The dread of movement in COPD patients owing to dyspnea has been increasingly recognized by researchers, and current research focuses on the creation of measuring techniques[4], the analysis of influencing variables, and the assessment of the present situation[39, 40]. Intervention studies comprised endurance training[41, 42], inspiratory muscle training[14], and cognitive modification[33, 43]. However, we discovered that a single exercise training was unable to increase patients' exercise efficacy and that a single cognitive modification had a limited effect. We created a combined intervention based on the fear-avoidance model and social cognitive theory (SCT) to increase the efficacy of the treatment for patients. To alleviate dyspnea-related kinesiophobia in patients with moderate to severe COPD, we utilized the catastrophic cognition of dyspnea in COPD patients as the entry point of the study, incorporated cognitive changes into the study design of exercise training, developed an intervention protocol using evidence-based constructs and expert correspondence, and validated its efficacy.
Patients with moderate to severe COPD in our research all reported a high level of dyspnea-related kinesiophobia. The control group's BBQ score was (33.62 ± 3.16), while the intervention group's BBQ score was (34.73 ± 3.64), which matched the cross-sectional survey results of domestic scholars[44–46]. After an 8-week intervention, the intervention group's BBQ, BBQ-SF, and BBQ-AA scores were significantly lower than the control group's, and the differences were statistically significant (P<0.05), indicating that cognitive combined exercise intervention was more effective than routine nursing in improving dyspnea-related kinesiophobia in patients with moderate to severe COPD, which was consistent with the expected effect reported in the literature[45, 47]. It is possible that patients with limited illness cognition are more prone to dyspnea anticipatory anxiety, and the body recalls the inciting circumstances that worsen dyspnea and causes avoidance behavior when the inducing events are met again[30]. This anticipatory worry may exacerbate the individual's sickness experience and possibly contribute to cognitive errors. This study's intervention approach centered on developing patients' proper illness cognition. We enhanced self-efficacy, decreased anxiety, acknowledged the reality of dyspnea symptoms, and corrected the incorrect belief that exercise exacerbated the condition by delivering propaganda films and manuals every week. It is also possible that the active cycle of breathing technique (ACBT) focuses on the exercise of inspiratory muscle function, allowing the patient's external intercostal muscles to retain their remodeling ability after a short loading period, and only produce specific functional and structural effects on the trained muscles (inspiratory muscles). Following training, the percentage of type I and type II fibers in the external intercostal muscles rose dramatically, enhancing inspiratory muscular strength and endurance, alleviating dyspnea symptoms[48], and improving kinesiophobia. Furthermore, training in front of a mirror might boost patient interest in the exercise procedure and may impact the intervention result. This visual stimulus[49], which creates an illusion by using a mirror, is primarily governed by inconsistency of partial sensory and motor information, delivering corrective sensory input and finally restoring its consistency. Patients' anxiety and dread of exercise may be lessened due to the integration of sensation and movement in the central nervous system[50, 51]. As a result of the visual stimulation, COPD patients in this research may manage their dyspnea and discomfort, reduce kinesiophobia symptoms, and enhance their belief in breathing exercise.
The intervention group's synergistic impact was still evident at the 12th week. Although the BBQ, BBQ-SF, and BBQ-AA scores declined slowly compared to the 4th and 8th week, the difference between the two groups was statistically significant (P<0.05), indicating that the intervention had a good continuous impact and that the influence remained after the intervention ended. Exercise training for patients with dyspnea has been found in studies to lower the degree of anxiety and panic associated with dyspnea most significantly during the eighth week of intervention, with the impact remaining significant for 6 months[52], which is consistent with the findings of our study. According to the literature, cognitive intervention is a long-term process that requires at least 6 weeks of proper fitness training mixed with cognitive intervention[6, 53]. Saka S also determined that 8 weeks of inspiratory muscle training might greatly reduce kinesiophobia[14]. However, in this research, the scores of BBQ, BBQ-SF, and BBQ-AA reduced after 4 weeks of intervention, and the change was statistically significant. It is possible that the combined intervention influenced the entire program, or that the severity of the patients' condition changed the time to effect of the intervention.
The pulmonary function test is very important in the diagnosis of COPD. After 8 weeks of intervention, FVC and FEV1 were significantly greater than in the control group. The control group had greater FEV1% and FEV1/FVC, although the difference was not statistically significant. The majority of research have shown that inspiratory muscle training may enhance lung function, however the benefits of exercise vary among investigations[14, 54]. It might be because the recruited patients had varying degrees of illness, resulting in variable improvements in specific lung function markers, or it could be because inspiratory muscle training cannot reverse the pathological alterations of airway blockage.
The mMRC score is used to assess patients' level of dyspnea. In this research, the combined intervention improved patients' dyspnea, and the difference between the two groups was statistically significant (P = 0.042), which is consistent with the findings of previous reviews that inspiratory muscle training improves quality of life[55, 56]. Furthermore, the Renn BN research showed that cognitive behavioral treatment helped reduce dyspnea and the impact of illness on daily activities and functioning[43]. It's possible that there's a "steal phenomenon" in the inspiratory muscle[57], which means that the overall blood flow in the pulmonary circulation remains constant. When patients with inspiratory muscle weakness undergo strength training, the venous return velocity of this branch may be improved, improving ventilatory dysfunction and alleviating dyspnea symptoms[58]. Personal attention is crucial in managing dyspnea[30]. In this research, cognitive intervention of patients, requiring family members to accompany exercise, and required exercise in front of a mirror may play a role in diverting patients from excessive attention to dyspnea and cooperating with proper inspiratory muscle activity to reduce dyspnea.
The 6-minute walk test is a typical tool for evaluating patients' exercise capacity, and cognition combined with active cycle of breathing technology intervention can enhance patients' exercise ability. The control group's walking distance was (305.85 ± 31.95) meters, whereas the intervention group's walking distance was (323.48 ± 33.69) meters, and the difference was statistically significant (p = 0.007). This is consistent with the Gosselink R review, which found that IMT may enhance inspiratory muscle strength and endurance as well as functional exercise capacity[56]. Furthermore, Aliakbari F, who employed social cognitive theory as a theoretical framework for empowerment education, discovered that COPD patients who completed cognitive intense training had dramatically better daily activities[33]. It may be related to ACBT's ability to exercise patients' inspiratory muscle strength and endurance, strengthen the respiratory muscle pump and lung volume, increase venous return blood volume and left ventricular ejection volume, thereby accelerating the transport of oxygen in the body by skeletal muscle, improving overall perfusion of skeletal muscle, and finally increasing skeletal muscle oxygen uptake capacity and improving exercise capacity[59]. As protective behaviors, personal characteristics, interpersonal relationships, and environmental factors may all influence involvement in everyday activities. Some researchers feel that cognition, accurate comprehension, and right application of psychological components of behavior are the keys to enhancing motor ability[33]. In this research, cognitive intervention occurred concurrently with exercise training, showing that cognitive aspects may play a role and alter COPD patients' physical exercise capability.
The BODE index is used to evaluate the risk of mortality from respiratory disorders. Candemir undertook an 8-week pulmonary rehabilitation program for 228 COPD patients, and the BODE index reduced by 26%, from (4.7 ± 2.2) to (3.5 ± 1.8)[60]. López-García A observed that doing 20 sessions of muscle training on the included COPD patients might lower their BODE index[61]. It was also determined in our study that cognitive coupled with exercise intervention could considerably lower patients' BODE index (P = 0.009), which was compatible with the research of domestic scholar Tian Yujing[62]. This might be connected to improved lung function, alleviation of dyspnea symptoms, and increased exercise capacity.
Long-term worry and dread of illness have been demonstrated in studies to worsen patients' sense of dyspnea and negatively impact their quality of life[63]. After 8 weeks of the cognitive combined exercise intervention, we discovered that the intervention group improved their quality of life much more than the control group. The BODE index has a substantial inverse relationship with quality of life[64]. When the BODE index falls, patients' risk of mortality and hospitalization falls, which may be one of the causes for improved quality of life. According to research, patients' illness cognition has a direct impact on their quality of life, with pulmonary rehabilitation compliance and depression having a large chain mediation influence[65]. In this research, the cognitive intervention based on SCT assists patients in establishing right illness cognition, ensuring exercise compliance of patients via daily clock in and weekly follow-up, reducing anxiety and depression, and maybe improving their quality of life.
Limitations
This research has several limitations. To begin with, this was a non-randomized controlled trial, patients were recruited using a convenience sampling strategy, and the sample size was tiny owing to the project's short timeline. Second, owing to personnel, material resources, and COVID-19 constraints, this study only included patients from hospitals, and there was a paucity of research on other COPD patients, such as those in communities and nursing homes. Finally, blinding of investigators and participants was not feasible in this research, which may have skewed the findings.
Since this cognitive combined with active cycle of breathing technique developed in this study can have a significant effect on patients with moderate to severe COPD, it is suggested that researchers conduct higher quality and larger sample size randomized controlled trials to demonstrate the findings of this study. Given that this research only covered hospital-visiting patients, future studies could include a larger sample.