Defensiveness status predicts 3-year incidence of hypertension

A growing body of research indicates that defensive personality styles (in particular, self-deception) may be related to higher resting blood pressure and stress reactivity levels. This study is the first, however, to examine the value of defensiveness as a prognostic indicator for the development of clinical hypertension.

Participants were 127 initially normotensive male and female adults who completed a comprehensive protocol including psychological testing, assessment of smoking, physical activity and body fat levels, and 8-12 h ambulatory blood pressure monitoring. Participants returned 3-years later for an identical follow-up protocol. Defensiveness was assessed using the Balanced Inventory of Desirable Responding.

At 3-year testing, 15 of 127 participants (12%) met criteria for hypertension (i.e. ambulatory mean blood pressure > 140/90). Comparisons between defensiveness groups showed that 12 of 60 (20%) high defensiveness participants met hypertension criteria, whereas only three of 67 (4.5%) low defensiveness participants were hypertensive. Logistic regression equations adjusted for age, alcohol usage, bodyfat, self-reported exercise levels, smoking, and year-1 ambulatory blood pressure, revealed that membership in the high defensiveness group was associated with more than a sevenfold risk of 3-year hypertension (adjusted risk ratio, 7.5; 95% confidence interval, 1.5-39.2).

These findings link defensive characteristics to an increased prospective risk of hypertension using state of the art ambulatory monitoring techniques, and were robust after controlling for established risk factors. We conclude that the current results add to the hypertension literature by demonstrating associations between personality and clinically relevant blood pressure criteria.