Superintendent Pharmacist University of Dundee Dundee, United Kingdom
Background: Hyperuricemia is associate with the development of hypertension. Whether lowering uric acid improves blood pressure is still debated. The Febuxostat versus Allopurinol Streamlined Trial (FAST) was a randomised controlled trial comparing the cardiovascular safety of febuxostat and allopurinol in individuals with symptomatic hyperuricemia previously receiving allopurinol.
Objectives: To observe the effect of the xanthine oxidase inhibitors Allopurinol and Febuxostat on blood pressure in adults with chronic hyperuricemia in the FAST study.
Methods: At the FAST screening visit, patients were invited to participate in the Blood Pressure (BP) sub-study. A validated BP monitor and an instruction booklet were provided. Systolic (SBP) and diastolic (DBP) home BP measurements was taken over four consecutive days, three times each in the morning and evening. BPs were recorded at baseline (on allopurinol therapy), after 7-days allopurinol washout, and 8 weeks after randomisation to febuxostat or allopurinol. Differences in SBP and DBP in the allopurinol and febuxostat cohorts were compared between washout and 8-weeks post randomisation. The repeated measure BP data were analysed using mixed models (proc mixed in SAS v9.4).
Results: Between December 2012 and January 2014, 298 FAST participants consented to the BP sub-study. 223 participants who submitted a complete set of BP data were included in the analysis; 104 were randomised to Allopurinol and 119 to Febuxostat. Overall mean change in BP from washout to 8 weeks of randomised treatment was not significant in either group [Mean BP change in Allopurinol arm: SBP -0.24 mmHg (95% CI -3.48, 2.99) p =0.88; DPB 0.74 mmHg (95% CI -1.51, 2.99) p=0.51. Mean BP change in Febuxostat arm: SBP -0.58 (95% CI -3.89, 2.73) p=0.73; DBP -0.35 (95% CI -2.42, 1.72) p=0.74]. No significant BP differences were observed between groups at each time point.
Conclusions: There was no significant difference in the effect of allopurinol or febuxostat on blood pressure after 8 weeks of randomised therapy in the FAST study.
