Extent of sleep problems and relationship with severity of chronic pain using three validated sleep assessment tools

Objective Chronic pain can impact on sleep, but the extent and nature of sleep problems in patients with chronic pain are incompletely clear. Several validated tools are available for sleep assessment but they each capture different aspects. We aimed to describe the extent of sleep issues in patients with chronic non-malignant pain using three different validated sleep assessment tools and to determine the relationship of sleep issues with pain severity recorded using the Brief Pain Inventory (BPI), a commonly used self-assessment tool in pain clinics. The BPI has a single question on the interference of pain on sleep and we also compared this with the validated sleep tools. Design Prospective, cross-sectional study. Setting Pain management clinic at a large teaching hospital in the United Kingdom. Subjects Adult patients (with chronic non-malignant pain of at least 3 months’ duration) attending clinic during a 2-month period. Methods Participants completed the Pittsburgh Sleep Quality Index (PSQI), the Pain and Sleep Questionnaire-3 (PSQ-3) and the Verran Snyder-Halpern (VSH) sleep scale, plus the BPI. Duration and type of pain, current medications and demographic data were recorded. Results We recruited 51 patients and 82% had poor sleep quality as shown by PSQIscores above five. PSQI ( p = 0.0002), PSQ-3 ( p = 0.0032), VSH sleep efficiency ( p = 0.012), sleep disturbance ( p = 0.0014) and waking after sleep onset ( p = 0.0005) scores were associated with worse BPI pain scores. BPI sleep interference scores concurred broadly with the validated sleep tools. Median [range] sleep duration was 5.5 [3.0–10.0] hours and was also related to pain score ( p = 0.0032). Conclusion Chronic pain has a marked impact on sleep regardless of the assessment tool used. The sleep interference question in the BPI could be used routinely for initial identification of sleep problems in patients with chronic pain.

A Crossover Design for Comparative Efficacy: A 28 Days-Randomized Clinical Trial of Cognitive Behavioral Therapy for Chronic Pain of Degenerative Conditions

In physiotherapy practice, a number of patients are known to suffer from chronic pain which results in reduced activity levels, interference in sleep, enjoyment of life, mood, and relations with others. Cognitive behavioral therapy, in this aspect will provide a holistic approach to the available treatment. Cognitive behavioral therapy has also been shown to target cognitive distortions such as pain catastrophizing, fear avoidance, overgeneralizing and others, all the while improving physical health, activity levels and quality of life. This study assessed the efficacy of cognitive behavioral therapy in the management of patients with chronic pain at the University Teaching Hospitals in Zambia. A randomized clinical trial utilizing a crossover design was utilized for the study. A random sample of 32 participants was used in the study after fulfilling the study criteria. Data was analyzed using ANCOVA with alpha of 0.05. The study recorded small effects in the reduction of pain intensity in both phase one and two. In phase one, it also recorded small effects in general work interference, sleep interference and enjoyment of life interference but recorded medium effects in normal work interference and mood interference. Phase two of the study recorded small effect size in reduction of general work interference, normal work interference, mood interference, relations with others interference, sleep interference and Enjoyment of Life interference. Cognitive behavioral therapy ensures the management of chronic pain addresses areas in which an individual is affected by pain and which in turn exacerbate the chronic pain. Physiotherapy provides a more holistic approach when used in conjunction with cognitive behavioral therapy.

Effect of Concomitant Pain Medications on Response to Pregabalin in Patients with Postherpetic Neuralgia or Spinal Cord InjuryRelated Neuropathic Pain

Background: Patients with neuropathic pain (NeP) often receive combination therapy with multiple agents in the hopes of improving both pain and any comorbidities that may be present. While pregabalin is often recommended as a first-line treatment of NeP, few studies have examined the effects of concomitant medications on the efficacy of pregabalin. Objective: To examine the effects of concomitant medications on the efficacy and safety of pregabalin for the treatment of NeP. Study Design: Data were derived from 7 randomized placebo-controlled trials of pregabalin (150, 300, 600, and flexible 150 – 600 mg/d) for the treatment of postherpetic neuralgia (PHN) and 2 randomized placebo-controlled trials for the treatment of NeP due to spinal cord injury (SCINeP). On each day, patients rated the severity of their pain and pain-related sleep interference (PRSI) over the previous 24 hours on a scale from 0 to 10, with higher scores indicating greater severity. Patients were also continually monitored for the occurrence of adverse events. Setting: A pooled retrospective analyses of data from randomized clinical trials. Methods: Changes from baseline in mean weekly pain and PRSI scores were compared between patients who received concomitant NeP medications and patients who did not receive concomitant NeP medications. Results of these comparisons are presented separately for the PHN (through 4, 8, and 12 weeks) and SCI-NeP (through 12 weeks) cohorts. Common adverse events are also presented for each treatment group. Results: Pregabalin significantly improved both pain and PRSI scores relative to placebo at most dose levels and time points examined. Notably, little difference was observed in the extent of therapeutic response to pregabalin between patients who received concomitant NeP medications and patients who did not receive concomitant NeP medications. Additionally, the profile of treatment-emergent adverse events appeared to be largely unaffected by the use of concomitant NeP medications in the pooled patient population. Limitations: Our analysis is limited in that the original trials of pregabalin were not powered to examine the effects of concomitant NeP medications. Conclusions: The data presented here demonstrate that therapeutic response to pregabalin and the occurrence of adverse events in patients with NeP are generally unaffected by the concurrent use of other NeP medications. Trial Registration numbers: NCT00159666; NCT00301223; NCT00407745 Key words: Pregabalin, neuropathic pain, pain-related sleep interference, concomitant medications, postherpetic neuralgia, spinal cord injury, efficacy, safety

Confirmatory factor analysis of 2 versions of the Brief Pain Inventory in an ambulatory population indicates that sleep interference should be interpreted separately

BackgroundThe Brief Pain Inventory (BPI-SF) is a widely-used generic pain interference scale, however its factor structure remains unclear. An expanded 10-item version of the Interference subscale has been proposed, but the additional value of the 3 extra items has not been rigorously evaluated. The purpose of this study was to evaluate and contrast the factorial and concurrent validity of the original 7-item and 10-item versions of the BPI-SF in a large heterogeneous sample of patients with chronic pain.MethodsExploratory and confirmatory factor analyses were conducted on independent subsets of the sample, and concurrent correlations with scales capturing similar constructs were evaluated.ResultsTwo independent exploratory factor analyses (n = 500 each) supported a single interference factor in both the 7- and 10-item versions, while confirmatory factor analysis (N =1000) suggested that a 2-factor structure (Physical and Affective) provided better fit. A 3-factor model, where sleep interference was the third factor, improved in model fit further. There was no significant difference in model fit between the 7- and 10-item versions. Concurrent associations with measures of general health, pain intensity and pain-related cognitions were all in the anticipated direction and magnitude and were not different by version of the BPI-SF.Conclusions and implicationsThe addition of 3 extra items to the original 7-item Interference subscale of the BPI-SF did not improve psychometric properties. The combined results lead us to endorse a 3-factor structure (Physical, Affective, and Sleep Interference) as the more statistically and conceptually sound option.