Sub-Grouping Healthy Subjects’ Sensitivity to Pain and Its Relationship to Personality Traits: Results of a Cluster Analysis

Abstract

Objective: Individual differences in the sensitivity to pain and the factors that may contribute to these differences are well studied. Nevertheless, there is no single test that can reliably classify subjects as being sensitive or insensitive to pain. Methods: In the present study, hierarchical clustering and K-means cluster analysis was used to identify subgroups among 191 healthy subjects (105 females, 86 males) according to their sensitivity to pain. Group determination was based on the subjects' response to experimental noxious stimuli of heat (pain intensity), cold (cold pain threshold, tolerance, and intensity), and conditioned pain modulation (CPM, tested by co-administering repeated short painful heat stimuli and a conditioning tonic cold pain stimulation). In addition, in order to determine if the subjects in these subgroups differed on personality traits scores on Cloninger's Tridimensional Personality Questionnaire (TPQ, outcome measure) for the three dimensions of personality: Novelty Seeking (NS); Harm Avoidance (HA); and Reward Dependence (RD) were calculated. Results: Based on pain scores, subjects were grouped as low pain (57%) with a low level of sensitivity in pain parameters, or high pain (43%) cluster members. The high pain had significant higher scores of HA (p = 0.05) and RD (p = 0.05) than the low pain group. Conclusions: This method of sub-grouping may be useful for identifying the mechanisms underlying individual variability in the sensitivity to pain and may point to groups at risk for experiencing high levels of clinical pain.

Multi-sensory Responsiveness and Personality Traits Predict Daily Pain Sensitivity

“…It seems that Openness-to-Experience could serve as the opposite anchor of harm avoidance. Notably, while Pud et al (2014) tested the relation between pain sensitivity and personality dimensions in the lab, our findings not only support their results, but have the additional advantage of being able to be extrapolated to environments outside the lab.…”

“…In the present study, Neuroticism was found to have the strongest correlations (among all five personality traits) to all three daily pain sensitivity measures. While Neuroticism is characterized by tenseness, moodiness, and anxiety (Martínez et al, 2011;Littman-Ovadia and Lavy, 2012), it is the trait most similar to harm avoidance (Pud et al, 2014). Openness-to-Experience, which this study found negatively correlated to daily pain sensitivity, denotes having wide interests and being imaginative and insightful (Littman-Ovadia and Lavy, 2012).…”

“…This study demonstrates that when examining the association between personality traits and daily pain sensitivity, the subscales of Neuroticism (positive correlation) and Openness-to-Experience (negative correlation) were found significantly associated. Pud et al (2014) sub-grouped healthy individuals according to different pain modality sensitivities and personality profiles, and found that the personality trait of harm avoidance was the most likely to determine pain perception. Harm avoidance, according to Cloninger's Tridimensional Personality Theory, is defined as a tendency to respond intensely to previously established signals of aversive stimuli and to passively avoid novelty (Paine et al, 2009).…”

“…There is substantial individual variability in the perception of experimental and clinical pain, as well as in the susceptibility in developing painful conditions, and responding to pain-relieving treatments (Mogil, 1999;Pud et al, 2004Pud et al, , 2006. Continuous efforts have been devoted to identifying factors relevant to understanding this variability (Pud et al, 2004(Pud et al, , 2014Vassend et al, 2013). Increasing evidence indicates that genetic factors (Young et al, 2012;Vassend et al, 2013), demographic characteristics (e.g., age, sex, ethnicity) and personality traits (Riley and Wade, 2004;Pud et al, 2004)-the prompts to think or act in a similar way in response to varied stimuli or situations (Goldberg, 1990), are all related to pain responses.…”

Identification of clusters of individuals relevant to temporomandibular disorders and other chronic pain conditions

“…4,10,11,21,23,29,33–35,45,53,60,68,69,72 Among these, the Multidimensional Pain Inventory 33 (MPI) is probably the best known. The MPI emerged from biopsychosocial theory, and studies assessing outcomes based on MPI classification indicate that anatomically distinct disorders (headache, TMD, back pain) respond to treatments similarly within each cluster.…”