REN and acute kidney injury: When the analysis was restricted to users of renin-angiotensin system blockers at the time of a UTI (as opposed to adjusting for these drugs as covariates), the risk of acute kidney injury and hyperkalaemia after trimethoprim use were similar to the main analysis; adjusted odds ratio of 1.92 (1.29 to 2.87) for acute kidney injury and 2.22 (1.34 to 3.68) for hyperkalaemia.