GAD is much more than normal anxiety or worry that most people experience from time to time. The chronic anxiety, worry or tension of GAD disrupts a person's life and often leads to further emotional and physical difficulties. A person with GAD may worry about health, money, family or work, but the source of anxiety may not always be easy to find. Even waking up and facing the day might cause overwhelming anxiety. People with GAD are often aware that their worrying is exaggerated, but they still cannot stop doing it.
The chronic anxiety of GAD may lead to sleep difficulties, muscle tension, trembling, twitching, headaches, irritability, sweating, hot flashes, lightheadedness, breathing problems, nausea, difficulty concentrating, lump in the throat, and a frequent need to use the bathroom. Conditions such as depression, substance abuse, other anxiety disorders, irritable bowel syndrome, sleep disorders, and chronic headaches often coexist with GAD.
"Because the symptoms of GAD are so severe and incapacitating and take a much larger toll than everyday anxiety, long-term treatment may optimize a person's chances of not only controlling their symptoms, but achieving the optimal goal of treatment -- remission -- the virtual elimination of symptoms," said Christer Allgulander, MD, Associate Professor of Psychiatry at Karolinska Institute, in a press release.
Cognitive-behavior therapy and medication are the two most widely used treatments for GAD. Benzodiazepines and Buspar are the medications usually used to treat GAD, but researchers continue to search for helpful medications which will provide long-term relief with the fewest side effects. Venlafaxine is a dual reuptake inhibitor antidepressant which affects both sertonin and norepinephrine, neurotransmitters believed to be associated with anxiety and depression.
The researchers at Karolinska Institute sought to find out if venlafaxine ( Effexor ) would be a viable long-term treatment for GAD. The study participants were 541 patients from 55 European sites who had been diagnosed with GAD based on DSM-IV criteria. Most participants suffered from chronic GAD; on average, participants had been strugging with the condition for 10 years.
Researchers compared three doses of venlafaxine extended-release (37.5 mg, 75 mg, and 150 mg) with a placebo over a six-month period. To determine the efficacy of the dosage, researchers used several anxiety rating scales, most particularly the Hamiliton Rating Scale for Anxiety (HRSA). The HRSA is a widely used scale which measures 14 items on a 5-point scale with 0 as "anxiety not present" and 4 as "severe anxiety."
After six months of treatment, patients given 75 mg and 150 mg of venlafaxine showed significant changes on the HRSA. Patients taking 75 mg showed a mean change of 15.5 while patients taking 150 mg showed a mean change of 16.4. Those on the placebo showed a mean change of 11.0. Patients taking venlafaxine also showed improved social functioning as measured by the Self-Rated Social Adjustment Scale. The study also found that venlafaxine extended-release provides symptom relief by the second week of treatment.
"This study shows that venlafaxine extended-release is effective for use over the long term, giving patients the best chance to return to their normal range of functioning," Allgulander said.
Reference: Allgulander C, Hackett D, Salinas E (2001). Venlafaxine extended release (ER) in the treatment of generalised anxiety disorder: twenty-four-week placebo-controlled dose-ranging study. Br J Psychiatry 179:181.
