Neuropathic pain in rheumatoid arthritis and its association with Afro-descendant ethnicity: a hierarchical analysis.

BACKGROUND: nociceptive pain from joint damage caused by autoimmune inflammatory disease is expected in rheumatoid arthritis. However, neuropathic pain also occurs and persists even with the disease under control. This study aimed to investigate factors associated with neuropathic pain in rheumatoid arthritis by considering sociodemographic and behavioral data as well as lifestyle and clinical aspects in a self-referenced afro-descendant ethnicity sample. METHODS: In a cross-sectional study, the Douleur Neuropathique 4, Health Assessment Questionnaire, the Hospital Anxiety and Depression Scale and sociodemographic characteristics were used. Additionally, a Bivariate analysis was performed, followed by hierarchical multiple logistic regression, with results expressed as odds ratio and 95% confidence intervals. RESULTS: the frequency of NP was at a proximal level consisting of clinical characteristics related to anxiety (p=0.03) and depression (p=0.04). When a hierarchical multiple logistic regression analysis was conducted, an independent association was identified between neuropathic pain and black race. At the third and fourth stages, when the clinical variables were adjusted by race, an association was found with moderate functionality (p=0.04) and anxiety (p=0.04). CONCLUSION: neuropathic pain in rheumatoid arthritis is related to the Afro-descendant ethnicity that affects functionality and anxiety levels.

Psychological Factors Associated With Painful Versus Non-Painful HIV-Associated Sensory Neuropathy.

HIV-associated sensory neuropathy (HIV-SN) is a common, and frequently painful complication of HIV, but factors that determine the presence of pain are unresolved. We investigated: (i) if psychological factors associated with painful (n = 125) versus non-painful HIV-SN (n = 72), and (ii) if pain and psychological factors affected quality of life (QoL). We assessed anxiety and depression using the Hopkins Symptoms Checklist-25. Pain catastrophizing and QoL were assessed using the Pain Catastrophizing Scale and Euroqol-5D, respectively. Presence of neuropathy was detected using the Brief Neuropathy Screening Tool, and pain was characterised using the Wisconsin Brief Pain Questionnaire. Overall, there was a high burden of pain, depression and anxiety in the cohort. None of the psychological variables associated with having painful HIV-SN. Greater depressive symptoms and presence of pain were independently associated with lower QoL. In those participants with painful HIV-SN, greater depressive symptom scores were associated with increased pain intensity. In conclusion, in a cohort with high background levels of psychological dysfunction, psychological factors do not predict the presence of pain, but both depression and presence of pain are associated with poor quality of life.

Validity and reliability of the persian (Farsi) version of the DN4 (Douleur Neuropathique 4 Questions) questionnaire for differential diagnosis of neuropathic from non-neuropathic pains.

The aim of our study was translation and assessment of validity and reliability of the Persian version of DN4 questionnaire. The goal was to fill the gap caused by the absence of a validated instrument in Persian to facilitate discrimination of neuropathic pain. In this study, the adaptation and validation of the questionnaire was carried out in 4 steps, including translation, retranslation, semantic, and literal assessments, and a pilot study for practicability and potential perception difficulties of the final Persian version on 45 patient samples. The questionnaire validation performed on 175 patients, 112 (64%) females with the mean age of 52.53 (SD = 14.98) ranging from 22 to 87 years of age with neuropathic (N = 86) and non-neuropathic pain (NNP) (N = 89). Sensitivity, specificity, and Youden Index in cut-off point ≥ 4 were 90%, 95%, and 0.85, respectively, which are noteworthy findings among other validation studies. The Cronbach's alpha coefficient of the whole questionnaire was 0.852. Inter-rater agreement and test-retest reliability were significant intraclass coefficient (ICC = 0.957 and ICC = 0.918, respectively). The Persian version of DN4 questionnaire is a reliable, valid, feasible, and easily administered tool for precise discrimination neuropathic pain from NNP in Farsi. The characteristics of this test can assist practitioner to diagnose neuropathic pain accurately for both clinical and research purposes.

Cross-Cultural Psychometric Assessment of the Leeds Assessment of Neuropathic Symptoms and Signs (LANSS) Pain Scale in the Portuguese Population.

BACKGROUND: Chronic pain is a well-known phenomenon. The differential diagnosis between neuropathic and nociceptive pain syndromes is a challenge. Consequently, assessment instruments that can distinguish between these conditions in a standardized way are of the utmost importance. The Leeds Assessment of Neuropathic Symptoms and Signs (LANSS) is a screening tool developed to identify chronic neuropathic pain. The aim of this study was the Portuguese language translation, linguistic adaptation of the LANSS pain scale, its semantic validation, internal consistency, temporal stability, as well its validity and discriminative power. METHODS: LANSS Portuguese version scale was applied to 165 consecutive patients attending the pain clinic: 103 fulfilled the clinical criteria for the diagnosis of pain of neuropathic origin and the remaining 62 fulfilled the criteria for nociceptive pain. RESULTS: The scale proved to be an internally consistent (Cronbach's alpha = 0.78) and reliable instrument with good test-retest stability (r = 0.7; P < 0.001). However, its validity and specificity with a cutoff point of ≥ 12, for differentiating patients with neuropathic pain from those with non-neuropathic pain, had 89% sensitivity, 74% specificity, positive predictive value of 85%, and negative predictive value of 81%. CONCLUSIONS: The Portuguese LANSS version pain scale properties lead us to the conclusion that such a cross-cultural version is a reliable and valid instrument for the differentiation of this type of pain. Its usage is recommended.

Ethnic differences in oro-facial somatosensory profiles-quantitative sensory testing in Chinese and Danes.

Ethnic differences in pain experiences have been widely assessed in various pathological and experimental conditions. However, limited sensory modalities have been described in previous research, and the affective-motivational factors have so far been estimated to be the main mediator for the ethnic differences. This study aimed to detect the ethnic differences of oro-facial somatosensory profiles related to the sensory-discriminative dimension in healthy volunteers. The standardised quantitative sensory testing battery developed by the German Research Network on Neuropathic Pain was performed bilaterally in the infraorbital and mental regions on age- and gender-matched healthy Chinese and Danes, 29 participants each group. The influences of ethnicity, gender and test site on the somatosensory profile were evaluated by three-way anova. The ethnic disparities were also presented by Z-scores. Compared to Danes, Chinese were more sensitive to thermal detection, thermal pain, mechanical deep pain and mechanical pain rating parameters (P < 0·002) related to small fibre functions. However, the inverse results were observed for mechanical tactile modality related to large fibre function (P < 0·001) and wind-up ratio (P = 0·006). Women presented higher sensitivity compared to men. The mean Z-scores of all the parameters from Chinese group were in the normal zone created by Danish Caucasians' means and SDs. The ethnic disparities in somatosensory profile illustrated the necessity of establishing the reference data for different ethnic groups and possibly individual pain management strategies for the different ethnic groups.

Identification of patients with neuropathic pain using electronic primary care records.

BACKGROUND: Chronic neuropathic pain is a common condition which is challenging to treat. Many people with neuropathic pain are managed in the community, so primary care records may allow more appropriate subjects to be recruited for clinical studies. OBJECTIVE: We investigated whether primary care records can be used to identify patients with diseases associated with neuropathic pain. METHOD: We analysed demographic, diagnostic and prescribing data from over 100 000 primary care electronic patient records in one part of London, UK. RESULTS: The prevalence of diagnoses associated with chronic neuropathic pain was 13 per 1000, with the elderly, women and white patients experiencing the greatest burden of disease. CONCLUSION: Computerised health records offer an excellent opportunity to improve the identification of patients for clinical research in complex conditions like chronic neuropathic pain. To make full use of data from these records, standardisation of clinical coding and consensus on diagnostic criteria are needed.

Sensitivities to Thermal and Mechanical Stimuli: Adults With Sickle Cell Disease Compared to Healthy, Pain-Free African American Controls.

Evidence supports, but is inconclusive that sensitization contributes to chronic pain in some adults with sickle cell disease (SCD). We determined the prevalence of pain sensitization among adults with SCD pain compared with pain-free healthy adults. In a cross sectional, single session study of 186 African American outpatients with SCD pain (age 18-74 years, 59% female) and 124 healthy age, gender, and race matched control subjects (age 18-69 years, 49% female), we compared responses to standard thermal (Medoc TSA II) and mechanical stimuli (von Frey filaments). Although we observed no significant differences in thermal thresholds between controls and patients, patients with SCD had lower pain thresholds to mechanical stimuli and reported higher pain intensity scores to all thermal and mechanical stimuli at a non-painful body site. Compared with controls, about twice as many patients with SCD showed sensitization: 12% versus 23% at the anterior forearm site (P = .02), and 16% versus 32% across 3 tested sites (P = .004). Among patients with SCD, 18% exhibited some element of central sensitization. Findings indicate that persistent allodynia and hyperalgesia can be part of the SCD pain experience and should be considered when selecting therapies for SCD pain. PERSPECTIVE: Compared with matched healthy controls, quantitative sensory testing in adults with pain and sickle cell disease (SCD) demonstrates higher prevalence of sensitization, including central sensitization. The findings of allodynia and hyperalgesia may indicate neuropathic pain and could contribute to a paradigm shift in assessment and treatment of SCD pain.

Supporting Asian patients with metastatic breast cancer during ixabepilone therapy.

IMPORTANCE OF THE FIELD: Ixabepilone is currently FDA-approved in metastatic breast cancer, and most patients in the registrational trials were Caucasian. Studies in Asian populations receiving other cytotoxic agents have revealed differential pharmacokinetics and clinical outcomes. As such, clinicians should understand the possible contributions of Asian ethnicity and culture to the clinical profile of ixabepilone. AREAS COVERED IN THIS REVIEW: Studies in Asian patients receiving other chemotherapeutics reported altered toxicity profiles for myelosuppression, neurotoxicity and gastrointestinal symptoms. Encouragingly, the limited clinical data in Asian patients receiving ixabepilone suggest that efficacy and toxicity in these women resemble those reported in the ixabepilone registrational trials. WHAT THE READER WILL GAIN: The reader will better understand how Asian genetics and culture may influence treatment outcomes and patient attitudes toward therapy and interaction with caregivers. Management of ixabepilone-related adverse events is also discussed with an emphasis on special considerations for Asian patients. TAKE HOME MESSAGE: Awareness of possible altered drug response in Asian patients will aid clinicians in monitoring for toxicity, recognizing the need for dose modification and educating patients. Sensitivity to cultural aspects that are unique to Asians may improve adherence, reporting of adverse events and trust among Asian patients receiving ixabepilone.