The new research was published in General Hospital Psychiatry.
"I think (health care) providers are more aware of the common occurrence of depression in patients with chronic pain, and there has been less of an emphasis on anxiety," said lead author Kurt Kroenke, M.D., professor of medicine at Indiana University in Indianapolis.
In the new study, researchers evaluated 250 primary care patients who were being treated at a Veterans Medical Center in the Midwest. All patients had moderate to severe chronic joint or back pain that had lasted at least 3 months despite trying pain medications.
The participants were screened for five common anxiety disorders: generalized anxiety, characterized by persistent worry; panic, or sudden, repeated attacks of fear; social anxiety, characterized by overwhelming anxiety in everyday social interactions; post-traumatic stress, or a repeated feeling of danger after a stressful event; and obsessive-compulsive disorder, characterized by repeated thoughts or rituals that interfere with daily life. They were also screened for health-related quality of life issues, such as fatigue, sleep habits, and work productivity.
The study found that 45 percent of the pain patients screened positive for at least one or more of the common anxiety disorders. And those who had an anxiety disorder also reported significantly worse pain and health-related quality of life than patients without a disorder.
"It is important to note that patients in our study screened positive for an anxiety disorder but not all would have a full-blown anxiety disorder if they had a diagnostic psychiatric interview," said Kroenke. "Some may just have anxiety symptoms and not all would warrant active treatment. However, probably at least 1 in 5 might have some type of anxiety disorder."
The researchers also found that it was common for the five different types of anxiety conditions to occur in combination with each other and with depression.
"Psychological comorbidities are common in patients with chronic low back pain and other studies have also shown a high prevalence of depression, anxiety and other psychological conditions," said pain expert Roger Chou, M.D., an assistant professor of medicine at Oregon Health & Science University.
Chou added that the guidelines on evaluating and managing lower back pain do recommend clinicians assess patients for psychological factors that may be contributing to a poorer prognosis and address them with appropriate treatments.
"Many patients benefit from cognitive behavioral therapy to help them in coping with the pain and related anxiety," Chou continued. "Just throwing pain medications at someone like this doesn't tend to be very effective since you're not dealing with an important driver of the pain."