Low-dose, Nontitrated Dexmedetomidine Trials: Clarifying Possible Coenrollment

Author: Michael C. Reade, M.B.B.S., D.Phil.

Anesthesiology 8 2017, Vol.127, 398.

To the Editor:

In the November 2016 issue of Anesthesiology, Wu et al.¹  reported the results of their randomized controlled trial of low-dose (0.1 µg kg⁻¹ h⁻¹, nontitrated) dexmedetomidine in 76 nonmechanically ventilated noncardiac surgery patients aged 65 yr or older (an off-label use), in which dexmedetomidine was found to improve several polysomnographic and self-reported indices of sleep quality. In August 2016, the same group published in the Lancet the results of an identical drug protocol applied to 700 patients meeting almost identical inclusion/exclusion criteria.²  This Lancet paper reported a significantly lower incidence of delirium in patients treated with dexmedetomidine compared to the control group, along with several congruent secondary endpoints such as improved subjective sleep quality. One of the two Lancet trial sites, the Peking University First Hospital, was also the location of the Anesthesiology study. Patients in the Anesthesiology study were recruited exclusively during the time that the Lancet study was underway in the same hospital. In their Consolidated Standards of Reporting Trials (CONSORT) patient flow diagrams, neither paper indicates that any patients were excluded because they were enrolled in another trial. It could therefore appear, as published, that the results from some patients have been reported twice, rather than that the two papers report entirely separate experimental series. Duplicate publication without acknowledgment overstates the evidence and could, for example, lead a metaanalysis to the wrong conclusion. Both publications report important (indeed, potentially practice-changing) data from well-conducted trials. It would be helpful for the authors to address this potentially superficially misleading appearance and clarify that patients could not, in fact, be enrolled in both trials, perhaps also indicating how patients were chosen for enrollment in one study in preference to the other.

 

Michael C. Reade, M.B.B.S., D.Phil. Burns, Trauma and Critical Care Research Centre, University of Queensland, Queensland, Australia. m.reade@uq.edu.au

References

Wu, XH, Cui, F, Zhang, C, Meng, ZT, Wang, DX, Ma, J, Wang, GF, Zhu, SN, Ma, D : Low-dose dexmedetomidine improves sleep quality pattern in elderly patients after noncardiac surgery in the intensive care unit: A pilot randomized controlled trial. Anesthesiology 2016; 125:979–91

Su, X, Meng, ZT, Wu, XH, Cui, F, Li, HL, Wang, DX, Zhu, X, Zhu, SN, Maze, M, Ma, D : Dexmedetomidine for prevention of delirium in elderly patients after non-cardiac surgery: A randomised, double-blind, placebo-controlled trial. Lancet 2016; 388:1893–902