Monitoring the use of dabigatran etexilate for stroke prevention: compliance with renal function guidelines

INTRODUCTION: Dabigatran etexilate has become widely used in New Zealand, but information relating to when renal function monitoring is being undertaken is lacking. AIM: To investigate if clinically appropriate renal function monitoring is being undertaken in New Zealand primary care for stroke prevention in non-valvular atrial fibrillation patients prescribed dabigatran etexilate. METHODS: New Zealand non-valvular atrial fibrillation patients' prescription and primary care health data were extracted from national administrative databases for the period 1 July 2011 to 31 December 2015. The proportion of patients who had serum creatinine measurements at close proximity to treatment initiation and 12-months post initiation were assessed with 95% confidence intervals (CIs) and compared with Fisher's exact test. Log-rank tests for univariate analysis (gender, age, ethnicity and deprivation) effects on serum creatinine testing at dabigatran etexilate treatment initiation and 12-months post initiation were performed. RESULTS: Overall, 1,948 patients who had been dispensed dabigatran etexilate with available primary care health data were identified. A total of 1,752 (89.9% [CI: 88.5-91.2]) patients had a renal function test at dabigatran etexilate initiation. There were 929 (72.8% [CI: 70.2-75.2]) patients who received >= 1 year supply of dabigatran etexilate and of these 207 (22.3% [CI: 19.6.6-25.1]) had a serum creatinine test 1 year after initiation. Demographic univariate analysis yielded insignificant log-rank tests for association with having serum creatinine measurements, except for Pacific Peoples. DISCUSSION: There appears to be sub-optimal adherence to renal function monitoring for non-valvular atrial fibrillation patients who receive more than 12-months' treatment with dabigatran etexilate in New Zealand primary care.