**1. Introduction**

Chronic obstructive pulmonary disease (COPD) is a common pulmonary disease characterized by persistent airflow limitation, which is usually associated with an enhanced chronic inflammatory response [1]. In addition, the harmful effects of toxic chemical particles or gases on the lungs often cause COPD; therefore, smoking is an important risk factor [1]. Epidemiological studies indicate that the prevalence of COPD is very common, ranging from 8% to 10% [2], and it causes significant economic and social burden worldwide [3].

The main therapeutic approaches for COPD include pharmacological treatment and lifestyle management such as cessation of smoking [4]. In pharmacological treatment for COPD, long-acting β2-agonist, long-acting muscarinic antagonists, inhaled corticosteroids,

**Citation:** Kwon, C.-Y.; Lee, B.; Lee, B.-J.; Kim, K.-I.; Jung, H.-J. Comparative Effectiveness of Western and Eastern Manual Therapies for Chronic Obstructive Pulmonary Disease: A Systematic Review and Network Meta-Analysis. *Healthcare* **2021**, *9*, 1127. https://doi.org/ 10.3390/healthcare9091127

Academic Editors: Manoj Sharma and Kavita Batra

Received: 13 July 2021 Accepted: 25 August 2021 Published: 30 August 2021

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and bronchodilators, among others, may be used alone or in combination, depending on the patient's condition or comorbidity [4].

COPD is a pathological condition associated with altered chest wall mechanics and musculoskeletal changes, and various manual therapies have been used as adjuvant therapy in combination with conventional medicine [5]. Although manual therapy is frequently used in clinical practice, some systematic reviews have pointed out that there is not enough evidence to support its therapeutic effect [6,7]. According to its theoretical basis, manual therapy can be classified as either based on Western medicine or on Eastern medicine. In the former case, it is applied based on the anatomical knowledge of the human body, such as manual therapy currently used in COPD, but in the latter case, manual therapy from a holistic perspective is applied within the body-mind-spirit model [8,9]. Previous studies that pointed out the lack of evidence for manual therapy for COPD have the limitation that they did not consider manual therapy based on Eastern medicine [6,7].

Various manual therapies take a common approach when the practitioner's body comes in contact with the patient's body; therefore, they will have a common expected effect along with the unique effect of each therapy, which leads to unique results for multiple outcomes of COPD. For example, advocators of Western manual therapy may explain that by improving musculoskeletal changes of altered chest wall mechanics, manual therapy can affect chest wall compliance of patients with COPD [5]. On the other hand, Eastern manual therapies are regarded as manual therapy combined with the traditional concept of meridian massage, and in this medical system, there is a view that both function and structure are systematically correlated [10]. Therefore, several Western and Eastern manual therapies can each have their own effectiveness for COPD, and comparative analysis of them can promote important individualized therapy in COPD management [11]. In addition, comparative analysis of Western and Eastern manual therapies for COPD could potentially help establish an integrative medical perspective for patients with COPD by combining the advantages of each.

Network meta-analysis (NMA) is a methodology that enables simultaneous comparison of various interventions at the same time [12]. By creating indirect evidence, it enables comparisons between interventions that are not directly compared by the existing clinical trials [12]. Therefore, this methodology can suggest the best intervention for each outcome to obtain optimal results for patients; further, it can be used to deduce clinical practice guidelines [13]. Until now, the effect of various manual therapies from the East and West on the outcome of COPD has not been comprehensively reviewed, and no attempts have been made to investigate the comparative effect of NMA. Therefore, this review aimed to compare the effectiveness and safety of several Western and Eastern manual therapies in COPD management. The results of this study will help to understand not only the clinical evidence of manual therapy for COPD more comprehensively but also understand the comparative effects of the presence or absence of a holistic approach (Western vs. Eastern).
