Humoral Response to SARS-COV-2 Vaccination in Patients with Multiple Sclerosis and Neuromyelitis Optica Spectrum Disorder: A Real-World Study.

INTRODUCTION: The risk of SARS-CoV-2 infection or severe coronavirus disease 2019 (COVID-19) has been shown to increase in patients with multiple sclerosis (MS). Vaccination is recommended in this patient population, and the effect of disease-modifying treatments (DMTs) on response to vaccination should be considered. METHODS: This prospective, observational, cross-sectional study investigated humoral response after COVID-19 vaccination as well as possible predictors for response in patients with MS and other neuroinflammatory diseases who received DMTs in routine clinical practice in Spain. Responses were compared versus those seen in healthy controls. RESULTS: After vaccination against COVID-19, most patients with MS developed an immune response comparable to that of healthy individuals. However, approximately half of patients receiving a sphingosine-1-phosphate modulator (SP1-M, fingolimod or siponimod) or a B-cell-depleting agent (aCD20, ocrelizumab or rituximab) did not develop protective antibodies, although patients receiving other DMTs had humoral immune responses comparable to healthy controls. Lymphocyte count was not associated with reduced humoral response in patients receiving an SP1-M or aCD20, whereas, in patients receiving an aCD20 or SP1-M, older age was associated with lower anti-SARS-CoV-2 spike protein immunoglobulin G antibody levels. CONCLUSIONS: Treatment with aCD20 or SP1-M therapies appears to be associated with a lower humoral response to vaccines against SARS-CoV-2. Vaccination prior to initiation of these DMTs should be recommended whenever possible.

Vitamin D receptor and binding protein genes variants in patients with migraine.

BACKGROUND/OBJECTIVES: Several studies have shown a relationship between vitamin D and migraine, including the association between decreased serum 25-hydroxyvitamin D in patients with migraine and the positive effects of vitamin D supplementations in the therapy of this disease. Two single-nucleotide variants (SNVs) vitamin D receptor (VDR) gene, VDR rs2228570, and VDR rs731236 have shown an association with migraine risk in a previous case-control association study, while an exome sequencing study identified a rare variant in GC vitamin D binding protein gene. This study aims to look for the association between several common variants in these two genes and the risk for migraine. METHODS: We genotyped 290 patients diagnosed with migraine and 300 age-matched controls using specific TaqMan assays for VDR rs2228570, VDR rs731236, VDR rs7975232, VDR rs739837, VDR rs78783628, GC rs7041, and GC rs4588 SNVs. RESULTS: We did not find an association between these SNVs and the risk for migraine. None of these SNVs were related to the positivity of a family history of migraine or with the presence of aura. The VDR rs731236A allele showed a significant association with the triggering of migraine attacks by ethanol (Pc = 0.007). CONCLUSIONS: In summary, the results of the current study suggest a lack of association between common SNVs in the VDR and GC gene and the risk of developing migraine. The possible relationship between VDR rs731236 and the triggering of migraine episodes with ethanol deserves future studies.

Lack of Association between Common LAG3/CD4 Variants and Risk of Migraine.

Several papers have been published suggesting a probable role of inflammatory factors in the etiopathogenesis of migraine. In this study, we investigated the possible association between common variants in the LAG3/CD4 genes (both genes, which are closely related, encode proteins involved in inflammatory and autoimmune responses) in the risk of migraine in a cohort of Caucasian Spanish participants. For this purpose, the frequencies of CD4 rs1922452, CD4 rs951818, and LAG3 rs870849 genotypes and allelic variants, using a specific TaqMan-based qPCR assay, were assessed in 290 patients diagnosed with migraine and in 300 healthy controls. The relationship of these variables with several clinical features of migraine was also analyzed. The frequencies of the analyzed LAG3/CD4 genotypes did not differ significantly between the two study groups and were not related to the sex, age at onset of migraine, family history of migraine, presence or absence of aura, or the triggering effect of ethanol on migraine episodes. These results suggest a lack of association between common variants in the LAG3/CD4 genes and the risk of developing migraine in the Caucasian Spanish population.

LAG3/CD4 Genes Variants and the Risk for Restless Legs Syndrome.

According to several studies, inflammatory factors could be related to the pathogenesis of idiopathic restless legs syndrome (RLS). In addition, RLS and Parkinson's disease (PD) have shown a possible relationship, and recent studies have shown an association between CD4 rs1922452 and CD4 rs951818 single nucleotide variants (SNVs) and the risk for PD. For these reasons, we investigated the possible association between common variants in the LAG3/CD4 genes (which encoded proteins involved in inflammatory and autoimmune responses) and the risk for RLS in a Caucasian Spanish population. We assessed the frequencies of CD4 rs1922452, CD4 rs951818, and LAG3 rs870849 genotypes and allelic variants in 285 patients with idiopathic RLS and 350 healthy controls using a specific TaqMan-based qPCR assay. We also analyzed the possible influence of the genotypes' frequencies on several variables, including age at onset of RLS, gender, family history of RLS, and response to drugs commonly used in the treatment of RLS. We found a lack of association between the frequencies of genotypes and allelic variants of the 3 SNVs studied and the risk of RLS, and a weak though significant association between the CD4 rs1922452 GG genotype and an older age at onset of RLS. With the exception of this association, our findings suggest that common SNVs in the CD4/LAG3 genes are not associated with the risk of developing idiopathic RLS in Caucasian Spanish people.

Association between LAG3/CD4 Genes Variants and Risk for Multiple Sclerosis.

Several recent works have raised the possibility of the contribution of the lymphocyte activation gene 3 (LAG3) protein in the inflammatory processes of multiple sclerosis (MS). Results of studies on the possible association between LAG3 gene variants and the risk of MS have been inconclusive. In this study, we tried to show the possible association between the most common single nucleotide variants (SNVs) in the CD4 and LAG3 genes (these two genes are closely related) and the risk of MS in the Caucasian Spanish population. We studied the genotypes and allelic variants CD4 rs1922452, CD4 rs951818, and LAG3 rs870849 in 300 patients diagnosed with MS and 400 healthy patients using specific TaqMan-based qPCR assays. We analyzed the possible influence of the genotype frequency on age at the onset of MS, the severity of MS, clinical evolutive subtypes of MS, and the HLADRB1*1501 genotype. The frequencies of the CD4 rs1922452, CD4 rs951818, and LAG3 rs870849 genotypes and allelic variants were not associated with the risk of MS and were unrelated to gender, age at onset and severity of MS, the clinical subtype of MS, and HLADRB1*1501 genotype. The results of the current study showed a lack of association between the CD4 rs1922452, CD4 rs951818, and LAG3 rs870849 SNVs and the risk of developing MS in the Caucasian Spanish population.

Treatment with natalizumab during pregnancy in multiple sclerosis: The experience of implementing a clinical practice protocol (NAP-30).

BACKGROUND: Pregnancy planning in women with highly active multiple sclerosis (HAMS) who need a high-efficacy disease-modifying therapy (heDMT) currently requires a careful risk-benefit evaluation. This includes minimizing fetal drug toxicity and preventing MS reactivation. We describe our experience with natalizumab in women with HAMS and unplanned pregnancy by implementing a clinical practice protocol (NAP-30) designed to maintain the effectiveness of natalizumab during pregnancy, reduce fetal exposure and prevent complications. METHODS: This was an observational retrospective study including women with HAMS on active treatment with natalizumab who became unexpectedly pregnant in the period 2018-2021 and continued this treatment during pregnancy according to the NAP-30 protocol. MS clinical and radiological variables were analyzed before and during pregnancy and in the postpartum period, along with maternal and fetal toxicity during pregnancy and safety findings in newborns. We also describe the NAP-30 protocol, which includes the use of a bridging dose to adjust and maintain natalizumab infusions every 6 weeks during pregnancy up to week 30 and scheduled delivery at week 40. RESULTS: Six women (one in her first gestation) with a median age of 31.5 years at the onset of pregnancy (min-max: 24-37 years) were included. All were negative for anti-John Cunningham virus (JCV) antibodies and were on treatment with intravenous natalizumab 300 mg every 4 weeks. At the time of conception, three patients had received 12, 17 and 53 infusions of natalizumab, respectively, while for the remaining three patients natalizumab was their first DMT (two patients had received 6 infusions and one patient had received 3 infusions of natalizumab). All six patients received 6 doses of natalizumab during pregnancy according to the NAP-30 protocol. After delivery, all six patients restarted natalizumab every 4 weeks (median: 3 days; range: 2-4 days). No patients had relapses during pregnancy or at 6 months postpartum, nor did they develop any general health or laboratory abnormalities. The MRI scan performed at 4-6 months postpartum showed no new T2 lesions or gadolinium-enhancing lesions. No miscarriages or threatened miscarriages were reported. One of the patients underwent elective preterm delivery at week 35 after mild-to-moderate anemia was detected by fetal Doppler scan. The newborn had low birth weight (2080 g) and mild anemia, which resolved within two months with oral iron supplementation. The other infants were born with normal birth weight and showed no blood count abnormalities. After a median follow-up of 10 months, all six babies showed normal development with no complications detected. CONCLUSIONS: Based on our experience, the implementation of the NAP-30 protocol in women with HAMS and unplanned pregnancy undergoing treatment with natalizumab allows the continuation of natalizumab during pregnancy, with a very favorable clinical and radiological effectiveness and maternal-fetal safety profile during pregnancy and postpartum. Both in pregnancy with HAMS and in general, and particularly for successful implementation of the NAP-30 protocol, obstetric support and monitoring is essential for adequate pregnancy management.

Increased serum diamine oxidase activity in nonallergic patients with migraine.

BACKGROUND/OBJECTIVES: Histamine has shown a possible role in the etiopathogenesis of migraine. It has been reported an association between some polymorphisms in the diamine oxidase (DAO) gene and migraine, especially in women. Two studies addressing DAO activity in migraine patients showed conflicting results. We investigated the possible relationship of serum DAO activity and histamine levels and 3 polymorphisms in the DAO gene with the risk for migraine. METHODS: We studied the frequencies of DAO rs10156191, rs1049742 and rs1049793 genotypes and allelic variants in 298 migraine patients and 360 healthy controls (using a TaqMan-based qPCR assay), and serum DAO activity and histamine levels in a subset of 99 migraine patients and 115 controls with strict exclusion criteria, and analysed the relationship of these variables with several clinical features of migraine. RESULTS: The frequencies of the DAO genotypes and allelic variants analysed were similar in migraine patients and controls. Serum DAO activity was significantly higher in migraine patients (Vmax/Km 4.24 ± 2.93 vs. 3.60 ± 7.64, p < 0.001), especially in females (Vmax/Km 4.63 ± 2.96 vs. 3.18 ± 2.32, p < 0.0001), while serum histamine was similar in both study groups. CONCLUSION: Serum DAO activity was increased in patients with migraine, especially in females, while serum histamine levels were normal. None of the studied polymorphisms was associated with the risk for migraine.

Serum Trace Elements Concentrations in Patients with Restless Legs Syndrome.

Increased brain and serum zinc levels in patients with idiopathic restless legs syndrome (idiopathic RLS or iRLS) were described when compared with controls, suggesting a possible role of zinc in the pathogenesis of this disease. However, serum magnesium, calcium, manganese, iron, and copper levels of RLS patients were similar to controls, suggesting a specific impairment of zinc-dependent metabolism in RLS. The aim of this study is to assess the serum concentrations of trace elements involved in oxidative stress or causing peripheral nerve toxicity in a large series of patients with iRLS and controls. We determined serum levels of iron, copper, manganese, zinc, magnesium, selenium, calcium, aluminium, lead, cadmium, arsenic and mercury in 100 patients diagnosed with iRLS and in 110 age- and sex-matched controls using Inductively Coupled Plasma Mass Spectrometry. Serum copper, magnesium, selenium, and calcium concentrations were significantly higher in RLS patients than in controls. These differences were observed both in men and women. There were no major correlations between serum trace metal concentrations and age at onset of RLS or RLS severity, nor was there any association with a family history of RLS or drug response. This study shows an association between increased serum concentrations of copper, magnesium, selenium, and calcium with RLS in a Spanish Caucasian population and does not confirm the previously reported increase in serum zinc concentrations in patients suffering from this disease, suggesting that the different accuracy of the analytical methods used could have influenced the inconsistent results found in the literature.

SARS-CoV-2 Infection in Multiple Sclerosis: Results of the Spanish Neurology Society Registry.

OBJECTIVE: To understand COVID-19 characteristics in people with multiple sclerosis (MS) and identify high-risk individuals due to their immunocompromised state resulting from the use of disease-modifying treatments. METHODS: Retrospective and multicenter registry in patients with MS with suspected or confirmed COVID-19 diagnosis and available disease course (mild = ambulatory; severe = hospitalization; and critical = intensive care unit/death). Cases were analyzed for associations between MS characteristics and COVID-19 course and for identifying risk factors for a fatal outcome. RESULTS: Of the 326 patients analyzed, 120 were cases confirmed by real-time PCR, 34 by a serologic test, and 205 were suspected. Sixty-nine patients (21.3%) developed severe infection, 10 (3%) critical, and 7 (2.1%) died. Ambulatory patients were higher in relapsing MS forms, treated with injectables and oral first-line agents, whereas more severe cases were observed in patients on pulsed immunosuppressors and critical cases among patients with no therapy. Severe and critical infections were more likely to affect older males with comorbidities, with progressive MS forms, a longer disease course, and higher disability. Fifteen of 33 patients treated with rituximab were hospitalized. Four deceased patients have progressive MS, 5 were not receiving MS therapy, and 2 were treated (natalizumab and rituximab). Multivariate analysis showed age (OR 1.09, 95% CI, 1.04-1.17) as the only independent risk factor for a fatal outcome. CONCLUSIONS: This study has not demonstrated the presumed critical role of MS therapy in the course of COVID-19 but evidenced that people with MS with advanced age and disease, in progressive course, and those who are more disabled have a higher probability of severe and even fatal disease.

Common Endothelial Nitric Oxide Synthase Single Nucleotide Polymorphisms are not Related With the Risk for Restless Legs Syndrome.

Because nitric oxide and endothelial dysfunction could play a role in the pathogenesis of idiopathic restless legs syndrome (RLS), as was suggested by some preliminary data, we investigated the possible association between the rs2070744 variants in the endothelial nitric oxide synthase (eNOS or NOS3) gene (chromosome 7q36.1) and the risk for RLS in a Caucasian Spanish population. We assessed the frequencies of NOS3 single nucleotide polymorphisms (SNPs) rs2070744, rs1799983, and rs79467411 genotypes and allelic variants in 273 patients with idiopathic RLS and 325 healthy controls using a TaqMan-based qPCR assay. We also analyzed the possible influence of genotype frequency on age at onset of RLS symptoms, gender, family history of RLS, and response to drugs commonly used in the treatment of RLS such as dopaminergic drugs, clonazepam, and GABAergic drugs. The frequencies of genotypes and allelic variants were not associated with the risk for RLS and were not influenced by gender, age, and positive family history of RLS. We identified weak statistical associations of the SNP rs1799983 with the response to dopamine agonists (Pc = 0.018 for the rs1799983 G/T genotype) and of the SNP rs79467411 with the response to clonazepam (Pc = 0.018 for the rs79467411 G allele), although these findings should be cautiously interpreted and require further confirmation. These associations aside, our findings suggest that common NOS3 SNPs are not associated with the risk for idiopathic RLS in Caucasian Spanish people.

Real-world experience of ocrelizumab in multiple sclerosis in a Spanish population.

OBJECTIVE: Pivotal trial have shown that patients with multiple sclerosis (MS) receiving ocrelizumab had better outcomes. However, data on ocrelizumab in clinical practice are limited. The aim of this study was to evaluate the preliminary safety profile and effectiveness of ocrelizumab treatment for multiple sclerosis (MS) in a real-world clinical setting. METHODS: We conducted a retrospective study including consecutive patients from nine public hospitals in south-eastern Spain who received ocrelizumab after it was approved. RESULTS: A total of 228 MS patients were included (144 with relapsing-remitting MS [RRMS], 25 secondary progressive MS [SPMS], and 59 primary progressive MS [PPMS]). Median follow-up period was 12 months (range, 1-32). No evidence of disease activity (NEDA) status at year 1 was achieved in 91.2% of the relapsing MS (RMS) population, while disability progression was detected in 37.5% of the PPMS patients (median follow-up period, 19 months). The most common adverse events reported were infusion-related reactions and infections, with the most common infections being urinary tract infections followed by upper respiratory infections and COVID-19. INTERPRETATION: The preliminary results in our real-world setting show that ocrelizumab presented excellent results in suppressing disease activity with a favorable and consistent safety profile.

Serum vitamin D, vitamin D receptor and binding protein genes polymorphisms in restless legs syndrome.

BACKGROUND/OBJECTIVES: Several studies showed lower serum 25-hydroxyvitamin D levels in patients with idiopathic restless legs syndrome (RLS) compared with matched controls, and a single study showed an association between the rs731236 single nucleotide polymorphism (SNP) in the vitamin D receptor (VDR) gene and the risk for RLS. We aimed to study the relationship between the serum 25-hydroxyvitamin D levels and to confirm previous findings related to SNPs in the VDR and the GC vitamin D binding protein (GC) gene, with the risk for RLS in the Spanish Caucasian population. METHODS: We genotyped 285 idiopathic RLS patients and 325 age and sex-matched controls for VDRrs2228750, VDRrs7975232, VDRrs739837, VDRrs78783628, GCrs7041 and GCrs4588 SNPs using TaqMan assays, and determined serum 25-hydroxyvitamin D levels in 111 idiopathic RLS patients and 167 controls using an ELISA commercial kit. RESULTS: Serum 25-hydroxyvitamin D levels were significantly higher in RLS patients than in controls but were unrelated with the 7 SNPs studied. None of the 7 SNPs analyzed was associated with the risk for idiopathic RLS or with a positive family history of RLS. However, RLS patients carrying the rs7975232CC genotype or the rs7975232C allele, had a higher frequency of response to GABAergic drugs. Associations between the age at onset and the severity of RLS with SNPs were inconsistent. CONCLUSIONS: This study shows an association between increased serum concentrations of 25-hydroxyvitamin D and a lack of association between 7 SNPs in the VDR and in the GC genes with RLS in the Spanish Caucasian population.

Endothelial nitric oxide synthase (NOS3) rs2070744 polymorphism and risk for multiple sclerosis.

The possible role of oxidative stress and nitric oxide (NO) in the pathogenesis of multiple sclerosis (MS) has been suggested by several neuropathological, biochemical, and experimental data. Because the single-nucleotide polymorphism (SNP) rs2070744 in the endothelial nitric oxide synthase (eNOS or NOS3) gene (chromosome 7q36.1) showed association with the risk for MS in Iranians, we attempted to replicate the possible association between this SNP and the risk for MS in the Caucasian Spanish population. The frequencies of NOS3rs2070744 genotypes and allelic variants in 300 patients diagnosed with MS and 380 healthy controls were assessed with a TaqMan-based qPCR assay. The possible influence of the genotype frequency on age at onset of MS, the severity of MS, clinical evolutive subtypes of MS, and HLA-DRB1*1501 genotype were also analyzed. The frequencies of rs2070744 genotypes and allelic variants were not associated with the risk of developing MS and were not influenced by gender, age at onset and severity of MS, the clinical subtype of MS or the HLA-DRB1*1501 genotype. This study found a lack of association between NOS3 rs2070744 SNP and the risk for MS in Caucasian Spanish people.

Effectiveness of Fingolimod versus Natalizumab as Second-Line Therapy for Relapsing-Remitting Multiple Sclerosis in Spain: Second-Line GATE Study.

BACKGROUND: There is a lack of head-to-head studies comparing the efficacy of fingolimod (FIN) and natalizumab (NTZ) as second-line therapy for relapsing-remitting multiple sclerosis (RRMS). METHODS: Multicenter, observational study, in which, information of 388 patients randomly selected and treated with FIN or NTZ in routine clinical practice was retrospectively collected with the main objective of comparing the annualized relapse rate (ARR) over the first year, after FIN or NTZ treatment initiation. RESULTS: Mean ARR during the first year of treatment was 0.28 in FIN group and 0.12 in NTZ group (p = 0.0064); nevertheless, the difference between groups lost statistical significance when the propensity score analysis was performed. Time to disability -progression was similar in both treatment groups (12.3 ± 6.7 months in FIN, and 12.8 ± 0.1 months in NTZ; p = 0.4654). Treatment persistence after the first year of treatment was higher in patients treated with FIN (95%) than in those treated with NTZ (84%; p = 0.0014). CONCLUSIONS: After 12 months of treatment, both FIN and NTZ reduced the ARR, but ARR percent reduction was significantly higher with NTZ. Treatment persistence was higher in patients receiving FIN.

Redefining the Multiple Sclerosis Severity Score (MSSS): The effect of sex and onset phenotype.

BACKGROUND: The Multiple Sclerosis Severity Score (MSSS) is a widely used measure of the disability progression rate. However, the global MSSS may not be the best basis for comparison between all patient groups. OBJECTIVE: We evaluated sex-specific and onset phenotype-specific MSSS matrices to determine if they were more effective than the global MSSS as a basis for comparison within these subsets. METHODS: Using a large international dataset of multiple sclerosis (MS) patient records and the original MSSS algorithm, we constructed global, sex-specific and onset phenotype-specific MSSS matrices. We compared matrices using permutation analysis. RESULTS: Our final dataset included 30,203 MS cases, with 28.9% males and 6.5% progressive-onset cases. Our global MSSS matrix did not differ from previously published data (p > 0.05). The progressive-onset-specific matrix differed significantly from the relapsing-onset-specific matrix (p < 0.001), with lower MSSS attributed to cases with the same Expanded Disability Status Score (EDSS) and disease duration. When evaluated with a simulation, using an onset-specific MSSS improved statistical power in mixed cohorts. There were no significant differences by sex. CONCLUSION: The differences in the disability accrual rate between progressive- and relapsing-onset MS have a significant effect on MSSS. An onset-specific MSSS should be used when comparing the rate of disability progression among progressive-onset cases and for mixed cohorts.

Association between endothelial nitric oxide synthase (NOS3) rs2070744 and the risk for migraine.

Because nitric oxide could play an important role in the pathogenesis of migraine (suggested by experimental, neuropathological, biochemical, and pharmacological data), and a recent meta-analysis showed an association between the single-nucleotide polymorphism (SNP) rs2070744 in the endothelial nitric oxide synthase (eNOS or NOS3) gene (chromosome 7q36.1) and the risk for migraine in Caucasians, we attempted to replicate the possible association between this SNP and the and the risk for migraine in the Caucasian Spanish population. The frequencies for the NOS3 rs2070744 genotypes and allelic variants were assessed in 283 migraine patients and 287 healthy controls with a TaqMan-based qPCR Assay. The putative influence on genotype frequency of age at onset of migraine attacks, gender, family history of migraine, absence or presence of aura, and triggering of migraine attacks by ethanol, were also analyzed. The frequencies of NOS3 rs2070744 genotypes and allelic variants were not associated with the risk for migraine (OR [95%] CI for the minor allele = 0.91 [0.72-1.15]) and were not influenced by age at onset of migraine, gender, presence of aura, or triggering of migraine attacks by ethanol. NOS3 rs2070744CC genotypes were significantly more frequent in patients with a family history of migraine. NOS3 rs2070744 SNP is not associated with the risk for migraine in Caucasian Spanish people although it might be related to family history.

Gamma-aminobutyric acid (GABA) receptors genes polymorphisms and risk for restless legs syndrome.

The possible role of gammaaminobutyric acid (GABA) in the pathophysiology of restless legs syndrome (RLS) is suggested by the symptomatic improvement achieved with GABAergic drugs. Thalamic GABA levels have shown positive correlation with periodic limb movements indices and with RLS severity. We tried to investigate the possible association between the most common single nucleotide polymorphisms (SNPs) in the GABA receptors (GABR) genes rho1, 2, and 3 (GABRR1, GABRR2, GABRR3), alpha4 (GABRA4), epsilon (GABRE), and theta (GABRQ) with the risk of developing RLS. We studied the genotype and allelic variant frequencies of the most common SNPs in the GABRR1(rs12200969, rs1186902), GABRR2(rs282129), GABRR3(rs832032), GABRA4(rs2229940), GABRE(rs1139916), and GABRQ(rs3810651) genes in 205 RLS patients and 230 age- and gender-matched healthy controls using specific TaqMan assays. The frequencies of the GABRR3 rs832032TT genotype and the allelic variant GABRR3 rs832032T were significantly higher in RLS patients than in controls (odds ratio [95% confidence intervals] 7.08[1.48-46.44] and 1.66[1.16-2.37], respectively), although only the higher frequency of the rs832032T allele remained as significant after multiple comparison analysis, both in the whole series and in the female gender. The frequencies of the other genotypes of allelic variants did not differ significantly between RLS patients and controls. RLS patients carrying the GABRA4 rs2229940TT genotype showed a significantly younger age at onset of RLS symptoms than those with the other two genotypes. These results suggest association between GABRR3rs832032 polymorphism and the risk for RLS, and a modifier effect of GABRA4 rs2229940 on the age of onset of RLS.

Association Between the rs1229984 Polymorphism in the Alcohol Dehydrogenase 1B Gene and Risk for Restless Legs Syndrome.

Background/Objectives: Several studies have raised the possibility of an association between alcohol consumption and the risk of developing restless legs syndrome (RLS). Moreover, an important percentage of patients under alcohol detoxification therapy develop RLS symptoms that fulfil the criteria for idiopathic RLS during alcohol withdrawal. We have aimed to establish the possible association between two common single nucleotide polymorphisms (SNPs) in the alcohol-dehydrogenase 1B (ADH1B) gene and the risk for RLS. Methods: We studied, using specific TaqMan assays, the genotype and allelic variant frequencies of ADH1B rs1229984 and ADH1B rs6413413 SNPs in 205 RLS patients and 505 gender-matched healthy controls. Results: The sum of the frequencies of rs1229984CT and rs1229984TT genotypes, as well as the frequency of the rs1229984T allelic variant, was significantly higher in RLS patients than in controls, both in the whole group and in females. The frequencies of genotypes and allelic variants of the rs6413413 SNP were similar between the two groups. RLS patients with the rs1229984CT genotype were younger, and those with the rs122984TT genotype older, at onset of RLS symptoms than those with the rs1229984CC genotype. None of the studied SNPs were related either with positivity of family history for RLS or with RLS severity. Conclusions: These results suggest an association between rs1229984 SNP and the risk for RLS.

Observational Study of Switching from Natalizumab to Immunomodulatory Drugs.

OBJECTIVE: To determine the effect of disease-modifying drugs (DMDs) on disease activity rebound in patients discontinuing natalizumab (NTZ). METHODS: Twenty-one patients with relapsing-remitting multiple sclerosis (RRMS) treated with NTZ for ≥1 year and who switched to DMDs (glatiramer acetate [GA] or interferon) were followed up for 12 months in clinical practice. Clinical outcomes after NTZ cessation were assessed every 3 months for 1 year and MRI was performed at 12 months. RESULTS: Twelve months after switching from NTZ to DMDs, there were no significant differences in the annualized relapse rate (ARR) compared to the days that NTZ was used (0.3 vs. 0.1; p = 0.083); and the ARR never reached similar values to those prior to NTZ use (1.61; p < 0.001). The percentage of relapse-free patients after switching from NTZ was 71.4%. These patients did not have lower disease activity before NTZ compared with those with clinical relapses (1.3 vs. 1.7; p = 0.302), but they had lower Expanded Disability Status Scale scores (3.4 vs. 5.7; p = 0.001). DMDs had beneficial effects on MRI parameters, as 10 of 16 patients (62.5%) presented no evidence of radiological activity 12 months after NTZ discontinuation. CONCLUSIONS: Patients with RRMS and moderate disability who discontinued NTZ for safety reasons may benefit from the DMDs GA and interferon with no known risk for progressive multifocal leukoencephalopathy.