Naturopathic Approaches to Irritable Bowel Syndrome

Abstract

Introduction:

Irritable bowel syndrome (IBS) affects 11% of the population, and up to 50% of patients report using complementary and alternative medicines (CAM) for it. To date, there is no research describing how providers of naturopathic medicine in North America, a well-defined CAM profession, approach IBS.

Methods:

A Delphi study was conducted over a 17-month period in 4 rounds with 15 North American naturopathic medicine experts in IBS. Consensus was defined as a median value of 75% or greater agreement with the relevant statement.

Results:

Consensus was met with 45 statements describing a “reasonable naturopathic approach” to IBS. These statements covered the domains of general, office visits, tracking progress, testing, interventions, and resources.

Conclusion:

These results represent the beginning of an evidence base depicting naturopathic interventions for IBS and should inform future randomized controlled clinical trials in this area. Future research should look to reflect on and revise these guidance consensus statements particularly extending to other stakeholders as well as geographic and regulatory jurisdictions in the naturopathic profession.

Introduction

Irritable bowel syndrome (IBS) is a functional bowel disorder affecting 11% of the population globally.¹ IBS symptoms can include changes in stool consistency and frequency, have associated pain, and can range widely in severity.²

IBS patients are increasingly turning to complementary and alternative medicine (CAM) for management of their condition.^3,4 Research into CAM is an emerging field, with many of these therapies having low grade or what is deemed to be insufficient evidence to be accepted by conventionally trained providers.⁵ Despite this, patients self-report CAM therapies as useful for symptom relief, with more than 50% of IBS patients using CAM therapies as a component of their treatment.⁶

Naturopathy is a distinct CAM system of health care.⁷ Within this system, differences in practices and jurisdiction may occur, with a wide variation in training and scope of practice both nationally and internationally.⁷ North American (U.S. and Canadian) naturopathic doctors are trained to the same standards and curriculum, and in general have the widest scope of practice across naturopathy worldwide.^8,9 Naturopathic training supports the use of diet, dietary supplements, herbal preparations, behavioral interventions, and pharmaceuticals for the treatment of IBS.¹⁰ However, there have been no studies of whole-system naturopathic medicine for IBS, and there are currently no guidelines regarding practice patterns of naturopathic doctors for IBS in North America.

The aim of this Delphi study was to develop a list of consensus statements that would constitute a “reasonable naturopathic approach” to IBS as practiced in North America, in consultation with naturopathic IBS experts in the United States and Canada. This study is reported in accordance with reporting guidelines for Delphi surveys.^11,12

Materials and Methods

Design

This study was designed and conducted by using a Delphi technique, with reference to previous Delphi studies in the CAM field.^13,14 This iterative survey method is frequently used in health research, allowing purposive sampling of recognized experts in the field of interest, across geographically diverse locations.^11,15 The Delphi technique enables consensus building via iterative survey presentation, while providing anonymity and equality of participant views.¹¹

The design, conduct, and analysis of the Delphi survey was overseen by a four-member international steering committee (J.Z.G., L.W., A.D., K.C.). The members were chosen for their combined representation of naturopathy, Delphi methodology, and geographical diversity. Before the initial round of the survey, the committee met via Skype meetings to develop the survey protocol, and establish eligibility criteria, a priori consensus cutoffs, and termination criteria.

Ethical approval for the study was sought from the Bastyr University Institutional Review Board (IRB) (#16-1554) and found to be exempt from full IRB review as it met the exemption criteria listed under 45 CFR 46.101(b)(4), thus providing assurance that the investigators as well as the study design and conduct met minimum requirements for the ethical conduct of research in human participants.

Panelist selection and recruitment

To ensure the Delphi outcomes would be relevant to the scope of practice of North American naturopaths, expert panelists were defined as naturopathic professors, clinicians, or researchers from the United States or Canada who focused on the treatment of IBS. Using a purposive sampling method, the steering committee, familiar with the North American naturopathic gastroenterology community, built an initial list of potential panelists that was based on individuals identifying as being experienced with naturopathic approaches to IBS. This list was then augmented with subsequent snowball sampling, whereby potential panelists referred or recommended additional panelists. All recruitment was conducted via email invitation using a standardized script for inviting participants.

Procedure

The Delphi survey was conducted over a 17-month period from March 2016 to July 2017. Each survey consisted of items grouped under one of six possible domains: (1) general (e.g., items relating to general attitudes toward diet in IBS treatment); (2) office visits (e.g., duration and frequency of consultations); (3) tracking progress (e.g., the use of symptoms trackers); (4) testing (e.g., laboratory tests, serology tests); (5) interventions (e.g., dietary, supplement); and (6) resources (e.g., written materials, smart phone applications). In addition, a free-text question was included in each domain, for panelists to comment on the current survey items (i.e., relating to relevance or clarity of the question), and suggest new questions for the domain.

As per the iterative Delphi procedure, each round of the survey was analyzed when completed, with the results forming the content of the subsequent round. Each round took ∼20 min to complete. Panelists were given 2 weeks to complete each round, with nonresponders sent two reminder emails. Iterative rounds of the survey were conducted until termination criteria were met, as follows: All items either reached consensus for inclusion or exclusion or maintained a stable rating of nonconsensus for two consecutive rounds.

A list of potential items for the round 1 survey was initially drafted by the steering committee members with expertise in the research and clinical care of naturopathy for IBS in North America (J.Z.G., K.C., A.D.). Participants were asked to respond to the items by using a visual analogue Likert scale of agreement from 0% to 100% on the importance of the item in making up a reasonable naturopathic approach to IBS.

Individual items from the round 1 survey were analyzed according to a priori consensus criteria, and either automatically included in the final Delphi list, excluded from the survey, or forwarded to round 2 for re-rating. In addition, several items were re-worded for clarity, and forwarded for rating, together with any new items suggested by panelists. Subsequent rounds followed this procedure, until the Delphi survey reached termination criteria at the completion of round 4.

Analysis and consensus

Individual items were analyzed for central tendency (median), variance (inter-quartile range [IQR]), and percentage of each rating of agreement (from 0 to 100). A priori consensus for automatic inclusion of an item was defined as a median score of ≥75%, and for automatic exclusion of an item it was defined as a median score <40%.^13,14

Items whose median scores ranged between 40% and 74% (nonconsensus items) were forwarded to the subsequent round. Nonconsensus items for which both the median and the IQR remained stable within this 40%–74% range, indicating no further movement toward consensus for inclusion or exclusion, were deemed as showing inter-round stability for nonconsensus, and excluded from further rounds.¹⁴

Results

Recruitment

Twenty-two potential panelists were identified through the recruitment process and invited to participate; of these, 15 (68%) consented to participate in the Delphi survey. Of the remaining seven, five did not respond to the invitation, one declined to participate because of time constraints, and one declined to participate because they did not focus on gastroenterology with sufficient self-identified expertise. Of the 15 panelists, 53% were male, two thirds practiced in the United States (66%), and all were practicing clinicians (Table 1).

Table 1.

Panelist Demographics

Demographic	N (%)
Gender
Male	8 (53)
Female	7 (47)
Nationality
The United States	10 (67)
Canada	5 (33)
Practicing clinicians	15 (100)
Academic/research	6 (40)

Delphi rounds

All 15 participants completed the round 1 survey (100% response rate). The statements and questions covered all six domains of general, office visits, tracking progress, testing, interventions, and resources. Of the six agreement statements, two reached consensus for inclusion (Table 2), one reached consensus for exclusion (Table 3), and three were forwarded to round 2 for re-rating. In addition to the 3 forwarded Delphi statements, 258 free-text answers from 26 open-ended questions were formatted into 50 items suitable for rating on an agreement scale from 0%–100%, as per the round 1 items. In total, 53 items were forwarded to the next round, grouped into the 6 domains as per round 1.

Table 2.

45-Item Delphi Recommendation of “Reasonable” Naturopathic Approaches for Irritable Bowel Syndrome in North America

Domain	Item	Round: median score
General	“Dietary interventions are an important part of naturopathic approaches to IBS.”	Round 1: Median 99
Office visits	“Granting that certain patient situations may require flexibility…”
	3 Months is a reasonable minimum period of time needed for an IBS patient to achieve adequate relief using naturopathic approaches.	Round 3: Median 83
	3 Visits are a reasonable minimum number of visits needed for an IBS patient to achieve adequate relief using naturopathic approaches.	Round 3: Median 81
	A reasonable IBS treatment frequency might be to see the patient every 2–4 weeks initially and then monthly, extending to every 2–3 months later if needed.	Round 2: Median 87
	A reasonable visit length for a patient with IBS might be 60 min for the initial visit and 30 min for follow-up visits.	Round 2: Median 79
Tracking progress	“Granting that certain patient situations may require flexibility, a reasonable naturopathic IBS approach uses…”
	Patient-reported symptom relief to check for improvement	Round 2: Median 99.5
	Patient diet diaries and symptom trackers	Round 4: Median 77
Testing	“Granting that certain patient situations may require flexibility, reasonable naturopathic IBS testing might include using…”
	Laboratory-based testing, specifically IgG, SIBO, and CDSA testing	Round 2: Median 83.5
	IgG-based food sensitivity tests	Round 4: Median 77
	SIBO (i.e., lactulose breath testing for methane and hydrogen)	Round3: Median 93
	Stool analysis (e.g., CDSA) results should inform dietary choices in IBS	Round 1: 76
Interventions	“Granting that certain patient situations may require flexibility, a reasonable naturopathic IBS intervention might include using…”
Diet	Low FODMAPs diet	Round 2: Median 77
	Therapeutic diets and/or dietary recommendations based on the elimination diet and/or IgG testing results.	Round 2: Median 85.5
	Reducing wheat/gluten	Round 2: Median 81
	Eating hygiene (chewing food thoroughly, eating mindfully, etc.)	Round 2: Median 87
	A regular meal pattern (frequency and timing of food consumption)	Round 3: Median 79
Products	Supplements	Round 2: Median 87.5
	Probiotics	Round 2: Median 90
	Digestive enzymes	Round 2: Median 77
	Bitters	Round 2: Median 81
	Carminatives	Round 3: Median 82
	Tea	Round 3: Median 85.5
	Tincture	Round 3: Median 76
Mind–body	Mental stress reduction	Round 2: Median 83.5
	Exercise	Round 2: Median 77
	Meditation	Round 3: Median 75.5
	Acupuncture	Round 3: Median 75
	Yoga	Round 4: Median 77
Elimination diets	“For those of you who do use elimination diets please consider in your mind a reasonable naturopathic elimination diet for IBS and grade the importance of avoiding the following foods…”
	Gluten/wheat	Round 2: Median 99
	Dairy	Round 2: Median 98.5
	Sugar	Round 2: Median 98.5
	Processed food	Round 2: Median 98
	Deep fried food	Round 2: Median 99.5
	Fast food	Round 2: Median 100
	FODMAPs	Round 2: Median 75
	Lactose	Round 2: Median 84
	Soy	Round 2: Median 79
	Soda	Round 2: Median 99
	Artificial sweeteners	Round 2: Median 97
	Fructose	Round 3: Median 75
	Fructans	Round 3: Median 76.5
	Polyols	Round 4: Median 84
	Corn	Round 4: Median 78
Resources	“Granting that certain patient situations may require flexibility, a reasonable naturopathic IBS intervention might include…”
	Utilizing handouts	Round 2: Median 98
	Recommending books	Round 2: Median 85

IBS, irritable bowel syndrome.

Table 3.

Excluded Items

Domain	Item	Round: median score
Office visits	“Granting that certain patient situations may require flexibility…”
	1 Month is a reasonable minimum period needed for an IBS patient to achieve adequate relief using naturopathic approaches.	Round 3: Median 24
	1 Visit is a reasonable minimum number of visits needed for an IBS patient to achieve adequate relief using naturopathic approaches.	Round 3: Median 8
	2 Visits are a reasonable minimum number of visits needed for an IBS patient to achieve adequate relief using naturopathic approaches.	Round 3: Median 25
Testing	“Nonlaboratory based testing (e.g., muscle energy testing) should inform dietary choices in IBS.”	Round 1: Median 17
	“Granting that certain patient situations may require flexibility, a reasonable naturopathic IBS intervention might include using the following laboratory tests:”
	ALCAT-based food sensitivity tests	Round 3: Median 21
	Blood type	Round 3: Median 33
	None	Round 4: Median 26
Elimination diet	For those of you who do use elimination diets, please consider in your mind a “reasonable naturopathic elimination diet for IBS” and grade the importance of avoiding the following foods:
Elimination diet	Shellfish	Round 2: Median 22

IBS, irritable bowel syndrome.

All 15 panelists completed the round 2 survey (100% response rate). Of the 53 survey items, 27 reached consensus for inclusion (Table 2), 1 reached consensus for exclusion (Table 3), and 25 were forwarded to the next round for re-rating. In addition to the 25 forwarded Delphi statements, 8 statements were added by the steering committee to clarify previous round answers, and 18 previous survey questions were re-formatted into agreement format (0%–100% rating scale) for the following round. A total of 51 items were forwarded for the next round.

All 15 panelists completed the round 3 survey (100% response rate). Of the 51 survey items, 11 reached consensus for inclusion (Table 2), 5 reached consensus for exclusion (Table 3), and 7 statements had inter-round stability of median and IQR scores, and therefore were also removed from subsequent rounds. The remaining 28 statements, with median scores between 40% and 74% (nonconsensus items), were forwarded to round 4. No new items were generated from free-text comments, resulting in a total of 28 items in the round 4 survey.

Fourteen panelists completed the fourth round of the survey (93% response rate). Of the 28 survey items, 5 reached consensus for inclusion (Table 2), and 1 reached consensus for exclusion (Table 3). The remaining 22 items had inter-round stability of nonconsensus median and IQR from round 3 to round 4. As such, termination criteria were achieved for these remaining items, and the survey was completed.

Discussion

Fifteen expert panelists competed a four-round Delphi survey to establish core naturopathic treatments for IBS in North America. Consensus was reached on the inclusion of 45 items (Table 2), comprising the domains of (1) general (1 statement), (2) office visits (4 statements), (3) tracking progress (2 statements), (4) testing (4 statements), (5) interventions (32 statements), and (6) resources (2 statements). Items in the largest domain, interventions, are further grouped into four subdomains of (5a) diet (5 statements), (5b) products (7 statements), (5c) mind–body (5 statements), and (5d) elimination diet (15 statements). As discussed next, some of these items reflect current practice and knowledge, whereas others are less commonly practiced in the conventional gastroenterology community, or have a weaker evidence base.

The experts in our panel were unanimous in their agreement of dietary interventions as an important naturopathic approach to IBS. This contrasts markedly with a conventional medical approach, where the role of diet in IBS has traditionally been somewhat ignored,¹⁶ although, more recently, this may be changing.¹⁷

For the survey items related to office visits, panelists considered a minimum of three visits over a 3-month period, with a 60-min initial visit and 30-min follow-ups, as reasonable to reach adequate relief of IBS symptoms using naturopathic interventions. These parameters are in line with a recent international survey of naturopathic practitioners, where more than 80% of respondents noted that initial naturopathic visits were 60 min in length and 50% of respondents noted that follow-ups ranged from 30 to 45 min.⁷ The suggestion that a 3-month minimum would be needed to see adequate relief is particularly useful in planning future clinical trial protocols, as current FDA recommendations suggest the selection of a 2-month minimum intervention period for IBS clinical trials,¹⁸ which may be too short for naturopathic studies. In addition, the use of diet dairies and symptom trackers would be an important inclusion in clinical studies, and it would support the FDA's recent guidance for patient reported outcomes in IBS trials.¹⁸

When considering testing, the Delphi list includes the use of IgG-based food sensitivity testing, hydrogen/methane breath testing, and comprehensive stool analysis, which includes measurements on microbiota for example. Although there is some evidence supporting the use of diets directed by IgG food sensitivity results in IBS patients,¹⁹ it is not common practice within conventional gastroenterology, potentially due to concerns regarding diagnostic accuracy.²⁰ The use of breath testing in IBS patients is quite controversial in conventional gastroenterology, with trials both supporting²¹ and refuting²² its utility. Many naturopathic doctors will utilize comprehensive stool tests that are commonly available from functional laboratories, and our expert panel agreed with the utility of such packaged tests. These test packages often include numerous individual tests depicting markers of digestion, metabolism, and microbiology, ranging from elastase to fecal calprotectin and to quantification of commensal and pathogenic organisms. Some of these tests are more established in their clinical utility in IBS,²³ whereas others, such microbiota evaluation, are still emerging fields.

Also of note is the strong agreement that more esoteric testing methods such as muscle energy testing and blood type-based therapeutics should be excluded. Also excluded was the utility of leukocyte activation testing (i.e., ALCAT). Interestingly, although there were no randomized controlled trials on this testing method concurrent to the 17 months of the Delphi study, a high-quality randomized controlled trial published subsequent to the Delphi completion suggested a clinically significant benefit from diets based on leukocyte activation testing in IBS patients.²⁴

Thirty-two of the Delphi recommendations relate to interventions including diet, products, mind–body, and elimination diet. Some of the included diet recommendations have preliminary research evidence support but remain controversial, such as the utility of low FODMAP diets and other elimination diets including avoidance of gluten in nonceliac patients.²⁵ Other consensus statements are shared with those in conventional medicine such as eating hygiene (chewing food thoroughly), eating mindfully, and following a regular meal pattern (frequency and timing of food).²⁶

Evidence is mixed for the effectiveness of products such as supplements, teas, and tinctures, or interventions such as probiotics, bitters, and carminatives for the treatment of IBS, all of which were included in the consensus statements. Meta-analyses of probiotics for the treatment of IBS suggest benefit.^27,28 Likewise, although the evidence base supporting the use of digestive enzymes in IBS is sparse, there is some indication that it may be helpful in this population.²⁹ Herbal bitters are traditionally used in herbal medicine to stimulate gastrointestinal motility and are often used in constipation predominant IBS populations by naturopathic doctors¹⁰ but have minimal clinical trial support to date.³⁰ Traditionally, carminative herbs such as peppermint oil are used by naturopathic doctors in treating IBS^10,31 and a Cochrane review of nine randomized controlled trials suggest that peppermint oil is safe and effective in IBS patients.³²

Five mind–body disciplines/interventions have been included as treatment approaches for IBS: mental stress reduction, meditation, exercise, acupuncture, and yoga. Conventional gastroenterology under the leadership of the Rome Foundation has emphasized the brain–gut connection as an important element in IBS³³ and there is a growing evidence base supporting the use of stress reduction, meditation, and other mind–body approaches to IBS.³⁴ Other interventions that reached consensus have growing evidence bases as well, including exercise,³⁵ acupuncture,³⁶ and yoga.³⁷

Elimination diets (followed by reintroduction trials) are commonly used by naturopathic doctors for IBS as well as other conditions.^10,31 There are varied forms of elimination diets and they can vary extensively in which foods are permitted and which are avoided. Within our panel we identified a number of food items that reached consensus on avoidance. There was near-complete agreement, with medians ranging from 97 to 100 on the need to eliminate gluten/wheat, dairy, sugar, processed food, deep fried food, fast food, soda, and artificial sweeteners. Soy and corn avoidance as well as avoiding FODMAPs (fermentable oligo-, di-, monosaccharides, and polyols) reached consensus, although with medians in the 70s for the most part. Although generally not recommended for widespread use, elimination diets of varying forms, particularly with FODMAP avoidance, are gaining traction in conventional medicine.²⁵

Finally, the inclusion of educating patients through provision of handouts in the naturopathic management of IBS is again a consideration for inclusion in both clinical practice and future clinical trials. Despite this recommendation, there is a dearth of evidence depicting or prescribing the content or effectiveness of patient-focused educational handouts provided by naturopathic doctors. Although this has been explored in the context of patient–provider relationships in other medical approaches to patients with IBS,³⁸ this represents an area for future research for the naturopathic profession.

This study has some limitations. First, the sample size of 15 expert panelists is relatively low. However, this is reflective of the small population of North American naturopathic doctors, from which we purposively further targeted experts in IBS. It is possible that despite our best efforts, purposive and snowball sampling may have introduced a selection bias in our panel of experts. This choice of recruitment was a pragmatic decision, as there is currently no registry of naturopathic doctors who focus on gastroenterology in general or IBS in particular. Second, the Delphi recommendations are based on a North American focus of practice. Considering the wide range of teaching, tradition, and scope of naturopathy worldwide,⁷ we chose to limit heterogeneity in our sample and focus on North American naturopathic medicine exclusively. Third, our sample was made up of naturopathic IBS experts, even though, as an extremely prevalent disorder, IBS is often treated in general practice. It is possible that our experts in naturopathic IBS approaches may be sought after by patients with more recalcitrant disease. However, to address some of these limitations, we have recently launched an international research consortium of naturopathic teaching clinics³⁹ to investigate the practice patterns of general practice naturopathic medicine in the teaching clinics of the United States, Canada, Australia, and New Zealand, and published a protocol for a prospective observational study that has been informed by these Delphi recommendations.⁴⁰ It will be interesting to compare and contrast these patterns with the findings of this North American Delphi panel. Finally, as naturopathic medicine is regulated differently across states and provinces, this may have influenced panelist ratings, particularly as it relates to issues of scope of practice such as pharmaceutical prescriptions or requisition of laboratory tests.

Conclusion

This study aimed at identifying areas of consensus among naturopathic experts in IBS. Panelists reached consensus on a 45-item list of reasonable naturopathic approaches for IBS in North America. Consensus was reached in the domains of general approaches to IBS, office visits, tracking progress, testing, interventions, and resources. It is our intention that these results will inform protocol development in future randomized controlled trials. We believe that there is opportunity for future refinement of these consensus guidelines, reflecting an evolving field of evidence-informed practice of naturopathic medicine.

Footnotes

Acknowledgments

The authors would like to thank all 15 experts on their Delphi panel who graciously gave of their time to help build the evidence base for naturopathic approaches to IBS. They are also grateful to Dr. Masa Sasagawa, ND for early review of their protocol, and to Dr. Paul Amieux, PhD for his unwavering support of naturopathic research at Bastyr University.

Author Disclosure Statement

No competing financial interests exist.

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