Underwriting mortality risk using cognitive function tests

Evaluate the association of selected cognitive function assessments, including two memory tests and two mental status tests, with all-cause mortality.

Associations between the selected cognitive function tests and mortality were assessed in a longitudinal dataset. The Health and Retirement Study (HRS) includes 27,648 individuals, most of whom were 65 years of age and older; study participants were followed for an average of 8.9 years, and over this interval, 8268 deaths occurred. The association of 4 cognitive function test scores at entry into the study and the observed rates of mortality were evaluated using both a traditional (actuarial) actual vs expected mortality method and a Cox proportional hazard model adjusted for age, gender, smoking, and other covariates.

Each cognitive function test was shown to be independently associated with mortality after adjustment for covariates. Further, individual test scores, fit using a continuous model, were shown to be correlated with mortality outcomes. The associations appear to be stronger at a younger age when only age, gender, and smoking were adjusted, but such effect modifications were no longer statistically significant after additional covariates were adjusted. The associations did not appear to be attenuated in a pre-defined "healthy" subgroup, suggesting that the result could be extrapolated to applicants who would qualify for life insurance.

Cognitive function, as measured by 4 simple screening tests, was shown to be significantly and independently associated with all-cause mortality in a longitudinal dataset of individuals, the majority of whom were 65 years of age and older.