Cognitive function in older patients with postherpetic neuralgia.

BACKGROUND AND AIMS: Neuropathic pain has been shown to be accompanied by cognitive impairment, but the specific impact of postherpetic neuropathic pain on cognitive processes has not been explored. This study aims to evaluate the impact of pain on several domains of cognition in older patients with postherpetic neuralgia (PHN). METHODS: This cross-sectional study (clinicaltrial.gov NCT 00989040) included 84 individuals after signature of informed consent. PARTICIPANTS: 42 patients with PHN and 42 healthy volunteers. Of the 42 PHN patients, 21 received systemic treatment (antidepressants, anticonvulsants, opiates) and 21 had topical treatment with the 5% lidocaine medicated plaster. All participants performed a panel of four cognitive tests: reaction time, semantic memory, decision-making, and visual memory (Cantab, Cambridge). RESULTS: Forty men and 44 women with a mean age of 72 ± 8 years participated. Each PHN patient was matched by age and gender with a healthy volunteer. Vigilance, decision-making, and semantic memory were significantly impaired (P < 0.05) in patients on systemic treatment, especially with antidepressants, while no significant changes were noted between the lidocaine plaster group and their matched controls of healthy volunteers. CONCLUSION: This study shows the deleterious effect of systemic PHN treatment on several domains of cognition. Cognitive impairment associated with pain and antidepressants may be reversed by topical pain management. Topical treatment with 5% lidocaine medicated plaster is a valuable alternative for pain alleviation and maintains cognitive integrity in this vulnerable population.

Treatment of neuropathic pain with 5% lidocaine-medicated plaster: Five years of clinical experience.

BACKGROUND: Neuropathic pain is often severe and adversely affects patients' quality of life. OBJECTIVE: To perform a retrospective, observational study investigating the efficacy and safety of treating refractory chronic neuropathic pain with 5% lidocaine-medicated plaster, in patients attending pain centres. METHODS: Medical records from 467 patients treated with 5% lidocaine-medicated plaster were evaluated for efficacy (maximum and minimum pain intensities and coanalgesic consumption) and adverse events. Data from an initial assessment and at least one follow-up visit had to be available, and separate analyses were conducted for the general population and the subpopulation older than 70 years of age. RESULTS: Of the patients enrolled, 25.0% were older than 70 years of age. While 20.6% had postherpetic neuralgia, 76.3% had other types of peripheral pain. Approximately 78.1% of cases of peripheral neuropathic pain followed surgery, and 23% were post-traumatic pain. The time from onset to referral was more than one year in two- thirds of cases. All patients experienced pain of at least moderate severity (mean [± SD] 11-point numerical rating scale score 5.2 ± 2.4 to 8.2 ± 1.6). Treatment with 5% lidocaine-medicated plaster reduced pain intensity by more than 50% in 45.5% of patients, and by at least 30% in 82.2%. Of note, the consumption of analgesics and coanalgesics was significantly reduced. Results were similar in both the general population and the subpopulation older than 70 years of age, at high risk and often receiving multiple medications. CONCLUSIONS: Treatment of refractory neuropathic pain with 5% lidocaine-medicated plaster clearly demonstrated efficacy and an excellent safety profile in patients with refractory neuropathic pain.

Electronic and paper versions of a faces pain intensity scale: concordance and preference in hospitalized children.

BACKGROUND: Assessment of pain in children is an important aspect of pain management and can be performed by observational methods or by self-assessment. The Faces Pain Scale-Revised (FPS-R) is a self-report tool which has strong positive correlations with other well established self-report pain intensity measures. It has been recommended for measuring pain intensity in school-aged children (4 years and older). The objective of this study is to compare the concordance and the preference for two versions, electronic and paper, of the FPS-R, and to determine whether an electronic version of the FPS-R can be used by children aged 4 and older. METHODS: The study is an observational, multicenter, randomized, cross-over, controlled, open trial. Medical and surgical patients in two pediatric hospitals (N=202, age 4-12 years, mean age 8.3 years, 58% male) provided self-reports of their present pain using the FPS-R on a personal digital assistant (PDA) and on a paper version. Paper and electronic versions of the FPS-R were administered by a nurse in a randomized order: half the patients were given the PDA version first and the other half the paper version first. The time between the administrations was planned to be less than 30 minutes but not simultaneous. Two hundred and thirty-seven patients were enrolled; 35 were excluded from analysis because of misunderstanding of instructions or abnormal time between the two assessments. RESULTS: Final population for analysis comprised 202 children. The overall weighted Kappa was 0.846 (95%CI: 0.795; 0.896) and the Spearman correlation between scores on the two versions was rs=0.911 (p<0.0001). The mean difference of pain scores was less than 0.1 out of 10, which was neither statistically nor clinically significant; 83.2% of children chose the same face on both versions of the FPS-R. Preference was not modified by order, sex, age, hospitalization unit (medical or surgical units), or previous analgesics. The PDA was preferred by 87.4% of the children who expressed a preference. CONCLUSION: The electronic version of the FPS-R can be recommended for use with children aged 4 to 12, either in clinical trials or in hospitals to monitor pain intensity.

Development and validation of a questionnaire assessing volitional competencies to enhance the performance of physical activities in chronic low back pain patients.

BACKGROUND: Motivation has long been emphasized as the most important determinant of action. However, there is a substantial gap between people's goals and their attainment. Patients may be motivated and yet unable to take action if their volitional competencies are insufficient. One of the important tasks of volition is goal-maintenance. Research has stressed the importance of a volitional tool, the implementation intentions. Implementation intentions indicate where, when, and how the action leading to the goal will be performed. Forming implementation intentions favours the execution of goal-directed efforts, and reinforces the relationship between intentions and behaviours. Results from various studies clearly suggest that volitional competencies and implementation intentions could play a role in low back pain (LBP) patients. However, there is at present no questionnaire allowing assessing the capacity of implementation intentions of physical activities in LBP patients. METHODS/DESIGN: This study will develop such a questionnaire, using a 3-step approach. A first qualitative step to build categories and generate items; 30 patients suffering chronic LBP will be invited to participate in semi-structured interviews; verbatim and derived items will then be submitted to a panel of experts, using a Delphi method; a second quantitative step to examine the properties of items, and determine the factorial structure of the questionnaire; 100 patients suffering chronic LBP will be recruited to respond to this phase; and third, preliminary psychometric analyses (item-scale correlations, construct validity, reliability); 180 chronic LBP patients will be recruited for this phase of the study. The relationships between implementation intentions and variables affecting physical activity on chronic LBP patients, i.e. pain, physical capacities, fear-avoidance beliefs, kinesiophobia, work status, and level of physical activity will be considered. DISCUSSION: Developing a questionnaire to assess implementation intentions would allow investigating the role of these intentions in the transition from acute to chronic LBP. The results of this study should contribute to the understanding of the psychological processes at stake in the development of chronic LBP, and in particular to the identification of factors eventually favouring patients' participation in and adherence to active physical treatments.

Ecological or recalled assessments in chronic musculoskeletal pain? A comparative study of prospective and recalled pain assessments in low back pain and lower limb painful osteoarthritis.

OBJECTIVES: The objective of this study was to compare ecological and recalled pain intensity assessments over 29 days in hip and knee osteoarthritis (O) and chronic low back pain (L). PATIENTS AND METHODS: Rheumatologists were asked to enroll patients with O and L, with pain intensity above 40 mm, in a prospective study for 29 days. Pain intensity was assessed with physicians on Days 1 and 29, and ecologically, over the intervening 28-day period, by random phone calls. RESULTS: We carried out correlation analyses for 353 (159 O, 194 L) patients: Overall recalled daily pain was strongly correlated with calculated 3-day mean pain assessments (r=0.96 [O]; 0.93 [L]) and evening pain (r=0.96 [O], 0.90 [L]). Correlations between ecological and recalled measures were stronger for recall over the last 7 days than for recall over the last 28 days in osteoarthritis patients (r=0.78, r=0.63), but were similar for both recall periods in low back pain patients (r=0.70, r=0.72). Correlations between assessments for the last 7 and 28 days were stronger for ecological (r=0.88 [O], 0.91 [L]) than for clinical (r=0.77 [O]; 0.86 [L]) assessments. After adjustment for current pain intensity, correlations remained significant for ecological assessments, but not for clinical assessments. Recalled pain assessments were more accurate when made after 24 hours (r=0.71 [O]; 0.70 [L]) than when made after 48 hours (r=0.63 [O]; 0.61 [L]). CONCLUSIONS: For both low back pain and osteoarthritis, overall daily pain recall is a reliable measurement correlated with daily ecological measurements, whereas a rapid decrease in recall occurs after 48 hours. The most reliable period for pain recall was 7 days, but the results obtained were influenced by current pain.

Comparison of daily, weekly or monthly pain assessments in hip and knee osteoarthritis. A 29-day prospective study.

OBJECTIVE: To compare the accuracy of daily and recalled pain measurements in hip and knee osteoarthritis (OA). METHODS: A prospective study investigating pain intensity over 29 days in patients with painful OA. Pain was assessed on days 1 and 29 during visits. Between these two visits, daily (worst, least, usual, mean, at rest and during daily life) and recalled pain intensities were randomly recorded by telephone interview with a numerical rating scale. RESULTS: We studied 129 patients, with a mean age of 67.7 ± 10.0 years, 27.1% males. Daily prospective assessments demonstrated that the strongest correlations were between 'mean daily' and 'usual' pain (r=0.88) and between 'mean daily' and 'worst' pain (r=0.86). Retrospective assessments demonstrated a strong correlation between recalled pain intensities and calculated mean of daily assessments over the seven and 28 days (0.78 and 0.67, respectively), but weakened by adjustment for pain intensity on the day of recalled pain assessment. Anxiety and depression scores did not affect pain recall for 7 and 28 days. CONCLUSIONS: In hip and knee OA, prospective daily pain assessment can be performed either by assessing 'usual pain' or 'worst pain' of the day. When recalled over one and four weeks, recall pain intensity is well correlated with calculated mean of prospective daily pain assessments during the same period, but correlations are weaker as the length of period increases. Either for 1 and 4 weeks, retrospective assessments are influenced by current pain intensity at the end of the period.

Is volition the missing link in the management of low back pain?

Patients with nonspecific chronic low back pain are typically prescribed a regimen of regular physical exercises to improve pain and function, increase workability, and prevent pain recurrence. However, adherence to home exercise programs is often partial at best. Patients often fail to translate their intention to exercise (motivation) into action (implementation). Volition is the mental activity by which intentions are implemented. In this review, we argue that volition may be crucial to the successful rehabilitation of patients with low back pain. Obstacles to the implementation of intentions are described, as well as factors that promote implementation, most notably the conscious formation of implementation intentions.

Influence of time, activities, and memory on the assessment of chronic low back pain intensity.

STUDY DESIGN: A prospective study. OBJECTIVE: To identify factors potentially influencing patient self-evaluation of chronic low back pain (CLBP) and their interactions. SUMMARY OF BACKGROUND DATA: The impact of the time, context, and/or recall on the self-assessment of chronic pain intensity remains poorly understood. METHODS: A prospective study investigated patients' CLBP intensity over 29 days. Patients were evaluated on days 1 and 29 by the investigator with a pain intensity visual analog scale (0-100), and interviewed by phone on days 8, 15, and 22 to 28 to evaluate pain intensity with a numerical rating scale (0-10), either thrice daily (time-associated group), or during rest/activities (activity-associated group). Current and/or recalled pain intensities were also assessed. Means of recorded pain intensity and overall assessment of patient's pain intensity of the day were subjected to statistical analyses with analysis of variance and test of correlation. RESULTS: Among the 203 patients included, 194 (56.2% women; mean age: 47.5 +/- 12.1 year) were considered in the analysis (9 patients were not followed until day 24). Strong correlations were obtained between mean pain intensity (time-associated group = 44 patients) and overall assessment of pain intensity of the day. Strong correlations were also obtained between overall assessment of pain intensity of the day and intensity measured during each activity, but not between current pain intensity and remembered pain 24 of 48 hours earlier (activity-associated group = 150 patients). Recalled pain intensities for the last 7 or 28 days were strongly correlated with current pain intensity, but the correlations were markedly weaker after adjustment for day 29-pain intensity. CONCLUSION: For CLBP patients, overall assessment of pain intensity of the day at evening is accurate to assess pain on 1 day. Overall assessment of pain intensity of the day is very close with usual pain. Furthermore, 24 and 48 hours remembered pain intensity are not accurate measures. Recalls of pain on the 7 or 28 last days were very dependant of the pain intensity of the day of the assessment. These findings could contribute to improving pain intensity assessment in CLBP patients avoiding multiple assessments, especially during clinical trials.