A 45-year-old man who smokes has been diagnosed with a peptic ulcer. What is the strongest predisposing factor for his condition?

The strongest predisposing factor for the development of a peptic ulcer in this scenario is ibuprofen use. Nonsteroidal anti-inflammatory drugs (NSAIDs) like ibuprofen can significantly contribute to the formation of peptic ulcers due to their mechanism of inhibiting the production of prostaglandins. Prostaglandins are important for maintaining the protective mucosal barrier in the stomach and intestines. When their production is reduced, the mucosa becomes more susceptible to damage from gastric acid and digestive enzymes, increasing the risk of ulcer formation.

While smoking and other factors such as diet and alcohol intake can also contribute to the risk of peptic ulcers, the regular use of NSAIDs like ibuprofen is particularly notable for its direct impact on gastrointestinal mucosal protection. This relationship is well-established in clinical literature, making ibuprofen use a key consideration when evaluating predisposing factors for peptic ulcer disease.