Pain perception and psychological characteristics

Chronic pain can increase sensory sensitivity and induce the development of biased psychological characteristics such as depression. Fluctuations in sensory-related thresholds at non-injured sites (with normal peripheral tissues) in chronic pain patients are thought to be related to central sensitization, and this study analyzes the relationship between pain tolerance thresholds (PTT) at non-injured sites and psychological characteristics of chronic pain patients, and evaluates the usefulness of PTT measurement in assessing chronic pain-related morbidity. The study included the following

This study included.

PTT was measured at the uninjured site using quantitative sensory testing (QST) with electrical stimulation and classified using cluster analysis. The short form McGillPain Questionnaire was used to subjectively assess pain at the injured site. The Minnesota Multiphasic Personality Inventory (MMPI) was used to assess the psychological characteristics of the patients.

Results.

Based on the cluster analysis of the PTT, the patients were classified into a high-sensitivity group and another group consisting of the remaining patients. The results of the MMPI profile showed that the high-sensitivity group contained significantly more patients with the neurotic triad pattern and no patients with the conversion V pattern. The high-sensitivity group contained significantly more patients with the neurotic triad pattern and none with the conversion V pattern. Scores on the hypochondriac and hysteria scales were also found to be significantly lower in the high-sensitivity group than in the other groups.

Kato, F., Abe, T., Kanbara, K. et al. Pain threshold reflects psychological traits in patients with chronic pain: a cross-sectional study. BioPsychoSocial Med 11, 13 (2017). Available at: https://doi.org/10.1186/s13030-017-0098-4

Summary 

The results of this study showed that neurological traits are characteristic of patients suffering from chronic pain who have low pain tolerance. This suggests that measuring pain thresholds in the absence of pain can be useful in assessing the psychological state of chronic pain patients.

This is not something that is commonly used, but I think it is useful for medical professionals, and if I had understood the results at the time, I might have been able to be more helpful.