Prevalence and severity of differing dimensions of breathlessness among elderly males in the population

Exertional breathlessness related to medical conditions in middle-aged people: the population-based SCAPIS study of more than 25,000 men and women

BACKGROUND

Breathlessness is common in the population and can be related to a range of medical conditions. We aimed to evaluate the burden of breathlessness related to different medical conditions in a middle-aged population.

METHODS

Cross-sectional analysis of the population-based Swedish CArdioPulmonary bioImage Study of adults aged 50-64 years. Breathlessness (modified Medical Research Council [mMRC] ≥ 2) was evaluated in relation to self-reported symptoms, stress, depression; physician-diagnosed conditions; measured body mass index (BMI), spirometry, venous haemoglobin concentration, coronary artery calcification and stenosis [computer tomography (CT) angiography], and pulmonary emphysema (high-resolution CT). For each condition, the prevalence and breathlessness population attributable fraction (PAF) were calculated, overall and by sex, smoking history, and presence/absence of self-reported cardiorespiratory disease.

RESULTS

We included 25,948 people aged 57.5 ± [SD] 4.4; 51% women; 37% former and 12% current smokers; 43% overweight (BMI 25.0-29.9), 21% obese (BMI ≥ 30); 25% with respiratory disease, 14% depression, 9% cardiac disease, and 3% anemia. Breathlessness was present in 3.7%. Medical conditions most strongly related to the breathlessness prevalence were (PAF 95%CI): overweight and obesity (59.6-66.0%), stress (31.6-76.8%), respiratory disease (20.1-37.1%), depression (17.1-26.6%), cardiac disease (6.3-12.7%), anemia (0.8-3.3%), and peripheral arterial disease (0.3-0.8%). Stress was the main factor in women and current smokers.

CONCLUSION

Breathlessness mainly relates to overweight/obesity and stress and to a lesser extent to comorbidities like respiratory, depressive, and cardiac disorders among middle-aged people in a high-income setting-supporting the importance of lifestyle interventions to reduce the burden of breathlessness in the population.

Factors most strongly associated with breathlessness in a population aged 50-64 years

Background

Breathlessness is a troublesome and prevalent symptom in the population, but knowledge of related factors is scarce. The aim of this study was to identify the factors most strongly associated with breathlessness in the general population and to describe the shapes of the associations between the main factors and breathlessness.

Methods

A cross-sectional analysis was carried out of the multicentre population-based Swedish CArdioPulmonary bioImage Study (SCAPIS) of adults aged 50 to 64 years. Breathlessness was defined as a modified Medical Research Council breathlessness rating ≥2. The machine learning algorithm extreme gradient boosting (XGBoost) was used to classify participants as either breathless or nonbreathless using 449 factors, including physiological measurements, blood samples, computed tomography cardiac and lung measurements, lifestyle, health conditions and socioeconomics. The strength of the associations between the factors and breathlessness were measured by SHapley Additive exPlanations (SHAP), with higher scores reflecting stronger associations.

Results

A total of 28 730 participants (52% women) were included in the study. The strongest associated factors for breathlessness were (in order of magnitude): body mass index ( SHAP score 0.39), forced expiratory volume in 1 s (0.32), physical activity measured by accelerometery (0.27), sleep apnoea (0.22), diffusing lung capacity for carbon monoxide (0.21), self-reported physical activity (0.17), chest pain when hurrying (0.17), high-sensitivity C-reactive protein (0.17), recent weight change (0.14) and cough (0.13).

Conclusion

This large population-based study of men and women aged 50-64 years identified the main factors related to breathlessness that may be prevented or amenable to public health interventions.

Age-related changes in the neural gating of respiratory sensations in humans

Background

Neural gating of respiratory sensations (NGRS) characterises the brain's ability to filter out repetitive respiratory sensory stimuli. This mechanism plays a crucial role in the neural processing of respiratory stimuli. However, whether ageing affects NGRS in healthy adults is still unclear. Therefore, we aimed to measure the effect of age on NGRS as well as the corresponding S1 and S2 components of the respiratory-related evoked potentials (RREPs).

Methods

Three age groups of healthy adults participated in this study: a young group (YG; age 20-39 years), a middle-aged group (MG; age 40-59 years) and an old group (OG; age ≥60 years). NGRS was measured by the RREPs in the electroencephalogram in response to short-paired respiratory occlusion stimuli (S1 and S2). The S2/S1 ratio of the RREP N1 amplitude (the negative deflection of the RREP at ∼85-135 ms) was used to characterise NGRS.

Results

The results showed a significantly smaller N1 S2/S1 ratio in the YG than in the MG (p=0.01) and OG (p=0.03). Further analysis showed that the S1 N1 amplitude was larger for the YG compared with the MG (p=0.03) and OG (p=0.007). Moreover, age was significantly correlated with the N1 S2/S1 ratio (r=0.43), with higher age relating to higher N1 S2/S1 ratios.

Conclusions

The greater N1 S2/S1 ratios observed in older adults suggest that ageing has a negative impact on the NGRS. This might contribute to increased experiences of respiratory sensations such as dyspnoea in ageing adults.

Impact of wearing a surgical facemask during exercise on dyspnea in patients with chronic pulmonary infections: A randomized crossover study

BACKGROUND

Wearing facemasks in public is effective in preventing viral transmission. However, no study has evaluated the impact of wearing facemasks during exercise on dyspnea in patients with chronic pulmonary infections from multifaceted aspects, including sensory qualities and emotional responses. The aim of this study was to evaluate facemask-related dyspnea during exercise in this patient population.

METHODS

We conducted a randomized crossover study involving adult patients with non-tuberculous mycobacterial pulmonary disease (NTM-PD) or bronchiectasis who participated in exercise sessions, both with (mask-on) and without (mask-off) surgical facemasks. The sensory and emotional dimensions of dyspnea during each exercise session were assessed using the Multidimensional Dyspnea Profile. Statistical analyses were performed to identify factors associated with worsening scores for each dimension.

RESULTS

Thirty-four patients (mean age [standard deviation]: 71.6 [8.6] years) were included in the analysis. The median [interquartile range] total scores for the sensory and emotional dimensions of dyspnea were 3.5 [1, 9.5] (mask-off) vs. 10 [5.5, 23.8] (mask-on) (P < 0.001) and 0 [0, 5] (mask-off) vs. 3 [0.8, 10.3] (mask-on) (P = 0.115), respectively. "Air hunger" was the primary sensory descriptor of mask-related dyspnea. Vital capacity (VC) < 80% of the predicted value was a significant risk factor for worsening sensory dimension scores when wearing masks (odds ratio [95% confidence interval]: 5.5 [1.16-26.1], P = 0.038).

CONCLUSIONS

The findings of this study indicate that patients with NTM-PD or bronchiectasis, particularly those with VC <80% of the predicted value, are likely to experience the sensory dimension of dyspnea during exercise while wearing surgical facemasks.

Should opioids be used for breathlessness and in whom? A PRO and CON debate of the evidence

Purpose of review

The net clinical benefit of opioids for chronic breathlessness has been challenged by recent randomized clinical trials. The purpose was to review and weigh the evidence for and against opioid treatment for chronic breathlessness in people with serious disease.

Recent findings

Evidence to date on the efficacy and safety of opioids for chronic breathlessness was reviewed. Findings supporting a benefit from opioids in meta-analyses of earlier, mostly smaller trials were not confirmed by recent larger trials. Evidence pertains mostly to people with chronic obstructive pulmonary disease but also to people with pulmonary fibrosis, heart failure, and advanced cancer. Taken together, there is no consistent evidence to generally recommend opioids for severe breathlessness or to identify people who are more likely to benefit. Opioid treatment may be tested in patients with intractable breathlessness and limited other treatment options, such as in end-of-life care. Knowledge gaps were identified and recommendations were made for future research.

Summary

Key Points Supportive findings of net benefit of opioids for chronic breathlessness in earlier trials have not been confirmed by recent larger randomized clinical trials. There is no evidence that the opioid treatment improves the person’s exercise capacity or quality of life, and it increases the risk of adverse events. Evidence to date does not support that opioids should generally be recommended for treating breathlessness. In people with intractable symptoms and short expected survival, with few or no treatment options, it may still be reasonable to try opioid treatment with the aim to alleviate severe breathlessness. Research is needed to explore the potential benefit of opioids in selected patient groups. Opioids cannot be generally recommended for treating breathlessness based on insufficient evidence for net clinical benefit.

The modified Medical Research Council scale misclassifies exertional breathlessness among people referred for exercise testing

Background

Exertional breathlessness is a major symptom in cardiorespiratory disease and is often assessed using the modified Medical Research Council (mMRC) questionnaire. The mMRC might underestimate exertional breathlessness in people with impaired exercise capacity who have reduced their physical activity to avoid the symptom. We aimed to evaluate the ability of mMRC to detect abnormally high exertional breathlessness or abnormally low exercise capacity during incremental cycle exercise testing (IET).

Methods

A secondary analysis of data from a randomised controlled trial of outpatients aged 18 years or older referred for IET was carried out. Participants completed the mMRC before IET. Abnormally high exertional breathlessness was defined as a breathlessness (Borg 0-10) intensity response more than the upper limit of normal. Abnormally low exercise capacity was defined using published reference equations. The sensitivity, specificity, accuracy and discriminative ability of each mMRC rating to detect each outcomewas calculated.

Results

92 participants were included; the mean age was 59 years, 61% were male, and 64% and 15% had mMRC 1 and ≥2, respectively. An mMRC ≥2 had the highest accuracy (71%) to detect abnormally high exertional breathlessness, with a specificity of 93% but a sensitivity of only 28%, failing to identify 72% of people with abnormally high exertional breathlessness. The accuracy, specificity and sensitivity for abnormally low exercise capacity was 64%, 88% and 19%, respectively.

Conclusion

Among people referred for clinical exercise testing, the mMRC dyspnoea scale misclassified exertional breathlessness and exercise capacity assessed using cycle IET, with substantial underdetection. A mMRC dyspnoea rating of 0-1 does not preclude the presence of abnormally high exertional breathlessness or abnormally low exercise capacity.

Validation of the Dyspnoea-12 and Multidimensional Dyspnea profile among older Swedish men in the population

Background

The Dyspnoea-12 (D12) and Multidimensional dyspnea profile (MDP) are commonly used instruments for assessing multiple dimensions of breathlessness but have not been validated in older people in the population. The aim of this study was to validate the D12 and MDP in 73-years old men in terms of the instruments’ underlying factor structures, internal consistency, and validity.

Methods

A postal survey was sent out to a population sample of 73-years old men (n = 1,193) in southern Sweden. The two-factor structures were evaluated with confirmatory factor analysis, internal consistency with Cronbach's alpha, and validity using Pearson´s correlations with validated scales of breathlessness, anxiety, depression, fatigue, physical/mental quality of life, body mass index (BMI), and cardiorespiratory disease.

Results

A total 684 men were included. Respiratory and cardiovascular disease were reported by 17% and 38%, respectively. For D12 and MDP, the proposed two-factor structure was not fully confirmed in this population. Internal consistency was excellent for all D12 and MDP domain scores (Cronbach's alpha scores > 0.92), and the instruments’ domains showed concurrent validity with other breathlessness scales, and discriminant validity with anxiety, depression, physical/mental quality of life, BMI, and cardiorespiratory disease.

Conclusions

In a population sample of 73-years old men, the D12 and MDP had good psychometrical properties in terms of reliability and validity, which supports that the instruments are valid for use in population studies of older men.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12877-022-03166-5.