Systemic inflammation measured by erythrocyte sedimentation rate and cognitive function among young men in Sweden: A within-sibling analysis

This study assesses the extent to which the association between erythrocyte sedimentation rate, a marker of inflammation, and cognitive function is explained by shared familial factors using within-sibling analyses. Men who were born in Sweden between 1950 and 1965 and recorded in the Swedish Military Conscription Register between 1969 and 1983 were included (N = 632,396). Erythrocyte sedimentation rate and cognitive function were measured at the conscription assessment (median age = 18.3 years, with a range from 15.5 to 28.5 years). Conventional linear regression and multilevel linear regression with a hybrid modeling approach were used, with the latter to obtain within-effect estimation in which unmeasured familial confounding shared by siblings was controlled for. We found that the association between erythrocyte sedimentation rate and cognitive function at conscription assessment was partly accounted for by, but remained independent of, shared familial factors.

Automated summary

This study examines the relationship between erythrocyte sedimentation rate (ESR), a marker of inflammation, and cognitive function, and investigates the potential influence of shared familial factors. The study includes men born in Sweden between 1950 and 1965 and registered in the Swedish Military Conscription Register between 1969 and 1983 (N = 632,396). ESR and cognitive function were measured at the time of conscription assessment, with analysis conducted using conventional linear regression and multilevel linear regression to control for familial confounding. The findings suggest that while shared familial factors account for some of the association between ESR and cognitive function, there remains an independent relationship.