Proton-pump inhibitors among adults: a nationwide drug-utilization study

Background: The use of proton-pump inhibitors (PPIs) has grown worldwide, and there are concerns about increased unsubstantiated long-term use. The aim of the study was to describe the real-world use of PPIs over the past decade in an entire national population. Methods: This was a nationwide population-based drug-utilization study. Patterns of outpatient PPI use among adults in Iceland between 2003 and 2015 were investigated, including annual incidence and prevalence, duration of use, and dose of tablet used (lower versus higher), as well as the proportion of PPI use attributable to gastroprotection. Results: We observed 1,372,790 prescription fills over the entire study period, of which 95% were for higher-dose PPIs. Annual incidence remained stable across time (3.3–4.1 per 100 persons per year), while the annual prevalence increased from 8.5 per 100 persons to 15.5 per 100 persons. Prevalence increased with patient age and was higher among women than men. Duration of treatment increased with patients’ age (36% of users over 80 years remained on treatment after 1 year compared with 13% of users aged 19–39 years), and was longer among those initiating on a higher dose compared with a lower dose. The proportion of PPI users concurrently using nonsteroidal anti-inflammatory drugs decreased over the study period, while the proportion concurrently using acetylsalicylic acid, oral anticoagulants, or platelet inhibitors increased. Conclusions: In this nationwide study, a considerable increase in overall outpatient use of PPIs over a 13-year period was observed, particularly among older adults. Patients were increasingly treated for longer durations than recommended by clinical guidelines and mainly with higher doses.