Date	Event	Description
15 October 2018	New search has been performed	Search run and 21 studies included. 2 studies previously included are now excluded. 4 studies are ongoing and one completed study is awaiting classification pending fuller details of methods and results.
15 October 2018	New citation required and conclusions have changed	Additional evidence has increased certainty in previous findings. New data on blood pressure have been included. We updated the methods to reflect current Cochrane standards e.g. adding a 'Summary of findings' table and PRISMA diagram.