Background: In trauma-exposed adults, the relationship between an individual’s socioeconomic position (SEP) and post-traumatic stress disorder (PTSD) has been well demonstrated. One potential mechanism by which the stress associated with lower SEPs may impact trauma outcomes is by changes in neurocognition. In both healthy and clinical samples, area-level factors also appear to be independently related to neurocognition. Far less is known about how neighborhood socioeconomic disadvantage, may impact cognition in trauma-exposed participants. The current study employed hierarchical linear modeling to longitudinally investigate whether neighborhood disadvantage was associated with neurocognitive functioning in five domains: processing speed, sustained attention, controlled attention, cognitive flexibility, and inhibition.
Methods: One-hundred and ninety-five socioeconomically diverse traumatically-injured subjects (mean age = 32.8, 52.8% female) were recruited from an Emergency Department in southeastern Wisconsin. Two-weeks, three-months, and six-months post-trauma, participants completed self-report measures and a computerized test battery to assess neurocognitive functioning. An Area Deprivation Index (ADI) score, a measure of a neighborhood’s socioeconomic disadvantage, was derived from each participants’ home address.
Results: Greater neighborhood disadvantage was significantly related to lower scores in all the domains. Importantly, results of hierarchical linear models revealed neighborhood disadvantage was significantly associated with processing speed, controlled attention, cognitive flexibility, and inhibition across time, even after adjusting for individual annual household income, baseline PTSD symptoms, and previous adverse life experiences. This relationship was stable for all domains except sustained attention, which varied across time.
Conclusion: These results indicate neighborhood disadvantage contributes uniquely to neurocognitive functioning and, for the majority domains, these contributions are stable across time. The relationship between area-level variables and cognitive function may underlie individual vulnerability to developing psychiatric disorders. Future work should continue to examine the interaction between socioenvironmental stressors and PTSD symptoms longitudinally.
