Isfahan Multiple Sclerosis Society Research Articles

Epidemiological and clinical features of pediatric-onset multiple sclerosis: A population-based study in Isfahan, Iran, between 1997-2020

Background: Pediatric-onset multiple sclerosis (POMS) is an autoimmune demyelinating disorder of the central nervous system (CNS), affecting individuals younger than 18 years of age. We sought to characterize the epidemiological and clinical features of patients with POMS in Isfahan, Iran, from April 1997 to March 2020. Methods: The medical records of patients with POMS in the databases of Isfahan Department of Public Health and Isfahan Multiple Sclerosis Society (IMSS) were retrospectively reviewed. The 2006 and 2016 Isfahan Province population censuses were used as reference values for assessing the temporal trend of POMS. Results: From April 1997 to March 2020, 509 individuals under18 years of age were diagnosed with POMS in Isfahan. 404 of these patients (79.4%) were girls, and 105 patients (20.6%) were boys (a female to male ratio of 3.85:1). Most of the patients (83%) were monosymptomatic at onset, with optic neuritis and brainstem-cerebellar disorders being the most frequent initial presentations. Mean ± standard deviation (SD) of age at disease diagnosis was 15.8 ± 2.5 years (ranging from 3 to 18, mode = 18).From April 2019 to March 2020, the crude prevalence and the crude incidence rate of the POMS were 5.42 per 100000 and 1.86 per 100000, respectively. Poisson regression analysis revealed a 3.4% increase in the incidence rate of POMS from April 1997 to March 2020 [relative rate:1.034, 95% confidence interval (CI): 1.021-1.048]. Conclusion: The female to male ratio in our cohort was significantly higher than any other studies conducted previously. The high female to male ratio and increasing incidence of the disease suggest increasing regionalization of care.

Cyclophosphamide Versus Rituximab in Progressive Forms of Multiple Sclerosis

This study aimed to compare the efficacy of rituximab versus Cyclophosphamide on active secondary progressive multiple sclerosis (SPMS). The randomized clinical trial was performed from 2015 to 2017 in multiple sclerosis (MS) clinics affiliated to Isfahan MS society (IMSS). Patients were randomized to two groups, and one of them received Rituximab that was repeated every six months in case of medical indication. The other one received a monthly pulse of methylprednisolone plus cyclophosphamide (Endoxan, Baxter, UK) until two years. Expanded disabilities status scale (EDSS), clinical, and MRI findings were assessed every six months. Statistical analysis was performed using SPSS software. 39 patients in the Rituximab group and 30 in the Cyclophosphamide group with similar age and gender distribution were entered for analysis. At baseline, the mean number of attacks in the Rituximab group was significantly more than the Cyclophosphamide group (P=0.0001). After 6, 12, and 18 months of treatment, the rate of attacks was similar between groups although it increased significantly in the Rituximab group (P=0.030) after 24 months of treatment. EDSS was increased in the Rituximab group more than the other group at the end of the study. Both drugs were well-tolerated by patients. The EDSS was increased in the Rituximab group but the disability score did not worsen in the Cyclophosphamide group. Both therapies were associated with a reduction in disease attacks and improvement in radiologic findings in a two-year period of follow-up. © 2019 Tehran University of Medical Sciences. All rights reserved. Acta Med Iran 2019;57(8):484-491.

Multiple sclerosis among Afghan immigrants in Isfahan, Iran

BackgroundMultiple sclerosis is a central nervous system demyelinating disease with unknown etiology. However, it is believed to be a multifactorial disease resulting from an interaction of genetic and environmental factors. Immigrant studies have been performed to provide a better view of the pattern of this interaction. We aimed to report the prevalence of MS Afghan immigrants of Isfahan, a population who share the same environment as Isfahan residents but with different genetic backgrounds. Patients and methodsMedical documents of 4536 patients registered by Isfahan Multiple Sclerosis Society (IMSS), the only MS registry in the province of Isfahan, were reviewed for Afghan patients and the demographic and clinical characteristics. The information on the current population of Afghans residing in the province was gathered through Bureau for Aliens and Foreign Immigrants Affairs (BAFIA). ResultsSix Afghan cases were identified among 4536 patients registered by IMSS. Current population of Afghans in the province was 123,578 people (65,041 male and 58,537 female). One of the cases was male and the other five were females with a female/male ratio of 5:1. Sex-adjusted prevalence for males and females was 1.53 and 8.54 per 100,000, respectively. The overall crude prevalence for Afghan population of Isfahan is 4.85 per 100,000. ConclusionThis study shows a lower prevalence of MS among Afghan residents of Isfahan compared to the overall prevalence of the province. Our result could be implying a stronger bond between genetic factors and developing MS, rather than the environmental factors.

Cancer risk among patients with multiple sclerosis: A cohort study in Isfahan, Iran.

Background:Multiple sclerosis (MS), a central nervous system (CNS) autoimmune disorder, affects 2.3 million people around the world. Cancer kills around 7.5 million people annually. Both diseases have similar risks and intertwining molecular causes. Most studies focusing on MS and cancer have found an insignificant difference or reduction in the amount of cancer found in the MS community.Methods:We performed a cohort study using data from Isfahan Multiple Sclerosis Society (IMSS) and Isfahan cancer society and followed-up for 8 years on average (2006-2014). All of the 1718 MS patients were diagnosed according to McDonald’s criteria, then standardized incidence ratio and the numbers of expected cancer case were calculated.Results:While patients had an insignificant change in cancer prevalence, men had fewer cancer cases and women showed an increased prevalence of cancer. Certain types of cancer proved statistically significant. Breast cancer, nervous system cancers, and lymphoma were elevated in the cohort.Conclusion:Our results support the hypothesis that MS significantly affects certain cancers in a protective or associative manner. All cancer rates, except breast cancer, cancers located in the nervous system, and lymphomas were reduced in cohort, suggesting that unregulated immune function may provide protective effects to MS patients against cancer.

THE EFFECT OF EDUCATIONAL INTERVENTION ON KNOWLEDGE AND SELF-EFFICACY FOR PAIN CONTROL IN PATIENTS WITH MULTIPLE SCLEROSIS.

Introduction:Multiple Sclerosis (MS) is one of the most common autoimmune diseases affecting the central nervous system. The prevalence of it is increasing in our country too. The pain from disorders can affect quality of life. Several studies have pointed to the improvement of patients through educational intervention. This study attempted to evaluate the effectiveness of an educational intervention based on raising the awareness and self-efficacy for pain control among patients with multiple sclerosis during 2015 under the coverage of Isfahan MS Society (IMSS).Materials and methods:This was a quasi-experimental study involving pre-test, post-test and randomized control group conducted on 100 patients with MS referred to the Isfahan MS Society (IMSS). The educational intervention group learned the pain management self-care lesson during 4 weekly sessions. The data were collected through a self-structured questionnaire with adequate validity and reliability, containing demographic data, awareness and self-efficacy of pain control. The data were assessed through descriptive and analytical tests assisted by SPSS 17. The significant level was considered as P<0.05.Results:Concerning the questionnaire, 96% of the items were responded. Most participants were women. The frequency distribution of demographic variables was not significantly different between the two pre-test groups. After the intervention, the mean score of knowledge and efficacy among patients in the intervention group was significantly higher than the control group (P<0.001).Conclusions:Educational interventions can improve awareness and self-efficacy for pain control among patients with MS. Therefore, such interventions can be designed to reduce physical and psychological complications following multiple sclerosis.

Bilateral optic neuritis as the presenting symptom of multiple sclerosis

Background: Optic neuritis (ON) is one of the earliest manifestations of multiple sclerosis (MS). The prevalence of bilateral ON (BON) as the presenting symptom is not clear. The aim of this study was to evaluate the prevalence of BON as the presenting symptom in MS and compare it with unilateral ON (UON). Subjects and Methods: In this study, two groups of definite MS patients according to the McDonald's criteria were enrolled: Thirty patients with BON and fifty persons with UON (selected randomly from all of the UON patients) as the presenting manifestation. The patients' data were collected from the Isfahan MS Society Registry. The SPSS 22 software was used for analysis of the data. P Results: Thirty of 3972 MS patients presented with BON. The mean of their ages was 26.00 ± 6.29 in BON and 30.10 ± 8.25 in UON group ( P = 0.015). Twenty-five of BON patients were females, and five were males and in the UON group, 42 were females, and eight were males. Expanded disability status scale was 1.83 ± 1.17 in BON and 1.84 ± 1.25 in UON group ( P = 0.975). The severities of relative afferent pupillary defect (RAPD) (in pluses) were 2.00 ± 0.52 and 1.43 ± 0.72 in two groups, respectively. Conclusions: The prevalence of BON as the presenting symptom was about 0.7%. The patients who presented with BON were younger at the time of diagnosis when they were compared with those who diagnosed with UON and also had a more severe RAPD. BON could be considered as one of the important presenting manifestations of MS.

Effect of Fingolimod on Platelet Count Among Multiple Sclerosis Patients.

Background:While many studies have previously focused on fingolimod's effect on immune cells, the effect it has on circulating and local central nervous system platelets (Plts) has not yet been investigated. This study will elucidate what effects fingolimod treatment has on multiple sclerosis (MS) patients’ plasma Plt levels. In addition, it will propose possible reasoning for these effects and suggest further investigation into this topic.Methods:This quasi-experimental study used patients from the Isfahan Multiple Sclerosis Society to produce a subject pool of 80 patients, including 14 patients who ceased fingolimod use due to complications. The patients had their blood analyzed to determine Plt levels both 1-month prior to fingolimod treatment and 1-month after fingolimod treatment had been started.Results:The mean level of Plts before initiation of fingolimod therapy (Plt1) among these MS patients was 256.53 ± 66.26. After 1-month of fingolimod treatment, the Plt level yielded an average of 229.96 ± 49.67 (Plt2). This number is significantly lower than the average Plt count before treatment (P < 0.01).Conclusions:MS patients taking oral fingolimod treatment may be at risk for side-effects caused by low Plt levels. This may not be a factor for patients with higher or normal Plt levels. However, a patient with naturally low Plt levels may experience a drop below the normal level and be at risk for excessive bleeding. In addition to these possible harmful side-effects, the decreased Plt population may pose positive effects for MS patients.

P006 - Association between trigeminal neuralgia and multiple sclerosis: A population-based study

Background Multiple sclerosis (MS) is a chronic neuro-inflammatory disease of central nervous system (CNS) which is characterized by variable evolution and different clinical manifestations. Although pain is one of the most common problems of MS patients, the presence of trigeminal neuralgia (TN) in a patient's life-span is rare. Methods In a retrospective study, we investigated the presence of TN amongst MS patients inspecting total Isfahan multiple sclerosis (TIMs) records which were registered in Isfahan Multiple Sclerosis Society (IMMS) from April 2003 until July 2014. Results We could find 20 cases with diagnosis of both TN and MS, suggesting a significant higher prevalence of TN among MS patients (0.4%) in comparison with general population (0.04%) (P?0.05). Conclusions Our results showed a significant association between these two disorders supporting previous hypothesis based on the role of MS in etiology of TN. Multiple sclerosis (MS) is a chronic neuro-inflammatory disease of central nervous system (CNS) which is characterized by variable evolution and different clinical manifestations. Although pain is one of the most common problems of MS patients, the presence of trigeminal neuralgia (TN) in a patient's life-span is rare. In a retrospective study, we investigated the presence of TN amongst MS patients inspecting total Isfahan multiple sclerosis (TIMs) records which were registered in Isfahan Multiple Sclerosis Society (IMMS) from April 2003 until July 2014. We could find 20 cases with diagnosis of both TN and MS, suggesting a significant higher prevalence of TN among MS patients (0.4%) in comparison with general population (0.04%) (P?0.05). Our results showed a significant association between these two disorders supporting previous hypothesis based on the role of MS in etiology of TN.

P054 - MS and cancers

Many studies have been performed throughout the universe suggested that there might be associations between multiple sclerosis and many tumors, such as Hodgkin lymphoma, brain tumors, nasopharyngeal carcinoma and particularly breast cancer. However, cancer occurrence in patients suffering from multiple sclerosis is a fact that still requires more studies. In this study, we followed 1391 multiple sclerosis patients of Isfahan multiple sclerosis society from 2004 to 2013. The ratio of observed cases to the number of expected standardised incidence ratio (SIR) was applied as an indication of relative risk. During this time 50 cases of cancers were occurred in 1391 multiple sclerosis patients with 8346 person-years follow up (SIR=0.97 [CI=0.95%]). Furthermore, adjusting for age and gender has yielded similar results. We also found that incidence of breast cancer among multiple sclerosis patients is significantly higher than general population. This study suggested that it is not imperative that multiple sclerosis patients be at an increased risk of cancer, however women with multiple sclerosis might be at an increased risk of developing breast cancer a little more.

The psychometric properties of pain self-efficacy questionnaire in multiple sclerosis patients

Background: Given the importance of pain self-efficacy in adapting to chronic pain, the aim of the present study was to determine the psychometric properties of Self-Efficacy Questionnaire (PSEQ) in patients with Multiple Sclerosis (MS). Methods: The sample consisted of 237 patients with MS that were selected through convenience sampling in Isfahan MS Society. The participants completed the Persian version of Self Questionnaire (PSEQ) and West-Haven Multidimensional Inventory (WHMPI). The factor structure of Self Scale was evaluated by exploratory factor analysis. The internal consistency of the questionnaire was measured by Cronbach’s alpha. Spearman-BrownSplit-Half reliability and concurrent validity of this scale were also examined. Results: The findings indicated that the internal consistency of the scale was (a=0.896). Spearman-Brown Split-Half reliability coefficient was equivalent to 0.85. Results of factor analysis indicated a factor called Pain Self- Efficacy that accounted for 52.511% of the total variance with minimal factor loading of 0.6. Moreover, the significant correlation between PSEQ and 4 subscales of WHMPI indicated an acceptable concurrent validity for this questionnaire. Conclusion: Findings suggested that Self-Efficacy Questionnaire (PSEQ) has appropriate psychometric properties that might be applicable in research and practice with multiple sclerosis patients.

Pediatric Multiple Sclerosis with Primary Progressive Course—Report of a Retrospective Cohort Study in Iran

The aims of this study were to suggest the rate of primary progressive (PP) subtype of pediatric onset multiple sclerosis (MS) in Isfahan, Iran, and describe its clinical and paraclinical features. The data of patients were retrieved from Isfahan MS Society (IMSS) database from April 2003 to August 2011. Among 3,843 MS patients of Isfahan who have been registered in IMSS, 260 patients had onset symptom when younger than the age of 18 years, of whom, 11 patients had a PP course (4.23%). The mean age at onset in pediatric primary progressive multiple sclerosis (PPMS) was 16 years (range: 13 to 17) with female preponderance (2.66:1) and disease duration of 4.73 ± 3.03 years. Ataxia was the most frequent initial symptom (7/11). Additionally, the mean Expanded Disability Status Scale and progression index was 4.31 ± 0.60 and 1.50 ± 1.21, respectively. Cerebrospinal fluid analysis showed oligoclonal immunoglobulin G bands in seven patients. Magnetic resonance imaging (MRI) demonstrated periventricular lesions in all 11 patients and spinal lesions in 9 patients. Exposure to parental smoking was recorded in seven individuals. In conclusion, PPMS is an uncommon subtype of pediatric onset MS. Cerebral lesions are more common MRI findings in pediatric PPMS patients than that in adults. The course of PPMS seems to be more progressive in the pediatric population than in adults.

Late-onset multiple sclerosis in Isfahan, Iran.

Multiple sclerosis (MS) typically affects young adults; however, the first symptoms can occur after age 50 and is classified as late-onset MS (LOMS). In this retrospective study, we extracted the records of 3522 MS patients (2716 females and 806 males) registered in the Isfahan MS Society (IMSS) from 2003 to 2010. Next, we searched for LOMS cases. We aimed to compare these cases with 1698 non-LOMS subjects also extracted from the IMSS database. We found 48 LOMS patients (28 females and 20 males), which gave a crude frequency of 1.36%. The frequency by sex of LOMS in males (2.4%) was significantly greater than in females (1.0%, P = 0.002). The mean age at onset was 55.1 ± 4.3 years. The female to male ratio of 1.4:1 in these patients was significantly lower than in non-LOMS subjects (3.37:1, P = 0.003). The leading pattern of MS was relapsing-remitting (RR) in 62.5%, followed by primary progressive (PP) in 27.1%, and secondary progressive (SP) in 10.4%. Predominant presenting symptoms and signs were motor disturbances (35.4%), followed by brainstem (25%), optic neuritis (22.9%), and sensory related deficits (18.7%). The mean progression index (PI) in LOMS patients (0.88 ± 0.48) was significantly higher than in non-LOMS cases, 0.37 ± 0.17 (P < 0.0001). In comparing LOMS patients with the non-LOMS cohort, there was a higher frequency of the PP pattern and a higher PI in the LOMS group. In comparing other high-risk populations with the Isfahan cohort, LOMS formed a lower percentage of the total Isfahan MS population.

Better Prognosis of Multiple Sclerosis in Patients Who Experienced a Full-Term Pregnancy

Objective: We conducted a longitudinal prospective study to evaluate the long-term effect of pregnancy on the progression of multiple sclerosis (MS). Method: Parous female MS patients were extracted from the database of Isfahan Multiple Sclerosis Society (IMSS). Through comparing the annual relapsing rate during a mean of 4 years before pregnancy versus a mean of 6 years after delivery, MS progression influenced by the pregnancy was analyzed. Result: 102 female patients were included in our study. The mean annual relapsing rate 4 years prior to pregnancy was significantly higher than at the subsequent 6 years after delivery (1.06 vs. 0.45, p < 0.001). In addition, the annual relapsing rate in years prior to pregnancy was significantly higher than each trimester of gestation (p < 0.001). Furthermore, there was a 2.2-fold increased risk of having a relapse in individuals who had experienced more relapses prior to pregnancy, and a 0.8-fold decreased in the risk of having more relapses with older age at the onset of MS. Conclusion: Although the course of MS was deteriorated 3 months after delivery, it was not statistically significant comparing annual relapsing rates during the years prior to pregnancy. Moreover, the rate of disease progression slowed down in the 6-year period monitored after delivery.

Epileptic seizures in early-onset multiple sclerosis.

Early-onset multiple sclerosis (EOMS) is defined as the first presentation of symptoms in childhood (before the age of 16 years). EOMS occurs in about 0.4% to 10.5% of multiple sclerosis (MS) patients. In this retrospective population-based study we aimed to describe the clinical/paraclinical details and frequency of epileptic seizures in Iranian EOMS patients registered with the Isfahan Multiple Sclerosis Society (IMSS) from April 2003 to July 2010. EOMS cases were extracted from the Isfahan total MS cohort and included 3522 patients. A total of 117 EOMS patients (19 males and 98 females) with a mean age at onset of 14.2 ± 2.0 years (range: 7-16 years) were extracted from our database (3.3% of the total cohort). Of cases, ten (one male and nine females) had experienced at least two epileptic seizures, providing a crude prevalence of 8.5%. The frequency of epilepsy in EOMS patients (8.5%, 10/117) was significantly greater (P < 0.001) than that of non-EOMS cohort (2.0%, 71/3405). Epileptic seizures occurred before MS onset in two patients, after MS onset in seven, and at MS onset in one as the presenting symptom of the disease. Our findings mostly indicate an excessive prevalence of epileptic seizures in Iranian EOMS patients (8.5%), which is higher than any other report concerning seizures or epileptic seizures in a large MS series.

Linkage of Multiple Sclerosis and Guillain-Barre Syndrome: A Population-Based Survey in Isfahan, Iran

Background. Multiple Sclerosis (MS) and Guillain Barre Syndrome (GBS) are autoimmune demyelinating disorders of Central and Peripheral Nervous system, respectively. The coexistence of these two syndromes in an individual's life span is rare. Objectives. To inspect throughout Isfahan MS society (IMSS) records for MS cases who had history of documented GBS whether before the onset of MS or after it. Methods. This retrospective survey was carried out by analyzing the clinical records of 3,522 MS patients who were registered with IMSS, from April 2003 to July 2010. Eligible cases were requested to attend to IMSS for final clinical/paraclinical examinations. Results. Among 3,522 (2,716 women and 806 men) MS subjects, we could identify seven patients (six females and one male) with documented diagnosis of GBS. Six patients (five women and one man) had developed MS within 6.5 ± 7.0 (range: 1–16) years after being diagnosed with GBS and one (a woman) had developed GBS three years after the diagnosis of MS. Conclusion. It seems that the development of MS in individuals with history of GBS is more than a simple incidental event.

Multiple sclerosis and amyotrophic lateral sclerosis: is there a link?

To date, there are no reports studying the rate of amyotrophic lateral sclerosis (ALS) in relatives of multiple sclerosis (MS) patients and vice versa. This study was designed to look into this issue using two population-based databases of MS and ALS in Isfahan province of Iran. We have searched for any first, second or third degree familial kinship between the Isfahan MS Society database and Isfahan ALS population. We compared the rate of ALS among the population of first degree relatives of MS patients, with the crude prevalence of ALS in the general population of Isfahan. On the other hand, a reverse analysis was carried out to compare the prevalence of MS in Isfahan with its rate amongst the first degree relatives of ALS patients. We found 10 families among which five had first degree kinship. The rate of the diseases was significantly higher in both comparisons among the family members (p < 0.00001) and an odds ratios of more than 67 in both calculations showed a several-fold increase of ALS occurrence in the first degree relatives of MS patients and vice versa. In our study relatives of MS patients were significantly more prone to ALS and vice versa. This could give clues about the common features that the two disease share. Both diseases have an environmental and genetic component and these results mostly point toward genetic similarities.

Cigarette Smoking and the Risk of Multiple Sclerosis: A Sibling Case-Control Study in Isfahan, Iran

Aims: We aimed to study the smoking habits of multiple sclerosis (MS) patients and their healthy siblings in Isfahan province in Iran. Methods: MS patients registered with the Isfahan MS society database were compared to their healthy siblings who served as controls. Data regarding the smoking habits of patients and their siblings were collected using a specially designed questionnaire. Conditional logistic regression was adopted to analyze the association of smoking with the risk of MS, adjusting for age and sex. Results: There were 1,606 participants with 516 cases and 1,090 controls. After adjustments for age and sex, subjects who were ever-smokers had a significant risk of developing MS [odds ratio (OR) 2.67; 95% confidence interval (CI) 1.70–4.21; p <0.001]. Past smokers (OR 8.83; 95% CI 3.98–19.60; p < 0.001) and current smokers (OR 1.84; 95% CI 1.10–3.10; p = 0.021) had a significant risk for developing MS. Disease progression (current expanded disability status scale/disease duration) was not different between smokers and nonsmokers (0.54 ±0.42 vs. 0.49 ±0.48; p = 0.61). Conclusion: Using a sibling pair method our data confirm the association between smoking and MS. A degree of confounding due to overmatching between siblings was unavoidable, but any bias would be conservative and should have lessened the effect of smoking.

Cesarean delivery may increase the risk of multiple sclerosis

Background: Prenatal and perinatal factors are believed to contribute to the risk of developing multiple sclerosis (MS). Objective: This study was designed to evaluate whether mode of delivery (vaginal versus cesarean section), as a perinatal factor, affects susceptibility to MS. Methods: MS patients were recruited from the MS registry of Isfahan Multiple Sclerosis Society (IMSS) and were compared with their healthy siblings. Data regarding mode of delivery, birth order, and gestation week of birth were obtained through a specially designed questionnaire. Preterm or post term deliveries were excluded. We used conditional logistic regression statistics and adjusted for gender and birth order. Results: This study included 1349 participants (449 MS patients and 900 controls). Subjects who were born by cesarean section had significant risk of MS (odds ratio, OR = 2.51; 95% confidence interval, CI: 1.43–4.41; p = 0.001). There was significant MS risk for females who were born by cesarean section (OR = 2.69, 95% CI: 1.30–5.58; p = 0.008), but not for males (OR = 2.25, 95% CI: 0.90–5.63; p = 0.082). The mean age at onset was lower in MS patients born by cesarean section (24.58 ± 6.33) compared with that of patients born by vaginal delivery (27.59 ± 7.97; p = 0.041). There was no significant difference between the two groups for birth order (p = 0.417). Conclusion: Our results suggest that those born by vaginal delivery are at a lower risk of subsequent MS. These preliminary findings will need to be addressed in a much larger and preferably prospective study.

Sharp increase in the incidence and prevalence of multiple sclerosis in Isfahan, Iran

Background: The epidemiology of multiple sclerosis (MS) has changed in recent decades. Objectives: This study aimed to give an update on the prevalence and incidence of MS in Isfahan, Iran. Methods: The study population was all residents of Isfahan province during the period from April 2003 to July 2010. In April 2003, a registry of MS patients was created at the Isfahan MS Society (IMSS), which is the only referral center for MS patients in the province. Nearly all MS patients in Isfahan province are now registered with IMSS and were included in the analysis. Results: Among the 3522 registered patients, 2716 were female and 806 were male (sex ratio: 3.37 : 1), and 431 were diagnosed in 2009. This results in a prevalence figure of 73.3 (95% CI: 70.9–75.8) and an incidence of 9.1 (95% CI: 8.3–10.0) per 100,000. Conclusion: The reported prevalence and incidence figures in our study were higher than in our previous report of 2007, in which the prevalence and incidence of MS were reported to be 43.8 and 3.64 per 100,000, respectively. This dramatic increase in the prevalence of MS puts Isfahan amongst the regions with the highest prevalence of MS in Asia and Oceania and is mostly due to changing environmental factors, amongst which vitamin D deficiency seems an important factor in our population.

Frequency of myasthenia gravis in multiple sclerosis: Report of five cases from Isfahan, Iran

This study was designed to determine the frequency and clinical characteristics of myasthenia gravis (MG) in a large cohort of Persian patients with multiple sclerosis (MS) living in the province of Isfahan. We reviewed the case records of patients with definite MS (McDonald's criteria) registered in the Isfahan MS Society (IMSS) for associated MG. Of the 1,718 patients with MS in the registry, six patients were found to have both MS and MG. The prevalence after excluding one patient with insufficient data, was 291 per 100,000 (0.29%), a higher prevalence than the earlier reports. These results may support the hypothesis that MS and MG share some common immunopathogenic mechanisms.