Completeness of reporting of adverse events in trials of maintenance immunosuppression in kidney transplantation: a systematic review.

Background: Decision-making regarding immunosuppression after transplantation relies on robust evidence on the benefits and harms of available drugs. We aimed to evaluate the reporting of adverse events (AEs) in trials of maintenance immunosuppression in kidney transplantation.

Methods: We conducted a systematic review of published randomized controlled trials of maintenance immunosuppression following kidney transplantation in the Cochrane Kidney and Transplant Register (January 2003-December 2015). Appraisal against the 23-item harms extension of the Consolidated Standards of Reporting Trials statement was conducted.

Results: Of 233 trials, 163 (69%) reported at least one AE. Only 17 (10%) provided definitions or justified the AEs, 13 (8%) described methods and 27 (17%) measured severity. Forty AE types were reported, with gastrointestinal being the most common [116 (71%)]. The frequency of reporting did not reflect known drug side-effect profiles. For example, of 90 calcineurin inhibitor trials, only 22% reported tremors, 3% paresthesia and none anxiety, aggression or mood swings. Trials that reported at least one adverse effect were more likely to be industry funded {adjusted odds ratio [OR] 7.6 [95% confidence interval (CI) 3.4-17.1]}, multicenter [OR 5.9 (95% CI 1.7-18.7)] and with follow-up time <24 months [OR 3.7 (95% CI 1.4-10.2)].

Conclusions: AEs in kidney transplant immunosuppression trials appear to be selectively reported and may be unreliable for clinical decisions. Adherence to the Consolidated Standards of Reporting Trials harms extension should be mandatory to ensure transparent reporting of AEs that are important to patients and clinicians.