Pathophysiology and diagnosis of dyspnea in patients with advanced cancer

Systematic review and meta-analysis of the efficacy of benzodiazepines for dyspnea in patients with cancer

OBJECTIVE

the role of benzodiazepines in relieving dyspnea in patients with cancer has not yet been established. This systematic review and meta-analysis aimed to determine the efficacy and safety of benzodiazepines alone or in combination with opioids for dyspnea in patients with cancer.

METHODS

Cochrane Central Register of Controlled Trials, MEDLINE, EMBASE and Ichushi-Web were searched for articles published from database inception to 23 September 2019. Studies of benzodiazepines alone or in combination with opioids for dyspnea were included. The primary outcome measure was the relief of dyspnea. The secondary outcome measures were anxiety, somnolence and severe adverse events.

RESULTS

of 505 publications initially identified, two trials and one trial were included in the meta-analysis of midazolam alone and in combination with morphine, respectively. With regard to the relief of dyspnea, midazolam alone showed no significant difference compared with morphine alone, with a relative risk of 0.95 (95% confidence interval: 0.47-1.89). Meanwhile, midazolam plus morphine was significantly more effective than morphine alone, with a relative risk of 1.33 (95% confidence interval: 1.02-1.75). For anxiety relief, a meta-analysis could not be performed because of insufficient data. The incidence of somnolence and severe adverse events was not significantly different between the experimental and control groups for either midazolam alone or in combination with morphine.

CONCLUSIONS

benzodiazepines alone do not significantly improve dyspnea compared with opioids alone, but a combination of benzodiazepines and opioids may be more effective. Evidence from randomized controlled trials focusing on patients with cancer has not been generated in recent years. Further appropriately designed randomized controlled trials are required.

Definition of Episodic Dyspnea in Cancer Patients: A Delphi-Based Consensus among Spanish Experts: The INSPIRA Study

BACKGROUND

Episodic dyspnea is an increasingly recognized phenomenon that occurs frequently in patients with cancer. Although numerous definitions have been proposed to describe episodic dyspnea, to date, no common widely accepted definition in Spanish has yet emerged. Without a clear well-accepted definition, it is difficult to design rigorous clinical trials to evaluate candidate treatments for this emerging entity and to compare outcomes among studies.

OBJECTIVE

The aim of the study was to reach a consensus definition of episodic dyspnea in the Spanish language based on professional criteria in cancer patients.

DESIGN

A two-round Delphi study.

SETTING/SUBJECTS

Sixty-one Spanish specialists in medical oncology, radiation oncology, pneumology, palliative care, and pain management participated in the study.

MEASUREMENTS

Sixteen different questions on dyspnea-related terminology, including the definition of episodic dyspnea, were assessed.

RESULTS

The panel of experts reached a consensus on 75% of the 16 assessments proposed: 56.25% in agreement and 18.75% in disagreement. The term that most panelists considered most appropriate to define dyspnea exacerbation was dyspnea crisis. The panelists disagreed that dyspnea exacerbation is equivalent to dyspnea at effort and that the presence of dyspnea at rest is required for exacerbation to occur. However, there was wide agreement that exacerbation may or may not be predictable and can be triggered by comorbidities as well as emotional, environmental, or effort factors.

CONCLUSIONS

The broad consensus reached in this study is a necessary first step to design high-quality methodological studies to better understand episodic dyspnea and improve treatment.

Symptomatic treatment of dyspnea in advanced cancer patients : A narrative review of the current literature

BACKGROUND

Dyspnea is a common, very distressing symptom in advanced cancer patients that challenges them, their relatives, and healthcare professionals. This narrative review summarizes important literature dealing with the evidence for opioids, benzodiazepines, oxygen, and steroids for treating dyspnea in advanced cancer patients.

METHODS

A selective literature search was undertaken in PubMed, Embase, and the Cochrane Library and extended with literature from the reference lists of included studies up to April 2016. Inclusion criteria were that patients were suffering from advanced cancer and were receiving either opioids, benzodiazepines, corticosteroids, or oxygen. The outcome of interest was the reduction of dyspnea measured via a visual analogue scale (VAS), a numerical rating scale (NRS), or a Borg scale. This narrative review describes in detail the findings of 13 studies.

RESULTS

Nine studies deal with the effectiveness of opioids for reducing dyspnea in advanced cancer patients. Five of these found a significant benefit to the use of opioids compared to a placebo. Three found no significant improvements, and two favored combinations of opioids and benzodiazepines. Few high-quality studies were available that used benzodiazepines (n = 3, no difference, significant improvement with midazolam + morphine, significant difference for midazolam) or oxygen (n = 2, both without significant difference). Only one study examined treating dyspnea with steroids in patients with advanced cancer, and that study indicated a benefit of steroids compared to a placebo.

CONCLUSIONS

Opioids are the drug of choice for treating refractory dyspnea in advanced cancer patients. Neither benzodiazepines nor oxygen showed significant benefit. In addition, there is insufficient literature available to draw a conclusion about the effectiveness of steroids for treating persistent dyspnea in advanced cancer patients.

Effectiveness of Corticosteroid Monotherapy for Dyspnea Relief in Patients with Terminal Cancer

Dyspnea is a common symptom in patients with cancer, particularly those with late-stage terminal disease. It markedly affects terminal cancer patients, reducing their quality of life. Reduced quality of life also affects survival; therefore, dyspnea is a prognostic factor. However, the role of corticosteroids, which often are used to alleviate dyspnea, has not been sufficiently validated. In this study, we retrospectively investigated whether corticosteroid monotherapy was effective for dyspnea palliation. The effectiveness rate of corticosteroid therapy was 45% in nine male and two female study subjects (mean age: 74.5 years; range: 64-86 years). No significant differences were found between responders and nonresponders in the first-day corticosteroid doses (25.5 ± 10.86 vs. 36.1 ± 16.39 mg, P = .29) or doses administered on 2 days (47.7 ± 25.99 vs. 72.2 ± 32.78 mg, P = .25). The mean ± standard error assessment score changed significantly from 2.7 ± 0.14 at the beginning of corticosteroid administration to 1.5 ± 0.37 at the time of maximum effect (P = .028); however, the decrease to 2.1 ± 0.25 at the final administration was not significant (P = .068). This indicates that corticosteroid therapy relieved dyspnea and could provide an early-stage treatment option.