The defecation reflex in rats: fundamental properties and the reflex center

While pharmacological and physiological studies in rats are now increasing, physiological properties of their defecation have been scarcely investigated. This study was performed to define the properties of defecation in decerebrate rats, with special reference to the pontine defecation reflex center, which has been postulated in dogs. Intraluminal pressure was recorded from the colon and rectum with balloon-pressure transducer method using balloons of 15-20 mm in length and 0.1-0.3 ml in volume. Distention of a balloon in the descending colon and rectum with an additional injection of 0.03-0.1 ml air induced propulsive contractions on the descending colon and rectum. The mean of threshold pressures to induce propulsive contraction was 17.0 +/- 5.8 mm Hg (mean+/-S.E.) in the proximal part and 18.3 +/- 3.3 mm Hg in the distal part of the descending colon, and 11.8 +/- 1.3 mm Hg in the rectum. The maximum amplitude of propulsive contractions was 55 mm Hg in the rectum, 47 mm Hg in the distal part of the descending colon and 38 mm Hg in the proximal part. Similar colorectal propulsive contractions were produced by gastric distention (5-10 ml, 20-30 mm Hg) and electrical stimulation of the anal canal. Contrarily, spontaneous contractions of the proximal colon were suppressed by rectal distention and anal-canal stimulation. These results suggest that the descending colon and rectum, but not the proximal colon, were innervated by the pelvic afferent and efferent fibers mediating the defecation reflex. Pontine transection at the cerebellar peduncle level abolished colorectal propulsive contractions induced by distention of the stomach, descending colon and rectum, and stimulation of the anal canal, although much smaller contractions were still induced after the pontine transection. These results suggest that the pontine defecation reflex center exists and works in rats, as in dogs.     

Anorectal function in multiple system atrophy and Parkinson's disease.

This study was designed to investigate anorectal function in Parkinson's disease and multiple system atrophy (MSA). After a standardized interview, 17 patients with Parkinson's disease (PD) and 16 patients with multiple system atrophy (MSA) underwent anorectal manometry with a continuously perfused multi-lumen catheter, located to record pressures from the anal canal, and a balloon for rectal distension. Data were analyzed by observers blind to the neurologic diagnosis. Disease duration was shorter in the MSA than in the PD group (6+/-4 versus 10+/-5 yrs, p<0.05). Most patients reported a bowel frequency of less than three evacuations per week and some patients had fecal incontinence. Most manometric recordings disclosed an abnormal pattern during straining (a paradoxic contraction or lack of inhibition) in 13 patients with MSA and 11 patients with PD. Mean anal pressures and rectal sensitivity threshold were not significantly higher in the MSA group, whereas the inhibitory anal reflex and rectal compliance thresholds were within the normal range in both groups. Manometric patterns did not differentiate patients with MSA from patients with PD. Most patients in both groups showed an abnormal straining pattern, decreased anal tone, or both dysfunctions. In conclusion, our findings suggest that although bowel and anorectal dysfunctions do not differentiate MSA from PD, both abnormalities occur earlier and develop faster in MSA than in PD.     

Anorectal dysfunction in multiple sclerosis

OBJECTIVE: To ascertain the prevalence of anorectal dysfunction (ARD) in patients with multiple sclerosis (MS) and its relationship with MS clinical characteristics. METHODS: Prospective transversal study in 193 patients with MS. All patients fulfilled a protocol that included: demographic variables, clinical characteristics of MS and the presence of ARD and urinary dysfunction (UD). RESULTS: One hundred and ninety-three patients: 66.8% women, an average age of 42.8 (12.1) years; 67.8% of patients had relapsing remitting MS, 21.2% a secondary progressive and 10.9% a primary progressive form. The average duration of MS was 10.7 (9.4) years and the EDSS 2.8 (2.3). ARD was present in 93 patients (48.2%), and UD in 50.2%. ARD associated to UD was present in 35.7% of cases. The univariate study revealed that patients with ARD were older (P <0.001), had greater disability (P <0.0001), longer disease duration (P <0.001) and a greater association with UD (P<0.0001). ARD was more frequent in progressive forms (P<0.0001). The logistic regression analysis showed that female sex (P = 0.015), EDSS (P = 0.002) and UD (P = 0.003) were independent factors related to ARD. CONCLUSION: ARD is a highly prevalent disorder in MS. Female sex, EDSS and UD are independent predictors of ARD development.     

Effects of long-term angiotensin converting enzyme inhibition on cardiovascular variability in aging rats

We studied the effects of chronic (4 weeks) angiotensin converting enzyme inhibition with captopril on arterial pressure (AP) and heart rate (HR) variability, as well as on cardiac baroreflex sensitivity (BRS), in aged (20 months) rats. Series of basal RR interval (RRi) and systolic AP (SAP) were studied by autoregressive spectral analysis with oscillations quantified in low (LF: 0.2-0.8 Hz) and high frequency (HF: 0.8-2.5 Hz). BRS was measured by linear regression between HR and MAP changes. Captopril did not affect the spectra of RRi or SAP in young rats. Aged rats presented a reduction in variance (time domain) and in LF and HF oscillations of RRi and SAP. Captopril induced, in aged rats, a decrease in absolute and normalized LF oscillations and in LF/HF ratio of RRi. Captopril also reduced the variance, without changing its LF or HF components of SAP. Reflex tachycardia was reduced in aged as compared to young rats (-1.1+/-0.2 versus -3.4+/-0.5 bpm/mm Hg) and captopril did not affect it. Reflex bradycardia was also reduced in aged rats (-0.7+/-0.5 versus -2.0+/-0.4 bpm/mm Hg), but captopril prevented this attenuation in aged rats (-2.3+/-0.3 versus -0.7+/-0.5 bpm/mm Hg). These data indicate that there is a reduction in HR and SAP variability during aging, suggesting impairment of cardiovascular autonomic control. Captopril was able to change the power of oscillatory components of RRi, suggesting a shift in cardiac sympatho/vagal balance toward parasympathetic predominance. In addition, blockage of ACE improved the reflex bradycardia, but not the reflex tachycardia in aged rats.     

Early onset multiple sclerosis: a longitudinal study

OBJECTIVE: To evaluate the clinical course of MS in individuals with onset of MS before age 16. METHODS: Patients with onset of MS before age 16 (n = 116) with complete clinical information on the clinical course from the MS Clinic at The University of British Columbia (UBC) Site Hospital computerized database (MS-COSTAR) were included in this study. The data were compared to those from the Canadian natural history study for MS clinic attendees, regardless of age at onset. RESULTS: The mean duration of observation was 19.76 +/- 0.90 years; the mean age at MS onset was 12.73 +/- 0.25 years. Only three cases (2.6%) had a primary progressive (PP) MS course. To date, 60 (53.1%) of 113 subjects have developed secondary progressive (SP) MS. The 50% probability for SPMS was reached 23 years after onset. For patients with relapsing remitting (RR) or SPMS the mean disease duration from onset to the time of confirmed Expanded Disability Status Scale (EDSS) 3.0 was 16.03 +/- 1.17 years (at mean age 28.47 +/- 1.14); mean duration from onset to the time of EDSS 6.0 was 19.39 +/- 1.43 years (at mean age 32.32 +/- 1.44). Annual relapse rate was 0.54 +/- 0.05 per year. The correlation between the number of relapses during the first year of disease and the course of the disease was also significant. CONCLUSIONS: The prevalence of early onset MS (3.6%) in our study confirms the previous findings on early onset MS. A RR course was seen in the majority of cases of early onset MS. A high frequency of relapses, early age at permanent disability, and the presence of malignant cases raise the question of possible early use of disease-modifying therapy in patients with early onset MS.     

Clinical characteristics of progressive relapsing multiple sclerosis

OBJECTIVE: Patients with progressive relapsing (PR) multiple sclerosis (MS) may accrue disability by incomplete recovery from acute exacerbations and by ongoing deterioration. In primary progressive (PP) MS, disability accumulates solely by continuous decline. Because it is the least common form of MS, there is scant information regarding the clinical characteristics of PRMS, but relapses are reportedly uncommon. The purpose of this study is to describe the clinical features of a cohort of patients with PRMS. METHODS: A retrospective chart review of 16 patients diagnosed with PRMS at two academic MS centres over a four-year period. RESULTS: Nine men and seven women had PRMS. The mean age at onset was 35.1+/-11.2 years. The most common presenting symptom was a progressive myelopathy. The mean disease duration was 10.1+/-8.5 years and the average time to first exacerbation was 4.1+/-3.7years. Patients had an average of 2.8+/-2.3 relapses with an annualized relapse rate of 0.6+/-0.8. Time to Expanded Disability Status Scale (EDSS) 6.0 was strongly associated with time to first exacerbation. Although there was no correlation between the number of relapses and time to EDSS 6.0, there was a modest inverse relation between time to EDSS 6.0 and annualized relapse rate. CONCLUSIONS: Relapses in PRMS may occur more often than previously described and disability may accumulate more rapidly in PRMS than in PPMS. We suggest differentiating between these two forms of MS.     

Disability and prognosis in multiple sclerosis: demographic and clinical variables important for the ability to walk and awarding of disability pension

OBJECTIVE: To evaluate disability and prognosis in an untreated population-based incidence cohort of multiple sclerosis (MS) patients. METHODS: The Expanded Disability Status Scale (EDSS) score was recorded in 220 MS patients. Disease progression was assessed by life table analysis with different endpoints and multivariate Cox regression analysis was performed for evaluation of prognostic factors. RESULTS: The probability of being alive after 15 years was 94.8 +/- 1.8% (s.e.), of managing without a wheelchair (EDSS < 7.0) 75.8 +/- 3.2%, of walking without walking assistance (EDSS<6.0) 60.3 +/- 3.6%, and of not being awarded a disability pension 46.0 +/- 3.7%. The probability of still having a relapsing-remitting (RR) course after 15 years was 62.0 +/- 4.1%. A RR course and long interval between the initial (onset) and second episode (> 3 years) predicted favorable outcome. There was also a trend towards favorable outcome in patients with optic neuritis, sensory symptoms and low age at onset but these factors were associated with the RR course. Motor symptoms and high age at onset indicated unfavorable outcome, but these factors were associated with the primary progressive course. CONCLUSIONS: A RR course and long inter-episode intervals in the early phase of the disease were associated with a better outcome. Other onset characteristics indicating a favorable outcome were associated with the RR course while characteristics indicating an unfavorable outcome were associated with the PP course.     

Intrathecal IgG synthesis: marker of progression in multiple sclerosis patients

OBJECTIVES: We study the power of IgG synthesis value as a marker of disease activity in multiple sclerosis (MS). MATERIAL AND METHODS: Link index was calculated in 202 MS patients. Time between first, second and third attack and progression index (PI) were compared in patient with normal (NLI) high (HL) or very high Link index (VHLI). RESULTS: Secondary progressive (SP) patients had a higher LI than relapsing-remitting (RR) and primary progressive (PP) courses (1.10 +/- 0.5 for SP vs 0.86 +/- 0.5 for RR and 0.81 +/- 0.5 for PP, P=0.01 and 0.03, respectively). Having a HLI in MS RR and SP patients has no time effect in the development of the second and third attack. PI was higher in patients with VHIL (0.67 +/- 0.7) vs patients with NLI (0.42 +/- 0.4, P=0.008) and with HLI (0.39 +/- 0.3, P=0.001). CONCLUSIONS: This study confirmed that LI is a good marker of subsequent progression of MS.     

Orthostatic tolerance, cerebral oxygenation, and blood velocity in humans with sympathetic failure

BACKGROUND AND PURPOSE: Patients with orthostatic hypotension due to sympathetic failure become symptomatic when standing, although their capability to maintain cerebral blood flow is reported to be preserved. We tested the hypothesis that in patients with sympathetic failure, orthostatic symptoms reflect reduced cerebral perfusion with insufficient oxygen supply. METHODS: This study addressed the relationship between orthostatic tolerance, mean cerebral artery blood velocity (V(mean), determined by transcranial Doppler ultrasonography), oxygenation (oxyhemoglobin [O(2)Hb], determined by near-infrared spectroscopy), and mean arterial pressure at brain level (MAP(MCA), determined by finger arterial pressure monitoring [Finapres]) in 9 patients (aged 37 to 70 years; 4 women) and their age- and sex-matched controls during 5 minutes of standing. RESULTS: Supine MAP(MCA) (108+/-14 versus 86+/-14 mm Hg) and V(mean) (84+/-21 versus 62+/-13 cm. s(-1)) were higher in the patients. After 5 minutes of standing, MAP(MCA) was lower in the patients (31+/-14 versus 72+/-14 mm Hg), as was V(mean) (51+/-8 versus 59+/-9 cm. s(-1)), with a larger reduction in O(2)Hb (-11. 6+/-4 versus -6.7+/-4.5 micromol. L(-1)). Four patients terminated standing after 1 to 3.5 minutes. In these symptomatic patients, the orthostatic fall in V(mean) was greater (45+/-6 versus 64+/-10 cm. s(-1)), and the orthostatic decrease in O(2)Hb (-12.0+/-3.3 versus -7.6+/-3.9 micromol. L(-1)) tended to be larger. The reduction in MAP(MCA) was larger after 10 seconds of standing, and MAP(MCA) was lower after 1 minute (25+/-8 versus 40+/-6 mm Hg). CONCLUSIONS: In patients with sympathetic failure, the orthostatic reduction in cerebral blood velocity and oxygenation is larger. Patients who become symptomatic within 5 minutes of standing are characterized by a pronounced orthostatic fall in blood pressure, cerebral blood velocity, and oxygenation manifest within the first 10 seconds of standing.     

Central substance P increased blood pressure, heart rate and splanchnic nerve activity in anaesthetized rats without impairment of the baroreflex regulation.

In anaesthetized rats the baroreflex was checked before and 15 min after i.c.v. administration of 10 micrograms SP. The baroreflex was checked indirectly by relating both the reflex prolongation in heart period (inter-beat-interval: IBI) and the reflex inhibition of SNA to a pharmacologically induced BP rise. After i.c.v. administration of SP (n = 10) the resting values of the BP increased significantly from 73 +/- 16 mm Hg to 86 +/- 9 mm Hg (diastolic pressure) and from 98 +/- 20 mm Hg to 113 +/- 14 mm Hg (systolic pressure) whilst in the control group (n = 14) the BP remained constant (63 +/- 9 vs 63 +/- 7 mm Hg diastolic pressure and 106 +/- 12 vs 106 +/- 9 mm Hg systolic pressure). In the experimental group the resting value in IBI was shortened significantly from 218 +/- 40 ms to 167 +/- 28 ms (controls: 218 +/- 22 ms vs 218 +/- 18 ms) and the SNA (estimated in arbitrary units) rose significantly by about 50% in relation to the reference period before i.c.v. SP (3.31 +/- 0.11 vs 6.27 +/- 0.17 arbitrary units per IBI). In contrast, the baroreflex behaved similarly before and after any treatment, i.e. both the reflex prolongation in IBI (1.34 +/- 0.75 vs 1.39 +/- 0.95 ms/mm Hg) and the reflex inhibition of SNA (0.0312 +/- 0.01 vs 0.0555 +/- 0.015 arbitrary units/mm Hg) caused by that pharmacologically induced BP rise were comparable before and after i.c.v. SP.(ABSTRACT TRUNCATED AT 250 WORDS)     

Activated suppressor cell function in severely disabled patients with multiple sclerosis

Defective suppressor cell function has previously been demonstrated in patients with multiple sclerosis (MS) with progressive disease and moderate degrees of disability. In the present study activated suppressor cell function was assessed in patients with documented progressive disease who, at the time of study, had experienced severe disability (Kurtzke score greater than or equal to 6.5) for at least 2 years. We found that mean suppressor levels were significantly increased in this patient group compared with the suppressor levels in the MS patient group with progressive disease but only moderate disability (Kurtzke score of less than or equal to 6.0 within 2 years of study) (59 +/- 8% vs 19 +/- 7%, respectively, p less than 0.01). The mean value in the latter group was significantly reduced compared with the mean value for normal control subjects (47 +/- 4%, p less than 0.01), a finding consistent with previous reports. The results of this study indicate that suppressor cell function, as measured by our assay system, need not be defective in MS patients who have become severely disabled from the progressive form of the disease. Whether the patients who are now severely disabled from progressive MS passed through a phase of disease associated with the same suppressor defects as found in the progressive patients currently with moderate disability will remain speculative until long-term longitudinal studies are performed.     

Electrophysiological observations on the human pudendo-anal reflex.

A reproducible electrophysiological technique is described to determine the latency of reflex contraction of the external anal sphincter in response to stimulation of the dorsal genital nerve: the pudendo-anal reflex. This was studied in 38 asymptomatic control subjects and 20 women with neurogenic faecal incontinence, supplemented by determination of the mean motor unit potential duration (MUPD) of the external anal sphincter and anorectal manometry. The reflex latency in the control group was 38.5 +/- 5.8 (SD) ms and appeared to be independent of age or sex. Three patients with faecal incontinence had absent reflexes; the remainder showed significant prolongation of latency (56 +/- 12.2 SD ms) and diminution of amplitude. MUPD was prolonged in incontinence and showed significant correlation with the corresponding reflex latency determination (tau = 0.56, p less than 0.001). The latency of this polysynaptic spinal reflex hence provides a reliable index of neuropathy of the external anal sphincter.     

Clinically benign multiple sclerosis despite large T2 lesion load: can we explain this paradox?

Magnetic resonance imaging (MRI) techniques such as magnetization transfer imaging and magnetic resonance spectroscopy (MRS) may reveal otherwise undetectable tissue damage in multiple sclerosis (MS) and can serve to explain more severe disability than expected from conventional MRI. That an inverse situation may exist where non-conventional quantitative MRI and MRS metrics would indicate less abnormality than expected from T2 lesion load to explain preserved clinical functioning was hypothesized. Quantitative MRI and MRS were obtained in 13 consecutive patients with clinically benign MS (BMS; mean age 44 +/- 9 years) despite large T 2 lesion load and in 15 patients with secondary progressive MS (SPMS; mean age 47 +/- 6 years) matched for disease duration. The magnetization transfer ratio (MTR), magnetization transfer rate (kfor), brain parenchymal fraction (BPF) and brain metabolite concentrations from proton MRS were determined. BMS patients were significantly less disabled than their SPMS counterparts (mean expanded disability status score: 2.1 +/- 1.1 versus 6.2 +/- 1.1; P < 0.001) and had an even somewhat higher mean T2 lesion load (41.2 +/- 27.1 versus 27.9 +/- 24.8 cm3; P = 0.19). Normal appearing brain tissue histogram metrics for MTR and kfor, mean MTR and kfor of MS lesions and mean BPF were similar in BMS and SPMS patients. Levels of N-acetyl-aspartate, choline and myoinositol were comparable between groups. This study thus failed to explain the preservation of function in our BMS patients with large T2 lesion load by a higher morphologic or metabolic integrity of the brain parenchyma. Functional compensation must come from other mechanisms such as brain plasticity.     

Oral yohimbine in human autonomic failure

Yohimbine is an alpha 2-adrenoreceptor antagonist that acts to enhance sympathetic nervous system discharge and potentiate sympathetically mediated cardiovascular reflex responses. We therefore assessed the ability of yohimbine to increase sympathoadrenal discharge and raise blood pressure (BP) in patients with autonomic failure characterized by profound orthostatic hypotension. Yohimbine 5 mg orally in eight seated patients significantly elevated mean systolic BP by 33 mm Hg from 136 +/- 15 (mean +/- SD) to a maximum of 169 +/- 23 mm Hg (p less than 0.01), mean diastolic BP by 16 mm Hg from 77 +/- 9 to a maximum of 93 +/- 15 mm Hg (p less than 0.01), and mean heart rate (HR) by 10 beats per minute (BPM) from 68 +/- 12 to a maximum of 78 +/- 17 BPM (p less than 0.01). Plasma norepinephrine (NE) increased from 104 +/- 71 to a maximum of 196 +/- 182 pg/ml (p less than 0.05), but plasma epinephrine (E) did not increase significantly (31 +/- 18 versus a maximum of 39 +/- 21 pg/ml). In five patients given yohimbine 2.5 mg orally, BP, HR, NE, and E tended to increase, but the changes were not significant. Plasma yohimbine levels correlated significantly with the changes in mean arterial pressure (r = 0.61, p less than 0.01). Yohimbine raises BP and HR in patients with autonomic failure. These effects are dose- and concentration-dependent and mediated through increased sympathetic discharge. Yohimbine may be useful in the treatment of orthostatic hypotension associated with autonomic failure. It is unique among current modes of therapy for this disorder in that it enhances discharge of the patient's own sympathetic system.     

The window of therapeutic opportunity in multiple sclerosis

From 1991–2002, we treated 58 patients with multiple sclerosis (MS) using the humanised monoclonal antibody, Campath–1H, which causes prolonged T lymphocyte depletion. Clinical and surrogate markers of inflammation were suppressed. In both the relapsing–remitting (RR) and secondary progressive (SP) stages of the illness, Campath–1H reduced the annual relapse rate (from 2.2 to 0.19 and from 0.7 to 0.001 respectively; both p < 0.001). Remarkably, MRI scans of patients with SP disease, treated with Campath–1H 7 years previously, showed no new lesion formation. However, despite these effects on inflammation, disability was differently affected depending on the phase of the disease. Patients with SPMS showed sustained accumulation of disability due to uncontrolled progression marked by unrelenting cerebral atrophy, attributable to ongoing axonal loss. The rate of cerebral atrophy was greatest in patients with established cerebral atrophy and highest inflammatory lesion burden before treatment (2.3 versus 0.7 ml/year; p = 0.04). In contrast, patients with RR disease showed an impressive reduction in disability at 6 months after Campath–1H (by a mean of 1.2 EDSS points) perhaps owing to a suppression of on–going inflammation in these patients with unusually active disease. In addition, there was a further significant, albeit smaller, mean improvement in disability up to 36 months after treatment.We speculate that this represents the beneficial effects of early rescue of neurons and axons from a toxic inflammatory environment, and that prevention of demyelination will prevent long–term axonal degeneration. These concepts are currently being tested in a controlled trial comparing Campath–1H and IFN–beta in the treatment of drug–naïve patients with early, active RR MS.     

Fatigue is not associated with raised inflammatory markers in multiple sclerosis

BACKGROUND: The pathogenesis of fatigue in patients with MS is poorly understood. OBJECTIVE: To test the hypothesis that fatigue in MS is related to inflammatory disease activity as measured by systemic markers of inflammation. METHODS: Fatigue as assessed by the Fatigue Questionnaire Scale (FQS) and Krupp's Fatigue Severity Scale (KFSS) was correlated with several inflammatory markers in 38 patients with MS (16 relapsing-remitting [RR; 7 of whom had benign MS), 9 secondary progressive [SP], 13 primary progressive [PP]). The markers included daily urinary neopterin excretion, a marker of interferon-gamma-activated macrophage activity, and serum C-reactive protein (CRP) and soluble intercellular adhesion molecule-1 (sICAM-1) levels. Urinary neopterin excretion was measured daily for 2 weeks. RESULTS: No correlation was found between urinary neopterin excretion, CRP, or sICAM-1 and the fatigue scores. However, patients with a raised serum CRP level had higher KFSS, but not FQS, scores than patients with normal CRP levels (KFSS, 50 +/- 8 vs 41 +/- 14, p = 0.05; FQS, 13 +/- 4 vs 11 +/- 5, p = NS). When assessed using the FQS, patients with RR and SP MS were more fatigued than patients with PP MS (RR = 12.5 [4 to 23] vs SP = 13 [8 to 18] vs PP = 9 [7 to 14], p = 0.02). The patients with benign MS were as fatigued as patients with nonbenign disease. CONCLUSION: The pathogenesis of fatigue in MS is complex and does not appear to be directly related to systemic markers of inflammatory disease activity. Interestingly, patients with PP MS were less fatigued than patients with RR disease.     

The role of osteopontin: A shared pathway in the pathogenesis of multiple sclerosis and osteoporosis?

Osteopontin (OPN) was suggested to have a role in the pathophysiology of MS and in bone metabolism. However, we formerly reported increased presence of osteoporosis in MS patients independent of corticosteroid treatment, there is only limited information about the mechanism of bone loss. In this study, we investigated the role of OPN on bone mineral density in MS patients. Thirty-three relapsing-remitting (RR), 12 secondary progressive (SP), and 5 primary progressive (PP) MS patients and 30 healthy controls were prospectively enrolled. Students' t test, chi-square test, and Pearson correlations were used. The mean OPN level was 155.4+/-81.8 ng/ml in controls, and 15.9+/-36.2 ng/ml in MS patients (p<0.001).No statistical difference was observed among RR, SP and PPMS patients (p=0.162). No relationship was found between OPN levels and age at onset of disease (p=0.830), gender (p=0.785), MS subtypes (p=0.330), disease duration (p=0.744), or EDSS scores (p=0.633).About 34% of MS patients versus 10.3% of controls had osteoporosis (p=0.017).Osteopontin levels showed no significant correlation with osteoporosis in controls, but were lower in MS patients with osteoporosis in femur neck (r=0.85, p=0.010).The cumulative dose of corticosteroid treatment did not correlate with OPN levels (p=0.285).In conclusion, our results suggest that OPN may have a role as a shared cytokine in pathogenesis of MS and osteoporosis.     

Secondary progressive multiple sclerosis - clinical course and potential predictive factors

BACKGROUND AND PURPOSE: To characterize the course of secondary progressive multiple sclerosis (SPMS), with an attempt to assess the predictive value of early clinical variables. MATERIAL AND METHODS: Medical records of 100 patients with SPMS (40 men, 60 women, aged 34-73) were analyzed retrospectively. Age at onset of MS, first symptoms, annual exacerbation rate (AER), time to progressive phase (TTP), degree of disability at its beginning (Expanded Disability Status Scale; EDSS SP), and annual progression in disability in relapsing-remitting and progressive phases (APD RR and APD SP) were compared for the gender subgroups, and the relationships between them were analyzed. RESULTS: Time to progressive phase range was 2-29 years (mean 11.51) and EDSS SP 2-7.5 (mean 5.55). Time to progressive phase in women was longer and EDSS SP was lower than in men. Age at onset of MS, AER and ADP RR correlated positively with TTP. Optic neuritis was the most common first symptom (49%; motor deficit and cerebellar/brainstem involvement 26% and 21%, respectively). Time to progressive phase in the former subgroup was shorter than in the latter, but no differences in ADP SP were found. Annual progression in disability in relapsing-remitting was higher than APD SP. Degree of disability at its beginning (EDSS SP) correlated negatively with ADP SP. CONCLUSIONS: Older age at onset, male gender, frequent relapses and fast increase in disability in the relapsing-remitting phase are risk factors for conversion to SPMS. Increase in disability during the progressive phase is slower than in the relapsing-remitting phase and depends mainly on initial EDSS. Individual variability of the course of MS has to be considered.     

Information processing characteristics in subtypes of multiple sclerosis

The purpose of this study was to evaluate information processing characteristics in patients with multiple sclerosis (MS). We selected 53 patients with MS and 58 matched healthy controls. Using computerized tests, we investigated focused, divided, sustained attention, and executive function, and attempted to pinpoint deficits in attentional control to peripheral or central processing stages. The results substantiate the hypothesis that the slowing of attention-demanding (controlled) information processing underlying more complex cognitive skills is general, i.e. irrespective of type of controlled processing, with MS patients being 40% slower than controls. MS patients may suffer from focused, and divided and sustained attention deficits, as well as from compromised central processing stages, with secondary progressive (SP) patients showing the most extensive range of deficits, closely followed by primary progressive (PP) patients, while relapsing-remitting (RR) patients appear to be much less affected. General slowing appears to be highest in PP and SP type MS patients (50% slower) versus relapsing-remitting MS (24% slower). In contrast to most previous results, (complex) processing speed appeared to be robustly correlated with severity of MS as measured by the expanded disability status scale and with disease duration. Patients did much less differ in accuracy of processing from controls, suggesting the importance of using time strategies in planning everyday life and job activities to compensate for or alleviate MS-related speed handicaps.     

Magnetization transfer ratio of the spinal cord in multiple sclerosis: relationship to atrophy and neurologic disability.

The authors compare the spinal cord magnetization transfer ratio (MTR) of multiple sclerosis (MS) patients to healthy volunteers, relate MTR to spinal cord atrophy, and relate these and other magnetic resonance (MR) imaging parameters to disability. Sixty-five patients with MS (14 relapsing remitting [RR], 34 secondary progressive [SP], and 17 primary progressive [PP] MS), and 9 healthy volunteers were studied using MR at 1.0 T. Disability of the patients was assessed using the expanded disability status scale (EDSS). Magnetic resonance parameters were upper spinal cord MTR, number of focal spinal lesions, presence of diffuse abnormalities, and spinal cord cross-sectional area (CSA). Correlations were assessed using Spearman's rank correlation coefficient (r). Magnetization transfer ratio was higher in the controls (median, 33%; range, 30%-38%) than in patients with MS (median, 30%; range, 16-36; p < 0.05). In patients with MS EDSS correlated with spinal cord MTR, albeit weakly (r = -0.25, p < 0.05). Correlation between EDSS and spinal cord CSA was better (SRCC = -0.40, p < 0.01). No correlation was found between MTR and CSA (r = 0.1, p = 0.4). Combining MTR with spinal cord CSA improved correlation with EDSS (r = -0.46, p < 0.001), suggesting an independent correlation between disability and these 2 MR parameters. Expanded disability status scale scores were higher in patients who had diffuse spinal cord abnormality regardless of focal lesions (median, 6; range, 1.5-7.5) than in patients without diffuse abnormalities (median, 3.5; range, 0-8; p < 0.01). CSA was lower in patients with diffuse spinal cord abnormality (median, 62; range, 46-89 mm2) than in patients without diffuse abnormalities (median, 73; range, 47-89 mm2; p < 0.01). MTR was slightly lower in patients with diffuse spinal cord abnormalities (median, 29; range, 21%-33%) than in patients without diffuse abnormalities (median, 31; range, 16-36; t-test, p < 0.05).