Association of cognitive function in adolescence and subsequent risk of subdural hematoma

Anna Nordström and Peter Nordström of Umea University, Sweden, report their analysis of a prospective nationwide cohort of 440,742 Swedish men in this week's PLoS Medicine, finding that reduced cognitive function in young adulthood was associated with increased risk of subdural hematoma later in life, whereas a higher level of education and physical fitness were associated with a decreased risk.

These results need to be confirmed in other large studies.

The authors say: "An exploration of the mechanistic basis for these associations might allow the construction of public health interventions aimed at reducing the population incidence of [subdural hematoma]... The present study was observational and thus inferences about causality should [...] be made with great caution. However, some of the findings in the present study may suggest a cause–effect relationship."