Herbal Products for Depression in Type 2 Diabetes Mellitus Patients: A Systematic Review and Meta-Analysis

Depression is prevalent in type 2 diabetes mellitus (T2DM) patients, and herbal products may be used as alternative therapies for this comorbidity. We conducted a meta-analysis to analyze the efficacy and safety of herbal product-related randomized controlled trials (RCTs) for patients with T2DM and depression. Scopus, Cochrane Library, Clinicaltrials.gov, Embase, PubMed, Ovid, Web of Science, China National Knowledge Infrastructure (CNKI), Chongqing VIP, SinoMed, and WanFang databases were retrieved from inception to September 2023 to collect RCTs that compared herbal products to placebo and selective serotonin reuptake inhibitors (SSRIs). The risk of bias assessments and a meta-analysis were conducted using Review Manager 5.4 and Stata 15.0. The study included 15 studies containing 16 trials. Our analyses revealed that herbal products were more effective than placebo in reducing the Hamilton Rating Scale for Depression-24 items (HRSD-24) (MD = -5.98, 95% CI [-7.92, -4.04], p < 0.00001, I² = 0%) and the Beck Depression Inventory-II (BDI-II) scores. Herbal products combined with SSRIs were better than SSRIs alone in decreasing the Hamilton Rating Scale for Depression-17 items (HRSD-17), HRSD-24, and self-rating depression scale (SDS) scores. The incidence of adverse events associated with herbal products was comparable to that observed with placebo and SSRIs. For patients with T2DM and depression, herbal products were more effective than placebo in relieving depression symptoms. Additionally, herbal products combined with SSRIs alleviated depression and blood glucose levels more effectively than SSRIs alone. To verify the clinical efficacy of herbal products, high-quality studies are warranted.