Pharmacological and non-pharmacological treatments for neuropathic pain: Systematic review and French recommendations

International audienceTo investigate the physiopathology of pain in chronic inflammatory rheumatic diseases (CIRDs), we assessed the prevalence of migraine and neuropathic pain in 499 patients with CIRDs. We studied 238 patients with rheumatoid arthritis, 188 with spondyloarthritis (SpA), 72 with psoriatic arthritis (PsA), and 1 unclassified. Migraine was diagnosed according to IHS migraine diagnostic criteria. Neuropathic pain was diagnosed when patients scored at least 3 on the DN4 questionnaire. Participants completed a validated self-assessment questionnaire. Migraine prevalence was 34% (165/484), and it was highest in PsA. Risk factors for migraine were a high level of anxiety, female sex, young age, and TNF-alpha inhibitor treatment (OR = 1.90 (1.13–3.25)). Besides, high disease activity was a risk factor in SpA. Blood CRP level was not significantly associated with migraine. Of 493 patients with CIRDs, 21.5% had chronic pain with neuropathic characteristics. Compared to the French general population, these patients had significantly higher prevalences of migraine (two-fold) and neuropathic pain (three-fold). This study showed that migraine and neuropathic pain frequently occurred in patients with rheumatic diseases. Therefore, upon reporting residual pain, these patients should be checked for the presence of migraine or neuropathic pain, despite adequate clinical control of rheumatic disease

Efficacy and safety of a T-type calcium channel blocker in patients with neuropathic pain: A proof-of-concept, randomized, double-blind and controlled trial

International audienceBackgroundT‐type calcium channels have been shown to play an important role in the initiation and maintenance of neuropathic pain and represent a promising therapeutic target for new analgesic treatments. Ethosuximide (ETX), an anticonvulsant and a T‐type channel blocker has shown analgesic effect in several chronic pain models but has not yet been evaluated in patients with neuropathic pain.MethodsThis proof‐of‐concept, multicentre, double‐blind, controlled and randomized trial compared the efficacy and safety of ETX (given as add‐on therapy) to an inactive control (IC) in 114 patients with non‐diabetic peripheral neuropathic pain. After a 7‐day run‐in period, eligible patients aged over 18 years were randomly assigned (1:1) to ETX or IC for 6 weeks. The primary outcome was the difference between groups in the pain intensity (% of change from the baseline to end of treatment) assessed in the intention‐to‐treat population. This study is registered with EudraCT (2013‐004801‐26) and ClinicalTrials.gov (NCT02100046).ResultsThe study was stopped during the interim analysis due to the high number of adverse events in the active treatment group. ETX failed to reduce total pain and showed a poor tolerance in comparison to IC. In the per‐protocol analysis, ETX significantly reduced pain intensity by 15.6% (95% CI −25.8; −5.4) from baseline compared to IC (−7.8%, 95% CI −14.3; −1.3; p = 0.033), but this result must be interpreted with caution because of a small subgroup of patients.ConclusionEthosuximide did not reduce the severity of neuropathic pain and induces, at the doses used, many adverse events.SignificanceThis article shows that ETX is not effective to treat neuropathic pain. Nevertheless, per‐protocol analysis suggests a possible analgesic effect of ETX. Thus, our work adds significant knowledge to preclinical and clinical data on the benefits of T‐type calcium channel inhibition for the treatment of neuropathic pain

Infections and multiple sclerosis: Recommendations from the French Multiple Sclerosis Society

International audienceIntroduction: Viral, bacterial, or fungal infections are suspected of triggering multiple sclerosis (MS) and promoting relapses of the disease and are likely to be promoted by immune-active treatments. This raises questions about the infectious workup and preventive treatment of these infections prior to their initiation.Objectives: To establish recommendations on infections and MS. Provide information to patients and healthcare professionals on the minimal infectious workup to be performed in an MS patient at diagnosis and prior to initiation of immuno-active therapy in MS.Methods: The recommendation attempts to answer four main questions about infections and MS. The French Group for Recommendations in Multiple Sclerosis (France4MS) did a systematic review of articles from PubMed and universities databases (from January 1975 to June 2020), using the RAND/UCLA formalized consensus method. The RAND/UCLA method has been developed to synthesize the scientific literature and expert opinions on health care topics and was used for reaching a formal agreement. Twenty-three experts contributed to the detailed review and a group of 63 multidisciplinary health professionals validated the final version of 36 recommendations.Results: It is recommended that MS patients undergo a minimal infectious workup, check their vaccination status at diagnosis, and repeat it during follow-up and before starting immunotherapy. Screening and preventive treatment of viral (group Herpes virus, HPV, JCV, HCV, HBV), bacterial (mycobacteria) and fungal (Cryptococcus) infections is recommended prior to the initiation of certain immuno-active MS therapies.Discussion and conclusions: At diagnosis of MS and prior to the choice of therapeutic strategy, it is recommended to update the vaccination schedule of MS patients in reference to the HCSP vaccination schedule and the SFSEP recommendations. Before starting immunosuppressive treatment, it is recommended to inform patients of the risks of infections and to look for a constitutive or acquired immune deficiency. Health professionals and patients should be informed of the updated recommendations on infections and MS