Qual Life Res (2014) 23:1279–1292 DOI 10.1007/s11136-013-0560-0
Validation of a Quality of Life Questionnaire for Bronchiectasis: psychometric analyses of the Spanish QOL-B-V3.0 Casilda Olveira • Gabriel Olveira • Francisco Espildora Rosa-Maria Giron • Gerard Mun˜oz • Alexandra L. Quittner • Miguel-Angel Martinez-Garcia
•
Accepted: 10 October 2013 / Published online: 19 October 2013 Ó Springer Science+Business Media Dordrecht 2013
Abstract Purpose Bronchiectasis is a chronic disease, leading to worsening of health-related quality of life. This study evaluated the psychometric properties of a new patientreported outcome for non-cystic fibrosis bronchiectasis, the Quality of Life Questionnaire Bronchiectasis, translated into Spanish (QOL-B-Sp-V3.0). Methods This prospective study recruited clinically stable patients with non-cystic fibrosis bronchiectasis at 4 Spanish centers. Health status was assessed with multiple indicators (dyspnea, exacerbations, bronchorrhea, etc.), microbiological,
This study is included in the PII of Bronchiectasis of SEPAR (Spanish Society of Pulmonology and Thoracic Surgery). Montserrat Vendrell (Universitary Hospital Dr Josep Trueta, Gerona, Spain) and Nuria Porras (Endocrinology and Nutrition Service, Carlos Haya University Hospital, Malaga, Spain) also participated in this study. C. Olveira (&) F. Espildora Pneumology Service, Hospital Regional Universitario de Ma´laga. IBIMA (Instituto de Investigacio´n Biome´dica de Ma´laga), Universidad de Ma´laga, Avenida Carlos Haya, 29010 Malaga, Spain e-mail:
[email protected] F. Espildora e-mail:
[email protected] G. Olveira Endocrinology and Nutrition Service, Hospital Regional Universitario de Ma´laga. IBIMA (Instituto de Investigacio´n Biome´dica de Ma´laga), Universidad de Ma´laga, Malaga, Spain e-mail:
[email protected] G. Olveira CIBERDEM, CIBER of Diabetes and Associated Metabolic Diseases (Instituto de Salud Carlos III), Madrid, Spain
radiological, spirometric, and anthropometric parameters plus St-George Respiratory Questionnaire (SGRQ). Psychometric analyses included internal consistency, test–retest reliability, convergent validity, predictive validity, and responsivity to change. Results The 207 stable patients (mean age 57.2 years) had a Bhalla score of 11.53 ± 7.39 and FEV1% of 68.3 ± 22.2 %. One hundred and sixty-one stable patients repeated the test 2 weeks later, and 80 patients who had an exacerbation within 6 months of the assessment also repeated it. Internal consistency was high across all scales (Cronbach’s alpha [0.70). Thirty-six of 37 items correlated more strongly with their assigned scale than a competing scale. Test–retest coefficients were strong (intraclass correlations r = 0.68–0.88). All scales, except Treatment Burden, discriminated significantly between patients with mild, moderate, and severe disease according to FEV1% and other respiratory parameters. Strong convergence was found between the QOL-B-Sp-V3.0 and SGRQ. Significant correlations were found between QOL-B-Sp-V3.0 and R.-M. Giron Pneumology Service, La Princesa Hospital, Madrid, Spain e-mail:
[email protected] G. Mun˜oz Pneumology Service, Idibgi, Hospital Universitari Dr Josep Trueta, Gerona, Spain e-mail:
[email protected] A. L. Quittner Department of Psychology, University of Miami, Coral Gables, FL, USA e-mail:
[email protected] M.-A. Martinez-Garcia Pneumology Service, Polytechnic and University La Fe Hospital, Valencia, Spain e-mail:
[email protected]
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various clinical, spirometric, radiological, and anthropometric variables. Significant differences were found on all QOL-B-SpV3.0 scales, except emotional functioning, between the baseline responses and onset of an exacerbation; robust sensitivity to change was observed on the Respiratory Symptoms scale. Conclusions The QOL-B-Sp-V3.0 questionnaire demonstrated strong reliability and validity. Scores were reproducible after 2 weeks, and it discriminated between patients who varied in severity and was responsive to changes related to exacerbation. Keywords Bronchiectasis Health-related quality of life Patient-reported outcome Forced spirometry volume in the first second Abbreviations BQ Bronchiectasis BMI Body mass index CDRQ Chronic Respiratory Disease Questionnaire CF Cystic fibrosis CFQ-R Cystic Fibrosis Questionnaire Revised FEV1 Forced spirometry volume in the first second HI Haemophilus influenzae HRCT High-resolution computed tomography HRQOL Health-related quality of life LCQ Leicester Cough Questionnaire MID Minimal important difference score MRC Medical Research Council PA Pseudomonas aeruginosa PRO Patient-reported outcome QOL-B-Sp Quality of Life Questionnaire for patients with Bronchiectasis. Spanish version SEPAR Spanish Society of Pulmonology and Thoracic Surgery SGRQ St. George Respiratory Questionnaire
Introduction Bronchiectasis (BQ) is a heterogeneous disease resulting from different causes, but managed in similar ways. It is chronic and leads to pulmonary exacerbations, loss of lung function, and worsening of health-related quality of life (HRQOL) [1, 2]. Care should be supervised by specialized units, at least in cases of chronic infection, recurrent exacerbations, or bronchiectasis with an etiology susceptible to specific therapy [1, 2]. Although pulmonary and nutritional outcomes are regularly monitored [1, 2], they are not strongly predictive of how patients function or feel in their daily lives [3–6]. The patient-reported outcome (PRO) is a direct measure of how a patient functions, feels, or survives in relation to his/her chronic illness [3, 5–10]. PROs are used to assess the patient’s perception of severity
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[3, 5–10] and may be used as primary or secondary outcome measures in drug registration trials [7, 11]. Several studies have found that patients with bronchiectasis report worse HRQOL than the general population, particularly patients with poor lung function, more frequent exacerbations, bronchorrhea, chronic infection with Pseudomonas aeruginosa (PA) [3, 9, 10, 12–14], and symptoms of depression and anxiety [4]. The St. George Respiratory Questionnaire (SGRQ) is the most widely used PRO for bronchiectasis, but is not specific for this disorder and has certain limitations, such as its length and variable recall [8– 10, 15, 16]. In addition, other PROs used in bronchiectasis, such as the Leicester Cough Questionnaire [17] (LCQ) and the Chronic Respiratory Disease Questionnaire (CDRQ) [18], are not designed specifically for this condition. Neither the LCQ nor the CDRQ includes a comprehensive list of respiratory symptoms, and the CRDQ requires an interviewer for administration. Finally, none of these PROs followed the instrument development guidelines published by the Food and Drug Administration [7]. Thus, there is a clear need for a disease-specific PRO for bronchiectasis. The purpose of the current study was to evaluate the psychometric properties of a new PRO for non-cystic fibrosis (CF) bronchiectasis (QOL-B) that includes assessment of respiratory symptoms and other domains of HRQOL. The QOL-B was developed in accordance with the FDA guidelines [7], beginning with a physician consensus panel, openended patient interviews, and cognitive testing, with several revisions made in response to patient data and feedback [19– 21]. Strong evidence of internal consistency, test–retest reliability, and convergent validity was found for the QOL-B in the USA [20]. This version has been translated into Spanish for use among Spanish speakers in the USA [2010, Quittner, Cruz, Kimberg, Marciel, and Barker QOL-B, Version 3.0. ‘‘Appendix’’], and our group has adapted it, with slight adaptations without changing the sense of the questions, to make it more suitable for Spain (QOL-B-Spain-V3.0). The transcultural validation of a HRQOL questionnaire that already exists in one language has the advantage of obviating the lengthy and tedious process of designing a new questionnaire. The aim of the present study was to validate this questionnaire in Spanish patients with non-CF bronchiectasis.
Patients and methods This prospective, multicenter sequential study included patients aged 16 and older who met the diagnostic criteria for bronchiectasis [1, 2] and attended a specific bronchiectasis unit at one of the four Spanish university hospitals for routine monitoring and treatment, over a recruitment period of 8 months. In all cases, bronchiectasis was diagnosed by high-resolution computed tomography (HRCT) of
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the chest, with the use of a 1–1.5-mm window every 10 mm and acquisition times of 1 s during full inspiration, following the criteria of Naidich et al. [22]. All patients had undergone a full etiological study following the diagnostic algorithm for bronchiectasis of the Spanish Society of Pulmonology and Thoracic Surgery (SEPAR) [1]. A full clinical history, from diagnosis to study participation, was recorded following the SEPAR protocol [1]. At each visit (every 2–3 months), demographic and clinical variables were collected prospectively. Patients performed spirometry were weighed and measured, and a sputum sample was collected and cultured for the usual bronchiectasis pathogens [1, 2]. The questionnaires were completed after a clinical examination to confirm that the patients were in a stable phase and before completing the clinical measures (including spirometry) and the various elective medical procedures in order not to bias responses. If at this time they had a respiratory exacerbation or a recent hospital admission, their participation was postponed for at least 60 days, until any acute illness was resolved. Patients were excluded if they had CF [23], if they had difficulty understanding the questionnaire, or if they refused to participate or sign the consent form. The study was approved by the Malaga Northeast Ethics and Research Committee, and all the participants provided written informed consent.
Clinical and demographic variables Data were gathered on demographic (age, sex), anthropometric (body mass index—BMI), clinical, and etiological aspects of bronchiectasis. The degree of dyspnea was recorded using the Medical Research Council (MRC) scale [24] and the comorbidity, with the Charlson index [25]. Spirometry was also performed, with the forced expiratory volume in 1 s (FEV1) expressed in absolute terms (mL) and as a percentage, using a reference population [26]. Structural damage was assessed with HRCT using the Bhalla scoring system (lower values indicate worse damage) at baseline or during the previous 12 months [27]. Assessment of the mean amount of sputum produced daily (in milliliters) was evaluated by instructing the patients to collect sputum during the 3 days prior to the visit in threegraded sterile containers (one per day), marking the amount reached each day on the container. Instructions were given to ensure that sputum was collected correctly, with low percentages of saliva recorded [12]. We analyzed chronic colonization by microorganisms, considering their appearance in sputum (at least 3 positive), regardless of their persistence at the time of the study [1]. Pulmonary exacerbations were assessed prospectively using the
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SEPAR criteria [1]. A mild–moderate exacerbation was defined as the acute development and persistence of changes in sputum characteristics (increased volume, thicker consistency, greater purulence, or hemoptysis), and/ or increased breathlessness unrelated to other causes, with or without other symptoms, and if they could be treated with oral antibiotics. An exacerbation was considered to be severe if intravenous antibiotics were necessary and there were tachypnea, acute respiratory failure, exacerbated chronic respiratory failure, a significant decline in oxygen saturation or respiratory function, hypercapnia, fever of more than 38 °C, hemodynamic instability, and/or impaired cognitive function [1]. The number of exacerbations and hemoptysis (whatever amount) in the year prior to the evaluation was also included in the analyses. Questionnaires QOL-B-Spain-V3.0 This is a disease-specific questionnaire for patients with bronchiectasis. It is a self-report measure consisting of 37 questions and takes about 10 min to complete. The scores are standardized across 8 scales, ranging from 0 to 100, with higher scores indicating better health-related quality of life. Strong evidence of internal consistency, test–retest reliability, and convergent validity was found for the QOL-B in the USA [19–21]. The Spanish version for Hispanic patients in the USA [2010, Quittner, Cruz, Kimberg, Marciel, and Barker QOL-B, Version 3.0. ‘‘Appendix’’] was adapted by us for use in Spain. This adaptation was initially administered to 20 patients to ensure complete understanding of all the items, after which slight changes in the Spanish were made without changing the sense of the questions. The SGRQ is a self-report health status measure, yielding three domain scores (symptoms, activity, and impact) and a total score. Scores range from 0 to 100, with higher scores representing worse health status [8]. The Spanish version has been validated for use in patients with bronchiectasis and been shown to be a valid instrument for analyzing health-related quality of life [9, 10]. Data analysis Data were analyzed with SPSS version 12 (SPSS-Inc, Chicago, IL). Quantitative variables were expressed as means ± standard deviations, with 95 % confidence intervals. Qualitative variables were compared using chi-square tests, with Fisher’s exact test where necessary. The normality of distributions was verified using the Kolmogorov– Smirnov test. For all variables, significance was set at p \ 0.05 for two tails.
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Validation design The following psychometric tests were conducted to evaluate the reliability and validity of the Spanish QOL-B-SpainV3.0: Reliability Reliability measures were of two types: 1. Internal consistency was evaluated using Cronbach’s alpha calculated for each scale and 2. Test–retest reliability (reproducibility): the QOL-B-Spain-V3.0 was administered twice to a subset of patients during stable visits, separated by a twoweek interval; intraclass correlation coefficients quantified reproducibility of scores over 2 weeks.
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difference between the two means of each scale (baseline and exacerbation) divided by the pooled standard deviation for those means. Effect size was interpreted as trivial (\0.2), small (0.2–0.5), moderate (0.5–0.8), and large ([0.8) following the guidelines proposed by Cohen [29]. To determine the minimal important difference score (MID) on the Respiratory Symptoms scale, which represents the smallest change a patient can detect, two distribution-based methods were used: (1) SD of the change on the Respiratory Symptoms scale (exacerbation score minus baseline score) and (2) one standard error of the mean (SEM) for the Respiratory Symptoms scale, calculated as pffiffiffiffiffiffiffiffiffiffiffiffiffiffiffi SEM ¼ SD ð1 aÞ [SD = SD of mean baseline QOL-B Spain V3.0 respiratory score; a = scale reliability] [30].
Construct validity Results Item-scale convergent and discriminant validity were examined by comparing the item-scale correlation. Convergent validity was supported if an item correlated (r C 0.4) with the scale it was hypothesized to belong to. Discriminant validity was supported whenever a correlation between an item and its hypothesized scale was higher than its correlation with the other components. Criterion validity Convergent validity: Spearman’s correlation coefficients were calculated for each QOL-B scale with the SGRQ domains and with demographic and health indicators, including age, FEV1 % predicted, number of exacerbations in the previous year, bronchiectasis severity as measured by the Bhalla score, daily bronchorrhea, dyspnea, Charlson morbidity index, and BMI. Discriminant (divergent) validity: to evaluate whether the QOL-B-Spain-V3.0 discriminates between patients who differ in disease severity based on lung function [26, 28] (FEV1% predicted), presence of hemoptysis during the past year, colonization by pathogens, and Bhalla scores (dichotomized based on the median of the sample- 13-). To compare scores between these groups, a Mann–Whitney nonparametric test or Student’s t test was used, depending on the normality of scores. To compare scores across three or more groups, we used an ANOVA or Kruskal–Wallis test. Responsiveness (sensitivity to change) In a subset of patients who experienced an exacerbation within 6 months of the baseline visit, comparisons of their scores prior to initiating treatment for the exacerbation were evaluated using the Student’s t test for paired data or Wilcoxon test, depending on normality. Effect sizes from baseline to exacerbation were also calculated as the
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A total of 218 patients were approached for the study and 207 agreed to participate. Of the 11 patients who were excluded, 3 had problems understanding the questionnaires and 8 declined participation. The mean age of the participants was 57.2 years (range 17–86) and 62.8 % were women. The mean Bhalla score was 11.53 (SD 7.39), and the mean FEV1% was 68.3 ± 22.2 % (range 15–123 %). Table 1 summarizes the clinical, spirometric, microbiological, radiological, and anthropometric characteristics of the sample. Two weeks after the baseline visit, the QOL-B-SpainV3.0 was administered a second time to 161 participants who were stable. In addition, to estimate the MID, 80 patients who experienced an exacerbation (all mild or moderate) within 6 months of the baseline visit also completed the QOL-B-Sp-V3.0, prior to starting treatment. The QOL-B-Sp-V3.0 showed strong internal consistency, as demonstrated by the strong Cronbach’s alpha coefficients (C0.70) on each scale (Table 2). Item to total correlations supported the content validity of the scales. Significant associations (r [ 0.40) were found between all items and their assigned versus competing scales (Table 3), except for Respiratory item 33 (Have you had shortness of breath with greater activity?), which correlated r = 0.66 on the Respiratory Symptoms scale and r = 0.70 with Physical Functioning. Floor effects were observed in \4 % and ceiling effects in\15 % of respondents on four of the eight scales. Test–retest reliability was also very strong, with a majority of ICCs above 0.70 for the scales, except Treatment Burden (0.68) (Table 2). Few gender differences were found in scores on the QOLB-Sp-V3.0: Emotional Functioning (women: 67.6 ± 25.5; men: 76.4 ± 24.5; p \ 0.05) and Treatment Burden (women: 63.6 ± 24.2; men: 72.3 ± 23.7; p \ 0.05).
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Table 1 Demographic and clinical characteristics Characteristics
Mean
SD
Age
57.2
18.1
n
(%)
\45 years
55
26.6
45–65 years
66
31.9
[65 years Males 2
Body mass index (Kg/m )
25.0
86
41.5
77
37.2
12
5.8
4.4
Undernourished (BMI \ 18.5 kg/m2) 2
Overweight (BMI: 25-30 kg/m )
63
Obese (BMI [ 30 kg/m2)
30
30.0 14.5
Smoking history Current smokers Ex-smokers
9 56
4.3 27.1
142
68.6
Idiopathic
58
28.0
Post-infection
80
38.6
Immunodeficiency
Non-smokers
Table 2 General description, internal consistency, and test–retest reliabilities of the QOL-B-Sp-V3.0 QOL-B-Sp-V3.0 scales
Items, no.
Cronbach a
ICC
Floor effect
Ceiling effect
Physical functioning
5
0.91
0.88
1.9
13.5
Role functioning
5
0.84
0.86
1.4
18.4
Vitality Emotional functioning
3 4
0.82 0.84
0.78 0.86
3.4 1.9
9.2 19.8
Social functioning
4
0.70
0.78
1.4
21.7
Treatment burden
3
0.72
0.68
1.7
16.6
Health perceptions
4
0.71
0.83
1.9
0.5
Respiratory symptoms
9
0.87
0.83
0.5
2.4
ICC intraclass correlation coefficient, QOL-B-Sp Quality of Life Questionnaire for patients with Bronchiectasis. Spanish version
Etiology
12
5.8
Collagen disease
7
3.4
Ciliary dyskinesia
22
10.6
28
13.5
68
32.9
64
30.9
Other Sputum production (ml/day)
21.8
25.6
FEV1% of predicted
68.3
22.2
Bhalla score
11.5
7.3
Chronic colonization P. aeruginosa H. influenzae Exacerbations in the last year Mild–moderate exacerbations Severe exacerbations
1.7 1.6
1.6 1.5
0.1
0.4
Bhalla score: based on high-resolution computed tomography (a lower score means more structural abnormalities) BMI body mass index. FEV1 forced expiratory volume in the first second
No significant differences were found in any scale between the baseline and the re-test questionnaires (Table 4). The QOL-B-Spain-V3.0 was also administered a second time to those who experienced an exacerbation to determine whether the instrument was responsive to these changes in health status. Significant differences were found between baseline scores and scores during a ‘‘sick’’ visit for an exacerbation (Table 4). On the Respiratory Symptoms, the mean difference was 17.6 ± 16.4 points (p \ 0.001), suggesting a major increase in symptoms with an exacerbation. Significant differences also existed in sputum volume (21.4 ± 28.2 vs. 49.5 ± 35.4 cc p \ 0.0001: mean difference: 28.1 ± 18.7). Significant associations were found between increased sputum volume and the reduction in the
Respiratory Symptoms score (r 0.34; p = 0.012). Effect sizes were trivial for Emotional Functioning, small for Physical Functioning, Social Functioning, and Treatment Burden, moderate for Role Functioning, Vitality, and Health Perceptions, and large for Respiratory Symptoms (Table 4). Using distribution-based methods to identify the MID, SD of the change in the Respiratory Symptoms score at baseline versus exacerbation was 8.2 points. The majority (70 %) of patients had a change in symptoms that was above the MID. Using one SEM, the MID was 6.8 points, indicating that most patients in exacerbation (71 %) were above the MID. Significant associations were found between all the QOL-B-Sp-V3.0 and SGRQ scores (Table 5). Significant positive associations existed between all QOL-B-Sp-V3.0 scores and FEV1%, except for Treatment Burden, and significant negative correlations for all QOL-B-Sp-V3.0 scores and dyspnea. Sputum volume correlated significantly and negatively with all QOL-B-Sp-V3.0 scales. Significant negative associations were found between BMI and QOLB-Sp-V3.0 scores for Physical Functioning, Vitality, Health Perceptions, and Respiratory Symptoms. Significant negative associations existed between age and each scale, except Social Functioning and Treatment Burden (Table 6). Figure 1 represents the mean QOL-B-Sp-V3.0 scores categorized by disease severity according to FEV1% [26, 28]. All the scores showed significant differences (worse HRQOL with greater severity) except for Treatment Burden. Figures 2 and 3 represent the results according to the Bhalla score, hemoptysis during the previous year, and colonization by Haemophilus influenzae (HI) and P. aeruginosa (PA). The Charlson index rose significantly according to age group (B45:1.38 ± 1 vs. 45–65:2.26 ± 1.4 vs. [ 65: 2.94 ± 2; p \ 0.001).
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Table 3 Item-scale correlations on the QOL-B QOL-B-Sp-V3.0 Items
Scales Physical
Role
Vitality
Emotion
Social
Treatment
Health
Respiratory
Physical 1
0.849**
0.635**
0.529**
0.468**
0.297**
0.250**
0.550**
0.510**
Physical 2
0.883**
0.692**
0.618**
0.590**
0.453**
0.264**
0.657**
0.639**
Physical 3
0.895**
0.666**
0.639**
0.555**
0.417**
0.292**
0.606**
0.587**
Physical 4
0.866**
0.601**
0.609**
0.524**
0.387**
0.264**
0.533**
0.617**
Health 5
0.566**
0.641**
0.654**
0.527**
0.343**
0.228**
0.741**
0.549**
Vitality 6
0.612**
0.623**
0.858**
0.573**
0.379**
0.197**
0.596**
0.564**
Emotional 7
0.427**
0.571**
0.470**
0.741**
0.384**
0.261**
0.511**
0.514**
Vitality 8
0.573**
0.505**
0.810**
0.475**
0.345**
0.327**
0.583**
0.497**
Vitality 9
0.631**
0.644**
0.867**
0.649**
0.461**
0.287**
0.624**
0.613**
Emotional 10
0.507**
0.598**
0.610**
0.869**
0.454**
0.282**
0.554**
0.478**
Emotional 11
0.522**
0.605**
0.550**
0.862**
0.445**
0.252**
0.581**
0.506**
Treatment 12
0.237**
0.301**
0.274**
0.287**
0.226**
0.866**
0.270**
0.305**
Treatment 13
0.293**
0.207*
0.187*
0.144
0.128
0.716**
0.163*
0.210**
Treatment 14
0.770
0.211**
0.171*
0.175*
0.291**
0.849**
0.231**
0.258**
Health 15
0.653**
0.664**
0.615**
0.606**
0.425**
0.305**
0.769**
0.632**
Physical 16
0.830**
0.664**
0.584**
0.547**
0.430**
0.234**
0.564**
0.553**
Role 17
0.660**
0.778**
0.558**
0.639**
0.461**
0.346**
0.611**
0.602**
Social 18
0.290**
0.372**
0.327**
0.395**
0.581**
0.207**
0.394**
0.371**
Social 19
0.408**
0.462**
0.402**
0.445**
0.634**
0.341**
0.350**
0.432**
Role 20
0.449**
0.745**
0.436**
0.461**
0.342**
0.208**
0.544**
0.504**
Health 21
0.308**
0.279**
0.245**
0.315**
0.425**
0.159*
0.631**
0.322**
Social 22
0.370**
0.425**
0.362**
0.411**
0.821**
0.166*
0.447**
0.498**
Emotional 23
0.543**
0.619**
0.486**
0.820**
0.569**
0.295**
0.523**
0.492**
Health 24
0.508**
0.624**
0.506**
0.536**
0.435**
0.248**
0.800**
0.518**
Role 25
0.541**
0.813**
0.462**
0.625**
0.457**
0.274**
0.562**
0.505**
Social 26
0.298**
0.370**
0.251**
0.358**
0.767**
0.165*
0.339**
0.342**
Role 27
0.695**
0.796**
0.600**
0.548**
0.402**
0.244**
0.601**
0.518**
Role 28
0.669**
0.803**
0.586**
0.561**
0.545**
0.250**
0.605**
0.597**
Respiratory 29
0.496**
0.519**
0.496**
0.441**
0.471**
0.351**
0.524**
0.784**
Respiratory 30
0.414**
0.440**
0.343**
0.365**
0.338**
0.209**
0.434**
0.731**
Respiratory 31
0.404**
0.481**
0.379**
0.430**
0.458**
0.282**
0.469**
0.763**
Respiratory 32
0.235**
0.250**
0.303**
0.208**
0.250**
0.224**
0.311**
0.509**
Respiratory 33
0.697**
0.650**
0.609**
0.578**
0.412**
0.231**
0.559**
0.657**
Respiratory 34
0.514**
0.456**
0.409**
0.395**
0.366**
0.171*
0.440**
0.753**
Respiratory 35
0.446**
0.482**
0.450**
0.470**
0.342**
0.275**
0.463**
0.612**
Respiratory 36
0.525**
0.462**
0.488**
0.447**
0.347**
0.148*
0.477**
0.559**
Respiratory 37
0.495**
0.516**
0.421**
0.444**
0.442**
0.221**
0.466**
0.773**
QOL-B-Sp Quality of Life Questionnaire for patients with Bronchiectasis. Spanish version The correlation is significant * p \ 0.05 (bilateral) and ** p \ 0.01 (bilateral)
Discussion This study demonstrated that the QOL-B-Sp-V3.0 is a reliable and valid PRO for patients with non-CF bronchiectasis in Spanish patients, and is sensitive to the effects of pulmonary exacerbations. These results are consistent with those of the English version of the QOL-B [19–21] and indicate that the Spanish version is conceptually equivalent to the original. In this Spanish version, evidence of good internal consistency was found across all scales, and it may
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therefore be used to compare groups. Furthermore, the scales Physical Functioning and Respiratory Symptoms could even be contemplated for individual comparisons. Similar strong internal consistency coefficients were also reported for the English language version [20]. Excellent item to total correlations were found across scales, supporting the underlying construct validity of these scales. Item 33 on the Respiratory Symptoms cross-loaded with the Physical Functioning scale. This reflects dyspnea upon exertion, and it is therefore reasonable that it should
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Table 4 Mean scores on the scales of the QOL-B-Sp-V3.0 QOL-B-Sp-V3.0 scales
Initial n = 207
Stable test–retest n = 161**
Mean ± SD
Baseline Mean ± SD
2 weeks Mean ± SD
Exacerbation n = 80 *** p
Baseline Mean ± SD
Exacerbation Mean ± SD
Effect size p
Physical functioning
57.5 ± 29.7
56.1 ± 29.3
56.6 ± 28.8
0.63
51.6 ± 29.1
38.4 ± 29.3
0.00*
0.45
Role functioning
70.4 ± 25.4
70.2 ± 25.6
68.5 ± 25.1
0.11
68.0 ± 25.8
51.1 ± 28.4
0.00*
0.62
Vitality Emotional functioning
57.6 ± 24.8 71.0 ± 25.4
56.9 ± 25.8 71.1 ± 25.6
59.0 ± 25.3 71.3 ± 24.1
0.12 0.88
54.4 ± 24.7 69.3 ± 27.4
39.4 ± 29.6 65.9 ± 26.0
0.00* 0.14
0.55 0.13
Social functioning
72.4 ± 25.1
71.8 ± 25.1
71.1 ± 24.6
0.58
68.9 ± 28.2
60.4 ± 29.0
0.00*
0.32 0.24
Treatment burden
67.1 ± 24.4
67.9 ± 23.1
66.4 ± 22.5
0.38
67.6 ± 24.8
61.8 ± 24.0
0.04*
Health perceptions
46.5 ± 21.6
46.1 ± 21.9
48.1 ± 22.8
0.06
43.0 ± 19.5
32.2 ± 22.4
0.00*
0.52
Respiratory symptoms
70.7 ± 19.7
71.0 ± 19.9
71.4 ± 19.2
0.65
69.9 ± 18.9
52.2 ± 21.3
0.00*
0.88
Stable Test–retest n = 161**: scores on the QOL-B-Spain-V3.0 at baseline and 2 weeks after the baseline visit in 161 patients (in a stable situation at both measurements) Exacerbation n = 80***: mean scores on the QOL-B-Spain-V3.0 at baseline and prior to starting treatment in 80 patients who experienced an exacerbation within 6 months of the baseline visit QOL-B-Sp Quality of Life Questionnaire for patients with Bronchiectasis. Spanish version * p \ 0.05 (Student’s t test for paired data or Wilcoxon test, depending on normality)
Table 5 Correlations between QOL-B-Sp-V3.0 scales and SGRQ QOL-B-Sp-V3.0 scales
SGRQ Symptom
Activity
Impact
Total
Physical functioning
-0.56**
-0.78**
-0.71**
-0.81**
Role functioning
-0.48**
-0.67**
-0.77**
-0.77** -0.67**
Vitality
-0.50**
-0.59**
-0.63**
Emotional functioning
-0.40**
-0.54**
-0.64**
-0.64**
Social functioning
-0.30**
-0.41**
-0.58**
-0.53**
Treatment burden
-0.24**
-0.23**
-0.37**
-0.34**
Health perceptions Respiratory symptoms
-0.43** -0.54**
-0.58** -0.57**
-0.70** -0.65**
-0.68** -0.69**
SGRQ St. George Respiratory Questionnaire (higher scores represent worse quality of life), QOL-B-Sp Quality of Life Questionnaire for patients with Bronchiectasis. Spanish version The correlation is significant ** p \ 0.01 (bilateral)
correlate adequately with the Physical Functioning scale. Additionally, across scales, minimal floor and ceiling effects were observed, enabling patients to report both improvement and worsening in their symptoms and daily functioning. Test–retest reliability over 2 weeks was strong, suggesting that patients’ scores are stable and reproducible [6, 31–33]. These values were similar to those found for the English language version [20]. We found good convergence between respiratory parameters and almost all scales on the QOL-B-Sp-V3.0. In all cases, higher scores correlated with better status, with bronchorrhea and degree of dyspnea demonstrating the
highest associations. Martı´nez-Garcı´a et al. [10, 12] and Chan et al. [14] also found that the patients with more severe dyspnea, bronchorrhea, and exacerbations had worse HRQOL on the SGRQ. Wilson et al. [34] reported similar results on the SGRQ in relation to exacerbations. Patients with the greatest structural damage on the HRCT had worse HRQOL on most scales. In the QOL-B English version, Respiratory Symptoms scores were also associated with HRCT scores [20, 21], and similar results were reported for the SGRQ [10, 12]. Analyses of microorganisms also supported the validity of the QOL-B-Spain-V3.0, for example, colonization by P. aeruginosa (PA) was associated with worse scores across most of the scales. Other authors also found a worse HRQOL (SGRQ) in patients with chronic colonization by P. aeruginosa [10, 12, 13]. Convergent validity was also demonstrated by the significant correlations found between all dimensions of the QOL-B-Sp-V3.0 and the SGRQ [8–10], reaching very high values in scales measuring similar parameters, as occurred with the QOL-B English version [20]. The instrument demonstrated good discrimination of disease severity in relation to FEV1% for all scales except Treatment Burden, the strongest associations being for Respiratory Symptoms and Physical Functioning. A similar pattern of results was found for the Cystic Fibrosis Questionnaire Revised [6] (CFQ-R) and its relationship to spirometry but lack of association between disease severity and Treatment Burden [5, 6]. The lack of a correlation with this scale may be because it is of a conditional type and it has a long heading, as it contains various types of therapy
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Table 6 Correlations between QOL-B-Sp-V3.0 and health status variables QOL-B-SpV3.0 scales
Age
FEV1% predicted
Charlson comorbidity index
Bhalla score
Mild exacerbation
Severe exacerbation
Sputum production (ml/day)
MRC dyspnea scale
BMI
Physical functioning
-0.45**
0.41**
-0.19**
0.33**
-0.19**
-0.21**
-0.20**
-0.60**
-0.23**
Role functioning
-0.34**
0.29**
-0.18**
0.35**
-0.19**
-0.25**
-0.26**
-0.58**
-0.13
Vitality
-0.31**
0.29**
-0.16*
0.30**
-0.22**
-0.19**
-0.25**
-0.45**
-0.17*
Emotional functioning
-0.27**
0.19**
-0.17*
0.16
-0.11
-0.20**
-0.20**
-0.44**
-0.10
Social functioning
-0.11
0.14*
-0.03
0.24
-0.07
-0.07
-0.30**
-0.25**
-0.00
Treatment burden
-0.08
0.11
-0.04
0.23*
-0.24**
-0.16*
-0.18*
-0.19**
0.047
Health perceptions
-0.26**
0.29**
-0.18**
0.24*
-0.23**
-0.18**
-0.27**
-0.44**
-0.18**
Respiratory symptoms
-0.28**
0.34**
-0.06
0.45**
-0.18**
-0.25**
-0.48**
-0.48**
-0.15*
Bhalla score: based on high-resolution computed tomography (a lower score means more structural abnormalities) QOL-B-Sp Quality of Life Questionnaire for patients with Bronchiectasis. Spanish version, FEV1 forced expiratory volume in the first second, MRC Medical Research Council, BMI body mass index The correlation is significant * p \ 0.05 (bilateral) and ** p \ 0.01 (bilateral)
Fig. 1 Scores on the QOL-BSp-V3.0 questionnaire according to forced expiratory volume in one second, as a percentage of the predicted volume (FEV1 %). QOL-B-Sp Quality of Life Questionnaire for patients with Bronchiectasis. Spanish version. **p \ 0.01; *p \ 0.05
used for bronchiectasis, which could lead to poor understanding, particularly for older persons. Some authors found a good capacity to differentiate the severity according to the FEV1% with the SGRQ [10, 12, 14], though others noted its poor associations with the functional variables [34]. A stronger association was found between age and QOLB-Sp-V3.0 scores. Older patients reported worse HRQOL across all scales except two. In contrast, the QOL-B English version [20] found no differences by age, though the mean
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age of this sample was 63 years versus a mean of 57.2 and a wide age range (17-86 years) in the Spanish sample. Older age also confers a higher probability of having other comorbidities, which can affect HRQOL [9]. This was seen in our study in which the Charlson index was significantly higher in older patients and correlated negatively with Health Perceptions, Physical, Role, and Emotional Functioning scales. Although our questionnaire does not specifically evaluate dimensions related to nutritional status, we found
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Fig. 2 a Scores on the QOL-BSp-V3.0 questionnaire according to the Bhalla score (scoring system based on computerized tomography of the chest). QOL-B-Sp Quality of Life Questionnaire for patients with Bronchiectasis. Spanish version. **p \ 0.01; *p \ 0.05. b Scores on the QOL-B-SpV3.0 questionnaire according to whether the patients had hemoptysis during the previous year. QOL-B-Sp Quality of Life Questionnaire for patients with Bronchiectasis. Spanish version. **p \ 0.01; *p \ 0.05
significant negative correlations with the BMI (higher BMI, worse HRQOL) in several domains. Obesity and overweight condition a worse HRQOL in general and obesity, particularly, can lead to worse mobility and respiratory difficulty. Malnutrition is also associated with a worse HRQOL [35]. The present study recruited very few patients who were undernourished according to their BMI (only 5.8 % had a BMI \18.5 kg/m2), though 44.5 % were either overweight or obese. In any case, it would have been better to use a more precise measure of body composition, for instance fat-free mass index, as this is a better predictor of morbidity and mortality and is associated with a worse lung function and its associated inflammation in patients with bronchiectasis [35–37]. This index is associated with a worse HRQOL in adult CF patients (using the CFQ-R) in domains not directly related
to nutrition, as are Physical Functioning, Vitality, and Respiratory Symptoms [5]. Finally, a PRO must demonstrate that it is responsive to changes in health status that reflect the course of the disease (e.g., exacerbations) or the use of new treatment. We found significant differences between patients’ scores in a stable vs. exacerbation state on each scale except Emotional Functioning. This seems logical as this scale measures the presence of symptoms of depression and/or anxiety, which is usually related more with the number of exacerbations in the last year [1, 2] than with the presence of exacerbations in the short term. Most importantly, substantial changes were documented on the Respiratory Symptoms scale, which were greater than the MID, even though all the exacerbations were mild or moderate and only needed oral antibiotics. Likewise, the effect size for this scale was also large.
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Fig. 3 a Scores on the QOL-BSp-V3.0 questionnaire according to whether the patients had chronic bronchial colonization by P. aeruginosa. QOL-B-Sp Quality of Life Questionnaire for patients with Bronchiectasis. Spanish version. **p \ 0.01; *p \ 0.05. b Scores on the QOL-B-SpV3.0 questionnaire according to whether the patients had chronic bronchial colonization by H. influenzae. QOL-B-Sp Quality of Life Questionnaire for patients with Bronchiectasis. Spanish version. **p \ 0.01; *p \ 0.05
Further, one of the hallmark symptoms of an exacerbation in this population is increased mucous production [1, 2], which in fact increased markedly during the exacerbation period and correlated with the reduction in the score on the Respiratory Symptoms scale. Similar MID values based on distribution methods have been found in Spain (8.2 using SD of the change and 6.8 using one SEM) and the USA (8.08) [21]; both values triangulate well with the anchorbased value derived from patient assessments of 9.0. Accordingly, for the Respiratory Symptoms scale, we propose that 8 is a suitable cutoff for the MID. The strengths of this study include its multicenter design, large number of patients, analysis of several different variables, and detailed psychometric analyses. One
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limitation was the application of only distribution-based methods to determine the MID. A future study should reevaluate the MID using anchor-based methods, which more closely reflect the patient’s perspective.
Conclusions The QOL-B-Sp-V3.0 demonstrated its reliability, validity, and responsivity in a large, diverse group of Spanish patients with non-CF bronchiectasis. Acknowledgments PAR (31/2011).
This study was supported by a grant from SE-
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Appendix
CUESTIONARIO SOBRE CALIDAD DE VIDA – BRONQUIECTASIAS Comprender los efectos de su enfermedad y su tratamiento en su vida diaria, puede ayudar a su médico a controlar su salud y ajustar sus tratamientos. Por este motivo, hemos desarrollado un cuestionario sobre calidad de vida específico para las personas que tienen bronquiectasias. Gracias por acceder a rellenar este cuestionario. Instrucciones: Las siguientes preguntas se refieren a como percibe usted su estado actual de salud. Esta información nos permitirá comprender mejor cómo se siente en su vida diaria. Le rogamos que responda a todas las preguntas. No hay respuestas correctas o incorrectas. Si no está seguro de cómo responder, elija la respuesta que más se adecúe a su situación.
Apartado I. Calidad de vida
Marque la casilla que corresponda a su respuesta. Mucha dificultad
Dificultad moderada
Poca dificultad
Ninguna dificultad
Siempre
A menudo
Algunas veces
Nunca
Durante los últimos 7 días, en qué medida ha tenido dificultad para: 1. Realizar actividades que requieren esfuerzo como, por ejemplo, trabajos de jardinería o ejercicio físico. 2. Caminar al mismo ritmo que otras personas (familiares, amigos, etc.). 3. Transportar objetos pesados como, por ejemplo, libros o bolsas de la compra. 4. Subir un tramo de escaleras.
Durante los últimos 7 días, indique con qué frecuencia: 5. Se ha sentido bien. 6. Se ha sentido cansado/a. 7. Se ha sentido inquieto/a. 8. Se ha sentido con energía. 9. Se ha sentido agotado/a. 10. Se ha sentido triste. 11. Se ha sentido deprimido/a.
¿Está actualmente bajo algún tratamiento para las bronquiectasias (por ejemplo, utiliza medicación oral o inhalada , nebulizadores como Pari® I-neb® o E-flow rapid®, fisioterapia respiratoria, dispositivos PEP o Flutter®, o bien el sistema The Vest®o ventilación mecánica no invasiva) ? Sí
No (vaya a la pregunta 15, al final de la página)
Marque con un círculo el número que corresponda a su respuesta. Elija sólo una respuesta para cada pregunta. 12. ¿En qué medida los tratamientos para las bronquiectasias hacen su vida diaria más difícil? 1. Nada en absoluto 2. Un poco 3. Moderadamente 4. Mucho
13. En la actualidad, ¿cuánto tiempo dedica diariamente a los tratamientos para las bronquiectasias? 1. Mucho 2. Una cantidad moderada 3. Un poco 4. Casi no le dedico tiempo
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Qual Life Res (2014) 23:1279–1292 14. ¿Cuánto le cuesta conciliar los tratamientos para las bronquiectasias con su vida diaria? 1. No me cuesta en absoluto 2. Un poco 3. Moderadamente 4. Mucho
Marque con un círculo el número que corresponda a su respuesta. Elija sólo una respuesta. 15. ¿Cuál cree que es su estado de salud actual? 1. Excelente 2. Bueno 3. Regular 4. Malo
Marque la casilla que corresponda a su respuesta. Teniendo en cuenta su estado de salud durante los últimos 7 días, indique en qué medida es cierta para usted cada afirmación.
Totalmente cierta
Cierta en su mayor parte
Un poco cierta
Nada cierta
16. Debo limitar las actividades que requieren esfuerzo como, por ejemplo, caminar o practicar ejercicio físico. 17. Debo quedarme en casa más de lo que me gustaría. 18. Me preocupa verme expuesto a otras personas que estén enfermas. 19. Me resulta difícil intimar con la pareja (besos, abrazos, etc.). 20. Llevo una vida normal. 21. Me preocupa que mi salud empeore. 22. Creo que mi tos molesta a los demás. 23. A menudo me siento solo/a. 24. Me siento sano/a. 25. Resulta difícil realizar planes para el futuro (vacaciones, asistir a acontecimientos familiares, etc.). 26. Me da vergüenza cuando toso.
Marque con un círculo el número o bien marque la casilla que corresponda a su respuesta. Durante los últimos 7 días: 27. ¿En qué medida tuvo problemas para seguir el ritmo de su trabajo, tareas del hogar u otras actividades cotidianas? 1. No tuvo problemas para seguir el ritmo. 2. Se las arregló para seguir el ritmo pero con alguna dificultad. 3. Realizó las actividades con retraso. 4. No pudo realizar estas actividades.
Siempre
A menudo
Algunas veces
Nunca
28. ¿Con qué frecuencia interfiere el hecho de tener bronquiectasias con realizar sus metas de trabajo, del hogar, de la familia o personales?
Apartado II. Síntomas respiratorios
Marque la casilla que corresponda a su respuesta.
Indique cómo se ha sentido durante los últimos 7 días: 29. ¿Ha notado congestión en el pecho? 30. ¿Ha tosido por el día? 31. ¿Ha expulsado mucosidad al toser?
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Mucho
Una cantidad moderada
Un poco
Nada en absoluto
Qual Life Res (2014) 23:1279–1292 32. Sus esputos han sido mayoritariamente:
1291 Transparentes
Entre transparentes y amarillos
Entre amarillentos y verdes
Entre parduzcos y marrones oscuros
Verdes con trazas de sangre
No lo sé.
Cantidad de esputo total en un día estando agudizado (MAL):
cc
Con qué frecuencia durante los últimos 7 días:
Siempre
A menudo
Algunas veces
Nunca
33. ¿Le ha faltado la respiración al realizar una mayor actividad como, por ejemplo, tareas del hogar o de jardinería? 34. ¿Ha experimentado silbidos (pitos)? 35. ¿Ha experimentado dolor en el pecho? 36. ¿Le ha faltado la respiración mientras hablaba? 37. ¿La tos le ha despertado durante la noche?
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