All-Cause Mortality and Life Expectancy by Birth Cohort Across US States.

Importance: Although overall US mortality rates declined from 1969 to 2020, they vary considerably by state and generation, especially when evaluated by birth cohort. Trends in mortality and life expectancy by birth cohort for US states and Washington, DC, have yet to be characterized. Objective: To estimate cohort mortality trends for each state and Washington, DC, and quantify life expectancy at birth and 40 years of age and the rate of increase after 35 years of age. Design, Setting, and Participants: In this cohort study, all-cause mortality rates by single years of age (0-119) and birth cohort (1900-2000) were estimated for each state in January 2025. Mortality data and population estimates were obtained from the National Center for Health Statistics, the Centers for Disease Control and Prevention Wide-Ranging Online Data for Epidemiologic Research website, and the Surveillance, Epidemiology, and End Results database for each state and Washington, DC, by single years of ages 0 to 84 and calendar years 1969 to 2020. An age-period-cohort model with constrained cubic splines for temporal effect estimates was used to estimate mortality from 1900 to 2000. Main Outcomes and Measures: Life expectancy for each cohort from birth or 40 years of age was estimated by sex and state, along with doubling time for the death rate after 35 years of age. Results: Analyses included 179 million deaths (77 million female and 102 million male). In the West and Northeast, cohort life expectancy improved from 1900 to 2000, but in some Southern states, it changed less than 3 years since 1900 in females and less than 2 years since 1950 in males. Washington, DC, had the lowest life expectancy in the 1900 birth cohort but a greater increase than the other states (from 61.1 to 72.8 years of age). After 35 years of age, the highest rate-doubling time in a state was 9.39 years in New York for females and 11.47 years for males in Florida. The shortest rate-doubling times were 7.96 years for females in Oklahoma and 8.95 years for males in Iowa. Conclusions and Relevance: Cohort-specific patterns across states reveal wide disparities in mortality. Some states have experienced little or no improvements in life expectancy from the 1900 to 2000 birth cohorts. Understanding how mortality patterns vary by birth cohort within each state can inform decision-making around resource allocation and public health interventions.