Exploring Socioeconomic Disparities: The Association between the Mediterranean Lifestyle and Mortality across Education and Income Levels in the Prospective Lifelines Cohort.
Abstract
Background
There is little investigation into how traditional lifestyles associate with health and whether this association differs over levels of socioeconomic status.
Objective
To assess the association between a Mediterranean lifestyle and all-cause mortality across socioeconomic levels.
Methods
We analyzed data from 105,812 adult participants from the Lifelines cohort, followed from 2006-2013 to 2025. The MEDLIFE index includes 23 lifestyle items-including food consumption, dietary habits, physical activity, rest, and social habits-which score 1 point to indicate adherence at baseline. Income and education were self-reported at baseline and divided in three progressive levels, and we created a composite with both. Deaths were retrieved from death records. To study the associations, we used multivariable Cox models, estimating hazard ratios (HR) and 95% confidence intervals (95% CI), adjusted for general, lifestyle and clinical risk factors
Results
After a median follow-up of 13.25 years, 3,976 deaths occurred. An inverse dose-response relationship was observed between MEDLIFE adherence and mortality: after full adjustment, participants in the highest quartile had a HR (95% CI) of 0.70 (0.64, 0.77) compared to the lowest quartile. A healthy Mediterranean lifestyle was associated with reductions in risk among both the most disadvantaged groups and more educated or affluent categories. In joint analyses, differences in income changed the association of MEDLIFE with mortality risk more than differences in education: HR (95% CI) for highest MEDLIFE adherence and income was 0.54 (0.46, 0.63) while highest adherence and education was 0.67 (0.57, 0.78).
Conclusions
Higher adherence to the MEDLIFE index was linked to lower all-cause mortality across all socioeconomic levels, with income being the strongest modifier of this association. Poor lifestyle increased mortality similarly in adults with high and low education. Our findings suggest that healthy lifestyles could mitigate socioeconomic mortality gaps, promoting the Mediterranean lifestyle as an effective public health strategy.