Concordia graduate student Sonya Deschênes investigated the subject after conducting a literature review for her PhD research, supervised by psychology professor Michel Dugas. While some of the studies she came across showed that anger and anxiety were linked, she noticed that this relationship was poorly understood. "This was surprising to me because irritability, which is part of the anger family, is a diagnostic feature of Generalized Anxiety Disorder (GAD)," she explains.

GAD is a serious affliction characterized by excessive and uncontrollable worry about everyday things. It often interferes with a person's ability to function normally. Individuals suffering from GAD typically anticipate disaster, and are overly concerned about everyday issues, such as health, money, and relationships.

Deschênes and her colleagues at Concordia and Ryerson University in Toronto looked into how specific components of anger contribute to GAD. They examined hostility, physical and verbal aggression, anger expression and anger control. The team assessed more than 380 participants for GAD symptoms and their tendency to respond to anger-inducing scenarios, by testing responses to such statements as, "I strike out at whatever infuriates me" and "I boil inside, but I don't show it."

The study, which was recently published in Cognitive Behaviour Therapy, found that in the 131 participants who exhibited GAD symptoms, higher levels of anger and its various dimensions were associated with worry and anxiety. Furthermore, hostility and internalized anger contributed to the severity of their GAD symptoms.

This suggests not only that anger and anxiety go hand in hand, but also that heightened levels of anger are uniquely related to GAD status. What's more, internalized anger expression -- boiling inside without showing it -- is a stronger predictor of GAD than other forms of anger.

Deschênes acknowledges that more research is needed to understand why anger and anxiety tend to co-occur -- and she intends for her doctoral research to proceed in this direction. According to Deschênes, a possible explanation for the link is that, "when a situation is ambiguous, such that the outcome could be good or bad, anxious individuals tend to assume the worst. That often results in heightened anxiety. There is also evidence of that same thought process in individuals who are easily angered. Therefore, anger and GAD may be two manifestations of the same biased thought process."

Deschênes also argues that symptoms of anger could get in the way of the treatment for anxiety, which can be done with a technique called cognitive-behavioural therapy. "If anger and hostility are contributing to the maintenance of symptoms, and these are not targeted during treatment, these people may not be benefiting as much from that treatment," Deschênes says. "It's my hope that, by furthering our understanding of the role of anger in GAD, we can improve treatment outcomes for individuals with this disorder."