Can health care providers recognise a fibromyalgia personality?

OBJECTIVES: To determine if experienced health care providers (HCPs) can recognise patients with fibromyalgia (FM) based on a limited set of personality items, exploring the existence of a FM personality. METHODS: From the 240-item NEO-PI-R personality questionnaire, 8 HCPs from two different countries each selected 20 items they considered most discriminative of FM personality. Then, evaluating the scores on these items of 129 female patients with FM and 127 female controls, each HCP rated the probability of FM for each individual on a 0-10 scale. Personality characteristics (domains and facets) of selected items were determined. Scores of patients with FM and controls on the eight 20-item sets, and HCPs' estimates of each individual's probability of FM were analysed for their discriminative value. RESULTS: The eight 20-item sets discriminated for FM, with areas under the receiver operating characteristic curve ranging from 0.71-0.81. The estimated probabilities for FM showed, in general, percentages of correct classifications above 50%, with rising correct percentages for higher estimated probabilities. The most often chosen and discriminatory items were predominantly of the domain neuroticism (all with higher scores in FM), followed by some items of the facet trust (lower scores in FM). CONCLUSIONS: HCPs can, based on a limited set of items from a personality questionnaire, distinguish patients with FM from controls with a statistically significant probability. The HCPs' expectation that personality in FM patients is associated with higher levels for aspects of neuroticism (proneness to psychological distress) and lower scores for aspects of trust, proved to be correct.

Correlations between within-subject variability of pain intensity reports and rubber hand illusion proprioceptive drift.

INTRODUCTION: Consistent with the Bayesian brain hypothesis, the within-subject variability of pain intensity reports as captured with the Focused Analgesia Selection Test (FAST) might be a surrogate measure of the certainty in ascending noxious signals. The outcomes of a non-pain-related task, the rubber hand illusion, were hypothesized to reflect the same construct. This study aimed to explore whether within-subject differences in variability of pain intensity reports and the outcomes of the rubber hand illusion might be related. METHODS: Nonclinical participants underwent the classic rubber hand illusion under synchronous (experimental) and asynchronous (control) conditions. Two outcomes were assessed: proprioceptive drift and feeling of ownership. Thereafter, participants underwent the FAST to assess the within-subject variability of pain reports in response to heat stimuli. Intraclass correlation (ICC) and the correlation coefficient (R2) were the main outcomes. Spearman's correlations were used to assess associations between the outcomes of the 2 tasks. RESULTS: Thirty-six volunteers completed the study. Both FAST outcomes-ICC (Spearman's r = 0.355, p = 0.033) and R2 (Spearman's r = 0.349, p = 0.037)-were positively correlated with proprioceptive drift in the synchronous but not asynchronous conditions (p > 0.05). The subjective feeling of ownership and FAST outcomes did not correlate (p > 0.05). CONCLUSIONS: The associations between the 2 tasks' outcomes imply that both tasks at least partly assess similar constructs. Current knowledge suggests that this construct represents the person's certainty in perceiving ascending sensory signals, or, in Bayesian terminology, the certainty of the likelihood.

Relations between short-term memory and the within-subject variability of experimental pain intensity reports: Results from healthy and Fibromyalgia patients.

While factors contributing to between-subjects differences in pain have been studied extensively, factors contributing to the within-subjects variability of pain reports are yet unexplored. The aim of this investigation was to assess possible associations between short-term memory and the within-subjects variability of pain reports in healthy and chronic pain patients. Healthy participants were recruited at the University of Haifa, Israel, and Fibromyalgia patients were recruited at a rheumatology department in a central hospital in Lisbon, Portugal. Following consent, both cohorts underwent the same procedures, including the digit-span test, assessing short-term memory, and the FAST procedure, assessing within-subject variability of pain intensity reports in response to experimental pain. One-hundred twenty-one healthy volunteers and 29 Fibromyalgia patients completed the study. While a significant correlation was found between the within-subjects variability and the total score of the short-term memory task (Spearman's r = 0.394, P = 0.046) in the Fibromyalgia group, a marginal correlation emerged in the healthy cohort (r = 0.174, P = 0.056). A possible interpretation of these results is that in the patients' group, at least some of the within-subjects variability of pain intensity reports might be due to error measurement derived by poorer short-term memory, rather than true fluctuations in perception.

En Pointe: Dancers Report Their Pain Less Variably Than Do Controls.

The subjective nature of pain and the lack of a gold standard for objective measurement hinders effective assessment, diagnosis, and treatment. Some individuals, such as professional dancers, are better in assessing and reporting bodily sensations. This observational study aimed to assess whether dancers report their pain less variably, than other people do. After consenting, subjects completed the focused analgesia selection test (FAST), which assesses subjects' variability of pain reports. FAST outcomes, ICC and R2 reflect the magnitude of variability of pain reports observed. In addition, subjects underwent a taste task, which similarly assesses variability of tastes (salty and sweet) intensity reports and completed the Multidimensional Assessment of Interoceptive Awareness questionnaire. Thirty-three professional dancers and 33 healthy aged-matched controls were recruited. The dancers exhibited less variability of pain reports then controls (P = .013), but not in case of tastes-reports. Years of practice was positively correlated with pain reporting variability (r = .447, P = .009, and r = .380, P = .029; for FAST ICC and R2, respectively). Multidimensional Assessment of Interoceptive Awareness subscores correlated with pain reporting variability: R2 and ICC with emotional awareness (r = .260, P = .040, and r = .274, P = .030, respectively), and R2 with trusting [r = .254, P = .044]). PERSPECTIVE: The difference between dancers and controls in the magnitude of variability of pain reports is probably due to the dancers' extensive training, which focuses on attention to body signals. Our results suggest that training can improve subjective pain reports, which are essential for quality clinical care.

No Relationships Between the Within-Subjects' Variability of Pain Intensity Reports and Variability of Other Bodily Sensations Reports.

PURPOSE: The subjective nature of pain assessment and its large variance negatively affect patient-health care provider communication and reduce the assay sensitivity of pain clinical trials. Given the lack of an objective gold standard measure, identifying the source (true or error) of the within-subject variability of pain reports is a challenge. By assessing the within-subjects variability of pain and taste reports, alongside with interoceptive measures, the current study is aimed to investigate if the ability to reliably report bodily sensations is a cross-modal characteristic. PATIENTS AND METHODS: This prospective study enrolled healthy volunteers from local universities. After consenting, subjects underwent the Focus Analgesia Selection Task (FAST), to assess within-subjects variability of pain reports in response to experimental noxious stimuli; a taste task, which similarly assesses within-subjects variability of tastes (salty and sweet) intensity reports; and the heartbeat perception task, an interoceptive task aimed to assess how accurate subjects are in monitoring and reporting their own heartbeat. In addition, all subjects completed the Multidimensional Assessment of Interoceptive Awareness (MAIA), the Perceived Stress Scale (PSS), and Hospital Anxiety and Depression Scale (HADS). Spearman's correlations were used to assess relations between all measures. RESULTS: Sixty healthy volunteers were recruited. Variability of intensity reports of different modalities were independent of each other (P > 0.05 for all correlations). The only correlation found was within modality, between variability of intensity reports of salt and sweet tastes (Spearman's r = 0.477, P < 0.001). No correlations were found between any of the task results and questionnaire results. CONCLUSION: Within-subjects variability of pain reports do not relate to variability of reports of other modalities or to interoceptive awareness. Further research is ongoing to investigate the clinical relevance of within-subjects' variability of pain reports.

Impaired Pain Modulation in Fibromyalgia Patients in Response to Social Distress Manipulation.

OBJECTIVES: Fibromyalgia (FM), a chronic pain condition, is associated with abnormalities in pain modulation. A growing body of evidence has shown that social distress modulates pain sensitivity. The current study aimed to assess the effects of social distress manipulation on pain in FM patients compared with positive (rheumatoid arthritis, RA) and negative (pain-free) controls. MATERIALS AND METHODS: FM, RA patients and pain-free controls (PFC) were recruited. Demographic, medical, and psychological data were collected. Each participant was exposed to 3 study conditions in a random order: the inclusion (positive social effects) and exclusion (negative social effects) conditions of Cyberball, a game that manipulates social distress, and a control condition. Pain sensitivity in response to nociceptive electrical and thermal (cold) stimuli was assessed before and during each study condition. RESULTS: In response to electrical stimuli, pain decreased in both the inclusion and exclusion conditions in PFC and RA groups, whereas inclusion conditions significantly increased pain in the FM group. Social manipulation (inclusion or exclusion) did not affect pain sensitivity as measured in response to thermal stimulation. DISCUSSION: These results are in line with previous studies demonstrating altered pain inhibition in FM patients, and suggest that unlike PFC or other non-"stress-related" chronic pain conditions, being socially included may increase pain perception in FM patients. Possible underlying mechanisms and clinical relevance are discussed.

Feeling Hurt: Pain Sensitivity is Correlated With and Modulated by Social Distress.

OBJECTIVES: Social distress, resulting from loss or threat to social relationships, shares similar psychological and neuronal processes with physical pain. Recent evidence demonstrated that social distress may have an impact on pain. The current study aimed to further assess the relationship between these 2 phenomena. MATERIALS AND METHODS: Sixty healthy participants were randomly assigned to inclusion, noninclusion, or exclusion conditions of Cyberball, a virtual ball tossing game used to induce social distress. Pain and unpleasantness in response to noxious electrical stimuli were assessed before and after Cyberball manipulation. Psychological characteristics were evaluated by the Experiences in Close Relationships Questionnaire and the neuroticism scale of Big Five Inventory. RESULTS: Significant correlations were found between social distress and pre-Cyberball unpleasantness thresholds: those who perceived the Cyberball task as more distressing demonstrated lower unpleasantness thresholds. Post-Cyberball manipulation pain intensity ratings, but not unpleasantness ratings, were lower in the inclusion condition. No associations were found between the psychological characteristic and the effects of Cyberball on pain or unpleasantness ratings. DISCUSSION: The current study results indicate that participants' pre-Cyberball unpleasantness threshold is related to their responsiveness to social distress and that physical pain may be modulated by social events. Further studies are needed to clarify the clinical relevance of these results.