Gaps in the evidence base of opioids for refractory breathlessness. A future work plan?

Predictors of Morphine Efficacy for Dyspnea in Inpatients with Chronic Obstructive Pulmonary Disease: A Secondary Analysis of JORTC-PAL 07

Objective: This study aimed to explore the predictors of morphine efficacy in the alleviation of dyspnea in COPD.

Background: Dyspnea is prevalent in patients with chronic obstructive pulmonary disease (COPD) and often persists despite conventional treatment.

Methods: A secondary analysis of a multi-institutional prospective before–after study was conducted focusing on morphine use for alleviating dyspnea in COPD patients. Subjects included COPD patients with dyspnea at seven hospitals in Japan. Patients received 12 mg/day of oral morphine (or 8 mg/day if they had low body weight or renal impairment). Univariate and multivariate logistic regression analyses were performed with numerical rating scale (NRS) score of the current dyspnea intensity in the evening of day 0, Eastern Cooperative Oncology Group Performance Status (ECOG PS; ≤2 or ≥3), age, and partial arterial pressure of carbon dioxide (PaCO₂) as independent factors; an improvement of ≥1 in the evening NRS score of dyspnea from day 0 to 2 was the dependent factor.

Results: Thirty-five patients were enrolled in this study between October 2014 and January 2018. Excluding one patient who did not receive the treatment, data from 34 patients were analyzed. In the multivariate analysis, lower PaCO₂ was significantly associated with morphine efficacy for alleviating dyspnea (odds ratio [OR] 0.862, 95% confidence interval [CI] 0.747–0.994), whereas the NRS of dyspnea intensity on day 0 (OR 1.426, 95% CI 0.836–2.433), ECOG PS (OR 4.561, 95% CI 0.477–43.565), and patients' age (OR 0.986, 95% CI 0.874–1.114) were not.

Discussion: Morphine can potentially alleviate dyspnea in COPD patients with lower PaCO₂. Trial registration: UMIN000015288 (http://www.umin.ac.jp/ctr/index.htm)

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

BACKGROUND

Dyspnea is one of the most distressing symptoms encountered by advanced cancer patients. In this study, we aimed to evaluate the role of opioids in the management of cancer-related dyspnea.

METHODS

A systematic review and meta-analysis based on Randomized Controlled Trials was conducted in the databases PUBMED, EMBASE, and Cochrane Central Register of Controlled Trials testing the effect of opioids in relieving cancer-related dyspnea. Subgroup and sensitivity analyses were performed to evaluate various types of opioids in dyspnea management and stabilization of the study respectively.

RESULTS

Eleven RCTs fulfilled the eligibility criteria and had a total of 290 participants. Nine of these studies were included in meta-analyses. Compared with control, opioid therapy showed a small positive effect in dyspnea, SMD-0.82 (95%CI = -1.54 to -0.10) and Borg score, WMD-0.95 (95%CI = -1.83 to -0.06); Opioid therapy did not increase the risk of somnolence, OR0.93 (95%CI = 0.34 to 2.58), whereas a negative effect on respiratory rate was observed,WMD-1.89 (95%CI = -3.36 to -0.43); Also, there was no evidence to suggest improved performance of the 6MWT test, WMD6.49 (95%CI = -34.23 to 47.21), or the level of peripheral oxygen saturation, WMD0.33 (95%CI = -0.59 to 1.24) after opioid therapy. Subgroup analysis yielded a small positive effect for morphine on dyspnea, SMD-0.78 (95%CI = -1.45 to -0.10), whereas fentanyl showed no improvement in dyspnea, SMD-0.44 (95%CI = -0.89 to 0.02). Sensitivity analysis showed no changes in the direction of effect when any one study was excluded from the meta-analyses.

CONCLUSIONS

Our systematic review and meta-analysis indicated low quality evidence for a small positive effect of opioids in cancer-related dyspnea. Evidence for safety is insufficient as comprehensive adverse events were not adequately reported in studies.

Oral morphine drops for prompt relief of breathlessness in patients with advanced cancer-a randomized, double blinded, crossover trial of morphine sulfate oral drops vs. morphine hydrochloride drops with ethanol (red morphine drops)

PURPOSE

Episodic breathlessness is frequent in palliative cancer patients. Opioids are the only pharmacological agents with sufficient evidence in treatment. In Denmark, the main recommendation is red morphine drops (RMD), an off-label solution of morphine, ethanol, and red color (cochenille) described since 1893 (Pharmacopoea Danica). In 2015, the Danish Medicines Agency increased focus on off-label medicines and recommended registered morphine drops without ethanol instead. However, our palliative patients told us that RMD was better. For that reason, we conducted a clinical trial to clarify any perceived difference between the two types of drops.

METHODS

We conducted a randomized, double blinded, crossover trial. Patients were asked to perform standardized activity (2-min walk) aiming to provoke breathlessness. Primary endpoint (breathlessness NRS) and secondary endpoints (saturation, pulse, respiratory frequency) were measured before (t = 0) and after test medicine at t = 1, t = 3, t = 5, t = 10, and t = 20 min. After 2-4 days (washout period), the patients repeated the test, receiving the alternative drops in a blinded setup (crossover).

RESULTS

In the first 3 min, the relative drop in breathlessness for morphine drops with ethanol (RMD) was significant more than for morphine drops without ethanol. We found no significant difference in secondary endpoints.

CONCLUSIONS

A conclusion could be that ethanol might facilitate morphine absorption in the mouth. Our results needs further research of opioid absorption in the mouth as well as trials, testing morphine vs. more lipophilic opioids. The RMD drops are cheap, easy to use, and noninvasive and keep the patient independent of health care professionals.

Managing chronic breathlessness in the community

Breathlessness or dyspnoea is a subjective experience that can be described as an unpleasant or uncomfortable awareness of breathing. It is a subjective experience for patients and often they learn to adapt to the limitations caused by their condition, which makes their breathlessness less apparent to others. Breathlessness can be subdivided in the context of chronic refractory breathlessness, such as acute breathlessness, which is either an episodic breathlessness or breathlessness crisis. Chronic refractory breathlessness is defined as breathlessness at rest or on minimal exertion that will persist chronically despite optimal treatment of the underlying causative factors. The role of the community nurse in managing the breathless patient should involve differentiating between different types of breathlessness and knowing how to effectively manage it in a holistic manner.

Fentanyl treatment for end-of-life dyspnoea relief in advanced cancer patients

PURPOSE

We assessed the effects of subcutaneous-endovenous fentanyl on dyspnoea in a cohort of advanced cancer patients.

METHODS

We performed a retrospective study in a cohort of advanced cancer patients with dyspnoea at rest who received subcutaneous or intravenous fentanyl. Patients with no shortness of breath at rest or at minimal exertion, no rescue doses per 24 h, were deemed to be responders to fentanyl. The period of assessment was 6 days from the beginning of fentanyl treatment.

RESULTS

Seventy-two patients were evaluated: 65% males, 50% ≥ 75 years, Palliative Performance Scale (PPS) median of 30%. Seventy-six percent of the patients were responders to fentanyl. Fentanyl efficacy was not statistically related to age, gender, cancer type, previous opioid treatment, steroid and midazolam doses and PPS. The median fentanyl dose in responders was 25 mcg/h (interquartile range 12-70). It was significantly related to age (37 vs 12 mcg/h, for ≤ 75 vs > 75 years, respectively; p = 0.02). There was not a significant difference between fentanyl doses of responders and non-responder patients. Thirty-six, 23 and 15 patients had sustained improvements in dyspnoea over 48, 72 and 96 h. Fentanyl had no significant toxicity. The length of inclusion in the study and exclusion were related to low performance status (hazard ratio 0.961; _95%CI 0.927-0.996; Cox-regression) but not to fentanyl doses (hazard ratio 0.875; _95%CI 0.620-1.234; Cox-regression).

CONCLUSION

Our preliminary data suggest that subcutaneous-endovenous fentanyl may be associated with dyspnoea relief in dying patients. Further research is needed to confirm these findings.

Prescription of opioids for breathlessness in end-stage COPD: a national population-based study

BACKGROUND

Low-dose opioids can relieve breathlessness but may be underused in late-stage COPD due to fear of complications, contributing to poor symptom control.

OBJECTIVES

We aimed to study the period prevalence and indications of opioids actually prescribed in people with end-stage COPD.

METHODS

The study was a longitudinal, population-based study of patients starting long-term oxygen therapy (LTOT) for COPD between October 1, 2005 and June 30, 2009 in Sweden. A random sample (n=2,000) of their dispensed opioid prescriptions was obtained from the national Prescribed Drugs Register from 91 days before starting LTOT until the first of LTOT withdrawal, death, or study end (December 31, 2009). We analyzed medication type, dispensed quantity, date of dispensing, and indications categorized as pain, breathlessness, other, or unknown.

RESULTS

In total, 2,249 COPD patients (59% women) were included. During a median follow-up of 1.1 (interquartile range 0.6-2.0) years, 1,034 patients (46%) were dispensed ≥1 opioid prescription (N=13,722 prescriptions). The most frequently prescribed opioids were tramadol (23%), oxycodone (23%), morphine (16%), and codeine (16%). Average dispensed quantity was 9.3 (interquartile range 3.7-16.7) defined daily doses per prescription. In the random sample, the most commonly stated indication was pain (97%), with only 2% for breathlessness and 1% for other reasons.

CONCLUSION

Despite evidence that supported the use of opioids for the relief of breathlessness predating this study, opioids are rarely prescribed to relieve breathlessness in oxygen-dependent COPD, potentially contributing to less-than-optimal symptom control. This study creates a baseline against which to compare future changes in morphine prescribing in this setting.

Hospital without dyspnea: rationale and design of a multidisciplinary intervention

Dyspnea is a common and disabling symptom of respiratory and heart diseases, which is growing in incidence. During hospital admission, breathlessness is under-diagnosed and under-treated, although there are treatments available for controlling the symptom. We have developed a tailored implementation strategy directed to medical staff to promote the application of these pharmacological and non-pharmacological tools in dealing with dyspnea. The primary aim is to decrease the rate of patients that do not receive an adequate relief of dyspnea. This is a four-stage quasi-experimental study. The intervention consists in two teaching talks that will be taught in Cardiology and Respiratory Medicine Departments. The contents will be prepared by Palliative Care specialists, based on available tools for management of dyspnea and patients' needs. A cross-sectional study of dyspnea in hospitalized patients will be performed before and after the intervention to ascertain an improvement in dyspnea intensity due to changes in medical practices. The last phase consists in the creation of consensus protocols for dyspnea management based in our experience. The results of this study are expected to be of great value and may change clinical practice in the near future and promote a changing for the better of dyspnea care.

Management of refractory breathlessness with morphine in patients with chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD) is a progressive, incurable illness, which leads to significant morbidity over long periods of time and mortality. Treatment aims to reduce symptoms, improve exercise capacity and quality of life, reduce exacerbations, slow disease progression and reduce mortality. However, breathlessness is common in patients with advanced COPD and remains undertreated. As all reversible causes of breathlessness are being optimally managed, consideration should be given to specific non-pharmacological and pharmacological treatment strategies for breathlessness. Low dose morphine has been shown to reduce safely and effectively breathlessness in patients with severe COPD and refractory dyspnoea. However, despite numerous guidelines recommending opioids in this clinical setting, many barriers limit their uptake by clinicians. Integration of palliative care earlier in the disease course can help to improve symptom control for people with severe COPD and refractory breathlessness. A multidisciplinary approach involving both respiratory and palliative care teams offers a new model of care for these patients.

Palliative Care in Advanced Lung Disease: The Challenge of Integrating Palliation Into Everyday Care

The tendency toward "either/or" thinking (either cure or comfort) in traditional biomedical care paradigms does little to optimize care in advancing chronic illness. Calls for improved palliation in chronic lung disease mandate a review of related care gaps and current clinical practices. Although specialist palliative services have their advocates, adding yet another element to an already fragmented, often complex, care paradigm can be a challenge. Instead, we propose a more holistic, patient-centered approach based on elements fundamental to palliative and best care practices generally and integrated as needed across the entire illness trajectory. To support this approach, we review the concept of primary palliative care competencies, identify vulnerability specific to those living with advanced COPD (an exemplar of chronic lung disease), and describe the need for care plans shaped by patient-centered communication, timely palliative responsiveness, and effective advance care planning. A costly systemic issue in the management of chronic lung disease is patients' increasing dependency on episodic ED care to deal with preventable episodic crises and refractory dyspnea. We address this issue as part of a proposed model of care that provides proactive, collaborative case management and the appropriate and carefully monitored use of opioids. We encourage and support a renewed primary care resolve to integrate palliative approaches to care in advanced lung disease that, in concert with judicious referral to appropriate specialist palliative care services, is fundamental to what should be a more sustainable systematic improvement in palliative care delivery.

Characteristics of episodic breathlessness as reported by patients with advanced chronic obstructive pulmonary disease and lung cancer: Results of a descriptive cohort study

BACKGROUND

Episodic breathlessness is one form of refractory breathlessness. Better understanding of the symptom is necessary for effective management.

AIM

The aim was to describe the characteristics of episodic breathlessness in patients with advanced chronic obstructive pulmonary disease or lung cancer.

DESIGN

This is a longitudinal cohort study. Outcomes were assessed monthly by up to 13 telephone interviews: peak severity (modified Borg scale: 0-10), duration, frequency, and timing of breathlessness episodes. Data from each episode were pooled and analyzed using descriptive statistics. Associations between outcomes were explored by correlation coefficients.

SETTING/PARTICIPANTS

Patients with chronic obstructive pulmonary disease (Global Initiative for Chronic Obstructive Lung Disease classification stage III or IV) or primary lung cancer (any stage) were recruited in two inpatient units (internal medicine) and two outpatient clinics in Oldenburg, Germany.

RESULTS

A total of 82 patients (50 chronic obstructive pulmonary disease, 32 lung cancer), mean age (standard deviation) 67 years (8 years) and 36% female, were included reporting on 592 breathlessness episodes (chronic obstructive pulmonary disease: 403, lung cancer: 189). Peak severity was perceived significantly higher in chronic obstructive pulmonary disease patients than in lung cancer patients (mean (standard deviation) Borg scale: 6.2 (2.1) vs 4.2 (1.9); p < 0.001). Episodes described by chronic obstructive pulmonary disease patients were longer than those described by lung cancer patients (median (range): 7 min (0-600) vs 5 min (0.3-120), p = 0.002)). Frequency was similar and most often daily in both groups. Severity and frequency of episodes were correlated in lung cancer patients (r = 0.324, p = 0.009).

CONCLUSION

Most breathlessness episodes are short (minutes) and severe with significant differences between chronic obstructive pulmonary disease and lung cancer patients. Effective management strategies are warranted to improve symptom relief and coping.

Opioids, Exertion, and Dyspnea

The aim of this paper is to review the evidence for a role for opioids as an intervention for exertion induced breathlessness with regard to exercise tolerance and breathlessness intensity. Current knowledge about exogenous opioids in exertion-induced breathlessness due to disease comes from a variety of phase 2 feasibility or pilot designs with differing duration, doses, drugs, exercise regimes, underlying aetiologies, and outcome measures. They provide interesting data but firm conclusions for either breathlessness severity or exercise endurance cannot be drawn. There are no adequately powered phase 3 trials of opioids which show improved exercise tolerance and/or exertion induced breathlessness. Low dose oral morphine seems well tolerated by most, and is beneficial for breathlessness intensity. Current work to investigate the effect on exercise tolerance is ongoing.

Definition, categorization, and terminology of episodic breathlessness: consensus by an international Delphi survey

CONTEXT

Episodic breathlessness is a common and distressing symptom in patients with advanced disease. Still, it is not yet clearly defined.

OBJECTIVES

The aim of this work was to develop an international definition, categorization, and terminology of episodic breathlessness.

METHODS

An online Delphi survey was conducted with international breathlessness experts. We used a structured questionnaire to identify specific aspects and reach agreement on a definition, categorization, and terminology (five-point Likert scale). Consensus was defined in advance as ≥70% agreement.

RESULTS

Thirty-one of 68 (45.6%), 29 of 67 (43.3%), and 33 of 67 (49.3%) experts responded in the first, second, and third rounds, respectively. Participants were 20-79 years old, about 60% male, and more than 75% rated their own breathlessness expertise as moderate to high. After three rounds, consensus was reached on a definition, categorization, and terminology (84.4%, 96.3%, and 92.9% agreement). The final definition includes general and qualitative aspects of the symptom, for example, time-limited severe worsening of intensity or unpleasantness of breathlessness in the patient's perception. Categories are predictable or unpredictable, depending on whether any triggers can be identified.

CONCLUSION

There is high agreement on clinical and operational aspects of episodic breathlessness in advanced disease among international experts. The consented definition and categorization may serve as a catalyst for clinical and basic research to improve symptom control and patients' quality of life.

Breathlessness--current and emerging mechanisms, measurement and management: a discussion from an European Association of Palliative Care workshop

BACKGROUND

A pre-conference workshop at the 2012 European Association of Palliative Care meeting discussed the current scientific and clinical aspects of breathlessness.

AIM

To describe a current overview of clinically relevant science in breathlessness.

DESIGN

A collation of workshop presentations and discussions.

DATA SOURCES

Narrative review.

RESULTS

The mismatch between the drive to breathe and the ability to breathe underlies the major theories of breathlessness unifying central processing of peripheral inputs including more recent recognition of the importance of peripheral muscles in mediating efferent inputs, supporting reduction of breathlessness with muscle conditioning. Key questions are whether there is a 'final common pathway' for breathlessness? Are the central nervous system targets for reducing breathlessness identical irrespective of underlying aetiology? Central nervous system functional imaging confirms an ability to differentiate severity (intensity) from affective components (unpleasantness). Breathlessness generates suffering across the community for patients and their caregivers often for long periods. The exertional nature of breathlessness means that reduction rather than elimination of the symptom is the therapeutic goal. No single intervention is likely to relieve chronic refractory breathlessness, but interventions made up of several components may provide incremental relief. Having optimally treated any underlying reversible components, the resultant chronic refractory breathlessness can be treated with pharmacological, psychological and physical therapies to reduce the sensation and its impacts.

CONCLUSION

Ensuring optimal delivery of interventions for breathlessness, whose design is underpinned by improving the understanding in the aetiology and maintenance of breathlessness, is the subject of ongoing controlled clinical trials.

Palliative care for people with non-malignant lung disease: summary of current evidence and future direction

BACKGROUND

The physical and psychosocial needs of patients with chronic non-malignant lung disease are comparable to those with lung cancer. This article will focus on chronic obstructive pulmonary disease, interstitial lung disease and cystic fibrosis as examples of life-limiting, non-curable and non-malignant lung diseases. THE NEED FOR SUPPORTIVE AND PALLIATIVE CARE: Recent national guidance has demanded that palliative care is inclusive of all patients with life-limiting disease, irrespective of diagnosis, and that specialist palliative care teams are involved in the management of patients on a basis of need rather than prognosis.

WHAT IS KNOWN

Despite medical therapy, most patients with moderate to severe chronic obstructive pulmonary disease, interstitial lung disease and cystic fibrosis experience pain, fatigue and dyspnoea, with the majority not getting relief from dyspnoea towards the end of life. Furthermore, dyspnoea causes social isolation and difficulty performing activities of daily living and impairs quality of life. There is an increasing evidence base for the assessment of supportive and palliative care needs, symptom interventions, prognostication, models of service delivery and implications of these for clinical practice and research in non-malignant lung diseases. WHAT IS UNKNOWN: Despite advances, much still remains unknown regarding assessment, management and prognostication in individual chronic non-malignant lung diseases. Although different service models are being used in clinical practice, the optimal model(s) of service delivery remain unknown. IMPLICATION FOR FUTURE RESEARCH, POLICY AND PRACTICE: We describe key areas for further research, which include the need for large, high-quality trials of pharmacological and non-pharmacological interventions and their combinations as well as evaluation of the efficacy and cost-effectiveness of models of care. As access to palliative care is poor for these patients, the barriers to referral need to be understood and reduced, which along with effective working between palliative care teams, with respiratory services backup, should optimise delivery of care in patients with life-limiting non-malignant lung disease.

Characterizing episodic breathlessness in patients with advanced disease

BACKGROUND

Episodic breathlessness is a common and distressing symptom in advanced cancer and nonmalignant diseases but there is a lack of evidence on the characteristics of the symptom.

OBJECTIVE

The aim of this study was to determine the duration, severity, frequency and timing of breathlessness episodes in patients with advanced diseases.

METHODS

Explorative analysis of pooled cross-sectional data on episodic breathlessness collected in personal interviews with patients suffering from chronic obstructive pulmonary disease, lung cancer, chronic heart failure, or motor neuron disease. Interviews were conducted as part of two studies in the UK and in Germany that included the same questions on duration, frequency, timing, and peak severity of breathlessness episodes. Severity was measured on the modified Borg scale (0-10).

RESULTS

One hundred and twenty-nine patients, 61% male, mean age of 67 years (SD 9.8), were included. The episodes described were mainly short (75%≤10 min), severe (mean 6.5 (SD 2.4), and occurred mostly daily. Frequency of episodes triggered by exertion could hardly be determined as these varied depending on patients' activity.

CONCLUSION

Our study reveals clinically important information on the characteristics of episodic breathlessness in patients with advanced diseases. Findings have implications for the treatment of episodic breathlessness since most short-acting drugs in use have a longer onset of action compared to the duration of episodes. We need to determine patient-relevant therapeutic targets for future evaluation of adequate pharmacological and nonpharmacological management options that are urgently warranted.

Opioid therapy for refractory dyspnea in patients with advanced chronic obstructive pulmonary disease: patients' experiences and outcomes

BACKGROUND

Dyspnea that is refractory to conventional treatments affects up to 50% of patients with advanced chronic obstructive pulmonary disease (COPD). Although professional societies recommend opioids in this setting, evidence supporting their use over months is limited. We conducted a multicentre mixed-methods study to understand patients' experiences when opioids are added to optimized conventional treatments for advanced COPD.

METHODS

A total of 44 patients (median age 74, range 51-89 years) agreed to participate in this 6-month study. After baseline assessments, immediate-release morphine sulfate syrup (initially 0.5 mg twice daily) was slowly titrated upward based on weekly assessments of symptoms. We conducted semistructured interviews and collected contemporaneous measures of health-related quality of life, severity of dyspnea, anxiety, depression, global ratings of opioid "helpfulness" and adverse effects before, at 2 months and at 4-6 months after opioids were started.

RESULTS

Of the 44 patients, 32 (73%) completed the trial; 27 (90%) of 30 patients reported the opioid treatment as very (43%) or somewhat (47%) helpful. Three main themes emerged from the patients' overall positive experiences: small gains have big impact; realign hopes with reality; and "try it." Significant improvements were observed in median (interquartile range) scores between baseline and 4-6 months' assessment for health-related quality of life (Chronic Respiratory Questionnaire: 3.5 [2.8-4.0] v. 4.2 [3.6-4.8]; and Chronic Respiratory Questionnaire-Dyspnea domain: 2.8 [2.3-3.6] v. 3.9 [2.8-4.5]) and decreases in severity of dyspnea (numerical rating scale: 7.0 [5.0-8.0] v. 5.0 [4.0-6.0]). Adverse effects were minimal for most patients.

INTERPRETATION

Opioids were a helpful and acceptable intervention for refractory dyspnea in patients with advanced COPD. Many of the patients experienced sustained benefits over months, which supports recent recommendations to consider opioids in this setting.

TRIAL REGISTRATION

ClinicalTrial.gov, no. NCT00982891.

Caring for the older person with chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD), a common disease in elderly patients, is characterized by high symptom burden, health care utilization, mortality, and unmet needs of patients and caregivers. Respiratory failure and dyspnea may be exacerbated by heart failure, pulmonary embolism, and anxiety; by medication effects; and by other conditions, including deconditioning and malnutrition. Randomized controlled trials, which provide the strongest evidence for guideline recommendations, may underestimate the risk of adverse effects of interventions for older patients with COPD. The focus of guidelines on disease-modifying therapies may not address the full spectrum of patient and caregiver needs, particularly the high rates of bothersome symptoms, risk of functional and cognitive decline, and need for end-of-life care planning. Meeting the many needs of older patients with COPD and their families requires that clinicians supplement guideline-recommended care with treatment decision making that takes into account older persons' comorbid conditions, recognizes the trade-offs engendered by the increased risk of adverse events, focuses on symptom relief and function, and prepares patients and their loved ones for further declines in the patient's health and their end-of-life care. A case of COPD in an 81-year-old man hospitalized with severe dyspnea and respiratory failure highlights both the challenges in managing COPD in the elderly and the limitations in applying guidelines to geriatric patients.

Minimally clinically important difference in chronic breathlessness: every little helps

OBJECTIVES

The aim of the study was to determine the minimally clinically important difference (MCID) for breathlessness due to chronic heart failure (CHF).

BACKGROUND

The measurement of breathlessness is difficult because it is subjective and multifactorial. Statistically significant changes in assessment may not be clinically meaningful. This is the first determination of MCID in chronic breathlessness in CHF using patient-rated data.

METHODS

Measurements were made as part of a randomized, controlled, crossover trial of morphine, oxycodone, or placebo for breathlessness in CHF. Breathlessness intensity was assessed at baseline and at the end of each intervention (day 4) using 11-point numerical rating scales (NRS), modified Borg (mBorg) scales, and global impression of change (GC) in breathlessness at day 4. From these data, the change in NRS or mBorg associated with a 1-point change in GC was calculated.

RESULTS

Thirty-five patients completed all study interventions, resulting in 105 data sets. We defined MCID as a 1-point change in GC. Regression analysis found that the MCID, including 95% CIs, equaled change in average NRS breathlessness per 24 hours of 0.5 to 2.0 U (P < .001), change in worst NRS breathlessness per 24 hours of 0.4 to 2.9 (P < .001), change in average mBorg score of 0.2 to 2.0 (P < .001), and change in worst mBorg score as between 0.3 and 1.9 (P < .001). Corresponding effect size calculations lay within the 95% CIs for the regression analysis for each measure.

CONCLUSIONS

A 1-point change in NRS or mBorg score is a reasonable estimate of the MCID in average daily chronic breathlessness in CHF.