Hazard Ratio to Life Expectancy: Gompertz-Makeham Validation of Emerging Risk Factors Collaboration Cardiometabolic Multimorbidity Tables

Objective.—: To validate Emerging Risk Factors Collaboration (ERFC) high-risk cardiometabolic life years lost (LYL) tables using Gompertz-Makeham calibrated to hazard ratios, offering a reproducible framework for insurance underwriting and medico-legal life expectancy projections. Methods.—: ERFC LYL tables (91 cohorts; 689,300 participants; HR≥5) benchmarked against Irish Life Tables No. 17 via constant HR∼9.5 multiplier. Gompertz-Makeham generated risk-group survival curves; LYL as baseline-risk differential ages 40-85. Model performance via mean absolute error (MAE). Results.—: Gompertz-Makeham reproduced ERFC high-risk LYL (males MAE 1.21 years; females 1.16 years across 40-85), preserving empirical S-curve without disease-specific adjustments (Table 2; Figures 1-3). Age 40 loses, 20-22 years; age 75, 5-6 years. Conclusions.—: HR-calibrated Gompertz-Makeham provides aetiology-independent LYL estimates within 1 - 2 years mean absolute error (MAE), extending Strauss/Shavelle disability models to multimorbidity for actuarial risk assessment and forensic reports.