PREDICTORS OF ESOPHAGEAL ACID EXPOSURE IN GASTROESOPHAGEAL REFLUX DISEASE

Objective: To determine the predictive value of patient symptomatology , demography and oesophageal manometry as markers of gastro-oesophagea l reflux. Design: Prospective study of 103 consecutive patients presen ting for the first time to their local district general hospital with heartburn. Methods: Patient symptomatology and demographic details, in cluding age, body mass index and number of cigarettes smoked were reco rded prior to investigation. Patients underwent oesophageal manometry to assess lower oesophageal sphincter pressure and distal oesophageal amplitude. This was followed by ambulatory oesophageal pH monitoring f or 20 h to measure oesophageal acid exposure. Results: Of all the vari ables assessed, only age and epigastric pain correlated with acid expo sure. For every decade increase in age, oesophageal acid exposure incr eased by 23% (confidence interval 5-43%). Multiple regression analysis was performed using age and epigastric pain. This was able to predict less than 13% of the variance in acid reflux. Conclusion: Acid reflux increases with age. Epigastric pain in patients presenting with heart burn is a negative predictive factor and must be inquired about. Howev er, both age and epigastric pain represent only two variables in a mul tifactorial disease.