AUTHOR=Tang Haoqing , Li Mingyue , Ji Xiaokang , Zhao Qingbo , Wang Yongchao , Zhao Yifu , Wang Qing , Xue Fuzhong , Liu Xiaoyun 

TITLE=Complication development trajectories for patients with type 2 diabetes mellitus: evidence from a five-million retrospective cohort study

JOURNAL=Frontiers in Health Services

VOLUME=Volume 5 - 2025

YEAR=2025

URL=https://www.frontiersin.org/journals/health-services/articles/10.3389/frhs.2025.1699513

DOI=10.3389/frhs.2025.1699513

ISSN=2813-0146

ABSTRACT=BackgroundType 2 diabetes mellitus (T2DM) is a growing health burden in China. High complication rates contribute to increased morbidity, mortality, and costs. However, evidence is limited regarding how these complications develop and cluster over time in real-world settings, which this study examined.MethodsThis retrospective cohort study used big data from the Cheeloo Lifespan Electronic Health Research Data Library, comprising data from over 5 million individuals in Shandong Province, China, to investigate the trajectories, onset timing and key risk factors of T2DM-related complications.ResultsThe prevalence of T2DM-related complications increased from 30.4% in 2013 to 53.1% in 2023. The median time from diagnosis to the first complication was 7.5 years. Ophthalmic, neurological, and circulatory complications were among the most common and showed the largest relative increases in prevalence over the study period. Complication profiles exacerbated over time: most patients developed multiple complications by Year 9. Frequent follow-up visits (≥4 times/year) and using primary health care (PHC) services were significantly associated with a reduced risk of complications, whereas being unmarried, being overweight, being obese, alcohol use, and poor medication adherence were significantly associated with a higher risk.ConclusionPatients with T2DM in China face a substantial and growing burden of complications, with most developing multiple complications within ten years of diagnosis. Follow-up visits, the use of PHC services, and regular medication adherence are potential protective factors to prevent or delay the development of complication. These findings highlight the importance of integrated, community-based, and personalized management strategies to improve outcomes in T2DM populations.