Distribution of traditional Chinese medicine syndromes in 1,989 patients with metabolic syndrome and correlation analysis of comorbidities

To investigate the distribution characteristics of traditional Chinese Medicine (TCM) syndromes among patients with metabolic syndrome (MetS), thereby providing evidence to support the standardization of TCM syndrome differentiation and optimization of clinical management strategies.

A retrospective cross-sectional study was conducted, and 1,989 patients with MetS hospitalized in the comprehensive ward of Guang′anmen Hospital, China Academy of Chinese Medical Sciences, from September 2018 to September 2021 were included. Collected data included general information (sex, age, blood pressure, triglycerides, high-density lipoprotein, and fasting blood glucose), TCM four diagnostic information (symptoms/signs, pulse manifestation, and tongue manifestation), and common comorbidities(hypertension, coronary heart disease, stroke, chronic kidney disease, fatty liver disease, and heart failure). General characteristics and clinical indicators were analyzed using descriptive statistics. Descriptive and factor analyses were performed on the four diagnostic data to obtain the loading coefficients of the diagnostic information, as well as the syndrome elements of disease nature and location. Cluster analysis was used to summarize the distribution characteristics of TCM syndrome types, and binary logistic regression was applied to analyze the correlation between common comorbidities and syndrome types.

Among the 1,989 patients with MetS, males accounted for 48.47% (964/1,989), females for 51.53% (1,025/1,989), and patients aged ≥60 years accounted for 73.60% (1,464/1,989). A total of 134 items of TCM four diagnostic information were extracted. The most frequent symptoms/signs were wiry pulse (58.77%; 1,169/1,989), white tongue coating(50.63%; 1,007/1,989), purplish-dark tongue(49.77%; 990/1,989), and greasy tongue coating (49.02%; 975/1,989). Factor analysis was conducted on 38 four diagnostic information with a frequency greater than 10%. Sixteen common factors were extracted, with a cumulative variance contribution rate of 58.97%. The syndrome elements of disease location primarily involved the kidney, liver, and spleen, extending to the heart and lungs; the syndrome elements of disease nature were predominantly qi deficiency, dampness, and yang deficiency. Cluster analysis identified four main syndrome types: liver depression and spleen deficiency with phlegm-qi stagnation (43.41%; 863/1, 988); heart-lung qi deficiency with kidney yang insufficiency(31.79%; 632/1,988); lung-kidney yang deficiency with internal retention of phlegm-fluid (19.92%; 396/1,988); and qi-yin deficiency with damp-turbidity obstruction the middle jiao (4.88%; 97/1,988). Correlation analysis of comorbid diseases showed that hypertension was the most common comorbid disease, followed by coronary heart disease and heart failure. Among the different syndrome types, hypertension accounted for the highest proportion in heart-lung qi deficiency with kidney yang insufficiency, liver depression and spleen deficiency with phlegm-qi stagnation, and qi-yin deficiency with damp-turbidity obstruction the middle jiao, with proportions of 49.84% (315/632), 41.37% (357/863), and 49.48% (48/97), respectively. In contrast, lung-kidney yang deficiency with internal retention of phlegm-fluid had the highest proportion of heart failure, at 60.86% (241/396).

The TCM pathogenesis of MetS is characterized by root deficiency and branch excess. The disease is primarily located in kidney, the liver, and spleen, involving the heart and lungs. Its syndrome distribution centers around liver stagnation and spleen deficiency with intermingled phlegm and qi, often accompanied by qi deficiency, yang deficiency, and internal damp-turbidity retention. Furthermore, different syndromes may have specific directional associations with certain comorbidities.