Biomedical subjects

M E Robinson

Publications and source records attributed to M E Robinson.

At least 19 recordsLinked to original sources

PubMed2006

Overall fibromyalgia pain is predicted by ratings of local pain and pain-related negative affect--possible role of peripheral tissues.

OBJECTIVES: Despite variable numbers and intensities of local pain areas, fibromyalgia (FM) patients can provide overall clinical pain ratings. We hypothesized that the overall clinical pain is largely determined by the pain intensity of local body areas. Thus, we assessed the role of local body pains as predictors of overall clinical pain in FM patients. METHODS: Ratings of overall clinical pain intensity and pain-related negative affect (PRNA) were obtained from 277 FM patients. In addition, the patients identified painful body areas by shading a body pain diagram and rated the intensity of each pain area using a mechanical visual analogue scale (VAS). Hierarchical regression analyses were used to examine predictors of overall clinical FM pain intensity including PRNA, number of local pain areas, and maximal/average intensity of local pain areas. RESULTS: The average overall clinical pain rating of all FM patients was 4.6 (S.D. 2.3) VAS. The PRNA accounted for 19%, number of painful body areas for 9% and maximal/average local pain for 27% of the variance of overall clinical FM pain (P-values < 0.001). The combination of all factors predicted 55% of the variance in overall clinical pain intensity of FM patients. CONCLUSION: Peripheral factors (maximal/average local pain and number of painful body areas) predicted most of the variance of overall clinical FM pain, suggesting that the input of pain by the peripheral tissues is clinically relevant. About 19% of the pain variance was predicted by PRNA. Thus, peripheral pain and negative affect appear to be particularly relevant for overall FM pain and may represent important targets for future therapies.

Adult↗

PubMed2003

Sex differences in delayed onset muscle soreness.

AIM: There is agreement that females report greater pain in response to typical experimental pain stimuli than males. However, investigations of sex differences in the sensation of delayed onset muscle soreness (DOMS) have equivocal RESULTS: The objective of this investigation was to examine sex differences in the pain from DOMS with an adequate sample size, quantification of stimulus intensity, and 2 measures of pain. METHODS: Sixty-seven participants (52% females) completed a 2-session protocol. DOMS was induced using eccentric resistance exercises in the elbow flexors of the non-dominant arm. The intensity of the eccentric contractions was based upon concentric strength. Pain response was measured 48 hrs later. The dependent variables were pressure threshold, which was assessed using a dolorimeter, and pain intensity when the arm was moved through full active range of motion, which was assessed with a visual analog scale. RESULTS: The occurrence of DOMS was confirmed by a decrease in pressure threshold after the eccentric contractions and higher pain intensity in the arm that performed the eccentric contractions than the arm that did not. Females reported lower pain intensities (M=3.41, SD=2.13) compared to males (M=5.12, SD=2.05), but no significant sex difference was found in pressure threshold. CONCLUSION: In this investigation, females reported lower muscle pain intensity than males, but showed no sex difference in pressure threshold. These and previous findings suggest that the detection of a sex difference in muscle pain depends upon the methodology of inducing DOMS and measuring sensation.

Adult↗

PubMed2002

The influence of endurance exercise on delayed onset muscle soreness.

BACKGROUND: Despite several review articles supporting the existence of exercise induced analgesia, it is unclear whether exercise reduces delayed onset muscle soreness (DOMS). The purpose of this investigation was to examine the influence of an acute bout of endurance exercise on delayed onset muscle pain. METHODS: DOMS was induced in the elbow flexors of the non-dominant arm using eccentric isotonic exercise with the intensity of the eccentric contractions based upon concentric strength. Forty-eight hours after the eccentric contractions participants were randomly assigned to a group that completed 20 min of endurance exercise at 80% of estimated maximum cardiorespiratory endurance (n=23) or a group that watched a 20 min emotionally neutral video (n=27). The dependent variables were pressure pain threshold, pain intensity during arm movement through active range of motion, a standardized pain rating that was determined from a magnitude matching procedure, and state anxiety. RESULTS: A significant decrease in pressure pain threshold and an increase in the standardized pain ratings after the DOMS procedure (p<0.05) indicated that muscle pain was successfully induced. These changes were components of significant quadratic trends for pressure threshold (p<0.05) and the standardized pain ratings (p<0.01). During the 2nd session a decrease in pain intensity approached significance (p=0.05) regardless of group assignment. However, no significant group by time interactions were detected for any of the pain measures or state anxiety. CONCLUSIONS: Cycle ergometer exercise was not found to alter delayed onset muscle pain.

Adult↗

PubMed2002

MMPI-2 profiles of patients with intractable epilepsy.

MMPI-2 profiles of 93 presurgical intractable epilepsy patients were examined using Ward's method of cluster analysis. Three clusters were identified. The means of each cluster suggest that 45% of the sample had minimal psychological complaints, 30% presented with generalized clinical elevations, and 25% of the patients had profiles of intermediate elevations with a tendency to emphasize somatic complaints and/or depression. Gender, age of seizure onset, and seizure laterality were not found to be uniquely associated with the cluster profiles. Further examination of correlates of group membership is warranted to provide information for treatment planning.

Journal Article↗

PubMed2001

Gender role expectations of pain: relationship to sex differences in pain.

Empirical research supports the existence of sex differences in pain; yet these differences are poorly understood. Although biological mechanisms have been posited to explain variability, results of pain modeling manipulations suggest social learning may be a stronger influence on pain response. In this report we use the term sex to refer to the biological category of male or female. We use the term gender to refer to the socially acquired aspects of being male or female sometimes referred to as femininity and masculinity. This study investigated a new measure, the Gender Role Expectations of Pain questionnaire (GREP), which was designed to measure sex-related stereotypic attributions of pain sensitivity, endurance, and willingness to report pain. Subjects were 156 male and 235 female undergraduates at a southeastern university. Psychometric investigation of the questionnaire revealed a 5-factor solution that closely mirrored the theoretical construction of the items. Test-retest reliability was also shown for individual items on a separate sample of 28 subjects. Results supported hypotheses about gender role: both men and women rated men as less willing to report pain than women (F(1,389) = 336, P <.001); both men and women rated women more sensitive (F(1,389) = 9.5, P <.05) and less enduring of pain (F(1,389) = 65.7, P <.001) than men; and men rated their own endurance as higher than the typical man (F(1,389) = 65.7, P <.001). Sex accounted for 46% of the variance in willingness to report pain. Results suggest that the GREP distinguished between the socially learned reactions to pain for men and women. It is recommended that the influence of gender-related expectations for pain be assessed in all studies investigating human sex differences in pain.

Journal Article↗

PubMed2001

Perceived spouse responsiveness to chronic pain: three empirical subgroups.

The spouse plays a fundamental role in day-to-day functioning and long-term well-being of the patient with chronic pain. Although spouses may respond differently to pain demonstrations, no study has examined patterns of perceived spouse responsiveness to chronic pain behavior. Yet perceived patterns of response to chronic pain may explain variability in pain behavior in the literature because studied samples may be drawn from any one subgroup. The purposes of this study were to run an exploratory cluster analysis to identify naturally occurring spouse response subgroups by using section 2 of the Multidimensional Pain Inventory and to examine pain-relevant variables between subgroups. It was hypothesized that subgroups would be identified and that they would differ on pain-relevant variables. Participants were 774 married pain patients from 2 University of Florida-affiliated pain clinics, 69% of whom experienced chronic low back pain. A hierarchical cluster analysis identified 3 subgroups that were labeled positively attentive, negatively attentive, and inattentive. A discriminant analysis yielded 2 significant discriminant functions that correctly classified 71.1% of subgroup membership. The support variable best differentiated between the positively and negatively attentive subgroups, whereas interference best distinguished between the negatively attentive and inattentive subgroups. Results suggest the profiles have conceptual and clinical validity, with the negatively and positively attentive subgroups exhibiting the poorest adjustment to pain. A controlled study is needed to determine the direction of causality.

Journal Article↗

PubMed2001

Sex differences in negative emotional responses to chronic pain.

We proposed a sequential model of pain processing with pain intensity as stage 1, pain unpleasantness as stage 2, pain-related emotions (depression, anxiety, frustration, anger, fear) as stage 3, and overt behavioral expression of pain as stage 4. We tested hypotheses about relationships between sex and the first 3 stages of pain processing by conducting simultaneous regression analysis using LISREL-8 with data collected from 967 women and 680 men with chronic pain. We found the following results: (1) women reported higher pain-related frustration and fear; (2) frustration related most highly to pain intensity among women, as compared with anxiety and depression among men; (3) depression and frustration related most highly to usual and highest pain unpleasantness among women, as compared with frustration among men; and (4) contrary to expectations, pain-related emotions were more strongly related to pain for men. Consistent with the sequential model of pain processing, emotional response to pain was more closely related to pain unpleasantness than to pain intensity across sex. Anxiety and frustration were the emotions most highly related to pain. The current results highlight sex differences in the experience of chronic pain and the importance of assessing a range of emotions in patients with pain.

Journal Article↗

PubMed2001

Sleep disturbance in orofacial pain patients: pain-related or emotional distress?

Associations between pain, depression, and sleep disturbance have been documented in several chronic pain patient samples. The current study assessed the prevalence and magnitude of sleep disturbance in a sample of 128 orofacial pain patients referred for clinical evaluation and tested linkages between sleep, depression, anxiety, and pain using cross-sectional and longitudinal data. Seventy-seven percent of the patients reported reduced sleep quantity since pain onset. In cross-sectional analyses, reduced sleep quantity was associated with depression and pain. Reduced sleep quality was associated with negative affect. Longitudinally, initial depression and pain predicted sleep at time two and initial pain predicted negative affect. Sleep did not predict pain. Results support the hypothesis that pain, rather than sleep disturbance, increases negative affect across time, whereas negative affect is more a cause of concurrent reduced sleep quality than is pain. The results highlight the importance of assessing for sleep disturbance in orofacial pain patients.

Adolescent↗

PubMed2001

Facilitation of quadriceps activation following a concentrically controlled knee flexion movement: the influence of transition rate.

STUDY DESIGN: Single group repeated measures design. OBJECTIVE: To determine if the rate of transition between knee flexion and extension influences the subsequent concentric activation of the quadriceps and knee extension torque during reciprocal movements. BACKGROUND: Preloading a muscle by stretching, a prior isometric or eccentric muscle action, or a prior movement controlled concentrically by the antagonist muscle group increases the maximal torque-generating capability of the agonist. We hypothesized that the rate of transition from the prior movement may be the critical factor that influences the degree of muscle facilitation and torque potentiation. Rapid reversal of antagonistic movements has been postulated as a potential facilitatory mechanism. METHODS: Knee extension torque and electromyographic (EMG) amplitude (dependent variables) from 2 of the vasti muscles were recorded while subjects (N = 20; 12 men, 8 women, mean age, 28.5+/-2.68 years) maximally activated their quadriceps at 3 constant angular velocities, 100 degrees/s, 200 degrees/s, and 300 degrees/s, and 2 preload conditions, SLOW and RAPID (independent variables). In the SLOW transition condition, subjects actively flexed their knee to 110 degrees from an extended position, paused in this position for 3 seconds, and then extended to 0 degrees. In the RAPID transition condition, the same movement from knee flexion to extension was performed without a pause. RESULTS: Peak torque, the root-mean-square (RMS) average, peak (peak rectified and smoothed), and initial (100 milliseconds prior to torque onset) EMG amplitudes were all significantly greater during the RAPID transition condition. Peak torque decreased with increasing movement velocity. There were no interactions between the preload conditions and angular velocity on peak torque or the EMG amplitude variables. There was also no influence of velocity on the EMG amplitude variables. CONCLUSIONS: The effect of preloading the quadriceps by prior concentric activation of the hamstrings is dependent on the rate of transition between the flexion and extension movements and is due primarily to neural facilitation.

Adult↗

PubMed2001

Nutritional assessment of a predominately African-American inner-city clinic population.

BACKGROUND: Dietary changes are recommended as first-line treatment and prevention strategies of chronic diseases. The African-American diet in particular has been characterized as high in sodium and fat while lacking in fiber. METHODS: Using a 24-hour diet recall with a modified food frequency questionnaire (FFQ), we assessed the diet/nutritional status of patients attending 2 inner-city health centers in Milwaukee. Point-of-purchase data on food sales was collected for comparison. RESULTS: Diets were high in fat (42.7% of total calories), saturated fat (14.6%), and sodium (nearly 150% of the daily recommended value), while lacking in dietary fiber (30% of the daily recommended value). Point-of-purchase data correlated with dietary intake. CONCLUSIONS: The diets of the population surrounding these inner-city health centers were high in fat and sodium, but low in fiber. Programs are needed to address the unhealthy dietary practices within this population.

Adult↗

PubMed2001

Factors predicting orofacial pain patient satisfaction with improvement.

AIMS: To determine psychosocial predictors of patients' ratings of satisfaction with improvement and subjective pain relief. This study also examined the underlying components of patient satisfaction with improvement, as assessed at follow-up. METHODS: The sample consisted of 107 chronic orofacial pain patients evaluated at a university-based orofacial pain clinic and referred for treatment with individualized treatment plans. Pain and psychosocial functioning were assessed with standard, reliable, validated self-report instruments administered at the initial evaluation. Follow-up data were collected via a telephone-administered structured interview 8 months after the initial evaluation. Regression methodology was used to determine prediction models for satisfaction with improvement and subjective pain relief. Patient ratings of the quality of the caregiver communication were used as a control variable in all analyses. RESULTS: Quality of caregiver communication predicted approximately 10 to 14% of the variance in outcomes in all models. Greater initial use of cognitive coping strategies and reduced depression predicted higher ratings of satisfaction with improvement and increased pain relief. When concurrent relationships among variables at the follow-up were examined, greater subjective pain relief since the evaluation, lower current pain, and higher ratings of overall mood were significant predictors of patient satisfaction with improvement. CONCLUSION: This study is one of the first to report that the use of certain cognitive coping strategies is associated with positive outcome for patients suffering from orofacial pain. These findings underscore the importance of individual differences on behavioral and psychosocial parameters in the prediction of patients' subjective evaluation of treatment outcome.

Activities of Daily Living↗

PubMed2000

Implications of EPHB6, EFNB2, and EFNB3 expressions in human neuroblastoma.

Neuroblastoma (NB) is a common pediatric tumor that exhibits a wide range of biological and clinical heterogeneity. EPH (erythropoietin-producing hepatoma amplified sequence) family receptor tyrosine kinases and ligand ephrins play pivotal roles in neural and cardiovascular development. High-level expression of transcripts encoding EPHB6 receptors (EPHB6) and its ligands ephrin-B2 and ephrin-B3 (EFNB2, EFNB3) is associated with low-stage NB (stages 1, 2, and 4S) and high TrkA expression. In this study, we showed that EFNB2 and TrkA expressions were associated with both tumor stage and age, whereas EPHB6 and EFNB3 expressions were solely associated with tumor stage, suggesting that these genes were expressed in distinct subsets of NB. Kaplan-Meier and Cox regression analyses revealed that high-level expression of EPHB6, EFNB2, and EFNB3 predicted favorable NB outcome (P<0.005), and their expression combined with TrkA expression predicted the disease outcome more accurately than each variable alone (P<0.00005). Interestingly, if any one of the four genes (EPHB6, EFNB2, EFNB3, or TrkA) was expressed at high levels in NB, the patient survival was excellent (>90%). To address whether a good disease outcome of NB was a consequence of high-level expression of a "favorable NB gene," we examined the effect of EPHB6 on NB cell lines. Transfection of EPHB6 cDNA into IMR5 and SY5Y expressing little endogenous EPHB6 resulted in inhibition of their clonogenicity in culture. Furthermore, transfection of EPHB6 suppressed the tumorigenicity of SY5Y in a mouse xenograft model, demonstrating that high-level expressions of favorable NB genes, such as EPHB6, can in fact suppress malignant phenotype of unfavorable NB.

Animals↗

PubMed2000

Prognostic significance of EPHB6, EFNB2, and EFNB3 expressions in neuroblastoma.

BACKGROUND: EPH family receptor tyrosine kinases and their ligand ephrins play pivotal roles in development. High-level expression of transcripts encoding EPHB6 receptors (EPHB6), its ligands ephrin-B2 and ephrin-B3 (EFNB2, EFNB3) is predictive of favorable disease outcome of neuroblastoma (NB). When combined with TrkA expression, the expression of EPHB6, EFNB2, or EFNB3 predicts more accurately the disease outcome than each of the four variables alone. PROCEDURE: Cox regression and Kaplan-Meier analyses were used to assess the prognostic significance of EPHB6, EFNB2, EFNB3, and TrkA expressions in NB without MYCN amplification. RESULTS: High-level expression of EFNB3 or TrkA predicted favorable NB outcome of NB without MYCN amplification (p < 0.03). As found in the general NB population, EPHB6, EFNB2, or EFNB3 expression in combination with TrkA expression was significantly predictive of the disease outcome of normal MYCN NB (p < 0.01). CONCLUSIONS: EPHB6, EFNB2, and EFNB3 expressions may permit further refinement of the prognostic stratification of NB into favorable and unfavorable groups.

Child↗

PubMed2000

Bayesian methods for a growth-curve degradation model with repeated measures.

The increasing reliability of some manufactured products has led to fewer observed failures in reliability testing. Thus, useful inference on the distribution of failure times is often not possible using traditional survival analysis methods. Partly as a result of this difficulty, there has been increasing interest in inference from degradation measurements made on products prior to failure. In the degradation literature inference is commonly based on large-sample theory and, if the degradation path model is nonlinear, their implementation can be complicated by the need for approximations. In this paper we review existing methods and then describe a fully Bayesian approach which allows approximation-free inference. We focus on predicting the failure time distribution of both future units and those that are currently under test. The methods are illustrated using fatigue crack growth data.

Bayes Theorem↗

PubMed2000

Better palpation of pain: reliability and validity of a new pressure pain protocol in TMD.

The purpose of this research was to employ a double-blind placebo control design of iontophoretically administered lidocaine to assess the test-retest reliability and validity of a magnitude matching procedure using a pressure algometer. In studies in the literature on assessment of pain in temporomandibular disorders (TMD), the pressure algometer has been found to be a reliable means of measuring pressure-pain threshold and a sensitive measure of treatment-response in the laboratory. However, previous research with this apparatus has not employed more sophisticated psychophysics. This study employs a magnitude matching psychophysical protocol to obtain a multidimensional pain report. Test-retest reliability over two occasions, 3-8 days apart, was found to be moderate for discriminability (r = .71, p < .01) but poor for response bias (r = .44). The validity study used iontophoresis as an anesthetic in a double-blind placebo and no-treatment control design. Although it was hypothesized that subjects in the anesthesia group would demonstrate reduced discriminability as compared with the control groups, no differences were found among the three groups on this measure. However, differences in response bias were found, with both the placebo control and no-treatment control groups differing from the experimental group but not from each other. Possible explanations and the implications of these findings are discussed.

Adult↗

PubMed2000

Negative affect, self-report of depressive symptoms, and clinical depression: relation to the experience of chronic pain.

OBJECTIVE: The goal of this study was to examine the relative importance of global affective distress, self-report of depressive symptoms, and presence or absence of major depression to the experience of chronic pain. SETTING: A multidisciplinary pain program at a university medical center was the setting for this study. PATIENTS: Subjects in this study were 211 consecutive patients with chronic pain. OUTCOME MEASURES: Pain duration, compensation, and litigation status were controlled for in the statistical analyses, as each correlated significantly with at least one of the measures of affect. Global affective distress was assessed using the Global Severity Index (GSI) from the Brief Symptom Inventory. The Beck Depression Inventory and the Center for Epidemiological Studies Depression Scale were used as measures of self-report of depressive symptoms. Presence or absence of major depression was based on DSM-IV criteria. RESULTS AND CONCLUSIONS: The GSI, Beck Depression Inventory, and Center for Epidemiological Studies Depression Scale were significantly correlated with each measure of the experience of pain, although clinical depression was only significantly related to self-reported disability and negative thoughts about pain. The self-report measures of depression maintained their relation to the dependent measures when the somatic items from the scales were removed, suggesting that the relations were not spuriously due to the influence of pain symptoms on the scales. When examining the unique contribution of each variable to the experience of pain (by simultaneously controlling for the other measures of affect), the GSI was uniquely related to the sensory and affective components of pain. Self-report of depressive symptoms was more highly related to a measure of the evaluative component of pain and uniquely related to self-reported disability and negative thoughts about pain. The results are discussed within the context of theoretical models of the relation between pain and affect, and suggestions for future research are presented.

Adult↗

PubMed2000

Clinical pain perception and hormone replacement therapy in postmenopausal women experiencing orofacial pain.

OBJECTIVE: The purpose of this study was to examine the magnitude of the relation between a postmenopausal woman's hormonal replacement status and clinical pain report in a sample of women experiencing orofacial pain. DESIGN: To accomplish this, pain ratings were collected during a routine chronic pain evaluation at an orofacial pain clinic from a sample of 87 postmenopausal women. RESULTS: Results of ANCOVA (controlling for pain duration) demonstrated that postmenopausal women receiving hormone replacement therapy (HRT) reported higher levels of pain than postmenopausal women not taking HRT. Numeric pain rating scales revealed large effect sizes for worst pain report (0.62), moderate differences for average (0.48) and current (0.39) pain levels, and trivial differences for least pain (0.04). Effect sizes for the McGill Pain Questionnaire indicated somewhat smaller differences (0.35-0.24) between the two groups. CONCLUSIONS: This study is among the first to examine the relation between a woman's hormonal status and clinical pain perception and is the first to investigate the role of HRT in a postmenopausal woman's orofacial pain report in a clinical treatment setting. This area of inquiry is particularly salient given the high percentage of women who choose to initiate HRT either after hysterectomy or with the onset of menopause.

Adult↗

PubMed2000

Somatic, affective, and pain characteristics of chronic TMD patients with sexual versus physical abuse histories.

AIMS: This study examined whether temporomandibular disorder (TMD) patients with sexual versus physical abuse histories differ in their pain report, psychological distress, and somatic symptoms. METHODS: Participants were 114 female TMD patients. The sample was divided into 3 groups based on abuse history: sexual abuse, physical abuse, or no abuse. Abuse histories were assessed with a structured clinical interview. Measures used included the McGill Pain Questionnaire, the State-Trait Anxiety Inventory, the Beck Depression Inventory, and the Pennebaker Inventory of Limbic Languidness. Group differences were analyzed by analysis of variance and Bonferroni post hoc comparisons. RESULTS: Temporomandibular disorder patients with a history of physical abuse reported significantly more pain, anxiety, and depressive symptoms than did patients with a history of sexual abuse or no history of abuse. Furthermore, the results suggest that TMD patients with a sexual abuse history are not significantly different from patients with no abuse history across the domains studied. CONCLUSION: Based on the differences found, it can be argued that assessment of physical abuse histories by appropriately trained clinicians should be a routine part of any multimodal assessment of female chronic TMD patients.

Adolescent↗