TORONTO - People with anxiety disorders are at increased risk of developing high blood pressure and should have their heart health carefully monitored, doctors attending the Canadian Cardiovascular Congress were told Monday.

"People with anxiety disorders are four times more likely to develop high blood pressure over one year than those of us who are anxiety-free," said Dr. Simon Bacon of the Montreal Heart Institute.

Anxiety disorders - including panic disorder, obsessive compulsive disorder and social phobia - are among the most common of all forms of mental illness, Bacon explained in a release. Those affected frequently experience intense feelings of fear and distress that are typically out of proportion to any actual danger.

Such episodes can disrupt daily functioning, including personal relationships and the ability to work.

"Anxiety can cause increases in your blood pressure and heart rate," said Dr. Brian Baker, a researcher for the Heart and Stroke Foundation. "If it is persistent, those effects could be damaging."

Bacon conducted a study that followed 185 patients with normal blood pressure for one year. Sixteen per cent of subjects had an anxiety disorder and 14 per cent had a mood disorder such as depression.

At the end of the year, 14 per cent of those with an anxiety disorder had developed high blood pressure, while just four per cent of those without such a disorder became hypertensive.

Anxiety disorders, which last at least six months, commonly occur in conjunction with other mental or physical illnesses, including depression and alcohol or substance abuse. Effective therapies exist for treating the conditions.

"One of the main messages here is that it is important to look after one's mental health as much as one's physical health," Bacon said. "If you have chronic anxious feelings, this could lead to worse heart health. There is no need to suffer - there are very good treatments out there."