Neuroticism modifies the association of vision impairment and cognition among community-dwelling older adults.

BACKGROUND: Vision impairment (best-corrected binocular visual acuity worse than 20/40) is a common age-related health condition requiring adaptation to maintain well-being. Whether neuroticism, a personality trait associated with decreased ability to adapt to change, modifies the association of vision impairment with worse cognition is uncertain.
METHODS: Using baseline visual acuity, neuroticism and cognitive function data from 714 community-dwelling, older participants in the Rush Memory and Aging Project, we examined whether self-reported neuroticism level modified the cross-sectional association between vision impairment and lower cognitive level.
RESULTS: Women represented 76% of the participants. The mean age was 79.6 (SD = 6.9) years and the mean education level was 14.6 (SD = 2.9) years; 26% of the participants had vision impairment. In a linear regression model adjusted for age, sex and education, each unit higher in neuroticism level worsened the association between vision impairment and lower global cognitive function level (parameter estimate for vision impairment and neuroticism interaction term = -0.017; standard error = 0.005; p = 0.001). For participants with vision impairment, a high neuroticism level (50th percentile or above) was associated with a mean global cognitive score that was 0.297 z-score units lower than for participants with a low neuroticism level (p < 0.001).
CONCLUSIONS: In older persons, neuroticism modifies the association between vision impairment and cognitive function level.