IBS

Question 1

Describe IBS in terms of:
- definition
- subtypes
- aetiology
- prevalence

Answer 1

IBS (irritable bowel syndrome) is a chronic, relapsing lifelong gastrointestinal disorder.
Not one specific disease process, rather a collection of GI symptoms.

Subtypes:
IBS-D (watery stool >25%)
IBS-C (hard stool > 25%)
IBS-M (mixed hard/watery stools)
IBS-U (unrelated to bowel function)

Aetiology:
- dysfunction of the gut-brain axis
- genetics
- psychological and physiological stress
- dysbiosis of gut microbiome
- visceral hypersensitivity
- gut motility
- diet & lifestyle

Prevalence:
- 10-20% UK population have IBS
- any age affected
- more common in women

Question 2

How is IBS assessed and diagnosed?

Rome VI criteria
NICE criteria

Answer 2

Rome IV (2016) criteria:
Recurrent abdo pain avg 1 day/week in last 3 months with 2 or more of the following:
1. Pain (related to defecation)
2. Change in frequency of stool
3. Change in form of stool

NICE guidelines:
A - abdo pain
B - bloating
C - change in bowel habit (diarrhoea, constipation, frequency, consistency)

Blood tests:
- FBC
- ESR and CRP
- Antibody (rule out coeliac disease)

‘Symptom profile’ used during assessment to track frequency & severity of symptoms.

Question 3

What are the red flag symptoms of IBS?

Answer 3

• Blood in stool/rectal bleeding
• Unexplained weight l0ss
• Family hx cancer (colorectal/ovarian)
• Persistent change in bowel habit

Question 4

What is the pharmacological treatment for IBS?

Answer 4

• Antispasmodic (buscopan)
• Peppermint oil (gas/bloating)
• Laxative (aim type 4 stool) senna (stimulant), Movicol, fybogel (adds bulk)
• Antimotility agent (diarrhoea) e.g. Loperamide
• Antidepressant e.g., amitriptyline

If taking meds helps people manage symptoms and improves QoL they should be encouraged to continue taking.

Question 5

What are the methods of dietary assessment for IBS?

What are some key considerations?

Answer 5

• Detailed food diary/diet history
• Start food/symptom diary
• Previous dietary modifications

Key considerations:
- Common irritants: high fat food, greasy foopd, spice, fizzy, caffeine, alcohol
- Meal timing
- Fluid intake
- Fibre intake (overall amount, spread, type)
- Fruit & veg intake limit to 3/day
- Artificial sweetener (Esp those ending in -ol)

Question 6

What is the general dietary advice for IBS?

Answer 6

(NICE 2008)
- Have regular meals (avoid missing meals & long gaps between eating)
- Eat slowly
- Reduce intake of caffeine, fizzy drinks, alcohol
- Reduce resistant starch
- Reduce F&V intake to 3x portions per day

If symptoms persist it would be appropriate to try:
- single food avoidance
- exclusion diet

Question 7

What is the advice regarding fibre intake for IBS?

Answer 7

Altering dietary fibre (usually lowering) is the mainstay of dietary management of IBS.
–> increasing fibre intake in this group of patients would be inappropriate since it could worsen symptoms.

REDUCE:
- Short-chain soluble and highly fermentable dietary fibre, such as oligosaccharides.
- Result in rapid gas production that can cause abdominal pain/discomfort, abdominal bloating/distension and flatulence in patients with IBS.

INCREASE:
- Long-chain, intermediate viscous, soluble, and moderately fermentable dietary fiber (e.g., linseed, chia, psyllium).
- Can improve the overall symptoms of patients with IBS.
- Supplementation with this type of dietary fibre should be recommended to patients with all of the IBS subtypes.

IBS-C
- Linseeds evidenced to ease symptoms

Question 8

Describe the low FODMAP diet in the management of IBS.

What are the benefits and limitations of low FODMAP diet?

Answer 8

Short chain fermentable carbohydrates –> poorly absorbed = fermentation and osmotic changes in the bowel.
IBS gut hypersensitivity = symptoms

Can be up to 70% effective
should only be used as 2nd line approach as difficult & restrictive
HOWEVER
Doesn’t have to be all or nothing – can do a ‘soft’ fodmap to test the waters.

F -
- fermentable
- don’t fully digest/absorb so ferment in large bowel

O
- oligosaccharides
- Fructans (wheat, veg, onions)
- Galacto-oligosaccharides (pulses, beans, legumes)

D
- disaccharides
Lactose – milk/yoghurt

M
- monosaccharides
- fructose is poorly absorbed by some people

AP
- and polyols
- sorbitol, mannitol and xylitol (natural in fruit but also artificial sweeteners)

Phase 1
– restrict fodmaps for 4-8 weeks
Phase 2
– reintroduce fodmaps
If symptoms improve, reintroduce gently with individual fodmaps in isolation
Explores possible triggers in what quantity and frequency
Phase 3
– personalised low fodmap diet that can be flexible as required.

BENEFITS:

• All studies on low FODMAP diet have consistently shown symptomatic benefits in the majority of patients with IBS.

Up to 86% of patients with IBS find improvement in overall gastrointestinal symptoms as well as individual symptoms
Many people with IBS are able to reintroduce FODMAPs and control symptoms (avoids unnecessary food restrictions and helps to ensure that the patient consumes a nutritious, varied diet).

LIMITATIONS:

• Adherence by the patients and clear dietary intervention led by dietitians is vital for success.

Risks of inadequate nutrient intake and potential adverse effects from altered gut microbiota.

Question 9

Describe the role of pre/pro/synbiotics in the management of IBS

Answer 9

Mixed evidence

safe but ?effective
some research shows probiotics can provide symptom relief.
Recommended to take for minimum 3/4 weeks to see benefit.

Question 10

Describe the role of alternative therapies in treatment of IBS

Answer 10

IBS stongly linked to physiological and psychological stress:

• Relaxation therapy
• CBT
• Hypnotherapy
• Apps e.g., calm, nerva, headspace
• Yoga can be as effective as low FODMAP diet
• Gut directed acupuncture

Other treatments:
- Toilet position
- Bowel massage (ILU)
- Toilet plan