Circulating free-radical markers and peptic-ulcer disease

In order to determine whether there are abnormalities of the metabolism of free radicals in duodenal ulcer disease, 23 patients with active duodenal ulcers (0.3-1 cm in diameter), confirmed by endoscopy, have had a blood sample analysed for antioxidants [plasma thiols (PSH) and glutathione (GSH)] and a marker of free radical reaction [malondialdehyde-like material (MDA)]. A sex, age and smoking matched control group was selected from pre-operative patients admitted for minor surgery. No individual had a significant past medical history or was taking any drugs known to cause alterations in the measured chemical entities. MDA levels were increased in the ulcer group: 8.84 (95% confidence intervals 7.5-10.1) compared with 6.62 (5.3-7.9) in the control group (P 0.05). Conversely, the circulating GSH levels were significantly lower in the ulcer group compared with the control group (P <0.01). In addition, the older the patient with ulcer disease, the lower the PSH level and the higher the MDA level (P <0.05). In a separate group of 11 patients with duodenal ulcer disease, there was a significant change in MDA levels and PSH levels when the ulcer had healed, with both values returning to normal. In conclusion, this study suggests that active duodenal ulcer disease may be associated with an abnormal free-radical content of whole blood.