Long‐term trends in metabolic profiles across Chinese birth cohorts: A real‐world big data analysis

BACKGROUND: The global burden of metabolic diseases is increasingly severe, with a continuous rise in prevalence among younger populations. There is an urgent need to explore the long-term trends of metabolic risk factors across generations. This study aimed to investigate birth cohort effects on metabolic profiles among Chinese adults to provide a basis for precision prevention and control. METHODS: This retrospective longitudinal study analysed real-world clinical laboratory data (2010-2024) from Fudan University Zhongshan Hospital in China including five metabolic indicators-fasting glucose (FG), total cholesterol (TC), triglycerides (TG), low-density lipoprotein cholesterol (LDL-C) and high-density lipoprotein cholesterol (HDL-C). The study included 3 888 861 adults born between 1930 and 1999, with 9059 individuals forming a fixed cohort for annual testing. Birth cohorts were defined in 10-year intervals from the 1930s to the 1990s. Linear regression (overall population) and mixed-effects models (fixed cohort) were used to assess cohort trends, adjusting for age and sex. RESULTS: In the overall population, compared with earlier birth cohorts, later cohorts had significantly higher levels of FG (1990s vs. 1930s: +.438 mmol/L; p < .001). Lipid changes were more complex: TC and LDL-C decreased in earlier cohorts (1930s‒1970s) but rebounded in the 1980s‒1990s (LDL-C [1990s vs. 1930s]: +.034 mmol/L; p < .001), while HDL-C and TG continued to decline (HDL-C [1990s vs. 1930s]: ‒.075 mmol/L; TG [1990s vs. 1930s]: ‒.218 mmol/L; p < .001). Additionally, a fixed cohort with repeated annual measurements was established to provide longitudinal validation, enhancing the robustness of findings against population variability. CONCLUSIONS: The significant birth cohort effects on metabolic indicators suggest that younger generations, particularly those 1980s‒1990s cohorts, face greater metabolic risks than 1930s‒1970s cohorts. These findings support intensifying early screening of blood glucose and lipid profiles and encourage prompt dietary and lifestyle modifications to counter the rising metabolic trends in the 1980s-1990s cohorts. KEY POINTS: Younger generations (1980s-1990s) exhibit higher fasting glucose and rebounding total cholesterol and low-density lipoprotein cholesterol, alongside declining high-density lipoprotein cholesterol and triglycerides compared to 1930s-1970s cohorts. A large fixed cohort with longitudinal follow-up robustly confirms the accelerated metabolic risk accumulation in younger Chinese generations. Findings underscore the critical need for early screening and preventive strategies targeting the 1980s-1990s birth cohorts.