Validation of the short-form McGill pain questionnaire-2 in younger and older people with cancer pain.

Unlabelled: Pain is among the most common symptoms of cancer. Because cancer can occur at any age, it is imperative that pain assessment tools are valid for use across the adult lifespan. The Short-Form McGill Pain Questionnaire-2 (SF-MPQ-2) is a valid and reliable tool for the assessment of the multidimensional qualities of pain in people with chronic nonmalignant pain, but its psychometric properties in people with cancer pain and in older versus younger people require investigation.

Pain.

Pain has many valuable functions. It often signals injury or disease, generates a wide range of adaptive behaviors, and promotes healing through rest. Despite these beneficial aspects of pain, there are negative features that challenge our understanding of the puzzle of pain, including persistent phantom limb pain after amputation or total spinal cord transection.

Development and initial validation of an expanded and revised version of the Short-form McGill Pain Questionnaire (SF-MPQ-2).

The objective of the present research was to develop a single measure of the major symptoms of both neuropathic and non-neuropathic pain that can be used in studies of epidemiology, natural history, pathophysiologic mechanisms, and treatment response. We expanded and revised the Short-form McGill Pain Questionnaire (SF-MPQ) pain descriptors by adding symptoms relevant to neuropathic pain and by modifying the response format to a 0-10 numerical rating scale to provide increased responsiveness in longitudinal studies and clinical trials. The reliability, validity, and subscale structure of the revised SF-MPQ (SF-MPQ-2) were examined in responses from 882 individuals with diverse chronic pain syndromes and in 226 patients with painful diabetic peripheral neuropathy who participated in a randomized clinical trial.

Evolution of the neuromatrix theory of pain. The Prithvi Raj Lecture: presented at the third World Congress of World Institute of Pain, Barcelona 2004.

The neuromatrix theory of pain proposes that pain is a multidimensional experience produced by characteristic "neurosignature" patterns of nerve impulses generated by a widely distributed neural network-the "body-self neuromatrix"-in the brain. These neurosignature patterns may be triggered by sensory inputs, but they may also be generated independently of them. Acute pains evoked by brief noxious inputs have been meticulously investigated by neuroscientists, and their sensory transmission mechanisms are generally well understood.

The psychological assessment of candidates for spinal cord stimulation for chronic pain management.

It is known that, in spite of meeting appropriate clinical criteria for spinal cord stimulation (SCS) and having undergone flawless procedures, a significant number of patients who fail the therapy continues to exist. It is the purpose of this article to focus on the development of psychosocial indicators of success for SCS, if any. Referring to specialist literature authors present a review of what is known, what is not known, and what remains controversial on this topic.

Inflammation-susceptible Lewis rats show less sensitivity than resistant Fischer rats in the formalin inflammatory pain test and with repeated thermal testing.

Comparisons between Lewis and Fischer inbred strains of rats are used frequently to study the effect of inherent differences in function of the hypothalamic-pituitary-adrenal axis on pain-relevant traits, including differential susceptibility to chronic inflammatory disease and differential responsiveness to analgesic drugs. Increasing use of genetic models including transgenic knockout mice and inbred strains of rodents has raised our awareness of, and the importance of, thorough characterization (or phenotyping) of the strains of rodents being compared. Furthermore, genetic variability in analgesic sensitivity is correlated with, and may be caused by, genetically determined baseline sensitivity.

Age-related differences in the qualities but not the intensity of chronic pain.

Age differences in the experience of chronic pain remain unclear. A serious barrier to progress in the field of pain and aging arises from the lack of data regarding the psychometric properties of pain scales for use with the elderly. The present study was designed to assess age differences in pain intensity and quality and to compare the psychometric properties of the McGill Pain Questionnaire (MPQ) in young and elderly chronic pain patients.

Central neuroplasticity and pathological pain.

The traditional specificity theory of pain perception holds that pain involves a direct transmission system from somatic receptors to the brain. The amount of pain perceived, moreover, is assumed to be directly proportional to the extent of injury. Recent research, however, indicates far more complex mechanisms.

Pain and the neuromatrix in the brain.

The neuromatrix theory of pain proposes that pain is a multidimensional experience produced by characteristic "neurosignature" patterns of nerve impulses generated by a widely distributed neural network-the "body-self neuromatrix"-in the brain. These neurosignature patterns may be triggered by sensory inputs, but they may also be generated independently of them. Acute pains evoked by brief noxious inputs have been meticulously investigated by neuroscientists, and their sensory transmission mechanisms are generally well understood.

Blocking NMDA receptors in the hippocampal dentate gyrus with AP5 produces analgesia in the formalin pain test.

The hippocampus is an integral component of the "limbic" system and, as such, may contribute to the negative affect and avoidance motivation experienced during pain. A substantial body of evidence indicates that the hippocampus processes pain-related information, that some hippocampal neurons respond exclusively to painful stimulation, and that long-term anatomical changes occur in dentate gyrus neurons, following noxious physical stimulation. NMDA receptor antagonist drugs administered to the hippocampus interfere with long-term potentiation, learning, and memory; these same drugs, when applied to the spinal cord, prevent the long-term neurophysiological changes caused by noxious physical stimulation.

Age differences in nociception and pain behaviours in the rat.

Much remains to be learned about the effects of ageing on pain. Studies of life-span changes in nociception and pain behaviours in the rat are equivocal making it difficult to draw firm conclusions. This paper reviews the available data and finds that age differences in nociception may be dependent on the pain test employed.

Nausea and vomiting during pregnancy: A prospective study of its frequency, intensity, and patterns of change.

Objective: Our purpose was to provide a detailed description of patterns of nausea and vomiting of pregnancy.

Study Design: A prospective study was performed with 160 women who provided daily recordings of frequency, duration, and severity of nausea and vomiting.

Results: Seventy-four percent of women reported nausea lasting a mean of 34.

Age differences in the response to the formalin test in rats.

We report the results of a study designed to assess age differences in the response to the formalin test, a model of tissue injury and inflammation, while controlling for differences in weight and motoric abilities in three groups of adult male Long-Evans rats: young (3 months old), middle-aged (18 months old), and old (24 months old). The first part of the study assessed initial differences in responsivity and found that the middle-aged group showed the greatest response, whereas the young and old groups did not differ from each other. In the second part of the study, the young and middle-aged animals were followed for a 4-month period.

Long-term patterns of morphine dosage and pain intensity among cancer patients.

Cancer pain remains a worldwide problem and some patients continue to be undermedicated because of concerns about tolerance and drug dependence. The aim of this study was to document the morphine intake of patients with chronic cancer pain in an inpatient palliative care unit and to describe the long-term pattern of morphine use and pain intensity in this patient population. With IRB approval and written informed consent, patients admitted over a 64-week period to the palliative care unit at the Royal Victoria Hospital, Montreal, were candidates for this study.

The role of corticotropin-releasing factor in pain and analgesia.

Corticotropin-releasing factor (CRF) is a peptide that is released from the hypothalamus and in widespread areas of the brain following exposure to stressors. It is considered to be a mediator of many of the effects of stress, and its analgesic properties have been demonstrated in many studies. However, for primarily methodological reasons, the effects of CRF in the central nervous system have been neglected whereas the peripheral effects of CRF have been overemphasized.

Pain--an overview.

The neuromatrix theory of pain proposes that pain is a multidimensional experience produced by characteristic "neurosignature" patterns of nerve impulses generated by a widely distributed neural network--the "body-self neuromatrix"--in the brain. These neurosignature patterns may be triggered by sensory inputs, but they may also be generated independently of them. Pains that are evoked by noxious sensory inputs have been meticulously investigated by neuroscientists, and their sensory transmission mechanisms are generally well understood.

From the gate to the neuromatrix.

The gate control theory's most important contribution to understanding pain was its emphasis on central neural mechanisms. The theory forced the medical and biological sciences to accept the brain as an active system that filters, selects and modulates inputs. The dorsal horns, too, were not merely passive transmission stations but sites at which dynamic activities (inhibition, excitation and modulation) occurred.

A case of referred pain evoked by remote light touch after partial nerve injury.

An unusual case of referred pain is presented in which a 63-year-old man, who suffered a severe injury to his right hand and arm during young adulthood, describes the later development of dysesthesia and shooting pain in his arm subsequent to stimulation of the ipsilateral scalp, the temporal and infrazygomatic region of the face, and the back. Referred sensations of this type are usually reported following amputation of an arm. Clinical examination of the sensory and motor function of the arm and hand revealed partial damage to the radial, ulnar and median nerves as well as possible brachial plexus involvement.

Measurement of pain.

Pain is a personal, subjective experience influenced by cultural learning, the meaning of the situation, attention, and other psychologic variables. Approaches to the measurement of pain include verbal and numeric self-rating scales, behavioral observation scales, and physiologic responses. The complex nature of the experience of pain suggests that measurements from these domains may not always show high concordance.

Pain: an overview.

Until the 1960s, pain was considered an inevitable sensory response to tissue damage. There was little room for the affective dimension of this ubiquitous experience, and none whatsoever for the effects of genetic differences, past experience, anxiety, or expectation. In recent years, great advances have been made in our understanding of the mechanisms that underlie pain and in the treatment of people who complain of pain.

Potentiation of opioid analgesia by psychostimulant drugs: a review.

Recent research has investigated drug combinations that enhance the analgesic effectiveness of their component substances. Many studies have examined the combination of opioids and psychostimulant drugs, such as amphetamine and methylphenidate. Despite the positive results reported in the literature, this combination is rarely used in clinical practice.