Among US veterans with pulmonary hypertension (PH), nearly two-thirds of phosphodiesterase-5 (PDE-5) inhibitor prescriptions are inconsistent with PH guidelines, according to the results of a retrospective cohort analysis published in the Annals of the American Thoracic Society.
The investigators sought to determine the national patterns of PDE-5 inhibitor prescribing habits in patients with PH in the Veterans Health Administration (VA). Veterans who had been prescribed a PDE-5 inhibitor at any VA site between 2005 and 2012 were evaluated. The primary outcome of the study was the proportion of patients who were prescribed potentially inappropriate PDE-5 inhibitors, as determined by guideline recommendations (group 1 PH: appropriate; groups 2/3 PH: potentially inappropriate; groups 4/5 PH: uncertain value). Secondary study outcomes included the proportion of treated participants who received guideline-recommended right heart catheterization.
Of 108,777 veterans with PH, 2.6% received daily PDE-5 inhibitor therapy (95% CI, 2.5%-2.7%). Of these treated patients, 19.4% received appropriate therapy (95% CI, 18.0%-20.9%), 61.3% received potentially inappropriate therapy (95% CI, 59.5%-63.1%), and 12.8% received treatment of uncertain value (95% CI, 11.6%-14.1%). During the course of the study, the number of potentially inappropriately treated patients per year increased substantially, from 53 in 2005 to 748 in 2012.
In a randomly selected subset of veterans treated with PDE-5 inhibitors, 47.8% had documented right heart catheterization to confirm the presence or type of PH (95% CI, 41.3%-54.5%). When the researchers factored into their treatment algorithm the presence of and the data from patients with right heart catheterization, only 11.7% of individuals received clearly appropriate therapy (95% CI, 8.0%-16.8%).
The investigators concluded that the PDE-5 inhibitor prescriptions that are inconsistent with PH guidelines may expose patients to potential harm, as well as impose a financial burden on the healthcare system. Additional study is warranted to clarify the effects of these prescribing patterns on outcomes in patients with PH.
Kim D, Lee KM, Freiman MR, et al. Phosphodiesterase-5-inhibitor therapy for pulmonary hypertension in the US: actual vs recommended use [published online February 27, 2018]. Ann Am Thorac Soc. doi:10.1513/AnnalsATS.201710-762OC