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A prospective study of opioid induced hyperalgesia in healthy volunteers
Abstracts (156) Coping behaviors in ethnically diverse cancer survivors A Mac, T Hart-Johnson, and C Green; University of Michigan, Ann Arbor, MI Cancer-related chronic pain is common amongst cancer survivors. Psychological factors, such as coping, influence both cancer and the pain experience. The cancer pain literature supports the importance of coping, although the relationship between specific coping methods and pain is not entirely clear (especially in ethnically diverse cancer survivors). This cross-sectional study randomly sampled black and white cancer survivors (N= 152, 23% blacks, 77% whites) from the Michigan State Cancer Registry. After agreeing to participate, subjects were mailed a questionnaire focusing on their socio-demographic characteristics, overall health, cancer and treatment history, and pain experience. A revised version of The Coping Strategies Questionnaire (CSQ-R), shortened to 23 items to reduce response burden, was employed to describe the relationship between specific coping mechanisms and socio-demographic characteristics (gender, race) in cancer survivors with current (19%) and without current pain, and those with (45%) and without pain since diagnosis. CSQ-R was tested for scale reliability. Scales (and where necessary, individual items) were tested in regressions which included demographics, pain status, coping and interactions between coping and sex, race, and pain status predicting depression, general health, physical functioning and emotional functioning. Distracting, ignoring and reinterpreting pain are largely unrelated to outcomes, but those items falling under the heading catastrophizing (4 distinct statements that did not scale) have several significant relationships, directly or via interaction, with outcomes. Most interactions were with pain status, although female catastrophizing is related to poorer physical functioning irrespective of whether the subject is in pain. These data suggest efforts should be made to identify interventions that reduce catastrophizing in those with cancer-related pain. These preliminary findings suggest coping strategies (e.g., cognitive behavioral techniques) targeted specifically at diminishing catastrophizing may lead to improved pain management in the chronic cancer pain setting.
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B04 Central Pain (158) A prospective study of opioid induced hyperalgesia in healthy volunteers D Tompkins, M Smith, G Bigelow, and E Strain; Johns Hopkins University, Baltimore, MD Opioid medications are standard treatments for moderate to severe pain. However, prolonged use may result in an increased sensitivity to painful stimuli – a phenomenon termed opioid induced hyperalgesia (OIH). In humans, the development of OIH is not well characterized. This double blind group comparison study evaluated the effects of twice weekly intramuscular (IM) doses of alfentanil (ALF) or a control condition (diphenhydramine, DPH) on the time course of OIH development. The study was limited to healthy males given potential menstrual cycle effects on OIH. Eight sessions (twice per week for four weeks) lasted 8 hours each, and consisted of cold pressor, algometer, and innocuous stimulation tasks assessed at baseline, 30, 90, 180, 270, 360, and 480 minutes after IM injection. Drug effects were measured through subject- and observer-reported questionnaires as well as vital signs and pupillometry collected at the same time points. Plasma and 24-hour urine samples were drawn to examine the effect of alfentanil metabolism on OIH development. Primary outcome measurements were changes in cold pressor threshold and tolerance between drug conditions. Other analyses included changes in pressure pain threshold and tolerance; correlations between pain measurements and alfentanil/noralfentanil plasma concentrations; means and time course of drug effect measurements; racial differences in pain testing; and personality differences as measured by the NEO-Personality Inventory. Though the complete study will report an N of 12, preliminary results from 6 completers showed downward trends in mean cold pressor tolerance values to suggest the development of OIH over time. Interestingly, cold pressor threshold values showed an opposite trend. Pupil miosis time course demonstrated acute alfentanil effects that dissipated and returned to normal over the 8-hour session. This model holds promise for observing and experimentally studying OIH in the human laboratory. (Supported by NIH grants K24 DA023186 and T32 DA07209.)
(157) Quality improvement for symptom control in underserved Chinese American cancer patients
(159) Central and peripheral hypersensitivity in the irritable bowel syndrome
L Dhingra, K Lam, P Homel, G Lo, J Chen, S Chan, W Lam, V Chang, and R Portenoy; Beth Israel Medical Center, New York, NY
Q Zhou, R Fillingim, J Riley, W Malarkey, and G Verne; Ohio State University, Columbus, OH
Chinese Americans, the largest Asian subgroup in the US, have a high rate of cancer. Patients commonly present with advanced illness and have an elevated risk for poorly controlled pain. Quality improvement (QI) methodologies, such as rapid-cycle QI, have been shown to improve pain control clinical practice and patient-reported outcomes. However, there is a lack of research testing culturally tailored pain management QI programs among Chinese Americans. In this ongoing community study, we are developing and testing a rapid-cycle QI model to improve pain management and outcomes among underserved, Chinese American cancer patients. The aims of the study are: (1) to test the effectiveness of a rapid-cycle QI intervention to enhance the processes and outcomes of pain management for poor and underserved ethnic Chinese cancer patients; (2) to determine whether a rapid-cycle QI intervention for pain can be generalized to other symptoms (fatigue and dyspnea); and (3) to identify demographic, cultural, psychological, and family-related barriers and facilitators that are related to the uptake of the intervention. Ethnic Chinese cancer patients and clinicians from two large community oncology practices are the targets of the intervention. This systems-based intervention, which is incorporated into repeated ‘‘plan-do-study-assess’’ QI cycles in collaboration with the oncology practices, includes: pain screening, strategies for follow-up and early treatment, referral, and clinician education. The effectiveness of the intervention is determined by longitudinal data collection in cohorts of 50 patients (assessed at pre-intervention and every 4 months after implementation begins). The primary outcome is the change over time in the proportion of cancer patients who achieve adequate and timely pain control. Findings will highlight the importance of interventions to reduce pain disparities among underserved Chinese Americans, and the relevance of community-based QI programs for producing long-term changes in clinical pain management.
Previous investigations of somatic hypersensitivity in IBS patients have typically involved only a single stimulus modality, and little information exists regarding whether patterns of somatic pain perception vary across stimulus modalities within a group of patients with IBS. Therefore, the current study was designed to characterize differences in perceptual responses to a battery of noxious somatic stimuli in IBS patients compared to controls. A total of 78 diarrhea-predominant and 57 controls participated in the study. We evaluated pain threshold and tolerance and sensory and affective ratings of contact thermal, mechanical pressure, ischemic stimuli, and cold presser stimuli. In addition to assessing perceptual responses, we also evaluated differences in neuroendocrine and cardiovascular responses to these experimental somatic pain stimuli. A subset of IBS patients demonstrated the presence of somatic hypersensitivity to thermal, ischemic, and cold pressor nociceptive stimuli. The somatic hypersensitivity in IBS patients was somatotopically organized in that the lower extremities that share viscerosomatic convergence with the colon demonstrate the greatest hypersensitivity. There were also significant changes in ACTH, cortisol, and systolic blood pressure in response to the ischemic pain testing in IBS patients when compared to controls. The results of this study suggest that a more widespread alteration in central pain processing in a subset of IBS patients may be present as they display hypersensitivity to heat, ischemic, and cold pressor stimuli.
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B04 Central Pain (158) A prospective study of opioid induced hyperalgesia in healthy volunteers D Tompkins, M Smith, G Bigelow, and E Strain; Johns Hopkins University, Baltimore, MD Opioid medications are standard treatments for moderate to severe pain. However, prolonged use may result in an increased sensitivity to painful stimuli – a phenomenon termed opioid induced hyperalgesia (OIH). In humans, the development of OIH is not well characterized. This double blind group comparison study evaluated the effects of twice weekly intramuscular (IM) doses of alfentanil (ALF) or a control condition (diphenhydramine, DPH) on the time course of OIH development. The study was limited to healthy males given potential menstrual cycle effects on OIH. Eight sessions (twice per week for four weeks) lasted 8 hours each, and consisted of cold pressor, algometer, and innocuous stimulation tasks assessed at baseline, 30, 90, 180, 270, 360, and 480 minutes after IM injection. Drug effects were measured through subject- and observer-reported questionnaires as well as vital signs and pupillometry collected at the same time points. Plasma and 24-hour urine samples were drawn to examine the effect of alfentanil metabolism on OIH development. Primary outcome measurements were changes in cold pressor threshold and tolerance between drug conditions. Other analyses included changes in pressure pain threshold and tolerance; correlations between pain measurements and alfentanil/noralfentanil plasma concentrations; means and time course of drug effect measurements; racial differences in pain testing; and personality differences as measured by the NEO-Personality Inventory. Though the complete study will report an N of 12, preliminary results from 6 completers showed downward trends in mean cold pressor tolerance values to suggest the development of OIH over time. Interestingly, cold pressor threshold values showed an opposite trend. Pupil miosis time course demonstrated acute alfentanil effects that dissipated and returned to normal over the 8-hour session. This model holds promise for observing and experimentally studying OIH in the human laboratory. (Supported by NIH grants K24 DA023186 and T32 DA07209.)
(157) Quality improvement for symptom control in underserved Chinese American cancer patients
(159) Central and peripheral hypersensitivity in the irritable bowel syndrome
L Dhingra, K Lam, P Homel, G Lo, J Chen, S Chan, W Lam, V Chang, and R Portenoy; Beth Israel Medical Center, New York, NY
Q Zhou, R Fillingim, J Riley, W Malarkey, and G Verne; Ohio State University, Columbus, OH
Chinese Americans, the largest Asian subgroup in the US, have a high rate of cancer. Patients commonly present with advanced illness and have an elevated risk for poorly controlled pain. Quality improvement (QI) methodologies, such as rapid-cycle QI, have been shown to improve pain control clinical practice and patient-reported outcomes. However, there is a lack of research testing culturally tailored pain management QI programs among Chinese Americans. In this ongoing community study, we are developing and testing a rapid-cycle QI model to improve pain management and outcomes among underserved, Chinese American cancer patients. The aims of the study are: (1) to test the effectiveness of a rapid-cycle QI intervention to enhance the processes and outcomes of pain management for poor and underserved ethnic Chinese cancer patients; (2) to determine whether a rapid-cycle QI intervention for pain can be generalized to other symptoms (fatigue and dyspnea); and (3) to identify demographic, cultural, psychological, and family-related barriers and facilitators that are related to the uptake of the intervention. Ethnic Chinese cancer patients and clinicians from two large community oncology practices are the targets of the intervention. This systems-based intervention, which is incorporated into repeated ‘‘plan-do-study-assess’’ QI cycles in collaboration with the oncology practices, includes: pain screening, strategies for follow-up and early treatment, referral, and clinician education. The effectiveness of the intervention is determined by longitudinal data collection in cohorts of 50 patients (assessed at pre-intervention and every 4 months after implementation begins). The primary outcome is the change over time in the proportion of cancer patients who achieve adequate and timely pain control. Findings will highlight the importance of interventions to reduce pain disparities among underserved Chinese Americans, and the relevance of community-based QI programs for producing long-term changes in clinical pain management.
Previous investigations of somatic hypersensitivity in IBS patients have typically involved only a single stimulus modality, and little information exists regarding whether patterns of somatic pain perception vary across stimulus modalities within a group of patients with IBS. Therefore, the current study was designed to characterize differences in perceptual responses to a battery of noxious somatic stimuli in IBS patients compared to controls. A total of 78 diarrhea-predominant and 57 controls participated in the study. We evaluated pain threshold and tolerance and sensory and affective ratings of contact thermal, mechanical pressure, ischemic stimuli, and cold presser stimuli. In addition to assessing perceptual responses, we also evaluated differences in neuroendocrine and cardiovascular responses to these experimental somatic pain stimuli. A subset of IBS patients demonstrated the presence of somatic hypersensitivity to thermal, ischemic, and cold pressor nociceptive stimuli. The somatic hypersensitivity in IBS patients was somatotopically organized in that the lower extremities that share viscerosomatic convergence with the colon demonstrate the greatest hypersensitivity. There were also significant changes in ACTH, cortisol, and systolic blood pressure in response to the ischemic pain testing in IBS patients when compared to controls. The results of this study suggest that a more widespread alteration in central pain processing in a subset of IBS patients may be present as they display hypersensitivity to heat, ischemic, and cold pressor stimuli.