Traditional Chinese medicine Shenqi compound to improve lower extremity atherosclerosis of patients with type 2 diabetes by affecting blood glucose fluctuation: Study protocol for a randomized controlled multicenter trial.

Background: Clinical and basic research supports that blood glucose fluctuation is an important predictor of diabetic vascular disease and an etiology of lower extremity atherosclerosis, which is an important pathological basis for lower extremity vascular diseases. Previous Chinese National Natural Science Foundation trials (No. 81503566) have reported that the traditional Chinese medicine Shenqi compound can reduce blood glucose fluctuation and low-grade inflammation, and protect blood vessels; however, there are no high-quality clinical evidences available to support the same. This multicenter randomized controlled trial aims to obtain more clinical evidence to confirm the efficacy and safety of Shenqi compound in type 2 diabetes with lower extremity atherosclerosis.

Methods: A multicenter RCT will be implemented in this study for a 32-week study period (8 weeks for intervention and 24 weeks for follow-up). Participants will be recruited from the Teaching Hospital of Chengdu University of TCM, Mianyang Hospital of TCM, and Shuangliu Hospital of TCM. Sixty participants will be randomly divided into a treatment group (basic treatment combined with traditional Chinese medicine Shenqi Compound) or a control group (basic treatment combined with Chinese medicine placebo) with 30 participants in each group. Patients will be selected considering the following inclusion criteria: age between 35 and 65 years, and a positive diagnosis for type 2 diabetes with lower extremity atherosclerosis and TCM syndromes. Primary outcome indicator is an arterial color Doppler ultrasound. Secondary outcome indicators include: blood glucose fluctuation indicators (MBG, SDBG, LAGE), islet β-cell function evaluation indicators (Homa-IR, Homa-islet, SG, SCP), inflammation indicators (NLR, CRP, IL-6), blood lipids, and HbA1c. Safety index includes vital signs (T, P, R, BP), blood, urine, stool routine, liver and renal function, electrocardiogram, and adverse event records. The endpoint event is defined as the presence of gangrene in the lower limbs.

Discussion: Explore the clinical effect of traditional Chinese medicine "Shenqi Compound" to reduce blood glucose fluctuation and use HOMA-IR, the area under the glucose curve, and the area under the C-peptide curve to evaluate the effect of protecting islet β cell function.

Trial Registration: Chinese clinical trial registry (ChiCTR-1900027693). Registered on November 23, 2019. http://www.chictr.org.cn.