Life expectancy gap between the least and most educated widened to nearly 11 years by 2019, highlighting the urgent need to address education as a key social determinant of health.
Study: Life expectancy by county and educational attainment in the USA, 2000–19: an observational analysis. Image Credit: Miha Creative/Shutterstock.com
A recent study published in The Lancet Public Health investigated disparities in life expectancy by educational attainment in the United States (US) counties.
Education is a major social determinant of health and a human right. A large body of evidence suggests a relationship between socioeconomic factors and longevity or mortality.
In the US, higher educational levels have been associated with an increased life expectancy; notably, the disparities in life expectancy between individuals with lower and higher educational levels have widened in recent decades. These gaps represent a significant health disparity, but data at local levels are sparse.
About the study
In the present study, researchers estimated life expectancy at 25 years for 3,110 US counties over two decades (2000-19). Previous methods for life expectancy and mortality estimation were adapted to estimate life expectancy by US county for four educational attainment groups: 1) less than high school, 2) high-school graduates, 3) college graduates, and 4) some college (incomplete or associate degrees).
Death records were obtained from the National Vital Statistics System by age group, sex, county of residence, year, and educational attainment. Four states lacked data on education in death records for some period and were thus excluded from analyses.
Population estimates, stratified by age group, year, sex, and county, were generated using data from the National Center for Health Statistics, the American Community Survey, and the 2000 decennial census.
Small-area estimation models were used to compute mortality rates by county, year, age, sex, and educational attainment.
Estimated mortality rates were adjusted using educational attainment misclassification ratios, viz., the ratio of deaths among individuals in an educational attainment population based on self-reports to those in the same population based on death certificate records.
Findings
There was a consistent gradient in life expectancy by educational attainment in the US throughout the study period. Individuals with a higher level of education had a higher life expectancy in all years.
College graduates had a higher life expectancy than those with some college education. People who with some college education had higher life expectancy than high-school graduates. Likewise, high school graduates had a higher life expectancy than the least educated population.
Females had a higher life expectancy than males in all education groups and years. Life expectancy increased by 2.1 years for all populations combined between 2001 and 2019. This increase varied by educational attainment, with the highest increase (2.5 years) for college graduates.
No changes in life expectancy were noted for the least educated population. Further, the overall increase in life expectancy was slightly larger for males.
Most of the life expectancy gains occurred pre-2010 for each group. Only college graduates experienced life expectancy gains during 2000-10 and 2010-19, while the other populations gained life expectancy before 2010 and experienced decreases post-2010.
Life expectancy varied highly at the county level in 2019 between and within populations. For all populations combined, the estimated life expectancy ranged between 68.2 and 93.2 years.
Central Colorado counties had relatively high life expectancy for all populations, while counties in the southeast had low life expectancy.
Life expectancy was higher for college graduates in 81% of counties than among individuals completing some college education; it was higher in people with some college education than among high-school graduates in 97.7% of counties.
Further, high school graduates had a higher life expectancy in about 96% of counties than those with less than a high school education. Around 85% of counties had increased life expectancy throughout the study period for all populations combined.
Notably, the life expectancy advantage of more educated populations relative to less educated populations within the same county widened more often than it narrowed.
Conclusions
The study estimated life expectancy by educational attainment and county during 2000-19 in the US. Substantial disparities emerged by educational attainment, which in many cases grew over time and were geographically widespread. The difference between the least and most educated groups was large, nearly 11 years in 2019.
Life expectancy gains were concentrated among the most highly educated, while those with less than a high school diploma had no gains.
Further research is required to ascertain how more equitable access to education and efforts to reduce barriers might augment health and lead to longer lives.
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