Prophylaxis and treatment of cancer-related dyspnea with pharmacologic agents: A systematic review and network meta-analysis

INTRODUCTION: Cancer-related dyspnea is a common symptom in patients with cancer. It has also been reported to be a predictor of poorer prognosis, which can then change clinical treatment and advance care planning. Currently, no definitive recommendation for pharmacologic agents for cancer-related dyspnea exists. The aim of this systematic review and network meta-analysis is to compare pharmacologic agents for the prophylaxis and treatment of cancer-related dyspnea. METHODS: A search was conducted in the databases of PubMed, Embase, and Cochrane CENTRAL through May 2021. Standardized mean differences (SMDs), as reported by studies or calculated from baseline and follow-up dyspnea scores, were amalgamated into a summary SMD and 95% confidence interval (CI) using a restricted maximum likelihood multivariate network meta-analysis. RESULTS: Twelve studies were included in this review; six reported on prophylaxis of exertional dyspnea, five on treatment of everyday dyspnea, and one on treatment of episodic dyspnea. Morphine sulfate was better at controlling everyday dyspnea than placebo (SMD 1.210; 95% CI: 0.415-2.005). Heterogeneity in study design and comparisons, however, led to some concerns with the underlying consistency assumption in network meta-analysis design. CONCLUSION: Optimal pharmacologic interventions for cancer-related dyspnea could not be determined based on this analysis. Further trials are needed to report on the efficacy of pharmacologic interventions for the prophylaxis and treatment of cancer-related dyspnea.