The type A behavior pattern and cardiovascular disease as predictors of dementia

Research has suggested that greater psychophysiological reactivity to stress increases risk of dementia and that those with the Type A behavior pattern (TABP) are predisposed to elevated stress reactivity and cardiovascular disease (CVD), but no study has evaluated the associations among TABP, CVD, and dementia, prospectively. Hence, the present study aimed to investigate dementia risk in relation to TABP and CVD.

A population-based cohort of 1,069 persons with a baseline mean age of 64.81 years from the Swedish Twin Registry was followed consecutively for up to 23 years. Based on self-reported items, TABP was measured using 6 scales: Ambition, Stress, Hard-driving, Neuroticism, Cynicism, and Paranoia. CVD was self-reported and dementia was diagnosed adhering to Diagnostic and Statistical Manual of Mental Disorders, third edition, revised (DSM-III-R) or Diagnostic and Statistical Manual of Mental Disorders, fourth edition (DSM-IV) criteria.

TABP was generally not associated with dementia risk. However, significant interaction effects of stress, paranoia, and cynicism with CVD on dementia risk were observed. That is, for those with CVD, high scores on stress, paranoia, and cynicism were associated with increased risk of dementia (hazard ratio [HR] = 1.43, 95% confidence interval [CI] = 0.95-2.15; HR = 1.39, 95% CI = 0.83-2.33; HR = 1.25, 95% CI = 0.76-2.06, respectively), whereas for those who did not have CVD, high scores on these measures appeared to be protective (HR = 0.76, 95% CI = 0.50-1.14; HR = 0.55, 95% CI = 0.34-0.89; HR = 0.50, 95% CI = 0.29-0.84, respectively).

Some features of TABP confer an increased risk for dementia in those with CVD, whereas those without CVD are protected. When evaluating the risk of dementia, CVD and personality traits should be taken into consideration.