Effects of MIdazolam versus MOrphine in acute cardiogenic pulmonary edema and chronic obstructive pulmonary disease: An analysis of MIMO trial

Abstract

Aims: Chronic obstructive pulmonary disease (COPD) is an important comorbidity in heart failure. The MIMO trial showed that patients with acute cardiogenic pulmonary edema (ACPE) treated with midazolam had fewer serious adverse events than those treated with morphine. In this post hoc analysis, we examined whether the presence/ absence of COPD modifies the reduced risk of midazolam over morphine.

Methods: Patients >18 years old clinically diagnosed with ACPE and with dyspnea and anxiety were randomized (1:1) at emergency department arrival to receive either intravenous midazolam or morphine. In this post hoc analysis, we calculated the relative risk (RR) of serious adverse events in patients with and without COPD. Calculating the CochranMantel-Haenszel interaction test, we evaluated if COPD modified the reduced risk of serious adverse events in the midazolam arm compared to morphine.

Results: Overall, 25 (22.5%) of the 111 patients randomized had a history of COPD. Patients with COPD were more commonly men with a history of previous episodes of heart failure, than participants without COPD. In the COPD group, the RR for the incidence of serious adverse events in the midazolam versus morphine arm was 0.36 (95%CI, 0.1-1.46). In the group without COPD, the RR was 0.44 (95%CI, 0.22-0.91). The presence of COPD did not modify the reduced risk of serious adverse events in the midazolam arm compared to morphine (p for interaction =0.79).

Conclusions: The reduced risk of serious adverse events in the midazolam group compared with morphine is similar in patients with and without COPD.