Efficacy and Safety of Acupuncture and Related Techniques for Type 2 Diabetes Mellitus: A Systematic Review of 21 Randomised Controlled Trials

Background: This systematic review aimed to evaluate the effects of acupuncture on hypoglycaemic outcomes. Methods: PubMed, Embase, Cochrane library, and ClinicalTrials.gov were searched up to July 5, 2020, to identify randomised controlled trials (RCTs) that enrolled patients with T2DM and compared acupuncture and related techniques combined with antidiabetic drugs to antidiabetic drugs alone. The primary outcomes were haemoglobin A1c (HbA1c) and fasting blood glucose (FBG). The secondary outcomes included two-hour blood glucose (2hBG), fasting insulin (FINS), homeostatic model assessment for insulin resistance (HOMA-IR), and acupuncture- related adverse events. Results: Twenty-one RCTs (n=1188) were included. The meta- analytic results showed that compared with the control group, the acupuncture group had greater reductions in FBG (mean difference -6.46 mg/dl, 95% CI -11.95 to -0.98; high-quality evidence) and HOMA-IR (MD -1.23, 95% CI -2.16 to -0.31; low-quality evidence) but comparable changes in HbA1c (MD -0.39%, 95% CI -0.84 to 1.61; very- low-quality evidence), 2hBG (MD -4.99 mg/dl, 95% CI -20.74 to 10.76; low-quality evidence), and FINS (MD -1.32 μIU/ml, 95% CI -3.76 to 1.12; low-quality evidence). No data on the incidence of diabetic complications were found. All acupuncture-related adverse events reported were mild. Conclusions: The current evidence suggest that acupuncture, as a complementary therapy to antidiabetic drugs, has a small but statistically significant ability to decrease FBG. Limited evidence shows that acupuncture may also improve insulin resistance. The effects of acupuncture on HbA1c, 2hBG, and FINS remain uncertain. Acupuncture is generally safe in patients with mild diabetes.