Relations between pain, anxiety, mood and muscle tension in chronic pain patients. A correlation study.

The relationship between psychological variables, particularly depressed mood and anxiety, and pain has received a good deal of attention. In this study, 16 chronic pain patients rated their mood, anxiety level, pain, muscle tension, and reclining time daily over a period of about 6 weeks. Correlations were calculated for each combination of variables for each individual patient. The results indicated a good deal of variability between patients. The majority of patients did have significant correlations for pain vs. mood, pain vs. anxiety, pain vs. reclining time, anxiety vs. muscle tension, anxiety vs. mood, and reclining time vs. mood. However, the size of the correlations was sometimes small, and some patients even occasionally had correlations in the opposite direction of that predicted. Overall, the data suggest that psychological variables are related to the experience of chronic pain, but that the size of the relationship may be smaller than previously thought. Furthermore, the high degree of individual variability needs to be stressed.