Investigation Into Potentially Inappropriate Prescribing Patterns of Loop Diuretics in a Nationally Representative Outpatient Population

Abstract

Background: Loop diuretic therapy effectively treats edema related to heart failure, chronic kidney disease, and liver impairment; however, evidence supporting other indications is lacking. For indications such as hypertension or dependent edema or treatment of adverse events associated with other medications, the benefits likely do not outweigh the risks, putting patients at an unacceptably high risk of poor outcomes. Study Question: What is the proportion of loop diuretic prescribing that occurs in the absence of a diagnosis of heart failure, chronic kidney disease, liver impairment, or other evidence-based indications? Study Design: This was a national, retrospective, cross-sectional investigation conducted using the National Ambulatory Care Survey from 2013 to 2016. Outpatient visits for patients aged 18 years or older prescribed with loop diuretics were included. Measures and Outcomes: The primary end point was the frequency of potentially inappropriate loop diuretic prescribing. The secondary end point was a multivariable regression model that identified predictors of potentially inappropriate loop diuretic utilization. Results: This analysis identified 5261 outpatient visits conducted during the study period in which loop diuretics were prescribed. Of these, 3648 visits (65.8% of weighted visits) were of patients without a history of heart failure, chronic kidney disease, or liver impairment. Positive predictors included age older than 65 years (odds ratio [OR] 1.71; 95% confidence interval [CI] 1.38–2.13), concomitant calcium channel blocker (OR 1.42; 95% CI, 1.09–1.84), sodium-containing medication use (OR 2.78; 95% CI, 1.23–6.25), and office visit with a cardiology specialist (OR 2.84; 95% CI, 2.31–3.50). Conclusions: This analysis identified that loop diuretics are prescribed in the absence of evidence-based indications more frequently than they are prescribed for them. This prescribing pattern creates a unique opportunity for clinicians to optimize patient care. Further study of the outcomes associated with this prescribing pattern is warranted.