Evidence for a biopsychosocial influence on shoulder pain: Pain catastrophizing and catechol- O -methyltransferase (COMT) diplotype predict clinical pain ratings

Abstract

The experience of pain is believed to be influenced by social, cultural, environmental, psychological, and genetic factors. Despite this assertion, few studies have included clinically relevant pain phenotypes when investigating interactions among these variables. This study investigated whether psychological variables specific to fear-avoidance models and catechol-O-methyltransferase (COMT) genotype influenced pain ratings for a cohort of patients receiving operative treatment of shoulder pain. Patients (n = 58) completed questionnaires and had COMT genotype determined preoperatively. Then, shoulder pain ratings were collected 3-5 months post-operatively. This cohort consisted of 24 females and 34 males, with mean age of 50.3 (SD = 15.0) and pre-operative pain rating of 4.5/10 (SD = 1.8). The frequency of COMT diplotypes was 34 with "high COMT activity" (LPS group) and 24 with "low COMT activity" (APS/HPS group). Preliminary analysis indicated that of all the fear-avoidance variables considered (fear of pain, kinesiophobia, pain catastrophizing, and anxiety), only pain catastrophizing was a unique contributor to clinical pain ratings. A hierarchical regression model indicated that an interaction between pain catastrophizing and COMT diplotype contributed additional variance in pre-operative pain ratings. The pain catastrophizing × COMT diplotype interaction demonstrated predictive validity as patients with high pain catastrophizing and low COMT activity (APS/HPS group) were more likely (RR = 6.8, 95% CI = 2.8-16.7) to have post-operative pain ratings of 4.0/10 or higher. Our findings suggest that an interaction between pain catastrophizing and COMT diplotype has the potential to influence pain ratings in patients seeking operative treatment of their shoulder pain.

Biopsychosocial Influence on Exercise-induced Delayed Onset Muscle Soreness at the Shoulder: Pain Catastrophizing and Catechol-O-Methyltransferase (COMT) Diplotype Predict Pain Ratings

“…47 We considered COMT genotype in this study because of its high-priority candidate rating 11 and its previous influence on pain perception for healthy participants, 13-15 and also those seeking surgical treatment for shoulder pain. 2 We did not detect a main effect for COMT genotype in the current study, however, our primary hypothesis did not involve testing main effects of COMT genotype. We were most interested in investigating whether an interaction between pain catastrophizing and COMT diplotype had the potential to influence reports of induced shoulder pain.…”

Molecular Genetics of Variability in Human Pain

“…Empirically, catastrophising is identified by heightened perception of pain (Finan et al, 2011;George et al, 2008;Edwards, 2006). The next question is whether catastrophising is caused by the same genetic factors as pain perception, or rather, if it acts on those genes to modify their influence on pain.…”

Thermal and Pressure Pain Sensitivity in Patients with Unilateral Shoulder Pain: Comparison of Involved and Uninvolved Sides

“…39,[53][54][55] As in the management of patients with low back pain, 24,27 there are ongoing efforts to improve diagnostic 35,42 and prognostic 28,29 approaches to managing patients with shoulder disorders. Currently there is an abundance of special tests and measures used to investigate shoulder pain.…”

“…29 Participants provided informed consent, in keeping with guidelines set forth by The University of tions. 9,32,38,44 Local PPT was defined as the average of the 3 shoulder measures (supraspinatus, infraspinatus, and acromion process), and distal PPT was defined as the average of the 2 nonshoulder measures (brachioradialis and masseter).…”