The impact of diuretic use and ABCG2 ABCG2 genotype on the predictive performance of a published allopurinol dosing tool

摘要

Aim This research aims to evaluate the predictive performance of a published allopurinol dosing tool. Methods Allopurinol dose predictions were compared to the actual dose required to achieve serum urate (SU) 0.36?mmol?l ?1 using mean prediction error. The influence of patient factors on dose predictions was explored using multilinear regression. Results Allopurinol doses were overpredicted by the dosing tool; however, this was minimal in patients without diuretic therapy (MPE 63?mg?day ?1 , 95% CI 40–87) compared to those receiving diuretics (MPE 295?mg?day ?1 , 95% CI 260–330, P ??0.0001). ABCG2 genotype (rs2231142, GT) had an important impact on the dose predictions (MPE 201, 107, 15?mg?day ?1 for GG, GT and TT, respectively, P ??0.0001). Diuretic use and ABCG2 genotype explained 53% of the variability in prediction error ( R 2 ?=?0.53, P ?=?0.0004). Conclusions The dosing tool produced acceptable maintenance dose predictions for patients not taking diuretics. Inclusion of ABCG2 genotype and a revised adjustment for diuretics would further improve the performance of the dosing tool.