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(931)
Abstracts
S83
(931) Refer to Oral Paper Session 306
(934) Refer to Oral Paper Session 336
G04 - Clinical Outcomes Measurement
(935) Cognitive assessment in the fibromyalgia syndrome (FMS) using the Trail Making Test-B (TMTB)
(932) Reliability and validity of pain interference measures for persons with SCI
W Haynes, I Russell, J Michalek; The University Clinical Research Center, San Antonio, TX This study determined whether the TMTB would identify a cognitive defect among FMS patients compared with healthy normal controls (HNC). Primary FMS patients [1990 ACR criteria] and HNC were each studied between 8:00 am and noon on a single visit. Each subject was given three simple practice TMTs followed by the timed TMTB. The primary outcome variable was the time required to complete the exercise. Also documented were the numbers of errors and the product (time x errors). A by-group analysis of variance, adjusted for demographic variables, contrasted the mean scores for pain, anxiety, depression, function, stiffness and fatigue. A total of 151 subjects were enrolled (FMS N⫽90; HNC N⫽61]). Of the FMS, 84 were female, average age 50.6 years, and 72% Caucasian. The FMS were older (50.6 versus 44.7 years, p⫽0.009) than the HNC, had higher pain visual analog scale (38.6, vs. 2.9 mm), and more severe insomnia (7.3 cm versus 2.0 cm). For all subjects, FMS group took longer to complete the test (60.1 vs. 45 seconds, p⬍0.001) and made more errors than HNC (3.3 vs. 1.3, p⫽0.012), products (209.3 vs. 63.9, p⫽0.004). FMS not taking FMS medications (N⫽48) differed from HNC in time (60.5 vs. 45.1 seconds, p⫽0.008) but not in errors. FMS still taking FMS medications (N⫽42) took longer (60.0 vs. 45.3, p⬍0.001) and made more errors (3.6 vs.1.4, p⫽0.007), product (229.2 vs. 68.7, p⫽0.003). A matched analysis with 22 one-to-one demographically matched pairs produced similarly significant results. None of the clinical measures in either group correlated with the TMTB scores. These findings demonstrated that the TMTB was capable of detecting cognitive dysfunction in FMS. Use of FMS medications compounded this defect. Attempts to correlate these findings with clinical variables failed to disclose a logical model.
K Raichle, T Osborne, M Jensen; University of Washington School of Medicine, Seattle, WA There is a need to identify factors that are related to pain in persons with SCI that might be amenable to pain management interventions. Identification of such factors requires the use of psychometrically sound measures to assess important treatment outcome domains, such as pain interference. The current study examined the content validity and internal reliability of the Brief Pain Inventory (BPI) Interference scale, including the 7-item version, and modified 10- and 12-item versions, and the Graded Chronic Pain (GCP) Disability scale in a sample of persons with SCI and chronic pain. 157 participants with SCI completed surveys assessing physical and psychological functioning, demographic, pain-related and injury-related variables. Each version of the BPI and the GCP evidenced relatively high internal consistency (Cronbach’s alpha ranging from .86 to .96). The BPI composite scale scores were significantly related with average pain intensity (all rs ⬎ .60) and psychological functioning (all rs ⬎ ⫺.60), as were the BPI individual items (coefficient ranges ⫽ .43 to .59 and ⫺.30 to ⫺.65, respectively). The GCP score also demonstrated a significant association with pain intensity (r ⫽ .50) and psychological functioning (r ⫽ ⫺.55), as did the individual GCP items (coefficient ranges ⫽ .43 to.53 and ⫺.48 to ⫺.57, respectively). The findings support the validity and reliability of the original and modified BPI Interference scales and GCP Disability scale as measures of pain-related interference in persons with SCI and pain. The use of valid and reliable measures of pain-related interference could enhance communication between health care providers and patients regarding the impact of pain and help identify treatment strategies. Moreover, psychometrically sound measures are necessary to conduct informative treatment outcome research.
(933) Efficacy of alvimopan, a peripheral opioid receptor antagonist, for the management of gastrointestinal adverse events (GIAEs) associated with opioid use: Assessment using the PAC-SYM questionnaire B Morlion, N Aggarwal, L Frank, A Rentz, C Kleoudis, T Bell; GlaxoSmithKline, North Carolina, NC Opioids are the mainstay of therapy for persistent pain; however, the GIAEs associated with opioid use, including constipation, abdominal pain/bloating, reflux, and decreased appetite, continue to be inadequately treated. Furthermore, these GIAEs have a significant impact on quality of life. The efficacy and safety of alvimopan (0.5mg BID, 1mg QD, 1mg BID), a peripheral opioid receptor antagonist, were investigated in a 6-week, randomized, double-blind, placebo-controlled trial in patients with GIAEs taking opioids for persistent non-cancer pain (Study SB-767905/011; n⫽522). During the study, constipation symptoms were assessed using the Patient Assessment of Constipation (PAC-SYM) instrument – a 12-item questionnaire with three symptom domains (abdominal, rectal, stool). Patients completed the PAC-SYM using a 5-point Likert scale (higher scores⫽greater symptom severity) at randomization, weeks 1, 3 and 6, and at 2 weeks follow-up. The PAC-SYM was validated in this GIAE trial population and showed performance consistency, reliability, validity, and responsiveness comparable to that seen in the developmental study conducted in chronic idiopathic constipation.1 Total PAC-SYM scores were significantly improved in the alvimopan groups versus placebo (ⴱp⬍0.05; baseline scores in the placebo, alvimopan 0.5mg BID, 1mg QD and 1mg BID groups were 2.17, 2.12, 1.94 and 2.19, respectively, and decreased to 1.66, 1.28ⴱ, 1.25ⴱ, 1.35ⴱ at week 1; 1.49, 1.12ⴱ, 1.18 and 1.21ⴱ at week 3; and 1.62, 1.27ⴱ, 1.22 and 1.26ⴱ at week 6). In responder analysis, the percentage of patients with a 0.5/1.0 point decrease in total PAC-SYM score (indicating minimal clinically important difference/moderate clinical improvement) was significantly greater with alvimopan 0.5mg BID versus placebo (62%/43% versus 47%/26%; p⬍0.05). These patient-reported data were consistent with improvements in objectively measured symptoms. Alvimopan was well tolerated at all doses. The study results demonstrate that alvimopan significantly improves GIAEs in patients receiving opioids for persistent non-cancer pain. (1. Frank, Scand J Gastroenterol, 1999).
(936) The impact on reliability of scoring the brief pain inventory interference scale with fewer than eleven categories K Cook, K Johnson, D Amtmann; University of Washington, Seattle, WA The items of the Brief Pain Inventory (BPI) employs an 11-point scale that ranges from 0 (“Does not interfere”) to 10 (“Completely interferes”). The purpose of this study was to investigate the impact of collapsing adjacent response categories and scoring items as though they had fewer than 11 categories. BPI interference item responses were obtained from 235 persons with spinal cord injury, multiple sclerosis, or other neuromuscular disease. Adjacent response categories were collapsed to generate BPI scores based on 2, 3, 4, 5, 6, 7, 8, 9, 10 and 11 categories. The 10 sets of item responses (based on 2 through 11 categories) were calibrated to Andrich’s rating scale model, a Rasch model appropriate for Lickert-type items. The category structures obtained in the 10 calibrations were evaluated by plotting item category characteristic functions. In addition, the reliabilities of the scores were evaluated using two WINSTEPS-generated statistics, the person separation index and the person reliability index. The person separation index provides a ratio measure of “true” variance to error variance. The person reliability is somewhat equivalent to KR-20, Cronbach’s alpha, and the generalizability coefficient. The plots of the item category characteristic functions suggested that persons discriminate substantially fewer than 11 categories in rating their pain. The reliability and person separation results indicate some psychometric advantage to scoring based on at least 5 categories. No additional advantage was indicated for scoring based on more than 6 response categories.
S83
(931) Refer to Oral Paper Session 306
(934) Refer to Oral Paper Session 336
G04 - Clinical Outcomes Measurement
(935) Cognitive assessment in the fibromyalgia syndrome (FMS) using the Trail Making Test-B (TMTB)
(932) Reliability and validity of pain interference measures for persons with SCI
W Haynes, I Russell, J Michalek; The University Clinical Research Center, San Antonio, TX This study determined whether the TMTB would identify a cognitive defect among FMS patients compared with healthy normal controls (HNC). Primary FMS patients [1990 ACR criteria] and HNC were each studied between 8:00 am and noon on a single visit. Each subject was given three simple practice TMTs followed by the timed TMTB. The primary outcome variable was the time required to complete the exercise. Also documented were the numbers of errors and the product (time x errors). A by-group analysis of variance, adjusted for demographic variables, contrasted the mean scores for pain, anxiety, depression, function, stiffness and fatigue. A total of 151 subjects were enrolled (FMS N⫽90; HNC N⫽61]). Of the FMS, 84 were female, average age 50.6 years, and 72% Caucasian. The FMS were older (50.6 versus 44.7 years, p⫽0.009) than the HNC, had higher pain visual analog scale (38.6, vs. 2.9 mm), and more severe insomnia (7.3 cm versus 2.0 cm). For all subjects, FMS group took longer to complete the test (60.1 vs. 45 seconds, p⬍0.001) and made more errors than HNC (3.3 vs. 1.3, p⫽0.012), products (209.3 vs. 63.9, p⫽0.004). FMS not taking FMS medications (N⫽48) differed from HNC in time (60.5 vs. 45.1 seconds, p⫽0.008) but not in errors. FMS still taking FMS medications (N⫽42) took longer (60.0 vs. 45.3, p⬍0.001) and made more errors (3.6 vs.1.4, p⫽0.007), product (229.2 vs. 68.7, p⫽0.003). A matched analysis with 22 one-to-one demographically matched pairs produced similarly significant results. None of the clinical measures in either group correlated with the TMTB scores. These findings demonstrated that the TMTB was capable of detecting cognitive dysfunction in FMS. Use of FMS medications compounded this defect. Attempts to correlate these findings with clinical variables failed to disclose a logical model.
K Raichle, T Osborne, M Jensen; University of Washington School of Medicine, Seattle, WA There is a need to identify factors that are related to pain in persons with SCI that might be amenable to pain management interventions. Identification of such factors requires the use of psychometrically sound measures to assess important treatment outcome domains, such as pain interference. The current study examined the content validity and internal reliability of the Brief Pain Inventory (BPI) Interference scale, including the 7-item version, and modified 10- and 12-item versions, and the Graded Chronic Pain (GCP) Disability scale in a sample of persons with SCI and chronic pain. 157 participants with SCI completed surveys assessing physical and psychological functioning, demographic, pain-related and injury-related variables. Each version of the BPI and the GCP evidenced relatively high internal consistency (Cronbach’s alpha ranging from .86 to .96). The BPI composite scale scores were significantly related with average pain intensity (all rs ⬎ .60) and psychological functioning (all rs ⬎ ⫺.60), as were the BPI individual items (coefficient ranges ⫽ .43 to .59 and ⫺.30 to ⫺.65, respectively). The GCP score also demonstrated a significant association with pain intensity (r ⫽ .50) and psychological functioning (r ⫽ ⫺.55), as did the individual GCP items (coefficient ranges ⫽ .43 to.53 and ⫺.48 to ⫺.57, respectively). The findings support the validity and reliability of the original and modified BPI Interference scales and GCP Disability scale as measures of pain-related interference in persons with SCI and pain. The use of valid and reliable measures of pain-related interference could enhance communication between health care providers and patients regarding the impact of pain and help identify treatment strategies. Moreover, psychometrically sound measures are necessary to conduct informative treatment outcome research.
(933) Efficacy of alvimopan, a peripheral opioid receptor antagonist, for the management of gastrointestinal adverse events (GIAEs) associated with opioid use: Assessment using the PAC-SYM questionnaire B Morlion, N Aggarwal, L Frank, A Rentz, C Kleoudis, T Bell; GlaxoSmithKline, North Carolina, NC Opioids are the mainstay of therapy for persistent pain; however, the GIAEs associated with opioid use, including constipation, abdominal pain/bloating, reflux, and decreased appetite, continue to be inadequately treated. Furthermore, these GIAEs have a significant impact on quality of life. The efficacy and safety of alvimopan (0.5mg BID, 1mg QD, 1mg BID), a peripheral opioid receptor antagonist, were investigated in a 6-week, randomized, double-blind, placebo-controlled trial in patients with GIAEs taking opioids for persistent non-cancer pain (Study SB-767905/011; n⫽522). During the study, constipation symptoms were assessed using the Patient Assessment of Constipation (PAC-SYM) instrument – a 12-item questionnaire with three symptom domains (abdominal, rectal, stool). Patients completed the PAC-SYM using a 5-point Likert scale (higher scores⫽greater symptom severity) at randomization, weeks 1, 3 and 6, and at 2 weeks follow-up. The PAC-SYM was validated in this GIAE trial population and showed performance consistency, reliability, validity, and responsiveness comparable to that seen in the developmental study conducted in chronic idiopathic constipation.1 Total PAC-SYM scores were significantly improved in the alvimopan groups versus placebo (ⴱp⬍0.05; baseline scores in the placebo, alvimopan 0.5mg BID, 1mg QD and 1mg BID groups were 2.17, 2.12, 1.94 and 2.19, respectively, and decreased to 1.66, 1.28ⴱ, 1.25ⴱ, 1.35ⴱ at week 1; 1.49, 1.12ⴱ, 1.18 and 1.21ⴱ at week 3; and 1.62, 1.27ⴱ, 1.22 and 1.26ⴱ at week 6). In responder analysis, the percentage of patients with a 0.5/1.0 point decrease in total PAC-SYM score (indicating minimal clinically important difference/moderate clinical improvement) was significantly greater with alvimopan 0.5mg BID versus placebo (62%/43% versus 47%/26%; p⬍0.05). These patient-reported data were consistent with improvements in objectively measured symptoms. Alvimopan was well tolerated at all doses. The study results demonstrate that alvimopan significantly improves GIAEs in patients receiving opioids for persistent non-cancer pain. (1. Frank, Scand J Gastroenterol, 1999).
(936) The impact on reliability of scoring the brief pain inventory interference scale with fewer than eleven categories K Cook, K Johnson, D Amtmann; University of Washington, Seattle, WA The items of the Brief Pain Inventory (BPI) employs an 11-point scale that ranges from 0 (“Does not interfere”) to 10 (“Completely interferes”). The purpose of this study was to investigate the impact of collapsing adjacent response categories and scoring items as though they had fewer than 11 categories. BPI interference item responses were obtained from 235 persons with spinal cord injury, multiple sclerosis, or other neuromuscular disease. Adjacent response categories were collapsed to generate BPI scores based on 2, 3, 4, 5, 6, 7, 8, 9, 10 and 11 categories. The 10 sets of item responses (based on 2 through 11 categories) were calibrated to Andrich’s rating scale model, a Rasch model appropriate for Lickert-type items. The category structures obtained in the 10 calibrations were evaluated by plotting item category characteristic functions. In addition, the reliabilities of the scores were evaluated using two WINSTEPS-generated statistics, the person separation index and the person reliability index. The person separation index provides a ratio measure of “true” variance to error variance. The person reliability is somewhat equivalent to KR-20, Cronbach’s alpha, and the generalizability coefficient. The plots of the item category characteristic functions suggested that persons discriminate substantially fewer than 11 categories in rating their pain. The reliability and person separation results indicate some psychometric advantage to scoring based on at least 5 categories. No additional advantage was indicated for scoring based on more than 6 response categories.