved. Long-term prospective studies are required to further investigate characteristics of responders to the LFD, the impact of diet on IBS disease course and safety of long-term dietary restriction of FODMAPs.
Read original study
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