In pharmacogenetic medicine, we aim to predict responders to therapy and those who will suffer side effects, so we can choose an alternative agent. In this review, we assessed the current evidence regarding pharmacogenetic guided warfarin, clopidogrel, statin and antihypertensive therapy in stroke. We also considered the barriers to implementation of large scale pharmacogenetic guided therapy in Australia, a nation of many ethnicities.Methods
A computerised literature search was conducted through to November 2016 for warfarin and statins, and October 2016 for antihypertensives and antiplatelets. We utilised Medline, Premedline, Embase and the Cochrane Database of Systematic Reviews using the search term pharmacogenetics, then overall drug class and individual drug names, such as ‘coumarin’, ‘warfarin’, ‘clopidogrel’.Results
We extracted 184 relevant articles for warfarin, 133 for clopidogrel, 89 for statins and 70 for antihypertensives. Overall, the majority of studies were prospective and retrospective observational association studies, with or without controls, which often reported dramatic and contradictory results. We also reviewed a number of randomised controlled trials, narrative and systematic reviews and college guidelines. There is a potential role for pharmacogenetic guided warfarin and clopidogrel therapy. However, neither are ready for prime time, as the utility of genetic testing remains unclear and there are significant barriers to implementation, particularly in a multiethnic population, like Australia. The role for pharmacogenetic guided statin and antihypertensive therapy is less apparent.Conclusions
The current evidence does not support pharmacogenetic guided therapy in stroke in Australia. However, a one-size fits all approach does not work and there is a definite dearth of Australian based pharmacogenetic research, which must be addressed.