Benefits of herbal formulae containing Poria cocos (Fuling) for type 2 diabetes mellitus: A systematic review and meta-analysis

Background: Poria cocos (Schw.) Wolf or Fuling is one of the top 10 most frequently prescribed herbs in China for the treatment of type 2 diabetes mellitus (T2DM). Objective: The purpose of this systematic review is to determine the additional benefit of Fuling formulae use in addition to hypoglycaemic agents for T2DM in randomised clinical trials. Methods: English (5) and Chinese (4) medical databases were searched from their inception to August 2021. RCTs that included Fuling in herbal formulae for T2DM were included. Risk of bias were assessed using the Cochrane Collaboration’s procedures. Stata software (13.0) was used for data analysis. Results: Seventy-three RCTs (6,489 participants) with herbal formulae containing Fuling were included. Most studies were at risk of bias and strength of the evidence were low to moderate. Meta-analysis findings showed that the addition of formulae containing Fuling to hypoglycaemic agent-treatments could benefit people with T2DM by reducing fasting blood glucose (MD -0.82 [-0.93, -0.71]; I2 = 79.6%, P = 0.00), 2-hour postprandial blood glucose (MD-1.15 [-1.31, -0.98], I2 = 80%, P = 0.00) and haemoglobin A1c (MD-0.64 [-0.75, -0.53], I2 = 84.7%, P = 0.00). Adverse events were also significantly lower in the integrative group than in the hypoglycaemic alone group (RR 0.99 [0.93, 1.06], P = 0.87). Conclusion: Evidence from this study supports the use of Fuling formulae combined with hypoglycaemic agents for T2DM. The combined therapies appear to be well tolerated. Trail registration: This review is registered with the PROSPERO international prospective register of systematic reviews (CRD42020214635).