Predicting the Timing of Metabolic Category Transitions in Chilean Mining and Allied Industrial Workers: A Survival Analysis of Preemployment Examinations

Objective: To quantify the time-dependent risk of metabolic worsening in Chilean mining and allied industrial workers. Methods: Retrospective cohort of 418,699 preemployment examinations (2021–2024). Worsening was a higher BMI or fasting-glucose category at the next examination. Kaplan–Meier and Cox models estimated hazard ratios (HR). Results: Analyses comprised 28,300 BMI and 27,269 glucose examination pairs. Glucose worsening rose with age (>55 years HR 1.82), male sex (HR 2.90) and higher baseline BMI (HR 1.49–1.65), all p<0.001. Among workers who worsened, median time to transition was 7 months (BMI) and 9 months (glucose); 19% worsened within 12 months. Conclusions: Survival analysis turns a static fitness decision into dynamic surveillance. Older age, male sex and higher baseline BMI predict faster glucose worsening; most transitions occur within the annual re-examination interval.