Facial expression of pain: an evolutionary account.

This paper proposes that human expression of pain in the presence or absence of caregivers, and the detection of pain by observers, arises from evolved propensities. The function of pain is to demand attention and prioritise escape, recovery, and healing; where others can help achieve these goals, effective communication of pain is required. Evidence is reviewed of a distinct and specific facial expression of pain from infancy to old age, consistent across stimuli, and recognizable as pain by observers. Voluntary control over amplitude is incomplete, and observers can better detect pain that the individual attempts to suppress rather than amplify or simulate. In many clinical and experimental settings, the facial expression of pain is incorporated with verbal and nonverbal vocal activity, posture, and movement in an overall category of pain behaviour. This is assumed by clinicians to be under operant control of social contingencies such as sympathy, caregiving, and practical help; thus, strong facial expression is presumed to constitute and attempt to manipulate these contingencies by amplification of the normal expression. Operant formulations support skepticism about the presence or extent of pain, judgments of malingering, and sometimes the withholding of caregiving and help. To the extent that pain expression is influenced by environmental contingencies, however, "amplification" could equally plausibly constitute the release of suppression according to evolved contingent propensities that guide behaviour. Pain has been largely neglected in the evolutionary literature and the literature on expression of emotion, but an evolutionary account can generate improved assessment of pain and reactions to it

How Do We Understand Depression in People with Persistent Pain?

Depression and depressed mood are common in people with persistent (chronic) pain, exacerbating disability and worsening quality of life. Yet the relationship between persistent pain and depression remains unclear, despite its importance for designing or adapting interventions to address both pain and depression. Meta-analysis of cognitive and behavioral interventions designed for rehabilitation of persistent pain shows small benefits for distress. However, substantial variation between studies in patients’ baseline levels of depression and in quality of treatments militates against any clear conclusions. Apart from these interventions, longitudinal studies on chronic pain and depression in adults from clinical populations provide weak evidence that depression worsens pain outcomes. We systematically searched for and reviewed 14 longitudinal studies that explored the association between persistent pain and depression, aiming to identify: (1) the effects on pain of baseline depression; (2) the effects on depression of baseline pain; and (3) possible mediating variables, with particular attention to methodology. Unfortunately, most studies used unsuitable instruments to measure depression, and we could draw only tentative conclusions about effects over time. Better models and clearer measurement strategies are required for a next generation of clinically useful treatment trials and, meanwhile, some implications for treatment are explored

Impact of pain and postoperative complications on patient-reported outcome measures 5 years after microvascular decompression or partial sensory rhizotomy for trigeminal neuralgia

BACKGROUND: Microvascular decompression (MVD) and partial sensory rhizotomy (PSR) provide longstanding pain relief in trigeminal neuralgia (TN). Given their invasiveness, complications can result from such posterior fossa procedures, but the impact of these procedures and their complications on patient-reported outcome measures (PROM), such as quality of life and distress, are not well established. METHOD: Five years after surgery, patients who underwent first MVD or PSR for TN at one institution, between 1982 and 2002, were sent a self-completion assessment set containing a range of PROMs: the Short Form-12 (SF-12) questionnaire to assess quality of life, the Hospital Anxiety and Depression Scale (HADS) to assess distress, and a questionnaire containing questions about postoperative complications, their severity and impact on quality of life. These findings and demographic data were compared between MVD and PSR. RESULTS: One hundred and eighty-one of 245 (73.9%) patients after first MVD and 49 of 60 (81.7%) after PSR responded, and were included in analyses. The mean SF-12 scores of patients after MVD and PSR at five-year follow-up were significantly lower than English age-matched norms. Though there were no differences in SF-12 physical or mental component scores between the two procedures, patients after PSR were more likely to have case-level anxiety (RR = 3.3; 95% CI, 1.1-10.5; p = 0.03), had more postoperative complications, and of greater severity, including pain (RR = 2.52; 95% CI, 1.5-4.1; p < 0.001), numbness (RR = 5.9; 95% CI, 3.8-9.2; p < 0.001), burning sensations (RR = 3.0; 95% CI, 1.5-5.8; p = 0.001) and difficulty in eating (RR = 17.1; 95% CI, 5.6-53.1; p < 0.001), and these had a larger impact on quality of life for PSR compared to MVD. CONCLUSIONS: The quality of life 5 years after MVD or PSR is poorer than in the general population and associated with postoperative complications such as pain, numbness, burning sensation and difficulty in eating. These complications are commoner after PSR than MVD, and this is associated with anxiety in PSR patients at five-year follow-up. However, these differences are not reflected by quality of life scores. Outcome measures need to incorporate patient experience after treatment for TN, and represent patient priorities for quality of life

Effectiveness of psychological interventions for chronic pain on health care use and work absence: systematic review and meta-analysis

Psychological interventions for chronic pain and its consequences have been shown to improve mood, disability, pain, and catastrophic thinking, but there has been no systematic review specifically of their effects on health care use or time lost from work as treatment outcomes in mixed chronic pain. We conducted a systematic review and meta-analysis to evaluate the effectiveness of psychological therapies for chronic pain (excluding headache) in adults for these outcomes. We used searches from two previous systematic reviews and updated them. Eighteen randomized controlled trials were found that reported health care use (15 studies) and work loss (nine studies) as outcomes. Fourteen studies provided data for meta-analysis. There were moderate effects for psychological interventions compared to active, treatment as usual and waiting list controls in reducing health care use, with confidence in the findings. No benefits were found for medication reduction, but with less confidence in this result. Analysis of work loss showed no significant effects of psychological interventions over comparisons, but the use of many different metrics necessitated fragmenting the planned analyses, making summary difficult. The results are encouraging for the potential of routine psychological intervention to reduce post-treatment health care use, with associated cost savings, but it is likely that the range and complexity of problems affecting work necessitate additional intervention over standard group psychological intervention

Special Considerations for the Treatment of Pain from Torture and War

Pain care for survivors of torture and of war shows similarities and marked differences. For both, pain can be complex with unfamiliar presentations and the pains hard to assign to known disorders. For many survivors, pain and associated disability are overshadowed by psychological distress, often by post-traumatic stress symptoms that can be frightening and isolating. Pain medicine in war can exemplify best techniques and organisation, reducing suffering, but many military veterans have persistent pain that undermines their readjustment. By contrast, survivors of torture rarely have any acute health care; their risk for developing chronic pain is high. Even when settled as refugees in a well-resourced country, their access to healthcare may be restricted. Recent evidence is reviewed that informs assessment and treatment of pain in both groups, with the broader context of psychological distress addressed at the end. Clinical and research implications are briefly outlined

Pulse-Administered Toceranib Phosphate Plus Lomustine for Treatment of Unresectable Mast Cell Tumors in Dogs.

BackgroundNonresectable mast cell tumors (MCT) in dogs remain a therapeutic challenge, and investigation of novel combination therapies is warranted. Intermittent administration of tyrosine kinase inhibitors (TKI) combined with cytotoxic chemotherapy may effectively chemosensitize canine MCT while decreasing cost and adverse effects associated with either agent administered as monotherapy.Hypothesis/objectivesThe primary study objectives were to (1) identify the maximally tolerated dose (MTD), (2) determine the objective response rate (ORR) and (3) describe the adverse event profile of pulse-administered toceranib phosphate (TOC) combined with lomustine.AnimalsForty-seven client-owned dogs with measurable MCT.MethodsToceranib phosphate was given PO on days 1, 3 and 5 of a 21-day cycle at a target dosage of 2.75 mg/kg. Lomustine was given PO on day 3 of each cycle at a starting dosage of 50 mg/m(2) . All dogs were concurrently treated with diphenhydramine, omeprazole, and prednisone.ResultsThe MTD of lomustine was established at 50 mg/m(2) when combined with pulse-administered TOC; the dose-limiting toxicity was neutropenia. Forty-one dogs treated at the MTD were evaluable for outcome assessment. The ORR was 46% (4 complete response, 15 partial response) and the overall median progression-free survival (PFS) was 53 days (1 to &gt;752 days). On multivariate analysis, variables significantly associated with improved PFS included response to treatment, absence of metastasis, and no previous chemotherapy.Conclusions and clinical importanceCombined treatment with pulse-administered TOC and lomustine generally is well tolerated and may be a reasonable treatment option for dogs with unresectable or metastatic MCT