Gastro-oesophageal reflux disease (GORD) occurs more frequently in Europe and North America than in Asia but its prevalence is now increasing in many Asian countries. Many reasons have been given for the lower prevalence of GORD in Asia. Low dietary fat and genetically determined factors, such as body mass index and maximal acid output, may be important. Other dietary factors appear to be less relevant. Increased intake of carbonated drinks or aggravating medicines may influence the increasing rates of GORD in some Asian countries but no strong evidence links other factors, such as the age of the population, smoking or alcohol consumption, to GORD. The management of GORD in Asia is similar to that in Europe and North America but the lower incidence of severe oesophagitis in Asia may alter the approach slightly. Also, because Asians tend to develop stomach cancer at an earlier age, endoscopy is used routinely at an earlier stage of investigation. Gastro-oesophageal reflux disease is essentially a motility disorder, so short-term management of the disease can usually be achieved using prokinetic agents (or histamine (H2)-receptor antagonists). More severe and recurrent GORD may require proton pump inhibitors (PPI) or a combination of prokinetic agents and PPI. The choice of long-term treatment may be influenced by the relative costs of prokinetic agents and PPI.
Gastroesophageal reflux disease (GERD) is a common disease in the West, which now appears to be also increasing in prevalence in the Asian Pacific region. The reasons for this changing epidemiology are two-fold: an increased awareness among doctors and patients, and/or a true increase in the prevalence of the disease. Prevalence rates of reflux esophagitis (RE) of up to 16% and prevalence of GERD symptoms of up to 9% have been reported in the Asian population. However, the frequency of strictures and Barrett's esophagus remain very low. Non-erosive reflux disease (NERD) appears to be the most common form of GERD among Asian patients accounting for 50-70% of cases with GERD. Among Asian patients differences can also be discerned among different ethnic groups. For example, in Malaysia where a multiracial society exists, RE is significantly more common among Indians compared to Chinese and Malays whereas NERD is more frequently seen in the Indian and Malays compared to the Chinese. The reasons for these differences are not known but may indicate both genetic factors and environmental factors peculiar to the particular racial group. GERD has also been increasing in the region demonstrating a time-lag phenomenon compared to the West. Differing predisposition to GERD among different ethnic groups would mean that such an increase would be more prominent among certain racial groups.
Gastroesophageal reflux disease (GERD), previously uncommon in Asia, has now become an important disease in the region. Although much variability exists between studies, most endoscopy-based studies show a prevalence of erosive esophagitis of more than 10%. Symptom-based studies also show a prevalence of 6-10%. Two longitudinal follow-up studies on GERD symptoms have shown an increase with time, and several endoscopy-based time trend studies have also shown a significant increase in erosive reflux esophagitis. Studies on Barrett's esophagus have been confounded by the description of short (SSBE) and long segment (LSBE) Barrett's esophagus. Great variation in prevalence rates has been reported. SSBE vary from 0.1% to more than 20% while LSBE vary from 1-2%. Of the putative causative factors, obesity has been the most important. Many studies have linked GERD-esophagitis as well as occurrence of reflux symptoms with an increase in body mass index (BMI), obesity, especially visceral or central obesity, and metabolic syndrome. A decline in Helicobacter pylori infection with growing affluence in Asia has been broadly thought to result in healthier stomachs and a higher gastric acid output resulting in reflux disease. However, variable results have been obtained from association and H. pylori eradication studies.
As in developed societies, the prevalence of Helicobacter pylori has declined rapidly in Asia. This has been shown in both seroprevalence-based and endoscopy-based studies. While the decline in the incidence of gastric cancer has now been observed, a decrease in peptic ulcer disease has not been so clearly evident. This apparent paradox can be explained by an increase in non-H. pylori associated ulcers - such as those related to non-steroidal anti-inflammatory drugs or idiopathic ulcers. The increase of gastroesophageal reflux disease in Asia has been widely observed and commented on and its relationship to the decline in H. pylori speculated upon. However there have been few conclusive studies from Asia on this subject. While the improved diagnosis and elimination of H. pylori has contributed to its decline, a more basic change involving large segments of the Asian population must be responsible. An improvement in hygiene and living conditions that results from more affluent Asian societies is thought to be a possible cause.
Objectives: This was a cross sectional study conducted in the Paediatric Institute among infants and children with chronic respiratory symptoms with the following objectives: i) to determine the prevalence of gastro-oesophageal reflux in children with persistent respiratory symptoms, ii) to identify the clinical predictors of GOR (Gastro-oesophageal reflux) in children with persistent respiratory symptoms and iii) assess the validity of abdominal ultrasound, barium oesophagogram and chest radiograph in diagnosing GOR in these patients.
Materials and Methods: Forty-four patients were recruited over a period of six months. All the presenting symptoms were identified. The patients were subjected to chest radiograph, abdominal ultrasound, barium oesophagogram and 24-hour pH oesophageal monitoring.
The predictive validity of clinical symptoms, chest radiograph, abdominal ultrasound and barium oesophagogram were assessed. Twenty-four hours oesophageal pH was the gold standard to diagnose GOR.
Results: The mean age of patients was 9.1 months (1-58 months). Thirty-one patients (70.5%) were confirmed to have GOR by pH study. Respiratory symptoms alone were not useful to predict GOR. Cough had the highest sensitivity of 51.6%. stridor, wheeze and choking each had a specificity of 76%. Wheeze, vomiting, choking and stridor were identified to have high specificity (90-100%) in diagnosing GOR when any two symptoms were taken in combination.
Collapse/consolidation was the commonest radiological abnormality but had low sensitivity (35.5%) and specificity (53.8%). However hyperinflation on chest radiograph had a specificity of 92.3% with positive predictive value at 80% in diagnosing GOR. Barium oesophagogram has low sensitivity (37.9%) and moderate specificity (75%) in diagnosing GOR in children with respiratory symptoms.
Abdominal ultrasound was a valid mode of diagnosing GOR when there were three or more reflux episodes demonstrated during the screening period with a specificity of 90.9%. However the sensitivity was low ie 20-25%. The specificity increased to 90-100% when two positive tests were taken in combination (abdominal ultrasound and barium oesophagogram). However the sensitivity remained low (10-20%). Chest radiograph did not improve the predictive value when considered with the above tests. Combination of clinical symptoms were useful as clinical predictors of GOR. In the absence of a pH oesophageal monitoring, a combination of barium oesophagogram and ultrasound may be helpful in diagnosing GOR.
Ethnic differences in gastroesophageal reflux disease (GERD) and its complications as well as racial variations in the prevalence of Helicobacter pylori infection are well documented. Nevertheless, the association between reflux disease, H. pylori, and race has not been adequately explored.
Recent studies indicate that the prevalence of gastroesophageal reflux disease in Asia is either increasing or better recognized. There is a paucity of reliable data on the prevalence of reflux disease in the various races in general and in Malaysia, in particular. The prevalence of erosive esophagitis and Barrett's esophagus in a multiethnic Malaysian population was studied, as well as the relationship of various factors associated with reflux disease. Chinese, Malay, and Indian patients undergoing gastroscopy in a tertiary referral center were assessed for the presence of esophagitis, hiatus hernia, and Barrett's esophagus. Patient demographics and risk factors associated with gastroesophageal reflux disease were also documented. The prevalence of endoscopically documented esophagitis among 1985 patients was 6.1%, the majority of which were mild, Grade I or II (88%). There was a preponderance of Indians with esophagitis, as well as males (P < 0.05) and those with the presence of a hiatus hernia (P < 0.01). Long-segment Barrett's esophagus was found in 1.6% of patients, and short-segment Barrett's in 4.6%. Indians had the highest prevalence of Barrett's esophagus compared with Chinese (P < 0.05) or Malays (P < 0.01). Hiatus hernia and erosive esophagitis were both positively associated with Barrett's metaplasia (P < 0.01). A significant proportion of Malaysian patients undergoing endoscopy has mild reflux esophagitis and Barrett's esophagus. Indian ethnicity and the presence of a hiatus hernia were significantly associated with endoscopic esophagitis and Barrett's metaplasia. These observed racial differences warrant further study.