Scarce information is available on gastroesophageal reflux disease in elderly patients. In this study we investigated patterns of gastroesophageal reflux and esophageal lesions in 24 elderly patients with typical gastroesophageal reflux symptoms and a mean age of 69 years (range, 65-76 years), as compared with 147 symptomatic younger patients with a mean age of 45 years (range, 21-64 years). The results of 24-h pH-monitoring and endoscopy showed that the elderly patients had pathologic reflux and reflux esophagitis more frequently than the young patients. The percentage time with pH < 4 in elderly patients with reflux esophagitis was 32.5% in 24 h, as compared with 12.9% in the younger patients with reflux esophagitis (P < 0.05). The elderly patients with reflux esophagitis had more prolonged periods of acid reflux in both the upright and supine positions than the younger patients. Endoscopy showed that 20.8% of elderly patients had grade III/IV esophagitis, whereas only 3.4% of younger patients had grade III/IV esophagitis (p < 0.002). The percentages of grade I/II esophagitis in the two groups were 12.5% and 26.5%, respectively (p < 0.002). We concluded that, compared with younger subjects, elderly patients have more severe gastroesophageal reflux and esophageal lesions.