OBJECTIVE To observe the clinical efficacy of Yangyin Yifei Decoction in treating type 2 diabetes mellitus (T2DM) patients with of qi-yin deficiency and elevated serum keratin 19 fragment (Cyfra21-1).

METHODS Sixty patients with T2DM of qi-yin deficiency type and elevated serum Cyfra21-1 who met the inclusion criteria were selected and randomly divided into an observation group and a control group, 30 cases in each group. The control group was given oral hypoglycemic treatment with metformin hydrochloride sustained-release tablets and dapagliflozin tablets, and the observation group was given Yangyin Yifei Decoction on the basis of the treatment of the control group. The treatment course of both groups was 12 weeks. Before and after treatment, the changes of traditional Chinese medicine (TCM) syndrome scores, fasting blood glucose (FBG) and 2-hour postprandial glucose (2 h PG), glycosylated hemoglobin (HbAlc), serum Cyfra21-1 and Cyfra21-1 specific T cell response, triglycerides (TG), total cholesterol (TC), alanine aminotransferase (ALT), aspartate aminotransferase (AST), urea (UR), and creatinine (CREA) were observed in the two groups.

RESULTS After treatment, FBG, 2 h PG, HbAlc, and TCM syndrome scores of the two groups of patients decreased significantly (P < 0.05, P < 0.01), and the observation group was better than the control group (P < 0.05, P < 0.01); TG and TC in the observation group were significantly reduced (P < 0.01), serum Cyfra21-1 was significantly decreased (P < 0.01), and Cyfra21-1-specific T cells in PBMCs were significantly increased (P < 0.01), which was better than the control group (P < 0.01); there was no significant change in liver and kidney function in the two groups.

CONCLUSION Yangyin Yifei Decoction combined with basic hypoglycemic regimen can significantly improve blood glucose and lipid metabolism in type T2DM patients with qi-yin deficiency and elevated serum Cyfra21-1, enhance the function of Cyfra21-1-specific T cells, and improve the body's immunity, with high safety.