Traditional Chinese Medicine Body Constitutions as Predictors for Depression: A Systematic Review and Meta-Analysis

Traditional Chinese medicine body constitution (TCMBC) reflects a person's vulnerability to diseases. Thus, identifying body constitutions prone to depression can help prevent and treat depression. The review aimed to assess and summarize the existing evidence that explores the relationship between TCMBC and depression. Psychology and Behavioral Sciences Collection, MEDLINE, PubMed, CNKI, Wanfang, SinoMed, Embase, VIP, CINAHL, and CMJ were searched from inception to April 2021. Observational studies assessing the association between TCMBC and depression were selected. The quality of the included studies were assessed using the Newcastle-Ottawa Scale (NOS). Eighteen studies were included in the systematic review and thirteen in the meta-analysis. The pooled odd ratios of developing depression for Qi-stagnation, Qi-deficiency, Yang-deficiency, Yin-deficiency, and Balanced constitutions were 3.12 (95% CI, 1.80-5.40; I-2 = 94%), 2.15 (95% CI, 1.54-3.01; I-2 = 89%), 1.89 (95% CI, 0.71-5.03; I-2 = 81%), 1.41 (95% CI, 0.91-2.20; I-2 = 57%), and 0.60 (95% CI, 0.40-0.90; I-2 = 94%), respectively. The findings suggest that the evaluation of a person's TCMBC could be useful the in prevention and treatment of depression. However, more case-control and cohort studies are required to further confirm the association between TCMBC and depression.