A theory that states that certain personality traits make people more susceptible to psychosomatic disorders. Among them are a tendency to emotional suppression, difficulties in expressing emotions, a tendency to perfectionism and excessive independence with a low need for support. Some personality types have been described, such as “type A,” characterized by impulsivity, aggression, and extreme competition, which has historically been associated with an increased risk of cardiovascular disease. Thus, the theory states that personality traits are not just background factors, but an active factor in the formation of physical reactions to stress.