In a recent systematic review and meta-analysis published in The Lancet Public Health, researchers assessed the effect of education on all-cause mortality risk in adults on a global scale.
Study: Effects of education on adult mortality: a global systematic review and meta-analysis. Image Credit: Drazen Zigic/Shutterstock.com
Background
There is a link between increased schooling and better health; however, studies have not estimated the magnitude of this relationship globally.
It is one of the most crucial health determinants, besides technological progress, access to quality healthcare, clean water and sanitation, and labor rights. Besides health, education drives socioeconomic empowerment across all genders.
Thus, the UN Sustainable Development Goals (SDGs) 4.1 & 4.3, adopted in 2015, specifically ensure primary and secondary education for children and tertiary education for adults.
Education of adults, especially maternal education, has been shown to reduce mortality in children aged ≤5 by 3% and parental education by 1.6%.
About the study
Researchers thoroughly searched seven databases, including Web of Science, PubMed, and Scopus, to name a few, and identified all research publications assessing all-cause mortality as an outcome and years of schooling as an independent variable. They retrieved all papers from January 1, 1980 to June 16, 2023.
Two teams of reviewers then assessed these studies for individual-level data on education and mortality.
One person extracted data into a standard template derived from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD).
Next, they implemented mixed-effects meta-regression models to address between-study heterogeneity, adjusting for study-level covariates, including age, sex, and marital status, and reporting uncertainty in its estimation. They also generated funnel plots to assess publication or reporting bias.
Results
This systematic review was the most comprehensive qualitative synthesis of articles with individual-level data, not restricted to any country or period; additionally, it exceeded the scale of previous research on educational attainment and mortality.
The authors identified 17,094 unique papers, of which 603 met the eligibility criteria for inclusion in the analysis. These papers covered 10,355 observations from 59 countries.
The observed relationship of all-cause adult mortality with education was dose-dependent, with an average reduction in mortality risk of 1·9% per additional year of schooling.
On average, an adult with 12 years of schooling was at 24·5% lowered risk of mortality than an adult who never went to school.
This effect was greater in younger people than in older adults. Accordingly, the average reduction in mortality risk related to an additional year of education for adults aged 18–49 years and 70+ was 2.9% and 0.8%, respectively.
However, educational inequalities in mortality were persistent across the entire lifespan, and this pattern remained the same across birth cohorts and periods.
The protective effect of educational attainment on all-cause adult mortality by gender or Socio-demographic Index level did not vary; however, this observation requires further investigation.
On the other hand, the effects of education on mortality risk are comparable to other high-impact social determinants, underscoring the benefits of increased investment in education on future population health.
For example, the risk of all-cause mortality for an adult with no education compared with 18 years of education is similar to a person who currently smokes (5 pack-years) compared to a nonsmoker (RR ~1·52), underscoring the crucial importance of increased and equitable educational attainment as a global health goal.
Conclusions
This study adds to the limited body of scientific work on inequitable adult all-cause mortality globally, further corroborating previous evidence that low education is a risk factor for adult mortality.
In this study, the protective effect of higher education on mortality was stable and did not weaken in economic contexts or with age, gender, and over time.
Thus, increasing years of schooling can help counteract growing disparities in adult mortality rates.
Continued investments in educational institutions worldwide are the need of the hour and should be viewed as investments in future public health.
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