Resting Heart Rate as a Practical Alternative or Complement to Lipid Measures in Preferred Underwriting: Findings From the UK Biobank

Objectives.— We evaluated whether resting heart rate (RHR) could supplement or replace lipid-based measures in proxy preferred underwriting. Background.— RHR is a simple, noninvasive biometric associated with mortality. Preferred underwriting uses factors such as smoking status, body mass index, blood pressure, lipid measures, and medical history to identify lower-risk applicants. Unlike lipid-based measures, RHR may capture broader physiological health, including fitness, autonomic function, underlying illness, and lifestyle. Methods.— UK Biobank participants with RHR, underwriting risk factors, and mortality follow-up data were included. Preferred criteria required nonsmoking status, specified body mass index, blood pressure and lipid ranges, no use of medications with the potential to affect RHR, and no history of cancer, cardiovascular disease, or diabetes. Four preferred underwriting strategies were compared: lipid-based preferred , RHR substitution (volume-neutral) , RHR substitution (actual-to-expected [A/E]-neutral) , and lipid measures plus RHR . Mortality experience was assessed using A/E ratios based on Continuous Mortality Investigation insured lives tables. Results.— The cohort included 434,607 participants and 37,187 deaths, with an overall A/E ratio of 0.86 (95% confidence interval: 0.85, 0.87). The lipid-based preferred group had N = 49,931 and A/E = 0.75 (0.71, 0.79). The RHR substitution (volume-neutral) group identified 50,031 participants with a lower A/E ratio of 0.65 (0.62, 0.68). The RHR substitution (A/E-neutral) group identified 58,693 participants with an A/E ratio of 0.75 (0.72, 0.78). The Lipid measures plus RHR group lowered the A/E ratio to 0.66 (0.62, 0.71) but reduced N to 31,080. Conclusions.— RHR may be a practical alternative or complement to lipid measures in selected preferred underwriting contexts.