Background
Pneumoconiosis is an occupational disease of the lungs caused by inhaling organic or non-organic dust retained in the lungs [
1,
2]. Patients with pneumoconiosis typically suffer from reduced lung functions [
3‐
5], different mood and respiratory symptoms [
6], and decreased tolerance for physical exercise [
5]. Together, they contribute towards the deterioration of health-related quality of life (HRQOL) [
4,
7]. Patients with chronic obstructive pulmonary diseases (COPD), including pneumoconiosis, are frequently referred to pulmonary rehabilitation (PR) programmes [
8]. These programmes aim to relieve symptoms and to improve capacity for exercise, emotional function, sense of control, and HRQOL [
8]. The content and settings of different PR programmes, their model of delivery, and personnel involved in the delivery may vary according to local health care systems and resources [
9,
10]. Most PR programmes for COPD patients include either low or high-intensity exercise training, endurance-training and strength training [
9‐
11]. Apart from rehabilitating the physical aspect of patients, these programmes may include health education, psychosocial support, and/or nutritional counseling [
10,
11]. The common settings in which PR programmes are delivered include hospital-based [
12], community-based [
4,
13], or patient’s home [
14‐
18]. Different settings cater for the different needs of the patients. The common duration of PR programme is 8 weeks [
19]. A recent meta-analysis reviewed 65 studies on PR programmes. It was reported that PR programmes led to significant benefits in relieving dyspnoea and fatigue, and on improving exercise capacity and HRQOL, among COPD patients [
8].
In Hong Kong, PR services for patients with pneumoconiosis were funded by the Pneumoconiosis Compensation Fund Board. It is a statutory body established by the local government. Three public hospitals and 2 nongovernmental organisations (NGOs) were responsible for conducting PR services [
1,
20]. PR services included two core programmes: Community-Based Rehabilitation Programme (CBRP) and Home-Based Rehabilitation Programme (HBRP).
CBRP was the standard programme consisting of protocol-based classes delivered by healthcare professionals at community centres. Typical classes include breathing re-training, exercise re-conditioning, health education, teaching energy conservation techniques and panic control skills (see Additional file
1). The duration was four to 6 weeks with a frequency of twice per week.
HBRP was designed to cater for patients unable to access community-based services due to profound incapacities. The content of the programme was customised according to the needs of the patients during home visits. Unlike the typical PR services offered by CBRP, HBRP provided additional psychological support to the patients and their family. Examples of tailored services included home modification, carer-training, and living skills-training (see Additional file
1). HBRP was delivered by healthcare professionals offering eight home visits, each lasting at least 1 hour. CBRP and HBRP were complemented by adjunctive programmes that helped pneumoconiosis patients better manage their illnesses. Detailed description of each of the programmes as aforementioned can be found in the Additional file
1.
Several systematic reviews have reported positive effects of PR programmes on patients with COPD. They include minimizing COPD symptoms, improving exercise capacities, as well as improving health-related quality of life [
8,
21‐
25]. Previous studies as well as expert opinions have consistently shown that PR programmes did not bring about improvement in the lung functions of patients with COPD [
23‐
26]. Nevertheless, lung function had been identified as an important factor influencing HRQOL in pneumoconiosis patients [
4]. It is worthwhile to explore whether the physical and psychological benefits brought about by the PR [
8,
21,
22] are independent of the patients’ initial lung functions. Ascertaining this is essential for a greater understanding of the precise benefits of PR programmes for patients with pneumoconiosis.
Moreover, the majority of previous studies had not recruited pneumoconiosis patients. This calls for an investigation on the effect of PR programmes on patients who suffered from pneumoconiosis. This study aims to examine the outcomes of both the CBRP and HBRP for pneumoconiosis patients based on archived data from 2008 to 2011 by the Hong Kong Hospital Authority. Moreover, we performed covariance analyses to examine the outcomes of CBRP and HBRP independent from patients’ baseline lung functions. The relationships among patients’ characteristics, types of program participations, and clinical outcomes were examined. The findings will pave the way for contents of future PR programmes to be enhanced for pneumoconiosis patients.
Discussion
To our knowledge, this study is the first to report the outcomes of community-based and home-based pulmonary rehabilitation programmes provided by the same teams of rehabilitation professionals from three separate hospitals. Therefore, the treatment outcomes of the two types of programmes are very comparable. This reveals specific strengths and weaknesses associated with each programme. This is also the first report of pulmonary rehabilitation treatment outcomes independent of patients’ baseline lung functions, particularly regarding the importance of patients’ participation in influencing the physical and psycho-social aspects of the treatment outcomes on pneumoconiosis patients.
The results suggested that the CBRP had positive effects in enhancing the patients’ HRQOL (CRQ fatigue, emotion, and mastery) and reducing their psychological symptoms (HADS anxiety and depression). Patients who participated in the CBRP were found to show improvement in their knowledge about the disease as well as the exercise capacity (6MWT). The findings on the improvement in the patients’ quality of life are consistent with those of previous studies [
13,
31]. However, the finding that the CBRP did not improve the CRQ dyspnoea score is inconsistent with findings reported in previous studies [
32,
33]. A plausible reason for this discrepancy is that this study incorporated patients’ baseline lung function as a covariate, which was not the case in previous studies. Future studies should further explore how a patient’s lung function, particularly different levels of initial lung capacities, would influence the treatment outcomes of PR programmes.
Several studies proposed that social support [
31,
34‐
36] embedded in community-based PR programmes contributes towards the improvement in patient’s psychological symptoms [
31,
36,
37]. The results of this study further substantiate this proposition. A higher number of home visits (CHCP) made to the patients, as well as their relatives having attended educational talks more frequently (in HLP) were factors found to be significantly associated with the reduction of depression symptoms among patients who completed the CBRP. The CHCP consisted of home visits by healthcare professionals to monitor the health and psycho-social statuses of patients (see content in Additional file
1). The HLP involved educational talks to patients and their relatives on self-maintenance and healthy lifestyles. The RHP provided lectures on pneumoconiosis and respiratory hygiene. Open to both patients and their relatives, the talks were arranged by NGOs but conducted by healthcare professionals. These classes were useful for enhancing patient’s knowledge on the disease. This postulation is supported by findings on the significant relationships among the relatives’ participation in the CBRP and RHP and patient’s gain in the knowledge (Fig.
1b).
Apart from learning about the disease, the patients showed improvements in mobility function after participating in the CBRP. A mean improvement of 59.5 m in 6MWT was found to exceed the clinical threshold of 54 m set in other studies [
38,
39]. Our findings on mobility, as general exercise capability, are consistent with those reported in other studies on community-based programmes, which considered mobility as an important outcome to patients with pneumoconiosis [
13,
33].
In general, the effects of the HBRP were more modest than those of the CBRP. After controlling for patients’ baseline lung capacities, significant improvements were found in patients’ knowledge about the disease and in exercise capacity after completing the HBRP. The improvements in exercise capacity after completing the HBRP were consistent with previous findings [
14,
15,
17,
40]. Patients who completed the HBRP showed a mean increase of 47.6 m on the 6MWT, which is below the clinical threshold of improvements suggested in other studies [
38,
39]. This is perhaps because patients in the HBRP were of older age, had greater baseline %DOIs, and lower lung capacities than those in the CBRP. Of note, the HBRP did not appear to produce significant positive effects in improving patients’ health-related quality of life and psychological symptoms. These findings are inconsistent with those reported in previous studies on home-based programmes [
14,
15,
40,
41]. This inconsistency could have been due to the small sample size of the HBRP group. Previous studies indicated that patients of home-based programmes valued social support from and interactions with professionals, families, and peers [
42‐
44]. A recent study suggested that home-based programmes should aim at improving physical capacities in order for patients to progress and participate in community-based programmes, which bring stronger psychosocial benefits [
17].
The improvement of the 6MWT in HBRP patients was related to the total number of programmes of HBRP and RHP that the patients had participated in (Table
4c and Fig.
1c). Pulmonary rehabilitation consists of many programmes that help improve patients’ physical functions (Additional file
1). It is likely for patients who had participated in more PR programmes to gain more benefits, thus performing better in the 6MWT. The HBRP involved physical and respiratory training, which improved patients’ exercise tolerance levels [
14]. A longer training period was found to be more effective in enhancing the physical functions [
31]. In the RHP, therapists taught patients about pneumoconiosis, respiratory hygiene, the use of inhalers, and energy conservation. These resulted in better health management [
45] and the ability to achieve greater exercise tolerance levels for those who participated more frequently.
Limitations
The data obtained for this study was based on convenient sampling, hence, the findings should be interpreted with caution. Generalization of results to other groups of patients with pneumoconiosis would therefore be limited. The study was not a randomized controlled trial. Thus, the treatment effects reported showed, at best, trends in improvements.
No information on the medications taken by the patients was included in the data. Nevertheless, the common practices of all the case medical officers who referred the patients for enrolment in the community- or home-based rehabilitation programmes were: 1) patient was referred when the medications were deemed optimized for the symptom control; and 2) the medications typically prescribed to the patients included various types of inhaled bronchodilators. Despite taking a relatively unified approach to the medication prescriptions, the possibility that the differences in the outcomes among the patients between the two programmes due to the differences in the medications taken by the patients cannot be completely excluded.
Another drawback is that the patients’ data was under-reported. This is rather common in studying outcomes of pulmonary rehabilitation among patients with COPD [
14,
46]. The 181 completed cases out of the 685 total cases may not fully represent the typical patients receiving the services. Many of the patients had repeatedly participated in the CBRP or HBRP, so the treatment effects could have been inflated. Further studies should generate evidence on the efficacy of these programmes by employing a more stringent research design and larger sample size.
Conclusion
Patients with pneumoconiosis require long-term rehabilitation services. To best fulfil their needs, rehabilitation programmes are offered in the community or at home. The patients were found to show positive gains in areas of knowledge, exercise tolerance, quality of life, and psychological symptoms after attending community-based programmes. Some of these gains were related to patients’ attendance frequency levels of adjunctive programs and the involvement levels of their relatives in the treatment processes. Home-based programmes, in contrast, produced less obvious treatment effects, particularly regarding quality of life and psychological symptoms. The findings suggest the importance of strengthening psycho-social intervention for patients who take part in home-based rehabilitation programmes.