Environmental - lifestyle related factors.

The prevalence of gastro-oesophageal reflux disease (GORD) has been increasing worldwide. This increase is likely associated with the increased prevalence of obesity, the ageing of the population and the decreased prevalence of Helicobacter pylori (Hp) infection. These different environmental factors interact with GORD pathogenesis in a potentially negative way. Oesophago-gastric junction (OGJ) competence, oesophageal clearance mechanisms and reflux causticity are involved in GORD pathophysiology. Obesity alters GORD pathogenesis by disrupting the OGJ and increasing intragastric pressure. Additionally, the number of transient lower oesophageal sphincter relaxations is potentially increased in obese patients. The potential effect of obesity on oesophageal peristalsis and the implication of impaired oesophageal clearance in GORD pathogenesis are still to establish. Ageing also plays an important role in GORD pathogenesis by decreasing lower oesophageal sphincter pressure and impairing oesophageal clearance. However a link between these abnormalities and an increased acid oesophageal exposure has not yet been demonstrated in the elderly. The role of H. pylori and its eradication remain controversial. The type of Hp gastritis may explain the controversial effect. Hp with antral predominant gastritis is responsible for an increased gastric acid secretion and thus promotes GORD. On the opposite spectrum, Hp with diffuse gastritis induces a gastric atrophy and in this particular case, the Hp eradication may restore acid secretion and lead to a more caustic refluxate in patients with predisposing conditions for GORD. The association of GORD and the type of Hp gastritis remains to be confirmed.