S14 The Journal of Pain Abstracts

(152) The perceived control over pain construct in painmanage-ment outcomes for African Americans with cancer pain

A Vallerand, T Templin, S Schim, S Hasenau, and S Robinson; Wayne StateUniversity, Detroit, MI

The purpose of this study was to explore model development among the con-structs Pain, Perceived Control Over Pain (PCP), and Functional Status in AfricanAmerican patients with cancer pain. Participants (N=156) were African Amer-ican men (40%) and women patients attending an urban comprehensive can-cer center clinic in the Midwest and who reported experiencing moderate tosevere pain within the past twoweeks (M age=55.9). The analysis used the firstwave of data from a longitudinal study that is still in progress. Pain and func-tional status were measured with items from the Brief Pain Inventory. PCPwas a latent factor defined by four scales– Survey of Pain Attitudes, ControlSubscale; Pain Catastrophizing Scale; Acceptance of Pain Survey; and PerceivedControl Scale. Because these four variables have not been used this way before,a confirmatory factor analysis measurement model was examined first. Meanworst pain scores for the past week were 7.7. Younger patients and women re-ported more pain. Pain scores did not differ by years since diagnosis or metas-tasis. Themeasurementmodel fit well and all loadingswere significant (p<.05),confirming that the variables defining PCP were contributing as expected. Themediationmodel also fit well (RMSEA=.056, CFI=.96). The direct effects of painon functional status (path=.50) and indirect effects of pain through perceivedcontrol were significant (p < .05; path coefficients were -.56 for Pain/PCP, and-.30 for PCP/ Functional Status). The mediation was partial but strong,accounting for a reduction of 25% in the effects of pain on functional status.The results support the author’s four component conceptualization ofperceived control over pain. Functional status for patients with pain was medi-ated by perceived control. Improving perceived control over pain has thepotential for improving patients’ psychological and physical functioning andultimately improving their lives. Funding NCI R01 CA149432-01A1.

(153) A review of predicting chronicity in patients with acute orsub-acute low back pain

J Boissoneault, M Robinson, and S George; University of Florida, Gainesville, FL

The approximately 10% of patients with acute low back pain whose painbecomes chronic are responsible for disproportionate health care costs. Thus,accurately predicting the transition from acute to chronic low back pain is ofsignificant importance. We conducted a review of prospective studies directlyinvestigating prognostic factors for the transition from acute to chronic lowback pain in order to consider and evaluate the quality of predictive models,and the progress in this important area of study. Studieswith follow-up periodsless than one year as well as clinical trials were excluded. Key classes of predic-tors, primary outcomes, and analytic strategies were identified. PubMedsearches using combinations of terms including ‘‘low back pain’’, ‘‘acute tochronic’’, ‘‘persistent pain’’, and ‘‘chronicity’’ were conducted. 16 research re-ports meeting these criteria were identified from search hits and their refer-ence lists. Significant heterogeneity in study characteristics was noted.Primary outcomes included disability (6 studies), pain intensity (4 studies),return-to-work (3 studies), or other outcomes (3 studies). 13/16 studies dichot-omized patients into recovered vs. not, employing logistic regression ordiscriminant analysis to test models’ predictive power; 5/16 used multipleregression for continuous outcomes. Accuracy for discriminant analyses rangedfrom 77% to 91%. Variance in outcome measures accounted for by multipleregression models ranged from 28% to 69%. Although variation in methodol-ogy is expected given the specific goals of each study, discrepancies observedbetween studies make direct comparisons of models predicting the transitionfrom acute or sub-acute low back pain difficult. Furthermore, the heterogene-ity of predictors and outcome measures suggest that optimal, inclusive predic-tion models have not yet been tested. Suggestions to move the field forward,including the need for more consistent criteria for recovery across studies, areprovided in the Discussion.

(154) Themoderating effect of sleep fragmentation on the asso-ciation of sleep duration and pain in adults with sickle celldisease

G Moscou-Jackson, P Finan, C Campbell, and J Haythornthwaite; JohnsHopkins University School of Nursing, Baltimore, MD

Poor sleep is typically inversely associated with pain severity. However, the in-fluence of sleep architecture on clinical pain has not yet been systematicallyinvestigated in adults living with Sickle Cell Disease (SCD). Daily diaries arethe gold standard for assessing time-variant fluctuations of sleep and pain indaily life. The purpose of the present studywas to examine the relationship be-tweendaily reports of SCDpain andparameters of sleep architecture, includingtotal sleep time (TST), sleep onset latency (SOL), and wake after sleep onset(WASO). It was hypothesized that the relationship between TST and SCD painwould be qualified by levels of sleep fragmentation (i.e., WASO) and latency.Seventy-seven (77) adults with SCD completed daily morning (sleep) and eve-ning (pain) diaries over a three-month period. Hierarchical linear model(HLM) with a random intercept was used to examine daily between-subjectsand within-subjects effects of TST on SCD pain, as well as moderating effectof changes in WASO and SOL on pain over the study period. Results of theHLM analysis confirmed an inverse main effect of TST on self-reported painwhereby increasing TST was associated with decreased pain severity. Analysesalso revealed a negative moderating effect of WASO, but not SOL, on the dailyrelationship between TST and pain. The moderating effect of WASO remainedsignificant even after controlling for baseline depression and pain anxiety, twocharacteristics which are known to be positively associated with pain severity.These results suggest that both sleep duration and sleep fragmentation areassociated with self-reported pain in adults with SCD. In particular, increasedsleep duration has a positive effect on self-reported pain, but sleep fragmenta-tion may diminish this effect. Taken together, the results suggest that reducingsleep fragmentation (WASO) may increase the positive benefit of increasedsleep duration on pain.

(155) Evaluation of the relationship among pain, fear of painand anxiety in patients with chronic pain

P Knotek, J Raudenska, and H Knotkova; University Hospital Motol, Prague,Czech Republic

Findings from research studies suggest that chronic pain can lead to substantialchanges in patients’ affective states and cognition. In our previous work, wedeveloped a model of psychological changes in chronic pain. Now we aim totest interactions among Pain, Fear of Pain and Cognitive Processing/Evaluationof Pain. 272 outpatients with nonmalignant chronic pain (108 M, 164 F, meanage [SD] 48 [10.7] and 47 [11.1] years), from the Center for Pain Managementand Research, University Hospital, Motol, Prague, provided self-reports tothe Czech versions of the following instruments: Visual Analogue Scale –PainIntensity and Pain Unpleasantness (VAS-I; VAS-U), Fear and Observation ofPain Inventory, and State-Trait Anxiety Inventory. The model with Fear ofPain as a dependent variable, Pain (Intensity, Unpleasantness), Cognitive Pro-cessing of Pain (My Fault, Fault of Others, Permanence) and Anxiety-Trait aspredictors was tested using the software EQS 6, regression modeling, and theRootMean Square Error of Approximation (RMSEA) and Confirmatory Fit Index(CFI) were used as the fit indexes. Statistical analysis yielded the followingregression coefficients: Cognitive Processing of Pain – Fear of Pain 0.84; Pain– Fear of Pain 0.07; Anxiety – Fear of Pain 0.31; and a covariance 0.31 was de-tected between Anxiety and Permanence, a variable of Cognitive Processingof Pain; CFI = 0.95; RMSEA = 0.10. In conclusion, the results indicate that pa-tients’ cognitive interpretation of pain and its meaning may be a strongertrigger for pain-related fear than pain intensity. Therefore, decreasing pain in-tensity in chronic pain patients might not be sufficient tomitigate pain-relatedfear, and psychological interventions addressing patients’ interpretation ofpain should be considered.