Pain-related Characteristics Research Articles

Risk factors for new episodes of sick leave due to neck or back pain in a working population. A prospective study with an 18-month and a three-year follow-up

Objectives: To identify risk factors for new episodes of sick leave due to neck or back pain. Methods: This prospective study comprised an industrial population of 2187 employees who were...

Chronic Back Pain Is Associated with Decreased Prefrontal and Thalamic Gray Matter Density

The role of the brain in chronic pain conditions remains speculative. We compared brain morphology of 26 chronic back pain (CBP) patients to matched control subjects, using magnetic resonance imaging brain scan data and automated analysis techniques. CBP patients were divided into neuropathic, exhibiting pain because of sciatic nerve damage, and non-neuropathic groups. Pain-related characteristics were correlated to morphometric measures. Neocortical gray matter volume was compared after skull normalization. Patients with CBP showed 5-11% less neocortical gray matter volume than control subjects. The magnitude of this decrease is equivalent to the gray matter volume lost in 10-20 years of normal aging. The decreased volume was related to pain duration, indicating a 1.3 cm3 loss of gray matter for every year of chronic pain. Regional gray matter density in 17 CBP patients was compared with matched controls using voxel-based morphometry and nonparametric statistics. Gray matter density was reduced in bilateral dorsolateral prefrontal cortex and right thalamus and was strongly related to pain characteristics in a pattern distinct for neuropathic and non-neuropathic CBP. Our results imply that CBP is accompanied by brain atrophy and suggest that the pathophysiology of chronic pain includes thalamocortical processes.

Assessing satisfaction with pain medication in primary care patients: Development and psychometric validation of a new measure

Background: The measurement of patient satisfaction with pain medication (SPM) is a potentially useful aid for health care decision-making, but no validated measures for SPM are known.Objective: This study aimed to develop an instrument to assess this patient-reported outcome in primary care and to evaluate whether it satisfactorily fulfilled the required psychometric properties (ie, reliability, validity, and sensitivity to change).Methods: The measure's content was obtained from literature reviews, focus groups, and expert opinion. A preliminary version of 14 self-administered items was obtained and tested in a prospective study in patients receiving pain medication. Item-total statistics and factor analysis were performed to obtain the final version. The final version was psychometrically validated by assessing feasibility, internal consistency (Cronbach's α), convergent validity (multivariant methods), discriminant validity in patients presenting pain relief (receiver operating characteristic curves), test-retest reliability (using the intraclass correlation coefficient [ICC] in patients maintaining medication), and sensitivity to change (in patients changing medication).Results: A total of 1119 patients were recruited (626 women [55.9%]; mean [SD] age, 47.6 [15.36] years; primarily suffering musculoskeletal injury [50.7%]). Four items were deleted from the preliminary version owing to low item-scale correlation and/or factor loadings. The final factor analysis confirmed a 4-factor solution, which explained 81.4% of the variance in questionnaire scores. Adverse events, speed/duration of effect, functional benefit, and overall satisfaction dimensions were identified. Cronbach's α and ICC for the 10-item final version were >0.80 for the summary score and all dimensions. Pain-related characteristics (intensity, frequency, and degree of pain relief), but not patient-related characteristics, were independently associated with the summary score. The area under the curve was 0.78 for the summary score. Effect sizes and standardized response mean were ≥0.84 for the summary score and all dimensions.Conclusion: The SPM questionnaire appears to have good acceptability as well as satisfcctory psychometric properties, based on these analyses.

Differences in pain-related characteristics among younger and older veterans receiving primary care.

To characterize the nature of pain complaints among younger and older veterans receiving primary care, and to determine whether characteristics of pain vary as a function of age. Primary care patients at a Veterans Affairs medical center were screened for pain prior to a routine office visit, and those who endorsed a concern about pain were given a self-administered questionnaire that inquired about specific characteristics of their pain including site, duration, frequency, and average intensity of the pain. Over a 7-month period, 1,290 patients were screened; 641 (50%) reported a concern about pain, and of these, 516 (82%) completed the pain survey. Among younger (age <65 years, N = 191) and older (age > or =65 years, N = 325) respondents, the mean number of sites causing pain was similar (3.6 vs 3.3). Back pain was the most frequently reported site of pain causing the most discomfort among younger (vs older) respondents (31.9% vs 17.8%), whereas older (vs younger) respondents most often endorsed leg pain (32.3% vs 19.9%). The mean duration of pain was not significantly different between older and younger (10.7 vs 10.1 years) respondents; but older (vs younger) respondents were more likely to report constant pain (63.7% vs 46.9%). Using a 0 to 10 numeric rating scale, pain intensity scores were higher among younger (vs older) respondents (5.3 vs 4.3). Rates of prescription pain medication use were not significantly different (52.4% vs 48.0%). Compensation for pain-related disability was more common among younger (vs older) respondents (40.4% vs 19.4%). Concerns about pain are common among veterans receiving primary care. Characteristics of pain, including site, frequency, and intensity, varied as a function of age. Future studies are needed to confirm these findings in other primary care populations and to determine reasons for these differences.

Needs and Problems Related to Occupational Therapy as Perceived by Adult Swedes with Long-Term Pain

The purposes of this study were to describe (1) perceived needs for occupational therapy, (2) the frequency of healthcare visits, (3) specific pain-related characteristics, and (4) to explore differences in these aspects between low ( h 4 visits/year) and high consumers (> 4 visits/year) of healthcare among persons aged 18 -58 years with self-perceived activity limitations/participation restrictions due to long-term/recurrent pain. A sample of 443 individuals with long-term/recurrent pain completed questionnaires concerning these variables. The highest frequencies of perceived needs/problems were reported for ''temporal imbalance'', ''perform activities with greater effort'' and ''tense/stressed due to pain''. Principal component analysis (PCA) yielded four categories of needs/problems: (1) ''limitations in activity performance'', (2) ''need for education'', (3) ''need to regain activities'' and (4) ''adjustment difficulties''. Almost 40% of the respondents had more than four healthcare visits during the previous year. The highest frequencies of specific pain-related characteristics were reported for shoulder/low back pain of searing/aching/gnawing character, and depressive symptoms. The high healthcare consumers (HHC) perceived significantly more interference when performing daily occupations (e.g. stopped/interrupted performance of activity) than did the low healthcare consumers (LHC). The HHC group evidenced higher scores than the LHC group for all PCA-generated factors. The results suggest that persons with long-term/recurrent pain perceive needs/problems related to daily occupations and various depressive symptoms that are particularly frequent among those with high healthcare consumption.

Pain demands attention: A cognitive–affective model of the interruptive function of pain.

Pain interrupts and demands attention. The authors review evidence for how and why this interruption of attention is achieved. The interruptive function of pain depends on the relationship between pain-related characteristics (e.g., the threat value of pain) and the characteristics of the environmental demands (e.g., emotional arousal). A model of the interruptive function of pain is developed that holds that pain is selected for action from within complex affective and motivational environments to urge escape. The implications of this model for research and therapy are outlined with an emphasis on the redefinition of chronic pain as chronic interruption.

473 Cognitive, visual, auditive and pain-related characteristics of the REM dreams

EEG was recorded monopolarly at frontal (F3, F4), central (C3, C4) and posterior (in the middle of O1-P3T5 and O2-P4-T6 triangles) derivations during the hypnotic induction of the Stanford Hypnotic Clinical Scale (SHCS) and during performance following suggestions of hypnotic dream and age-regression as expressed in the before-mentioned scale. 10 low-hypnotizable and 9 highly-hypnotizable and right-handed female students participated in one experimental session. Evaluations were Fast-Fourier spectral analyses during the following conditions: walking-rest in eyes-open and eyes-closed condition; early middle, and late phases of hypnotic induction; rest-hypnosis in eyes closed condition; hypnotic dream and age regression. After spectral analysis of 0 to 44 Hz, the mean spectral amplitude estimates across seven Hz bands (theta1, 4–6 Hz, theta2, 6–8 Hz; alpha1, 8–10 Hz; alpha2, 10–13 Hz; beta1, 13–16 Hz; beta2, 16–20 Hz; beta3, 20–36 Hz) and the 40-Hz EEG band (36–44 Hz) for each experimental condition were extracted. In eyes-open and -closed conditions on walking and hypnosis highly-hypnotizable subjects produced a greater 40-Hz EEG amplitude than did low hypnotizable subjects at all frontal, central and posterior locations. In the early and middle hypnotic induction highly-hypnotizables displayed a greater amount of beta3 than did low hypnotizables and this difference was even more pronounced in the left hemisphere. With posterior scalp recordings, during hypnotic dream and age regression, high hypnotizables displayed, as compared with the rest-hypnosis condition, a decrease in alpha1 and alpha2 amplitudes. This effect was absent for low hypnotizables. Beta1, beta2 abd beta3 amplitudes increased in the left hemisphere during age regression for high hypnotizables; low hypnotizables, in contrast, displayed hemispheric balance across imaginative tasks. High hypnotizables during the hypnotic dream are also displayed in the right hemisphere a greater 40-Hz EEG amplitude as compared with the left hemisphere. This difference was even more evident for posterior recording sites. This hemispheric trend was not evidenced for low hypnotizable subjects. Theta power was never a predictor of hypnotic susceptibility, 40-Hz EEG amplitude displayed a very high main effect (p < 0.004) for hypnotizability in hypnotic conditions by displaying a greater 40 Hz EEG amplitude in high hypnotizables with respect to lows.

Comment on 'Personality Organization as an Aspect of Back Pain in a Medical Setting.'

The methodology and results of a recent investigation by Louks, Freeman, and Calsyn (1978) are reviewed. It is demonstrated that the results may have been confounded by inappropriate experimental procedures. Regardless of the methodological deficiencies associated with the experimental procedures, the results do not provide adequate support for the continued differentiation of individual low back pain patients with respect to the etiology of their pain. It is suggested that psychologists may best contribute to the assessment and treatment of individual pain patients by developing actuarial rules regarding the pain-related behavioral characteristics shared by members of various patient subgroups and the specific treatments to which subgroup members best respond.