[Self-rated pain sensitivity and postoperative pain]

Pain sensitivity is a risk factor for postoperative pain and is usually determined by experimental pain stimulation. Ruscheweyh et al. (Pain 146:65-74, 2009) developed the pain sensitivity questionnaire (PSQ) which assesses general pain sensitivity by self-rating without using extensive and painful experimental stimulation. The objective of this study was to examine whether subjective pain sensitivity affects postoperative pain intensity and can be considered as a risk factor for postoperative pain.

After obtaining informed consent 162 patients were enrolled in the study. Subjective pain sensitivity was assessed prior to surgery by using the PSQ. With respect to the results patients were classified into one of three groups (low, medium and high pain sensitivity). Primary outcome was postoperative pain intensity measured by numerical rating scales (NRS) on the first and second days after surgery. Other variables concerned administration of analgesics and patient satisfaction. The psychological control variables stress coping (SVF-48) as well as depression and anxiety (HADS-D) were also examined using the appropriate questionnaire.

Patients with high pain sensitivity reported significantly higher postoperative pain than patients with low pain sensitivity. This result remained significant considering negative coping styles as a covariate. Patients with high pain sensitivity reported a stronger increase of pain intensity from resting in bed to moving in bed (effect size= 1.17) as compared to patients with low pain sensitivity (effect size= 0.77). Stronger pain (NRS > 4) was reported significantly more often by patients with high pain sensitivity. Furthermore, the patient group with low pain sensitivity reported the highest satisfaction with their own health recovery.

Subjective pain sensitivity can easily be measured by the PSQ and is a risk factor for postoperative pain intensity.