Evidence-based Chinese medicine approach for atopic eczema: current state of evidence and future priority
Creators: name: Gu, Xuming
Publisher: name: RMIT University
Year: 2024
Subjects: classificationCode: 420803
subject: Traditional Chinese medicine and treatments

description: Atopic eczema (AE) or atopic dermatitis is an inflammatory skin disease characterised by chronic relapse and remission associated with severe pruritus and skin lesions. The prevalence of AE has increased globally over the last three decades. In Australia, a 12-month period prevalence of AE was 17.2% in school students aged from six to seven years and 24.8% in children aged eight to 11 years. The pathogenesis of AE is yet to be fully elucidated; the risk factors associated with the increasing prevalence of AE are better understood. Clinically topical administration of corticosteroids or calcineurin inhibitors is the standard first-line pharmacotherapy for mild AE. Systemic medications including oral corticosteroids or immunosuppressive drugs are used for more difficult-to-treat or refractory moderate or severe AE patients. However, application of systemic medications over a long time can lead to unwanted adverse events. Therefore many AE sufferers have chosen to use alternative therapies including Chinese herbal medicine (CHM) to manage their AE. In spite of long-term use of CHM in clinical practice and the recently increasing clinical literature concerning the benefit of CHM treatment for AE, the current state of evidence for topical and oral CHMs has not been systematically evaluated. It should be noted that despite such evidence gaps, a series of CHM formulae for AE has been included and recommended in the Chinese Medicine Guidelines 2011 and Expert Consensus 2013 (publication 2). The present thesis aimed to address this by evaluating the current literature and identifying priority targets for generating new clinical evidence. Specifically, this research aimed: 1) to systematically evaluate the current state of clinical evidence with respect to benefits and safety of CHM for patients with AE; 2) to identify new clinical research priority(ies) and develop a protocol for a randomised, double-blind, placebo-controlled clinical trial; and 3) to conduct a pilot study to determine the feasibility of the trial protocol and to gather preliminary data for the efficacy and safety of Pei-Tu-Qing-Xin granules (PTQX), a CHM preparation for children aged six to 16 years with moderate to severe AE. To address research question 1), two systematic reviews with meta-analysis were conducted and published (publications 4 and 5). The first systematic review included 10 randomised controlled trials (RCTs) involving 1,058 participants who were treated topically with CHM or positive pharmacotherapy control interventions. Meta-analysis of these 10 trials shown an overall effect in favour of CHM in terms of 'total effectiveness rate' when compared to topical conventional medications. However, caution should be given to these finding due to the high 'risk of bias' and significant methodological flaws of the included trials. The second systematic review was a Cochrane Systematic Review which included 28 RCTs involving 2,306 children and adults. In most of the included studies, a higher number of participants were reported to reach clinical remission and significantly lower scores of itching in CHM groups when compared with the control groups. Again, most of the included studies were assessed as high 'risk of bias'. Hence findings need to be interpreted with caution. The above two systematic reviews concluded that while promising overall benefits were shown, well-designed, adequately powered RCTs were needed to determine the clinical efficacy and safety profile of the key CHM interventions for AE. To address research questions 2) and 3) based on the key findings from the two systematic reviews, a trial protocol for an RCT was developed and approved by the RMIT Human Research Ethics Committee (HREC) in 2014 and published in 2015 (publication 3). Using this published protocol, a pilot study was carried out between August 2016 and September 2017 in an out-patient clinical setting. The pilot study was a parallel design, randomised, double-blind, placebo-controlled, prospective clinical trial. It aimed to determine the feasibility of the protocol and to gather preliminary data concerning efficacy and safety of a common Chinese herbal formula (PTQX) for children aged six to 16 years who were diagnosed with moderate or severe AE. The trial medications were given to participants for oral ingestion with a dosage of four grams of trial medications twice daily (total of eight grams) for six to seven year olds and six grams twice daily (total of 12 grams) for eight to 16 year olds, for 12 weeks and cessation of medications for four weeks during the follow-up period. The trial protocol was successfully implemented. All mean scores of eczema area and severity index (EASI), patient-oriented eczema measure (POEM) and children's dermatology life quality index (CDLQI) in the PTQX group were lower than those in the placebo group at the end of follow-up. Furthermore, a more obvious trend of decrease in total dosage of topical corticosteroid creams which were routine medication (concomitant medication) used by participants in both groups was recorded in the PTQX group although no statistically significant between-groups differences were detected. This may be due to the small sample size (n=30, 16 in PTQX group) involved in the pilot study. The feasibility of the trial design and the overall positive trend demonstrated in the outcome measures support the conduct of a full-scale trial to address the clinical evidence gap (publication 1). In conclusion, the present research employed rigorous methodologies and applied evidence-based approaches to determine the current state of clinical evidence for the efficacy and safety of CHM in AE. While recognising the methodological weakness of the included studies in the two systematic reviews, the promising positive findings have enabled us to identify research priorities and to develop a trial protocol for an appropriately powered RCT to generate new clinical evidence that will support sound clinical decision making. Further, a completed pilot study, which was designed to overcome the weaknesses and risk of bias inherent in the published literature, demonstrated the feasibility of the trial protocol and showed a positive trend for the benefit and safety of the CHM preparation. Given the clinical challenges to offer effective and safe therapeutics for the patient population, an adequately powered trial on this herbal preparation is warranted as a priority to deliver evidence appropriate for the development of Chinese medicine therapy for AE.