Peptic ulcer disease in an adult population : the Kalixanda study : a population-based endoscopic study

Introduction: The pattern of symptoms and perception of disease among patients seeking care does, due to health care seeking behaviour, most probably not reflect the true health status in the general population. Upper esophagogastroduodenoscopy (EGD) is considered to be gold standard for upper gastrointestinal (GI) disease assessment, but is seldom used in epidemiological studies. We aimed to explore whether the EG13 affects symptom reporting and sampling among volunteers and to clarify the prevalence of peptic ulcer disease (PUD) and its risk factors in a general adult population. Methods: A random sample of 3,000 adults aged 20-80 years (mean age 50.4), from two Swedish municipalities (n=21,610) was surveyed using a validated postal abdominal symptom questionnaire. A random sub-sample of the responders (n=1,001) was invited, in random order, to undergo an upper endoscopy with biopsies and repeated symptom reporting with the same questionnaire, as well as for blood samples for Helicobacter pylori (H. pylori) serology and other biomarkers, medical history taking, measuring and weighing the subjects. Results: The response rate to the initial questionnaire was 74.2% and the participation rate for those eligible for the upper endoscopy was 73.3% (n=1,001, mean age 54.0 years, 48.8% male). No major social or symptom sampling error was encountered from the selection process, except for an excess of symptom reporters among the youngest subjects (< 35 years). The prevalence of gastroesophageal reflux symptoms (GERS), dyspepsia and the Irritable Bowel Syndrome (IBS) was 40%, 37.6% and 29.6%, respectively. The prevalence of peptic ulcer was 4.1 % (gastric ulcers (GU) n=20; duodenal ulcers (DU) n=21). Nausea and GERS, but not epigastric pain/discomfort, were significant predictors of PUD. Six individuals with GU and two with DU were asymptomatic (in all 20%). Eight DU subjects (38%) lacked evidence of current H. pylori infection. Five (25%) of the GU and four (19%) of the DU were idiopathic (no aspirin/NSAID use, no H. pylori infection and normal Gastrin-17). Smoking, aspirin and obesity were risk factors for GU; smoking, low dose aspirin (¡Ü 160 mg) and H. pylori infection were risk factors for DU. There were more endoscopic findings in obese subjects than in normal weight subjects, but the differences were not significant except for esophagitis and GU; the prevalence of reflux esophagitis in obesity was 26.5% versus 9.3% in normal weight subjects and the corresponding figures for GU were 5.6% and 1.4% respectively. Different types of tobacco use do not seem to have uniform health risks. While smoking increases the risk for PUD, smokeless tobacco use does not, or might even contribute to a lower risk. Use of smokeless tobacco is a significant risk for higher prevalence of reflux esophagitis and for intestinal metaplasia in the antrum (a preneoplastic marker). Conclusions: Valid epidemiology through upper endoscopy is possible. Smoking, aspirin and obesity are risk factors for GU; smoking, low dose aspirin (¡Ül60 mg) and H. pylori infection for DU. Smokeless tobacco is not a risk factor for PUD but most probably not harmless anyhow. Idiopathic ulcer may be more common than anticipated. PUD is often asymptomatic or coexists with atypical symptoms