In one hand, this finding is in line with past studies indicating 8.5% [26] and 13% [9] of patients with Hp-negative duodenal ulcer to have taken NSAIDs, while on the other hand, much higher prevalence such as 50% [27] and 70% [7] was also reported in the literature for the prevalence of Hp-negative DU patients. Here, HP is linked to duodenal ulcer.