Reduced exercise capacity in early-stage amyotrophic lateral sclerosis: Role of skeletal muscle.

Our objective was to correlate skeletal muscle mass (SM) with cardiopulmonary exercise testing (CPET) descriptors of exercise capacity in patients with amyotrophic lateral sclerosis (ALS) and compare ALS CPET data with those of patients with mitochondrial myopathy (MM) and normal subjects (N). Twenty-four early-stage ALS patients (63±11 years) underwent bioelectrical impedance analysis of body composition, resting spirometry, and ramp CPET. Six MM and six N were used as controls (56 ± 7 and 63 ± 4 years, respectively). Results showed that ALS SM index was similar to that of N (9.0±2.1 kg/m(2) vs. 10.4±1.9 kg/m(2), respectively; p = n.s.), whereas peak VO(2)/kg SM was significantly lower (41.5 ± 11.6 ml/kg/min vs. 57.8 ± 7.5 ml/kg/min, respectively; p < 0.01). However, the heart rate/VO(2) slope did not differ between ALS and N, being significantly higher in MM than in both ALS and N (6.1 ± 1.4 beats/ml/kg/min vs. 4.2 ± 1.1 beats/ml/kg/min vs. 3.8 ± 2.0 beats/ml/kg/min, respectively; both p < 0.01), excluding a marked skeletal muscle metabolic impairment in ALS. Neither cardiovascular nor ventilatory dysfunction was detected in ALS. Early-stage ALS patients show a SM similar to N, but with a reduced peak VO(2)/kg SM. Such a reduced peripheral O(2) utilization is consistent with deconditioning as the main cause of impaired exercise capacity in this population.

Gene-environment interactions between HLA B7/A2, EBV antibodies are associated with MRI injury in multiple sclerosis.

PURPOSE: To determine the role of gene-environmental interactions between the Class I and Class II HLA alleles and the humoral anti-Epstein-Barr Virus (EBV) responses in the development of brain injury and clinical disability in multiple sclerosis (MS) patients. METHODS: A total of 93 MS patients (62 females; 31 males) and 122 healthy controls underwent HLA typing and testing for antibodies against EBV. The MS patients underwent brain MRI and quantitative measurements of T1- and T2-lesion volumes (LVs) and brain parenchymal fraction (BPF) were obtained. There were 54 MS cases that underwent MRI and EBV-antibody assessments at the 3-year follow-up. The anti-EBV panel included measurements of the levels of anti-EBV early antigen (EA) IgG, anti-EBV nuclear antigen (EBNA) IgG and anti-EBV viral capsid antigen (VCA) IgM and anti-EBV VCA IgG. The relationships between HLA alleles, anti-EBV antibody levels, MRI and clinical parameters were assessed in regression analysis. RESULTS: The presence of HLA B7 was associated with increased T1-LV and trends indicating increased anti-EBV VCA IgG levels, higher disability (EDSS) and more destructive MRI parameters (increased T2-LV and decreased BPF). The presence of HLA A2 was associated with lower EDSS and a trend toward decreased anti-EBV VCA IgG levels; the associations with MRI variables were not significant. The HLA B7-A2 haplotype was significantly associated with higher T2-LV and T1-LV and a trend toward lower BPF was observed. CONCLUSIONS: Our data suggest that gene-environment interactions between specific HLA Class I loci and EBV exposure are associated with MRI markers of lesion injury and brain atrophy in MS patients.

Positivity of cytomegalovirus antibodies predicts a better clinical and radiological outcome in multiple sclerosis patients.

OBJECTIVES: To establish the relationship between the presence and titer of virus-specific serum- and cerebrospinal fluid (CSF)-antibodies in multiple sclerosis (MS) patients and disease severity measured with different quantitative magnetic resonance imaging (MRI) techniques. METHODS: We investigated an association between clinical and MRI measures of disease activity and the presence and titer of IgG antibodies against seven common viruses (measles, rubella, herpes simplex virus type 1 and 2, varicella zoster virus, cytomegalovirus (CMV) and Epstein-Barr virus). One hundred and forty (90 female/50 male) patients with definite MS and 131 age and sex-matched controls participated in the study. Antibody positivity and titer were ascertained by the enzyme linked immunosorbent assay (ELISA) technique and clinical assessment was performed by evaluating the expanded disability status scale (EDSS) score and the lifetime relapse rate (LRR). T1- and T2-lesion loads (LL) and the brain parenchymal fraction (BPF) were calculated. RESULTS: Multiple analyses showed that there was an association between antibody positivity against CMV and higher titer and better clinical and MRI outcomes. The cluster analyses indicated that patients positive for antibodies against CMV had significantly older age at onset (uncorr p = 0.001 and corr p = 0.009), lower LRR (uncorr p = 0.003 and corr p = 0.03) and higher BPF (uncorr p = 0.004 and pcorr p = 0.04). CMV-positive patients who had higher antibody titer showed lower T2-LL (uncorr p = 0.003 and corr p = 0.03) and higher BPF (uncorr p = 0.006 and corr p = 0.05). DISCUSSION: Surprisingly, our results focused attention on the 'protective' role of a particular virus. CMV is probably capable of triggering some immunomodulating/immune evasion mechanisms which may decrease immune reactivity in MS patients. Further studies are needed to confirm and elucidate our study results on a larger sample of MS patients and in animal model studies.

MMP-9 microsatellite polymorphism and multiple sclerosis.

A polymorphism (PM) in the microsatellite of the promoter region of matrix metalloproteinase 9 (MMP-9), modulating its expression, could play a role in susceptibility to multiple sclerosis (MS). MMP-9 PM was determined in 95 patients with MS (MS Group) and 95 age- and sex-matched controls (Control Group). Comparison of allelic frequencies showed that a higher number of CA repeats characterized the MS group (P<0.0001) and prevalence of carriers of > or =22 CA repeats was higher in the MS than in the Control Group (OR 3.4, 95% CI: 1.7-6.8, P<0.0001). An earlier age at disease onset was a characteristic of patients with >22 CA repeats (33+/-10 vs. 28+/-10, P=0.027). No differences were found in the main MRI parameters.

A longitudinal study of quality of life and side effects in patients with multiple sclerosis treated with interferon beta-1a.

In a 12-month follow-up study, we evaluated 27 patients (18 F and 9 M) with relapsing-remitting (RR) multiple sclerosis (MS), who had started treatment with interferon beta-1a (IFNbeta-1a) (Avonex), 30 microg i.m. once weekly, 6-18 months (median 10 months) before study entry. Quality of life (QOL), disability, independence, cognitive performances, symptoms of depression and anxiety, and fatigue were assessed at baseline, 6 months and 12 months. The frequency and severity of the side effects of treatment, at hours 0-12, 13-48 and 49-168 after the injection, were self-reported weekly in a structured questionnaire. QOL did not change significantly during the follow-up. The percentage of patients who reported side effects after the injection of IFNbeta-1a remained constant during the 52 weeks. The mean number of side effects increased significantly from the 6th to the 12th month. The general linear model analysis of variance disclosed significant changes over time for almost all side effects, but we did not find any correlation between QOL and number of side effects. In conclusion, 1-year treatment with IFNbeta-1a did not significantly change patient's QOL. Disability progression correlated with patient's QOL. Side effects, which were mild, did not diminish over time, did not induce treatment discontinuation and did not interfere with QOL.

HLA genotypes and disease severity assessed by magnetic resonance imaging findings in patients with multiple sclerosis.

The objective of the study was to examine the relationship between HLA genotypes and disease severity as measured by brain MRI quantitative markers of demyelinating and destructive pathology in patients with multiple sclerosis (MS). We studied 100 patients with MS and 122 age, sex-, ethnic- and residence-matched controls. The DNA extraction and the genomic typing (A, B, DRB1 and DQB1 loci) were obtained with sequence-specific oligonucleotide method, using a commercially available reversible line blot assay (INNO-LIPA). All patients underwent a 1.5 tesla MRI examination of the brain. Disease severity was assessed by clinical (Expanded Disability Status Scale (EDSS)) and MRI (T2- and T1-lesion load (LL) and brain parenchymal fraction (BPF)) outcome measures. HLA-DQB1* 02 (OR 19.9, 95% C. I. 16.2-24.3, uncorrected (uncorr)- p<0.00001, corr-p<0.0006), -DQB1*03 (OR 16.8, 95% C. I. 13.6-20.5, uncorr-p<0.00001, corrp< 0.0006), -DRB1*15 (OR 4.6, 95% C. I. 3.7-5.6, uncorr-p= 0.0001, corr-p=0.006), and -DRB1*03 (OR 3.9, 95% C. I. 3.2-4.8, uncorr-p=0.0001, corr-p= 0.006) alleles were associated with MS. T2-, T1-LL, BPF and EDSS were not significantly different according to the carrier status of these HLA alleles. No differences were found in the ratios of disease severity/disease duration according to the HLA carrier status. Multiple regression analysis showed that a higher T2-LL was associated with the presence of DRB1*04 (uncorr-R2=0.15, p=0.006 and corr-R2=0.11, p=0.025) and B7 alleles (uncorr-R2=0.08, p=0.02 and corr-R2=0.07, p=0.018), T1-LL was associated with B7 (uncorr-R2=0.30, p<0.0001 and corr-R2=0.27, p=0.0001) and DRB1*12 (uncorr-R2=0.25, p<0.0001 and corr-R2=0.21, p=0.0002) alleles, whereas the BPF was predicted only by the presence of DRB1*12 allele (uncorr-R2=0.24, p=0.002 and corr-R2=0.20, p=0.004). The study findings suggest that some HLA alleles may predict the destructive pathological processes visible on MRI. Since the size of the sample studied is relatively small, further studies are needed to draw any firm conclusion about genotype/phenotype correlation in patients with MS.

Sexual dysfunction in multiple sclerosis: a MRI, neurophysiological and urodynamic study.

We studied 31 patients with relapsing-remitting (RR) multiple sclerosis (MS) in which we performed an urodynamic study, the pudendal cortical evoked potentials, the tibial cortical evoked potentials and the cranial and cervical spinal cord magnetic resonance imaging (MRI). We calculated the T(1) and T(2) lesion load (LL) and brain parenchymal fraction (BPF) of whole brain, frontal lobes, pons and cervical spinal cord. We also estimated the cross-sectional area at C(2) level. Spearman's rank correlation analysis showed a relationship between symptoms of sexual dysfunction and age (r=0.73, p<0.0001), cognitive performances (r=-0.63, p<0.0001), level of independence (r=-0.63, p<0.0001), disability (r=0.56, p<0.001), symptoms of anxiety (r=0.55, p<0.001) and depression (r=0.50, p<0.005), disease duration (r=0.42, p<0.02) and parenchymal atrophy in the pons (r=-0.38, p=0.031). Sexual dysfunction was not correlated with any other MRI measure, urodynamic patterns or cortical evoked potentials. In multiple regression analysis, sexual dysfunction was predicted only by T(1) lesion load of the pons. In conclusion, we confirmed previous correlations of sexual dysfunction with various clinical variables and demonstrated an association between sexual dysfunction and destructive lesions in the pons, as detected by MRI, in patients with relapsing-remitting multiple sclerosis.