Gastro-oesophageal reflux disease

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Chapter 4 Gastro-oesophageal reflux disease

AETIOLOGY

Gastro-oesophageal reflux disease (GORD) is commonly encountered in clinical practice. Recent research has estimated the prevalence at 10–20% in Western nations.1 GORD has been defined as ‘a condition which develops when the reflux of stomach contents causes troublesome symptoms and/or complications’.2 Signs and symptoms of GORD result primarily from the recurrent reflux of gastric contents into the oesophagus (Figure 4.1). The pathogenesis of GORD is complex and multifactorial with a number of mechanisms appearing to be involved (Figure 4.2):

poor oesophageal acid clearance. Patients with GORD have been found to have less oesophageal peristaltic activity. This results in a reduced capacity to clear reflux contents from the oesophagus.5 Contact between the refluxed gastric contents and the oesophageal mucosa results in inflammation. This inflammation has been found to further reduce oesophageal peristalsis, further impairing acid clearance, and causing a worsening of reflux symptoms—a vicious circle.6
slow gastric emptying. Delayed gastric emptying (particularly of the proximal stomach) has been correlated with increased severity and frequency of reflux episodes in GORD patients.7 Delayed gastric emptying of ingesta has been postulated to contribute to GORD symptoms via two mechanisms: (1) by increasing the length of time refluxate is available in the stomach; and (2) increasing gastric distension, which has been found to increase the rate of transient LOS relaxations.8
hiatal hernia. Hiatal hernias have been found to be relatively common in patients suffering from GORD.10 They appear to promote LOS incompetence via a decrease in LOS resting pressure,11,12 and their presence is associated with increased severity of reflux.13
oxidative stress. Research has shown that mucosal damage in oesophagitis is mediated, at least in part, by oxygen-derived free radicals.14 Animal research has also found considerable levels of oxidative stress in the oesophageal mucosa after reflux episodes. This research also noted a significant mucosa protective effect from antioxidant supplementation.15

RISK FACTORS

A number of risk factors that appear to contribute to the initiation and maintenance of GORD symptoms have been identified. These usually involve lifestyle factors, although genetic influences and medications can also contribute to the disorder:

dietary factors. Dietary factors capable of precipitating reflux episodes include coffee and other caffeinated beverages, alcoholic beverages, chocolate, meals high in fat, and, potentially, peppermint essential oil (for example, peppermint candy).18 These substances are capable of increasing acid secretion (alcohol, coffee), reducing LOS pressure (alcohol, chocolate, coffee, fatty meals), causing transient LOS relaxations (alcohol, peppermint essential oil), slowing gastric emptying (alcohol, fatty foods) and/or impairing oesophageal motility (alcohol). Agents that can trigger pain by irritating an already inflamed oesophageal mucosa include tomato and citrus juice, soft drinks and spicy foods. From a naturopathic perspective, eating meals too quickly, consuming too large meals, consuming fluids with meals, eating close to bedtime and chewing food inadequately are other potential contributing factors to GORD.
smoking. Tobacco smokers report higher rates of reflux symptoms than non-smokers do.20 This is thought to be caused by smoking-induced decreases in resting LOS pressure. Coughing or even deep inhalation can cause acute increases in intraabdominal pressure capable of overpowering their feeble LOS.21

CONVENTIONAL TREATMENT

Conventional treatment aims to reduce the symptoms of GORD and reduce oesophageal damage through the use of antisecretory therapies, such as proton pump inhibitors or histamine type 2 receptor antagonists (H2RAs). Although these agents have been found to be effective in reducing the oesophageal symptoms of GORD and, to a lesser extent, extraoesophageal symptoms,26 their use is also associated with significant side effects and risks. Common adverse events of antisecretory therapies include diarrhoea, nausea, abdominal pain and headaches.27 Longer-term use of anti-secretory drugs is associated with increased risk of gastroenteritis,28 pneumonia,29 spinal fracture30 and vitamin and mineral malabsorption.31,32 More recently, the surgical procedure laparoscopic fundoplication has been advocated in the treatment of GORD.

KEY TREATMENT PROTOCOLS

The naturopathic protocols adopted to treat GORD usually focus on dietary and lifestyle modifications, in addition to botanical treatments. After relieving symptoms, the aim is to initially identify any factors that contribute to GORD and remove these triggers. If inflammation, ulceration or poor motility/sphincter tone is present, herbal or nutritional prescription may be of benefit.

Relieve symptoms

Relief of heartburn is paramount in the management of GORD. Gastrointestinal demulcents are typically very effective in providing prompt relief of heartburn symptoms (usually within minutes of ingestion). Effective demulcents include Althaea officinalis radix, Ulmus fulva cortex and Glycyrrhiza glabra.44 Gastrointestinal demulcents are most effective when administered in powdered form—mixed into a little water or apple juice to form a slurry or gruel. Tablets and capsules will be significantly less effective. Demulcents can be used ‘on demand’ or taken after meals and/or before bed for a preventative effect.

Eliminate exacerbating factors

Dietary factors

The naturopathic axiom tolle causum (‘treat the cause’) is particularly relevant to the management of GORD. While herbal demulcents can relieve heartburn symptoms effectively and promptly, their use, in some respects, is only palliative if patients continue to indulge in dietary factors known to exacerbate their condition. Avoidance of foods and drinks known to precipitate reflux episodes (for example, chocolate, alcoholic beverages, caffeinated beverages and fatty foods) is an important therapeutic strategy that may produce excellent clinical outcomes (see Chapter 5 on food intolerance/allergy),33 although it should be noted that an ‘evidence-based review’ of dietary changes was inconclusive due to insufficient research.18 The authors did, however, note that there is a definitive link in some sufferers of GORD with food and alcohol, as physiological evidence has demonstrated decreased LOS tone.

Other recommendations, such as taking time when eating, consuming smaller meals and avoiding fluid consumption with meals (both should decrease gastric distension) and chewing food adequately, are traditional naturopathic recommendations.34 Chewing food as thoroughly as possible is a traditional recommendation which may result in improved salivary gland function over time and, hence, improved oesophageal acid clearance. Changing the evening meal time to earlier in the evening (at least 3–4 hours before bedtime) can also be helpful.35

In infants and toddlers with GORD, a dairy-free diet should be implemented. If they are formula-fed, the mother should be encouraged to relactate. The use of an extensively hydrolysed whey formula is the next best option. Soy and goat’s milk formulas should be avoided as they share a significant amount of cross-reactivity with cow milk proteins. There have also been a number of studies demonstrating the efficacy of carob bean powder (Ceratonia siliqua) as a formula additive.36,37 Carob powder has been found to significantly decrease the severity and frequency of vomiting in infants with GORD, as well as increasing weight gain.36 If the infant is exclusively breastfed, then the mother should be placed on a dairy-free diet, as small, but clinically significant, amounts of dairy proteins do appear in the breast milk.

Lifestyle factors

In addition to the dietary factors discussed above, lifestyle factors such as obesity and smoking should be addressed. Weight loss has been shown in some research to result in reduced reflux episodes and should be encouraged in all overweight and obese patients.38 Cessation of smoking could be recommended for a number of compelling reasons, not the least of which is its effect on oesophageal reflux. Short-term studies (of 24–48 hours duration) have not consistently found a reduction in reflux episodes after smoking cessation.39,40 However, no longer-term studies have yet been performed and, in light of smoking’s well-known adverse effects, GORD patients who smoke should be encouraged to give up. Herbal thymoleptics, anxiolytics and adaptogens could play an important supportive role in this process (see the section on the nervous system).

Raising the head of the bed is another easy-to-implement lifestyle intervention that has demonstrated beneficial effects in GORD.18 This recommendation is based on the theory that acidic stomach contents will be more likely to reflux when patients are lying flat. Research has, thus far, mostly supported this theory, with intervention trials finding reduced frequency of reflux episodes, shorter reflux episodes and fewer reflux symptoms when bed heads were raised (one trial raised the head by 28 cm).41

Decrease oesophageal inflammation and promote oesophageal healing

The reduction of oesophageal inflammation and the promotion of oesophageal healing will help reduce the vicious circle of GORD. As previously discussed, inflammation is a common occurrence in GORD. Demulcents (as discussed above), anti-inflammatory and vulnerary herbs may soothe the tissue and enhance healing. Useful anti-inflammatory phytomedicines for the digestive system include Filipendula ulmaria, Glycyrrhiza glabra and Matricaria recutita, while vulnerary herbal medicines traditionally used to help heal the upper gastrointestinal tract include Althaea officinalis, Ulmus fulva, Calendula officinalis, Symphytum officinale and Aloe barbadensis.42,43 Given that alcohol is a common reflux exacerbating factor, teas are probably the preferred method of administration.

Given the role of free radicals in reflux-induced oesophageal inflammation,14 the promotion of antioxidant defences is a worthwhile, but as yet under-researched, therapeutic approach. The incorporation of brightly coloured fruits, vegetables, legumes and whole grains into the diet should be encouraged (see the food nutrient chart in Appendix 4).

Tone the lower oesophageal sphincter

A traditional naturopathic focus of treating GORD is to improve the tone of the smooth muscle of the LOS, thereby enhancing its capacity to hold gastrointestinal contents in the stomach. Poor LOS tone may be potentially improved by the use of tannin-rich herbs, which provide astringency and increased tissue tone, in addition to reducing inflammation.44 Hydrolysable tannin constituents (higher molecule weight tannins) primarily affect astringency.44 Botanicals that contain these tannins include Geranium maculatum, Achillea millefolium, Calendula officinalis, Hamamelis virginiana and Agrimonia eupatorium.45 The naturopath should be aware that long-term use or high doses of tannins may impede digestion. A prudent approach is to co-prescribe a herbal medicine with a bitter principle to stimulant digestion and to provide an adjuvant anti-inflammatory effect. However, to complicate matters, the use of bitters should be monitored carefully as this may worsen some people’s GORD.46

Prevent oesophageal cancer

One of the more serious complications of GORD is the development of Barrett’s oesophagus, a metaplastic change of the lining of the oesophagus that is associated with an increased risk of oesophageal adenocarcinoma.50 Preventing the development of Barrett’s oesophagus and preventing the change of Barrett’s oesophagus to adenocarcinoma should be major naturopathic treatment aims. Preventing reflux episodes, reducing oesophageal inflammation and promoting mucosal healing using the strategies discussed above will be part of this approach. Reducing oxidative stress is an additional approach to this issue, as research has found patients with Barrett’s oesophagus to have lower plasma concentrations of antioxidants (selenium, vitamin C, β-cryptoxanthine and xanthophyll) than GORD patients without Barrett’s oesophagus.51 This can best

be done by encouraging the consumption of antioxidant-rich fruits and vegetables, legumes and whole grain products on a daily basis.

Epidemiological research has found an inverse relationship between dietary intake of zinc and incidence of oesophageal adenocarcinoma52 and animal models have found zinc deficiency to be a significant contributing factor to the development of Barrett’s oesophagus.53 In light of this research, zinc supplementation may also be warranted in GORD sufferers in an attempt to prevent the development of Barrett’s oesophagus (see Chapter 29 on cancer for overarching protocols and interventions).

INTEGRATIVE MEDICAL CONSIDERATIONS

Acupuncture

In a recently published clinical trial, the efficacy of acupuncture was compared to doubling the dose of a proton pump inhibitor (PPI) in patients unresponsive to the standard dose of a PPI. Subjects were randomised to receive either 10 acupuncture sessions over a 4-week period in combination with their original PPI or the same PPI at double the daily dose. At the end of a 4-week treatment period, subjects in the acupuncture group

had significant decreases in daytime heartburn, night-time heartburn, acid regurgitation and dysphagia compared to baseline versus no significant change in the double dose PPI group.55 In subjects unresponsive to initial naturopathic therapy, referral to a traditional Chinese medicine practitioner may be warranted.

Example treatment

Upon analysing her diet, it was found to fit the ‘standard Australian diet’ (SAD)—low in fruits, vegetables and whole grains. In terms of GORD risk factors, she consumed caffeine-containing beverages with each meal, ate lots of fatty foods, consumed chocolate, wine and coffee most evenings after dinner, and ate snacks just before retiring most evenings. To address these GORD risk factors, she was advised not to have any beverages with her meals and to drink fluids only between meals (≥ 1 hr before or ≥ 2 hr after), to switch from full-cream milk to skim, to eliminate all caffeinated and alcoholic beverages, and to avoid other foods known to decrease LOS pressure or worsen GORD symptoms (chocolate, tomatoes and tomato products, and peppermint lollies). She was also advised to eat her evening meals earlier in the evening (prior to 7 p.m.), eat smaller meals in general and advised not to snack after 7 p.m. To help prevent the development of Barrett’s oesophagus, she was advised to consume more fruit daily (three to five pieces), vegetables (five serves daily) and whole grains.

Her BMI was within normal range,21 so there was no need to recommend weight loss. Her incidental exercise levels were quite high—she worked most days each week on her garden acreage—and also walked 3 km at least four times each week.

A herbal tincture was prescribed to acutely relieve her reflux symptoms. Achillea millefolium was prescribed in the tincture for its tannic, phenolic and volatile oil compounds that may increase LOS tone and reduce inflammation.62 Matricaria recutita and Glycyrrhiza glabra will provide a topical anti-inflammatory activity that should soothe the inflamed oesophageal in combination.42,63,64 Glycyrrhiza glabra has the additional benefit of helping to heal the oesophageal mucosa.46 The use of Gentiana lutea as a bitter to enhance digestive activity needs to be monitored as it may potentially cause GORD to be worsened in some individuals.46,65 As indicated in the case, her digestion seems insufficient (bloating and halitosis); hence the use of a bitter may be warranted. Gastrointestinal demulcents (powdered Ulmus fulva and Althaea officinalis) were prescribed to relieve the reflux symptoms and to help protect and heal the oesophageal mucosa.42 Filipendula tea was prescribed to help decrease the oesophageal inflammation and to heal the mucosa. A herbal tincture was prescribed to acutely relieve her symptoms.

As many patients suffering from GORD present with a GORD-related cough (as in this case), it is often advisable to prescribe a herbal mix to provide acute relief of the cough. The herb mix can be taken throughout the day to prevent the cough from

occurring or on an as-needed basis. A typical prescription would contain respiratory demulcents (such as Glycyrrhiza glabra, Althaea officinalis radix and/or Ophiopogon japonicus). This combination effectively soothes the GORD-induced irritation, quickly quelling the tickly cough.

Expected outcomes and follow-up protocols

If the patient successfully implements the dietary recommendations, the GORD symptoms should progressively abate over the course of the following weeks. The signposts of recovery will be seen as a lessening of digestive discomfort, a reduction of regurgitation and other symptoms, such as cough. After cessation of symptoms the patient is advised to continue with the dietary program, the Filipendula ulmaria tea and the gastrointestinal-demulcent powder, and to use the tincture as required. After approximately a month of no symptoms the prescription can be used only as required, although the dietary modifications should continue. The practitioner should be aware that patients may most likely occasionally fall back into poor dietary habits (such as drinking excess alcohol or eating known dietary triggers), so understanding and patience is required with the therapeutic relationship.

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