Phobic anxiety and cognitive performance over 4 years among community-dwelling older women in the Nurses' Health Study.

OBJECTIVE: To examine the relation of phobic anxiety to late-life cognitive trajectory.
DESIGN: Prospective cohort.
SETTING: Nurses' Health Study-U.S. registered nurses. PARTICIPANTS: A total of 16,351 women among whom phobic anxiety symptoms were assessed in 1988 (mean age = 63 years). MEASUREMENTS: Beginning a decade after phobic anxiety ascertainment (mean age = 74 years), three assessments of general cognition, word and paragraph immediate and delayed recall, category fluency, and attention or working memory were administered over an average of 4.4 years; global cognitive and verbal memory composite scores were generated from the component tests. General linear models of response profiles were used to evaluate relations of phobic anxiety to initial cognitive performance and subsequent change.
RESULTS: Higher phobic anxiety was associated with poorer initial performance: for example, comparing women with the highest anxiety to those with no or minimal symptoms, the multivariate-adjusted mean difference (95% confidence interval) in scores was -0.10 (-0.13,-0.06) standard units for the global score summarizing all tests, and -0.08 (-0.11,-0.04) standard units for verbal memory (summarizing four word- and paragraph-recall tasks). Mean differences between extreme categories of phobic anxiety were equal to those for participants aged 1.5-2 years apart: that is, cognitively equivalent to being about 2 years older. There were no relations of phobic anxiety to subsequent cognitive change.
CONCLUSIONS: Higher mid-life phobic anxiety was related to worse later-life overall cognition and verbal memory. Yet, profiles of poorer cognition with higher anxiety remained parallel over time, suggesting phobic anxiety may impose impact on cognition earlier in life, rather than ongoing impact in later-life.