Literature Characteristics and Outcome Measures of Randomized Controlled Trials of Oral Traditional Chinese Medicine in Treatment of Acute Exacerbation of Chronic Obstructive Pulmonary Disease

Abstract

Background Oral traditional Chinese medicine (TCM) has been widely used in the treatment of acute exacerbation of chronic obstructive pulmonary disease (AECOPD), but the outcome measures of relevant clinical trials have not been standardized and regulated. Objective To screen the published randomized controlled trials (RCTs) of oral TCM in the treatment of AECOPD, summarize the literature characteristics and outcome measures, so as to provide reference for the design of clinical trials and the selection of outcome measures for the treatment of AECOPD with TCM. Methods CNKI, Wanfang Data, VIP, SinoMed, PubMed, Embase, Web of Science, Cochrane Library, ClinicalTrials.gov and Chinese Clinical Trial Registry were systematically searched by computer to obtain RCTs and clinical trial registration protocols for the treatment of AECOPD with oral TCM from January 2018 to October 2022. After independent screening of the literature and extraction of data by 2 researchers, qualitative analysis was used to describe the selection of outcome measures in the enrolled studies. Results A total of 578 studies were enrolled, including 574 RCTs with reported trial results and 4 clinical trial registration protocols. A total of 51 508 patients were involved in 574 RCTs. In the inclusion criteria, 88 studies limited the classification of disease, and 361 studies limited the TCM syndrome type, 6 studies reported the blinding method, and 6 studies mentioned the follow-up. A total of 4 030 outcome measures were covered and the number of outcome measures in a single article ranged from 1 to 24. According to the functional attributes, the outcome measures were classified into 8 measure domains: TCM symptoms/syndromes, symptoms/signs, physical and chemical tests, quality of life, long-term prognosis, economic evaluation, safety evaluation and others. The measure domain with the highest reporting rate was physical and chemical tests, and the top 5 outcome measure items reported in terms of frequency were: response rate (11.5%), forced expiratory volume in 1 s (FEV1) (7.5%), TCM symptom/syndrome score (7.0%), FEV1/Forced Vital Capacity (FVC) (6.8%), FVC (4.6%). Four hundred and forty-five studies reported the composition of response rate, and the top 5 measures with reporting rate were symptoms (423), signs (281), TCM syndrome score (203), laboratory tests (89), and pulmonary function (71) . Conclusion The RCTs of oral TCM in the treatment of AECOPD involved a large number and a wide range of outcome measures. The included literature focused on the effects of oral TCM on the symptoms and signs, physical and chemical test indicators, quality of life, long-term prognosis, economic evaluation and safety outcomes of patients with AECOPD in varying degrees. However, the selection of outcome measures remains problematic in multiple ways: unclear prioritization of outcome measures; focusing on clinical endpoints with insufficient attention to clinical endpoints; insufficient attention to health economics indicators; different sources and judgment criterias of reference of response. In the future studies, researchers can design the rational outcome measures by refering to the published core outcome set (COS) to improve the quality of TCM clinical research.

Keywords

• traditional chinese drugs|pulmonary disease, chronic obstructive|acute exacerbation period|randomized controlled trial|patient reported outcome measures