PT  - JOURNAL ARTICLE
AU  - Giovanni Veronesi
AU  - Frank Kee
AU  - Blanaid Hicks
AU  - Hannah Forrest
AU  - Hugh Tunstall-Pedoe
AU  - Kari Kuulasmaa
AU  - Susana Sans
AU  - Veikko Salomaa
AU  - Barbara Thorand
AU  - Augusto Di Castelnuovo
AU  - Stefan Soderberg
AU  - Giancarlo Cesana
AU  - Martin Bobak
AU  - Roberto De Ponti
AU  - Licia Iacoviello
AU  - Luigi Palmieri
AU  - Tanja Zeller
AU  - Stefan Blankenberg
AU  - Marco M Ferrario
TI  - Decomposing the educational gradient in allostatic load across European populations. What matters the most: differentials in exposure or in susceptibility?
AID  - 10.1136/jech-2020-213946
DP  - 2020 Dec 01
TA  - Journal of Epidemiology and Community Health
PG  - 1008--1015
VI  - 74
IP  - 12
4099  - http://jech.bmj.com/content/74/12/1008.short
4100  - http://jech.bmj.com/content/74/12/1008.full
SO  - J Epidemiol Community Health2020 Dec 01; 74
AB  - Background We investigate whether socially disadvantaged individuals are more susceptible to the detrimental effects of smoking and alcohol intake on allostatic load (AL), a marker of physiological ‘wear and tear’, resulting from adaptation to chronic stress.Methods In a cross-sectional analysis, 27 019 men and 26 738 women aged 35–74 years were identified from 21 European cohorts in the BiomarCaRE consortium. We defined three educational classes (EDs) according to years of schooling and an AL score as the sum of z-scores of eight selected biomarkers from the cardiovascular, metabolic and inflammatory systems. We used the Oaxaca-Blinder decomposition to disentangle the ED gradient in AL score into the differential exposure (DE, attributable to different distribution of smoking and alcohol intake across EDs) and the differential susceptibility (DS, attributable to a different effect of risk factors on AL across EDs) components.Results Less-educated men (mean AL difference: 0.68, 95% CI 0.57 to 0.79) and women (1.52, 95% CI 1.40 to 1.64) had higher AL scores. DE accounted for 7% and 6% of the gradient in men and women, respectively. In men, combining smoking and alcohol intake, DS accounted for 42% of the gradient (smoking DS coefficient=0.177, 26% of the gradient; alcohol DS coefficient=0.109; 16%, not statistically significant). DS contribution increased to 69% in metabolic markers. DS estimates were consistent across age groups, irrespective of comorbidities and robust to unmeasured confounding. No DS was observed in women.Conclusions In men, a DS mechanism substantially contributes to the educational class gradient in allostatic load.