Assessment of Outcome
Incident CKD was identified based on medical history and linkage to data on primary care and hospital admissions. We used the chronic renal failure (synonym of CKD) variables provided by UK Biobank, which integrated information from these different data sources (including primary care, hospital admissions, self-report and death register). Details of the algorithms used to identify CKD could be found on the UK Biobank website (www.ukbiobank.ac.uk ). Participants with prevalent of any type of renal failure were excluded at baseline. At the time of analysis, complete follow-up was available up to 31 October 2017 for England and Wales and 31 October 2016 for Scotland.