Efficacy and Safety of Opioids in Treating Cancer-Related Dyspnea: A Systematic Review and Meta-Analysis Based on Randomized Controlled Trials

Comparative effectiveness of pharmacological and non-pharmacological interventions for dyspnea management in advanced cancer: A systematic review and network meta-analysis

Objective

This study aimed to evaluate and rank the effectiveness of pharmacological and non-pharmacological interventions for managing dyspnea severity, anxiety, exercise capacity, and health-related quality of life (HRQoL) in patients with advanced cancer.

Methods

A comprehensive search of PUBMED, HINARI, CENTRAL, and ResearchGate was conducted to identify randomized controlled trials (RCTs) published up to March 2024. Network meta-analysis was performed to compare interventions, calculating mean differences (MD) and standardized mean differences (SMD) with 95% confidence intervals (CI). P-scores were used to rank the interventions. Risk of bias was assessed using the Cochrane tool, and the quality of evidence (QOE) was evaluated using the GRADE framework.

Results

A total of 42 RCTs, encompassing 3,832 patients, were included in the analysis. Among the evaluated interventions, high-flow nasal cannula (HFNC) demonstrated the most significant improvement in dyspnea relief (SMD = -1.91; 95% CI: -3.32 to -0.49; QOE: moderate), followed by acupressure/reflexology (SMD = -1.04; 95% CI: -2.02 to -0.06; QOE: very low). Activity rehabilitation was the only intervention that significantly reduced anxiety compared to the control group (SMD = -0.64; 95% CI: -0.97 to -0.32; QOE: very low). While all interventions showed trends of improving exercise capacity, none reached statistical significance. Notably, acupressure/reflexology significantly enhanced HRQoL (SMD = 1.55; 95% CI: 0.22 to 2.88; QOE: moderate).

Conclusions

Non-pharmacological interventions, particularly HFNC and acupressure/reflexology, were more effective than pharmacological approaches in improving dyspnea relief and HRQoL. However, the low quality of evidence underscores the need for high-quality, large-scale trials to confirm these findings and refine treatment strategies for dyspnea management in advanced cancer patients.

Systematic review registration

PROSPERO CRD42023479041.

Practice review: Pharmacological management of severe chronic breathlessness in adults with advanced life-limiting diseases

BACKGROUND

Severe and refractory chronic breathlessness is a common and burdensome symptom in patients with advanced life-limiting disease. Its clinical management is challenging because of the lack of effective interventions.

AIM

To provide practice recommendations on the safe use of pharmacological therapies for severe chronic breathlessness.

DESIGN

Scoping review of (inter)national guidelines and systematic reviews. We additionally searched for primary studies where no systematic review could be identified. Consensus on the recommendations was reached by 75% approval within an international expert panel.

DATA SOURCES

Searches in MEDLINE, Cochrane Library and Guideline International Network until March 2023. Inclusion of publications on the use of antidepressants, benzodiazepines, opioids or corticosteroids for chronic breathlessness in adults with cancer, chronic obstructive pulmonary disease, interstitial lung disease or chronic heart failure.

RESULTS

Overall, the evidence from eight guidelines, 14 systematic reviews and 3 randomised controlled trials (RCTs) on antidepressants is limited. There is low quality evidence favouring opioids in patients with chronic obstructive pulmonary disease, cancer and interstitial lung disease. For chronic heart failure, evidence is inconclusive. Benzodiazepines should only be considered for anxiety associated with severe breathlessness. Antidepressants and corticosteroids should not be used.

CONCLUSION

Management of breathlessness remains challenging with only few pharmacological options with limited and partially conflicting evidence. Therefore, pharmacological treatment should be reserved for patients with advanced disease under monitoring of side effects, after optimisation of the underlying condition and use of evidence-based non-pharmacological interventions as first-line treatment.

Randomized Controlled Trial of a Nurse-Led Brief Behavioral Intervention for Dyspnea in Patients With Advanced Lung Cancer

PURPOSE

In patients with lung cancer, dyspnea is one of the most prevalent and disabling symptoms, for which effective treatments are lacking. We examined the efficacy of a nurse-led brief behavioral intervention to improve dyspnea in patients with advanced lung cancer.

METHODS

Patients with advanced lung cancer reporting at least moderate breathlessness (n = 247) were enrolled in a randomized trial of a nurse-led two-session intervention (focused on breathing techniques, postural positions, and fan therapy) versus usual care. At baseline and weeks 8 (primary end point), 16, and 24, participants completed measures of dyspnea (Modified Medical Research Council Dyspnea Scale [mMRCDS]; Cancer Dyspnoea Scale [CDS]), quality of life (Functional Assessment of Cancer Therapy-Lung [FACT-L]), psychological symptoms (Hospital Anxiety and Depression Scale), and activity level (Godin-Shephard Leisure Time Physical Activity Questionnaire). To examine intervention effects, we conducted analysis of covariance and longitudinal mixed effects models.

RESULTS

The sample (Agemean = 66.15 years; 55.9% female) primarily included patients with advanced non-small cell lung cancer (85.4%). Compared with usual care, the intervention improved the primary outcome of patient-reported dyspnea on the mMRCDS (difference = -0.33 [95% CI, -0.61 to -0.05]) but not the CDS total score at 8 weeks. Intervention patients also reported less dyspnea on the CDS sense of discomfort subscale (difference = -0.59 [95% CI, -1.16 to -0.01]) and better functional well-being per the FACT-L (difference = 1.39 [95% CI, 0.18 to 2.59]) versus the control group. Study groups did not differ in overall quality of life, psychological symptoms, or activity level at 8 weeks or longitudinally over 24 weeks.

CONCLUSION

For patients with advanced lung cancer, a scalable behavioral intervention alleviated the intractable symptom of dyspnea. Further research is needed on ways to enhance intervention effects over the long-term and across additional outcomes.

Malignant Pleural Effusion: A Multidisciplinary Approach

Malignant pleural effusion (MPE) has become an increasingly prevalent complication in oncological patients, negatively impacting their quality of life and casting a shadow over their prognosis. Owing to the pathophysiological mechanisms involved and the heterogeneous nature of the underlying disease, this entity is both a diagnostic and therapeutic challenge. Advances in the understanding of MPE have led to a shift in the treatment paradigm towards a more personalized approach. This article provides a comprehensive review and update on the pathophysiology of MPE and describes the diagnostic tools and the latest advances in the treatment of this complex clinical entity.

Cancer-related breathlessness: opioids other than morphine - comprehensive literature review

INTRODUCTION

Although there is low-quality evidence, there has been an increase in publications on the experience of evaluating and managing cancer-related breathlessness using opioids other than morphine.

METHODS

The author conducted a non-systematic literature review in the PubMed/Medline and Embase until 4 October 2022. Eligible studies have evaluated the efficacy of opioids other than morphine for cancer-related breathlessness. Studies focused on sedation, anaesthesia, paediatric patients, opioid toxicity or basic research were excluded. Reviews/meta-analyses and non-English language publications were also excluded.

RESULTS

A total of 1556 records were identified, of which 23 studies including 469 patients who were treated with fentanyl (n=223), oxycodone (n=171) and hydromorphone (n=75) were considered eligible. Six phase II randomised clinical trials (RCTs), four observational studies and four case reports of fentanyl were found. For breathlessness on exertion, fentanyl yielded promising results, but no RCT showed significant superiority of fentanyl to placebo or morphine. For terminal breathlessness, three RCTs, five non-randomised or observational studies and one case report on oxycodone or hydromorphone were found. Although the results of the observational studies suggested that oxycodone and hydromorphone might be effective alternatives to morphine, the superiority over placebo or non-inferiority to morphine had not been demonstrated in the RCTs.

CONCLUSION

As an alternative to morphine, the author recommends fentanyl for breathless crisis or breathlessness on exertion, and oxycodone or hydromorphone for terminal breathlessness in advanced cancer. Larger and well-designed studies based on firm research policies are needed to confirm this current knowledge.

Patient-Controlled Therapy with Intravenous Oxycodone in Breathlessness due to Advanced Cancer: A Case Report

Dyspnoea is a debilitating symptom in medicine, especially in palliative care. Opioids are the pharmacological agents of choice in the treatment of dyspnoea in palliative medicine. Morphine is the best-studied opioid, and recent literature on oxycodone is encouraging. In refractory cases, opioid infusion and palliative sedation may have to be used. We present a case that used oxycodone in a patient-controlled device specifically for dyspnoea and its effects in relieving dyspnoea in a fast and timely manner. This helped in meeting the demands of the patient and relieving suffering rapidly with less sedation. This case report is unique in the use of an oxycodone patient-controlled device specifically for dyspnoea.

Efficacy of supplemental oxygen for dyspnea relief in patients with advanced progressive illness: A systematic review and meta-analysis

BACKGROUND

Supplemental oxygen is widely used for dyspnea relief; however, its efficacy is yet to be verified. This study aimed to determine the efficacy of supplemental oxygen for dyspnea relief in patients with advanced progressive illness.

METHODS

In this systematic review, several databases, including MEDLINE and EMBASE, were searched to identify eligible randomized controlled trials (RCTs) on the topic published up to September 23, 2019. The search criteria included RCTs investigating patients with advanced progressive illness (advanced cancer, chronic obstructive pulmonary disease, and chronic heart failure). The study protocol was registered with PROSPERO (No. CRD42020161838). Separate analyses were pre-planned regarding the presence or absence of resting hypoxemia.

RESULTS

RCTs investigating supplemental oxygen for dyspnea relief in participants with and without resting hypoxemia (39 and five, respectively) were included in the study. Heterogeneity of supplemental oxygen for dyspnea in RCTs, including participants without resting hypoxemia was evident; hence, post-hoc analyses in four subgroups (supplemental oxygen during exercise or daily activities, short-burst oxygen, continuous supplemental oxygen, and supplemental oxygen during rehabilitation intervention) were conducted. In the meta-analysis, supplemental oxygen during exercise was found to improve dyspnea in patients without resting hypoxemia compared with that in the control (standardized mean difference = -0.57, 95% confidence interval = -0.77 to -0.38). However, supplemental oxygen for the other subgroups failed to improve patients' dyspnea.

CONCLUSION

The results of this systematic review do not support supplemental oxygen therapy for dyspnea relief in patients with advanced progressive illness, except during exercise.

Impact of adding opioids to paravertebral blocks in breast cancer surgery patients: A systematic review and meta-analysis

BACKGROUND

Several breast cancer studies have reported the use of adjuvant opioids with the paravertebral block (PVB) to improve outcomes. However, there is no level-1 evidence justifying its use.

AIM

To elucidate if the addition of opioids to PVB improves pain control in breast cancer surgery patients.

METHODS

We conducted an electronic literature search across PubMed, Embase, Scopus, and Google Scholar databases up to October 20, 2020. Only randomized controlled trials (RCTs) comparing the addition of opioids to PVB with placebo for breast cancer surgery patients were included.

RESULTS

Six RCTs were included. Our meta-analysis indicated significantly reduced 24-h total analgesic consumption with the addition of opioids to PVB as compared to placebo [standardized mean difference (SMD) -1.57, 95% confidence interval (CI): -2.93, -0.21, I 2 = 94%]. However, on subgroup analysis, the results were non-significant for studies using single PVB (SMD: -1.76, 95%CI: -3.65, 0.13 I 2 = 95.09%) and studies using PVB infusion (SMD: -1.30, 95%CI: -4.26, 1.65, I 2 = 95.49%). Analysis of single PVB studies indicated no significant difference in the time to first analgesic request between opioid and placebo groups (mean difference -11.28, 95%CI: -42.00, 19.43, I 2 = 99.39%). Pain scores at 24 h were marginally lower in the opioid group (mean difference -1.10, 95%CI: -2.20, 0.00, I 2 = 0%). There was no difference in the incidence of postoperative nausea and vomiting between the two groups.

CONCLUSION

Current evidence suggests a limited role of adjuvant opioids with PVB for breast cancer surgery patients. Further homogenous RCTs with a large sample size are needed to clarify the beneficial role of opioids with PVB.

P2X Receptors: Potential Therapeutic Targets for Symptoms Associated With Lung Cancer - A Mini Review

Symptoms associated with lung cancer mainly consist of cancer-associated pain, cough, fatigue, and dyspnea. However, underlying mechanisms of lung cancer symptom clusters remain unclear. There remains a paucity of effective treatment to ameliorate debilitating symptoms and improve the quality of life of lung cancer survivors. Recently, extracellular ATP and its receptors have attracted increasing attention among researchers in the field of oncology. Extracellular ATP in the tumor microenvironment is associated with tumor cell metabolism, proliferation, and metastasis by driving inflammation and neurotransmission via P2 purinergic signaling. Accordingly, ATP gated P2X receptors expressed on tumor cells, immune cells, and neurons play a vital role in modulating tumor development, invasion, progression, and related symptoms. P2 purinergic signaling is involved in the development of different lung cancer-related symptoms. In this review, we summarize recent findings to illustrate the role of P2X receptors in tumor proliferation, progression, metastasis, and lung cancer- related symptoms, providing an outline of potential anti-neoplastic activity of P2X receptor antagonists. Furthermore, compared with opioids, P2X receptor antagonists appear to be innovative therapeutic interventions for managing cancer symptom clusters with fewer side effects.

Effects of opioids on respiration assessed by a contact-free unconstraint respiratory monitor with load cells under the bed in patients with advanced cancer

Nocturnal periodic breathing of chronic opioid users has been predominantly documented by the use of polysomnography. No previous studies have assessed the opioid effects of respiratory rhythms throughout the day without the use of physical restraint. We recently developed a contact-free unconstraint vital sign monitoring system with four load cells placed under the bed legs, which allows continuous measurements of respiratory change at the center of gravity on the bed. We aimed to reveal details of the patient's 24-h respiratory status under a monitoring system and to test the hypothesis that respiratory rhythm abnormalities are opioid dose-dependent and worsen during the night time. Continuous 48-h respiratory measurements were successfully performed in 51 patients with advanced cancer (12 opioid-free patients and 39 opioid-receiving patients). Medians of respiratory variables with minimal body movement artifacts were calculated for each 8-h split time period. Compared with opioid-free patients, opioid-receiving patients had slower respiratory rate with higher respiratory rate irregularity without changing tidal centroid shift regardless of the time period. Irregular ataxic breathing was only identified in opioid-receiving patients (33%, P = 0.023) whereas incidence rate of periodic breathing did not differ between the groups. Multivariate regression analyses revealed that opioid dose was an independent risk factor for occurrence of irregular breathing [odds ratio 1.81 (95% CI: 1.39-2.36), P < 0.001], and ataxic breathing [odds ratio 2.08 (95% CI: 1.60-2.71), P < 0.001]. Females developed the ataxic breathing at lower opioid dose compared with males. We conclude that respiratory rhythm irregularity is a predominant specific feature of opioid dose-dependent respiratory depression particularly in female patients with advanced cancer.NEW & NOTEWORTHY Through usage of a novel contact-free unconstraint vital sign monitoring system with four load cells placed under the bed legs allowing continuous measurements of respiratory changes of center of gravity on the bed, this study is the first to assess detailed respiratory characteristics throughout day and night periods without interference of daily activities in patients with advanced cancer receiving opioids. Respiratory rhythm irregularity is a predominant specific feature of opioid dose-dependent respiratory depression particularly in female patients with advanced cancer.

Management of Dyspnea in Advanced Cancer: ASCO Guideline

PURPOSE

To provide guidance on the clinical management of dyspnea in adult patients with advanced cancer.

METHODS

ASCO convened an Expert Panel to review the evidence and formulate recommendations. An Agency for Healthcare Research and Quality (AHRQ) systematic review provided the evidence base for nonpharmacologic and pharmacologic interventions to alleviate dyspnea. The review included randomized controlled trials (RCTs) and observational studies with a concurrent comparison group published through early May 2020. The ASCO Expert Panel also wished to address dyspnea assessment, management of underlying conditions, and palliative care referrals, and for these questions, an additional systematic review identified RCTs, systematic reviews, and guidelines published through July 2020.

RESULTS

The AHRQ systematic review included 48 RCTs and two retrospective cohort studies. Lung cancer and mesothelioma were the most commonly addressed types of cancer. Nonpharmacologic interventions such as fans provided some relief from breathlessness. Support for pharmacologic interventions was limited. A meta-analysis of specialty breathlessness services reported improvements in distress because of dyspnea.

RECOMMENDATIONS

A hierarchical approach to dyspnea management is recommended, beginning with dyspnea assessment, ascertainment and management of potentially reversible causes, and referral to an interdisciplinary palliative care team. Nonpharmacologic interventions that may be offered to relieve dyspnea include airflow interventions (eg, a fan directed at the cheek), standard supplemental oxygen for patients with hypoxemia, and other psychoeducational, self-management, or complementary approaches. For patients who derive inadequate relief from nonpharmacologic interventions, systemic opioids should be offered. Other pharmacologic interventions, such as corticosteroids and benzodiazepines, are also discussed. Additional information is available at www.asco.org/supportive-care-guidelines .