Abstract: Objective To investigate the association between diabetes subtypes, classified using a novel typing method, and the risk of cardiovascular disease, in order to promote precision subtype management and optimize primary prevention strategies for cardiovascular diseases. Methods A retrospective cohort study was conducted on 843 patients newly diagnosed with type 2 diabetes mellitus (T2DM) between 2015 and 2022. Baseline clinical data were collected, and patients were categorized into four subtypes using K-means clustering. They were followed up until July 2025 to determine cardiovascular outcomes, and the risk of cardiovascular events among the subtypes was compared. Results Among the 828 T2DM patients, 146 (17.63%) were classified as Severe Insulin-Deficient Diabetes (SIDD), 168 (20.29%) as Severe Insulin-Resistant Diabetes (SIRD), 173 (20.89%) as Mild Obesity-Related Diabetes (MOD), and 341 (41.18%) as Mild Age-Related Diabetes (MARD). Significant differences in age, BMI, and other indicators were observed among the different subtypes (P<0.05). A total of 86 patients (10.39%) developed cardiovascular diseases. The incidence was 15 cases (10.27%) in the SIDD subtype, 30 (17.86%) in the SIRD subtype, 18 (10.40%) in the MOD subtype, and 23 (6.74%) in the MARD subtype. There was a statistically significant difference in the incidence of cardiovascular diseases among the subtypes (Log-rank χ²=17.132, P=0.001). Multivariate Cox analysis revealed that T2DM subtypes (SIDD: HR=3.484, SIRD: HR=4.999, MOD: HR=6.287), age, eGFR, and LDL-C were influencing factors. Both the Fine-Gray competing risk model and the cause-specific Cox model indicated that the SIRD subtype was an independent risk factor (HR=2.710 and 2.855, respectively; P<0.001), while the effects of the SIDD and MOD subtypes were not statistically significant (P>0.05). Conclusion The novel classification method can effectively assess the risk of cardiovascular disease in patients with T2DM. The SIRD subtype represents a high-risk population that should be prioritized for intervention.

Key words: Type 2 diabetes mellitus, Diabetes subtypes, Cardiovascular disease, Major adverse cardiovascular events, Retrospective cohort study, Cluster analysis