Initiation and duration of proton pump inhibitors in the Australian veteran population

Aim: To determine the duration of initial treatment with high strength proton pump inhibitors prescribed for gastro-oesophageal reflux disease in the veteran population in Australia and variance by the medical professional who initiated treatment.

Method: Retrospective cohort study in the Australian veteran population using Department of Veterans' Affairs pharmacy claims data. Veterans who had been dispensed at least one prescription for the high strength proton pump inhibitor indicative of gastro-oesophageal reflux disease between 1 July 2004 and 30 June 2007, were eligible for full health services, and who had not been dispensed any proton pump inhibitor in the previous 12 months were included in the study. The study end-point was time to discontinuation of initial high strength proton pump inhibitor (cessation or switch to maintenance strength) stratified by the type of initial prescriber.

Results: Of the new users of high strength proton pump inhibitors (n= 41 041), 32% discontinued within 8 weeks, and 62% discontinued within 12 months. The median treatment duration was: 195 days (95% CI, 186-205) for patients with hospital-initiated therapy (n= 12 294), 124 days (95% CI, 121-127) for patients with treatment initiated by general practitioners (n= 25 327) and 112 days (95% CI, 104-121) for patients with treatment initiated by specialist (n= 3420).

Conclusions: Only one-third of the Australian veteran patients who initiated high strength proton pump inhibitor treatment for gastro-oesophageal reflux disease discontinued (ceased or stepped down) within 8 weeks consistent with guideline recommendations. The majority continued treatment beyond recommended durations. This is not directly attributable to the initiating prescriber.