Figures
- FIGURE 1
a) Connectogram. Measures are plotted as a wheel with connections between each measure input to the model shown as a thread. The thickness of the thread provides a visual representation of the strength of the relationship between any two measures (R≥0.35). Coloured dots highlight the common factors underlying groups of measures. Pink dots correspond to Factor 2 (affect/mood), red to Factor 1 (body burden), blue to Factor 3 (breathing burden) and orange to Factor 4 (anger/frustration). b) Factor diagram. The retained measures are shown on the left hand side of the diagram while the contribution of each measure to the resulting factor is shown as a loading weight (rectangular boxes) Factors are shown as ovals with descriptive labels underneath. The covariance across factors is illustrated by the curved lines.
- FIGURE 2
Clustergram. A matrix of each participants score across the four factors. Factor score is measured in arbitrary units (au). Each of the four factors is displayed along the bottom, with participants forming the y-axis. Factors 1 and 3 correspond to body and breathing burden, while Factors 2 and 4 correspond to affect/mood and anger/frustration. A dendrogram is displayed along the left side and highlights the division of participants into the two groups, higher symptom burden and lower symptom burden.
- FIGURE 3
The relative proportion of each disease category belonging to the higher and lower symptom burden groups shown. Each participant is represented by a single square. Colours encode disease category as follows. Red: idiopathic pulmonary fibrosis; orange: other interstitial lung disease; yellow: COPD; blue: asthma; purple: heart failure; and pink: “other” (including depression, cancer, diabetes and renal failure).
- FIGURE 4
Factor diagram. A compact factor model in which low loading measures were sequentially removed. The retained measures are shown on the left-hand side of the diagram with the contribution of each measure to the resulting factor shown as a loading weight (rectangular boxes). Removed measures are shown in shaded boxes next to the factor to which they previously belonged. Factors are shown as ovals with descriptive labels underneath. The covariance across factors is illustrated by the curved lines.
Tables
- TABLE 1
Demographic information per main cause of breathlessness (total subjects=182)
Main cause of breathlessness Attended at baseline Age years Female BMI kg·m−2 COPD 45 (24.7%) 71.6±9.2 29 26.6±7.8 Asthma 39 (21.4%) 53.2±15.2 29 27.9±5.3 Heart failure 35 (19.2%) 76.4±7.9 8 30.5±5.7 IPF 34 (18.7%) 75.1±6.8 16 25.9±3.9 Other ILD 5 (2.7%) 69.3±11.7 2 28.4±4.5 Other diagnoses# 24 (13.2%) 66.4±14.6 13 25.9±6.7 Number of patients with 1/2/3/4 comorbidities 50/16/4/1 Comorbidity frequency by diagnosis COPD Diabetes n=30; heart failure n=10; other breathlessness n=7; asthma n=5; cancer n=4; renal failure n=2 Asthma Diabetes n=8; other breathlessness n=2; ILD n=2 Heart failure Diabetes n=13; renal failure n=8; COPD n=4; other breathlessness n=2; asthma n=2; cancer n=2 IPF Diabetes n=5; renal failure n=2; other breathlessness n=2; heart failure n=1; asthma n=1 Other ILD Diabetes n=2; COPD n=1; heart failure n=1 Other diagnoses# Heart failure n=5; diabetes n=5; asthma n=3; renal failure n=2; cancer n=1; COPD n=1 Data are presented as mean±sd, n (%) or n. IPF: idiopathic pulmonary fibrosis; ILD: interstitial lung disease; BMI: body mass index. #: other diagnoses include depression, cancer, diabetes and renal failure.
- TABLE 2
A list of measures included in the exploratory factor analysis model
1. Sex 14. mMRC 2. Age 15. EQ-5D-5L – Index 3. BMI 16. FACIT – Fatigue Scale 4. Dyspnea-12 – Affect 17. Average severity of pain 5. Dyspnea-12 – Physical 18. CAT 6. MDP_A2_Anxiety 19. MDP_A2_Depression 7. MDP_A2_Afraid 20. MDP_A1_Breathing Discomfort 8. MDP_A2_Angry 21. MDP_SQ1_Physical Effort 9. MDP_A2_Frustrated 22. MDP_SQ2_Hunger 10. Breathlessness at rest 23. MDP_SQ3_Tightness 11. Breathlessness mean 24. MDP_SQ4_Mental Effort 12. HADS – Depression 25. MDP_SQ5_Hypernoea 13. HADS – Anxiety BMI: body mass index; MDP: multidimensional dyspnea profile; SQ: sensory dimension; A2: emotional response domain; HADS: hospital anxiety and depression scale; FACIT: functional assessment of chronic illness therapy – fatigue scale; mMRC: modified Medical Research Council breathlessness scale; CAT: COPD assessment test; EQ-5D–5L: EuroQol five dimensions – five levels.
