Cognitive coping style and genetic predisposition to pain sensitivity may actually play a larger role in long-lasting shoulder pain post-surgery than the size or intensity of the operation, a new University of Florida Health study concludes.
Among a group of patients who underwent shoulder surgery, those who had both a high pain sensitivity variant in a specific gene as well as worrying thoughts about pain on a questionnaire were twice as likely to still have pain one year after the surgery, the researchers found. The findings appeared in a recent issue of the journal PAIN.
The article by the UF team, which also included a psychologist, statistician, geneticist, exercise scientist and surgeons, describes two studies supported by funding from the National Institute of Arthritis and Musculoskeletal and Skin Diseases of the National Institutes of Health.
The first study was designed to help researchers learn the genetic and psychological factors that may be the best predictors of pain intensity and duration. Nearly 200 healthy participants developed a minor shoulder injury through targeted exercises and had their pain levels measured daily until pain resolved.
In the second study, researchers tested 150 patients undergoing shoulder surgery. Participants responded to two questionnaires that assessed their attitudes and beliefs about pain.
One measured fear of various painful situations, ranging from a paper cut to slamming a hand in a car door, and a second assessed what is known as pain catastrophizing, which is characterized by beliefs that pain will worsen or nothing can be done to stop it.
Participants also were tested for genes linked to pain sensitivity and inflammation. One week prior to surgery and three, six and 12 months following surgery, researchers assessed participants’ pain using a measure of pain intensity that asks respondents to rate their pain on a scale of 0 to 10, where 0 is no pain and 10 is the worst pain imaginable.
Researchers found that patients who had both a high pain sensitivity variant of the COMT gene and high levels of pain catastrophizing had a more than 40% risk of continued pain one year after surgery, compared with less than 20% among patients without those factors.
When it comes to determining which patients will have long-lasting pain after orthopedic shoulder surgery, cognitive coping style and genetic predisposition to pain sensitivity may actually be bigger factors than the size or intensity of the operation, a new University of Florida Health study finds.