Which element of the Type A behavior pattern has emerged as most important in the development of heart disease?

1. Friedman and Rosenman described Type A as an aggressive, chronic struggle to achieve more and more in less and less time, marked by competitive drive, time urgency, impatience and hostility. 2. Early work found heart disease over seven times more frequent among Type As than Type Bs, but later studies failed to replicate that overall link. 3. Researchers then asked which specific element of Type A predicts heart disease. 4. Extensive research points to the anger and hostility dimension as one of the most important factors in the development of heart disease. 5. Suppressed hostility substantially elevated heart disease risk for both men and women, and men reporting the highest anger were over six times more likely to have had a heart attack by 55. _Source: OpenStax Psychology (1st ed., CC BY 4.0), Ch 14 "Stress, Lifestyle, and Health", section 14.3 Stress and Illness_