1

What is gastro-oesophageal reflux disease?

Gastro-oesophageal reflux disease (GORD) represents reflux of gastric acid greater than the normal amount, resulting in symptoms or evidence of oesophageal mucosal injury.

2

What is the epidemiology of GORD?

Heartburn affects 5-10% of the Western population daily.

After 10 years, 90% of these individuals still suffer with heartburn.

GORD increases with age.

Although GORD occurs in equal frequency in men and women, there is an increased incidence of oesophagitis (3:1) and Barrett’s oesophagus (10:1) in men.

3

What is the pathophysiology of GORD?

Competence of the gastro-oesophageal junction (GOJ) is maintained by the presence of:

a)

anatomical factors – including the crural muscle of the diaphragmatic hiatus, acute angle of His and intra-abdominal length of the oesophagus;

b)

physiological factors – including lower oesophageal sphincter (LOS) tone, effective oesophageal motility and effective gastric emptying.

GORD is caused by incompetence of these anti-reflux barriers at the GOJ, when intragastric pressure exceeds LOS pressure (Figure 1).

Prolonged contact of the acidic refluxate (pH <4) with the oesophagus can produce oesophageal mucosal injury.

Inflammation of the oesophageal mucosa may affect neuromuscular function, causing LOS dysfunction and impaired oesophageal motility (Figure 2).

4

What are the risk factors for developing GORD?

There are a number of factors that may contribute to the development of GORD, including:

a)

impaired oesophageal mucosal resistance;

b)

poor oesophageal motility and subsequent reduced clearance of the refluxate;

c)

lower oesophageal sphincter (LOS) dysfunction:

i)

displacement of the LOS – from the normal intra-abdominal position of the LOS with loss of intra-abdominal pressure on the oesophagus;

ii)

poor LOS tone;

iii)

transient LOS relaxation (TLOSR);

d)

increased intra-abdominal pressure, associated with pregnancy or morbid obesity can compress the stomach and cause the gastro-oesophageal junction to migrate into the chest;

e)

delayed gastric emptying;

f)

increased gastric acid production.

Some reflux of gastric contents occurs in most individuals but these episodes are usually short-lived and the refluxate is rapidly cleared from the oesophagus.

Patients with a hiatus hernia may have several factors that increase their risk of developing GORD, including:

a)

reduced effectiveness of the diaphragmatic crura, caused by an enlarged diaphragmatic hiatus or displacement of the LOS;

b)

decreased length of the LOS;

c)

lack of intra-abdominal length of the oesophagus subject to intra-abdominal pressure.

5

What are the complications of GORD?

Reflux oesophagitis – oesophageal mucosal inflammation.

Oesophageal ulceration.

Oesophageal stricture – circumferential fibrosis that frequently occurs in the mid-distal oesophagus and may result in dysphagia to solid foods.

Barrett’s oesophagus – replacement of the oesophageal squamous epithelium with metaplastic columnar epithelium, which is associated with an 11 times increased risk of developing adenocarcinoma.

6

What are the symptoms of GORD?

Heartburn – where symptoms often progress from the supine position, to those in the upright position, to bipositional symptoms (upright or supine position).

Acid regurgitation.

Dysphagia – which may be secondary to severe oesophagitis or the presence of a stricture.

Water brash – excessive salivation.

Odynophagia – pain on swallowing.

Atypical symptoms, including coughing, wheezing, non-cardiac chest pain, hoarseness, sore throat or aspiration pneumonia.

7

What are the investigative findings of a patient with GORD?

Chest radiograph (CXR) – which in the majority of cases is normal but may identify a hiatus hernia or the presence of aspiration pneumonia (Figure 3).

Oesophagogastroduodenoscopy (OGD) – which delineates the gastro-oesophageal anatomy and identifies any complications of GORD, including oesophagitis, stricture formation and Barrett’s oesophagus. In up to 50% of patients with GORD, the OGD is normal.

Oesophageal pH study (Figure 4) – which allows the diagnosis and severity of GORD to be determined (sensitivity and specificity >95%), using the DeMeester score (>14.72 indicates significant reflux), which is based on a number of parameters:

a)

total time with a pH <4;

b)

percentage upright time with a pH <4;

c)

percentage supine time with a pH <4;

d)

number of reflux episodes;

e)

number of reflux episodes >5 minutes;

f)

longest reflux episode.

Oesophageal manometry – which can assess oesophageal motility and functioning of the LOS.

Barium swallow (Figure 5) – which may demonstrate the presence of an oesophageal stricture.

8

What are the treatment options for a patient with GORD?

Conservative (lifestyle measures):

a)

avoid irritants:

i)

acid foods, including chocolate, high-fat content;

ii)

drinks, including alcohol, coffee;

iii)

medications, including non-steroidal anti-inflammatory drugs, alendronic acid;

b)

eat smaller, more frequent meals;

c)

weight loss (for overweight patients);

d)

avoid eating within 3 hours of sleeping;

e)

elevate the head of the bed;

f)

avoid bending or wearing tight clothes;

g)

avoid drugs that affect oesophageal motility or LOS function, such as nitrates, anticholinergic agents, calcium channel blockers or nicotine.

Pharmacological treatment:

a)

antacids, such as magnesium hydroxide (milk of magnesia) or aluminium hydroxide;

b)

alginates, such as Gaviscon^®;

c)

histamine H₂ antagonists, such as ranitidine;

d)

proton pump inhibitors (PPI), such as omeprazole, pantoprazole;

e)

prokinetic agents, such as metoclopramide.

Surgery:

a)

anti-reflux surgery (see below);

b)

surgery for complications of GORD.

9

What is reflux oesophagitis?

Reflux oesophagitis represents inflammation and damage of the oesophageal mucosa caused by prolonged contact with gastric acid.

10

How is reflux oesophagitis classified (Tables 1 and 2; Figure 6)?

Los Angeles classification (Table 1 and Figure 6).

Savary-Miiler grading system (Table 2).