Optic neuritis in Orientals and Caucasians

Incidence of Optic Neuritis and the Associated Risk of Multiple Sclerosis for Service Members of U.S. Armed Forces

INTRODUCTION

Optic neuritis (ON), an acute inflammation of the optic nerve resulting in eye pain and temporary vision loss, is one of the leading causes of vision-related hospital bed days in the U.S. Military and may be a harbinger of multiple sclerosis (MS). We developed a case identification algorithm to estimate incidence rates of ON and the conversion rate to MS based on a retrospective assessment of medical records of service members (SMs) of the U.S. Armed Force.

MATERIALS AND METHODS

Electronic medical records (EMRs) from 2006 to 2018 in the Defense Medical Surveillance System were screened using the case identification algorithms for ON and MS diagnosis. The incidences rates of ON were calculated. The rates of conversion to MS was modeled using the Kaplan-Meier survival analysis.

RESULTS

The overall incidence rate of ON was 8.1 per 100,000 from 2006 to 2018. Females had a rate (16.9 per 100,000) three times higher than males. Most (68%) of subsequent diagnoses of MS were made within 1 year after diagnosis of ON. The overall 5-year risk of progression to MS was 15% (11%-16% for 95% CI). The risk of conversion to MS in females was significantly higher than in males.

CONCLUSIONS

We developed an efficient tool to explore the EMR database to estimate the burden of ON in the U.S. Military and the MS conversion based on a dynamic cohort. The estimated conversion rates to MS feeds into inform retention and fitness-for-duty policy in these SMs.

Update on Optic Neuritis: An International View

Previously, optic neuritis was thought to be typical, i.e. idiopathic or multiple sclerosis (MS) related, associated with a good visual prognosis, or atypical, i.e. not associated with MS and requiring corticosteroids or plasma exchange for vision to recover. More recently, the importance of optic neuritis in neuromyelitis optica spectrum disorder and myelin oligodendrocyte glycoprotein (MOG) antibody disease has become more appreciated. The results of the Optic Neuritis Treatment Trial (ONTT) has influenced how optic neuritis is treated around the world. For this review we surveyed the international literature on optic neuritis in adults. Our aims were first to find the reported incidence of optic neuritis in different countries and to ascertain what percentage of cases were seropositive for anti-aquaporin 4 and anti-MOG antibodies, and second, to document the presenting features, treatment, and outcomes from a first episode of the different types of optic neuritis from these countries, and to compare the results with the outcomes of the ONTT cohort. From these data we have sought to highlight where ambiguities currently lie in how to manage optic neuritis and have made recommendations as to how future treatment trials in optic neuritis should be carried out in the current antibody testing era.

Population-based Incidence of Pediatric and Adult Optic Neuritis and the Risk of Multiple Sclerosis

PURPOSE

To determine the age- and sex-specific prevalence and incidence of demyelinating optic neuritis and the risk of multiple sclerosis (MS) in pediatric and adult populations in South Korea.

DESIGN

A nationwide, population-based, retrospective study using data from the Korean National Health Claims database from 2010 to 2016.

PARTICIPANTS

The entire South Korean population aged 65 years of age or younger (n = 44 700 564). All patients with optic neuritis from the entire Korean population were included.

METHODS

Patients aged 14 years of age or younger were classified as pediatric patients, and those aged 15 to 65 years were classified as adults. Each group was analyzed separately. Patients with optic neuritis had a subsequent diagnosis, including idiopathic, MS, neuromyelitis optica (NMO), and acute disseminated encephalomyelitis. Prevalence and incidence, conversion rate to MS, and treatment modalities (steroids, plasmapheresis, interferon-β, and immunosuppressants) were estimated.

MAIN OUTCOME MEASURES

Prevalence and incidence of optic neuritis, and conversion rate to MS.

RESULTS

Among 44 700 564 individuals, 531 pediatric patients (50.7% female) and 7183 adults (53.3% female) were identified as having optic neuritis. Annual incidence was 1.04 (95% confidence interval [CI], 1.01-1.07) per 100 000 pediatric individuals and 3.29 (95% CI, 3.28-3.30) per 100 000 adults. Peak incidence was observed at 10 to 14 years in the pediatric population and at 30 to 34 years and 50 to 54 years in the adult population. Conversion rate to MS was 13.8% in the pediatric population and 11.4% in the adult population. Fourteen percent of all patients were treated with chronic immunosuppressants, 38% of patients with NMO underwent plasmapheresis, and 50% of patients with MS were treated with interferon-β.

CONCLUSIONS

This is a nationwide epidemiologic study of optic neuritis in individuals of all ages in South Korea. The incidence of optic neuritis and subsequent risk of MS in the pediatric population are comparable to those reported in western countries but are lower in the adult population than in western countries. The incidence rate in adults was 3.2-fold higher than in the pediatric population, and the overall MS conversion rate in the entire Korean population was estimated to be 10.6%.

Clinical characteristics of optic neuritis in Koreans greater than 50 years of age

Purpose

To report clinical characteristics of optic neuritis (ON) in Koreans >50 years of age.

Methods

A retrospective chart review was performed on patients with ON between January 2000 and December 2009. We obtained the best-corrected visual acuity (BCVA), Goldmann perimetry, relative afferent pupillary defect (RAPD), and color function tests as well as brain magnetic resonance imaging (MRI) findings in patients who were in the acute stage of the disorder.

Results

Nine eyes in eight patients were included. The mean age of patients at presentation was 60.5 years (range, 53 to 71 years). Six patients were female, and two were male. There was one patient with bilateral ON. The mean BCVA at presentation was 20 / 400 (no light perception-20 / 70). Eight eyes (89%) complained of pain with eye movement. Six eyes (66%) had disc edema. Central scotoma was the most common field defect. All eyes had color abnormalities. Five eyes in four patients showed abnormalities of the involved optic nerves on MRI. The patients were followed for a mean of 11.3 months (range, 2 to 34 months). All of the patients recovered to a BCVA of 20 / 40 or better within 2 months. On the last follow-up, the mean BCVA was 20 / 20 (20 / 40 to 20 / 16). Four eyes showed remnant central scotoma. One eye had remnant RAPD, and two eyes had mild color abnormalities.

Conclusions

Although ON is uncommon in elderly patients, it can develop in patients >50 years of age, and clinical features of optic neuritis in elderly patients are similar to those of younger patients.

Pattern visual evoked potentials in Japanese patients with multiple sclerosis without history of visual pathway involvement

A delay of the peak latency of the pattern visual evoked cortical potentials (pVEP) is accepted as one of the paraclinical evidence for a diagnosis of multiple sclerosis (MS). The purpose of this study was to evaluate the pVEPs in Japanese patients with MS without a history of visual pathway involvement. We studied the medical records of 29 MS patients without any history of visual pathway involvement, and with visual acuity correctable to > or = 20/20. The Goldmann visual fields, pupillary light reflexes, and optic disks were normal in all. pVEPs elicited by 3 rev/s (transient) and 12 rev/s (steady-state) were recorded from the MS patients and compared with those recorded from normal subjects. The latency of the P100 component of the transient pVEPs was significantly prolonged in 9/29 (31%) MS patients. A phase lag in the steady-state pVEPs was found in 6/29 (21%) MS patients, and the mean amplitude was significantly smaller. The incidence of cases with abnormal pVEPs is lower than that reported from Europe and United State. This difference is possibly due to racial differences, and the use of different criteria for diagnosing optic neuritis.

Is the frequency of abnormalities on magnetic resonance imaging in isolated optic neuritis related to the prevalence of multiple sclerosis? A global comparison

The link between optic neuritis and multiple sclerosis is well established, as is the increased risk of conversion to multiple sclerosis, with lesions seen at presentation on the magnetic resonance imaging (MRI) scan of the brain. One or more asymptomatic lesions were present in 77% of the optic neuritis cohort from London, UK, a higher proportion than that reported in other large cohorts studied elsewhere, where generally lower prevalence rates for multiple sclerosis are also reported. These observations may support the hypothesis that optic neuritis is more likely to be associated with abnormalities on MRI and to be due to multiple sclerosis in geographical regions where multiple sclerosis is more common.

Low Conversion Rate to Multiple Sclerosis in Idiopathic Optic Neuritis Patients in Taiwan

PURPOSE

To investigate the clinical characteristics of patients with idiopathic optic neuritis (ON) in Taiwan and to assess the conversion rate to multiple sclerosis (MS) in these patients.

METHODS

We studied the medical records of a total of 109 patients with a clinical diagnosis of idiopathic ON treated in the Taipei Veterans General Hospital during the period from January 1986 to May 2003. Clinical characteristics, management, and disease courses were retrospectively reviewed. Our main focus was on the development of multiple sclerosis after an ON attack. Univariate and multivariate analyses were used to evaluate the risk indicators for MS conversion.

RESULTS

The patients (58 women, 51 men) had a mean age of 41.2 years at onset. ON was retrobulbar in 46.8% of the patients. Management with or without pulse therapy did not affect the final visual outcome. Female sex, retrobulbar type ON, recurrent cases, elevated cerebrospinal fluid (CSF) IgG index, and central nervous system (CNS) imaging abnormalities were identified as risk indicators for the development of MS (P < 0.05). The 2-year cumulative probability of developing MS was 5.92%, and the 5-year cumulative probability was 14.28%. The conversion rate to MS did not differ among treatment groups.

CONCLUSIONS

Idiopathic ON patients in Taiwan have an older age at onset and a higher percentage of optic disc edema than reported in previous literature. The characteristic features of ON patients associated with a high risk of developing MS are female sex, retrobulbar type ON, CNS imaging abnormalities, elevated CSF IgG index, and recurrence. Idiopathic ON patients in Taiwan display a significantly lower conversion rate to MS.

Optic neuritis: clinical analysis of 27 cases

We retrospectively reviewed 27 cases diagnosed as idiopathic optic neuritis between 1992 and 2001 at Kaohsiung Veterans General Hospital to assess the clinical features, visual prognosis, neuroimaging, laboratory studies, and development of multiple sclerosis in Chinese patients with optic neuritis. Patient age ranged from 13 to 54 years (mean, 35.8 +/- 11.3 years). Five cases presented as bilateral optic neuritis and 22 as unilateral. Visual function improved gradually from 2 weeks after treatment. Twelve (44.4%) cases showed disc swelling and ocular pain was also noted in 44.4% of patients. All cases that underwent visual field and visual evoked potential tests showed abnormality in lesion eyes. Of the 23 cases that underwent neuroimaging studies, including computerized tomography (17 patients) and magnetic resonance imaging (6 patients), 10 revealed optic nerve thickening. Four cases (14.8%) developed multiple sclerosis during follow-up (mean, 4.3 years). The incidence of disc swelling was higher than that reported by the Optic Neuritis Treatment Trial, but the incidence of initial ocular pain, the presence of periventricular plaques, and the development of multiple sclerosis were lower in our study. The unilateral group had significantly better visual outcome than the bilateral group.

Ophthalmology update for primary practitioners. Part I. Update on optic neuritis

Optic neuritis is a common cause of acute visual loss. It is typified by sudden onset of visual impairment and pain with eye movements, followed by spontaneous recovery of vision over several months. Pathologically, optic neuritis is an acute demyelinating event affecting the optic nerve. Objective physical findings are typically few, including an afferent pupillary defect or Marcus-Gunn pupil, whereas subjective psychophysical findings abound (ie, diminished central visual acuity, color vision, decreased contrast sensitivity, and visual field abnormalities). These characteristics have made the diagnosis of optic neuritis based solely on clinical grounds disquieting to practitioner and patient alike. In addition, the fact that optic neuritis is often associated with multiple sclerosis as the first clinical manifestation of disease gives further reason for both patient and physician anxiety. The serious nature of visual loss and the consequences of making the diagnosis of optic neuritis has given rise to extensive testing and expensive treatments. This review is intended to explore our current state of knowledge with regard to (1) clinical presentation, (2) ancillary testing, (3) therapeutic intervention, and (4) associated disease, specifically the risk for multiple sclerosis in the patient who presents with an acute optic neuritis. Finally, a suggestion guide for informing the patient and addressing his or her concerns will be presented.

The risk of motor neurone disease and multiple sclerosis is different in Estonians and Russians. Data from South Estonia

Epidemiological studies were performed in South Estonia to establish the prevalence rate of multiple sclerosis (MS) and motor neurone disease (MND). The case finding method included information from the hospital records of the central hospital in the region-the University Hospital (for MS from 1942 to 1989), from all neurologists in the region, from the Estonian MS Society and Association of Muscular Disorders, and from nursing homes in the region. The prevalence day was 31 December 1989. MND incidence was established for the period of 1986-1995. The results demonstrated high prevalence rates of MS among native Estonians (55.3 per 100 000), somewhat lower prevalence among native-born representatives of other nationalities (43.6 per 100 000) and the lowest prevalence rate of MS among non-Estonian immigrants (26.6 per 100 000). The differences were not statistically significant. The results for MND demonstrated the opposite pattern. The mean annual incidence rate of MND for 10 years was statistically significantly higher among people of other nationalities (2.5 per 100 000) and Russians (2.6 per 100 000), and lower in native-born Estonians (1.1 per 100 000). No differences in health care or clinical picture were established. The reasons for the demonstrated differences in MND incidence remain unclear.

Incidence of optic neuritis in Stockholm, Sweden 1990-1995: I. Age, sex, birth and ethnic-group related patterns

We studied the incidence of monosymptomatic optic neuritis (MON) in Stockholm county, Sweden and its variation with person-related factors. Patients with suspected or diagnosed MON between January 1, 1990 and December 31, 1995 were referred from ophthalmologists and neurologists to a research registry. The diagnosis was based on accepted clinical criteria only, and verified by an ophthalmologist who examined all the patients. Data were collected by interview using a structured questionnaire. The crude mean annual incidence, based on 147 patients, 118 females and 29 males, diagnosed with MON, was 1.46 per 100,000 person-years, 2.28 for females and 0.59 for males. The corresponding age-adjusted incidences were 1.40, 2.28 and 0.53. The age-specific incidence curve for both sexes suggested a bimodal distribution with peaks at 30-34 years and 45-49 years. The smoothed cumulative incidences in 1 year birth cohorts showed a notchy profile, related to bimodality. The incidence among residents born out of the Nordic countries was low, 0.28 per 100,000. Patients with onset of MON before 40 years of age had a significantly higher frequency of mononuclear pleocytosis in cerebrospinal fluid and shorter duration to conversion to multiple sclerosis. In summary, MON occurred in Stockholm at a relatively low frequency, particularly among males. The presence of particular birth date and birth place related patterns might be etiologically relevant.

Isolated optic neuritis and its prognosis for multiple sclerosis: a clinical and paraclinical study with evoked potentials. CSF examination and brain MRI

Our study evaluated the frequency of developing multiple sclerosis (MS) after acute isolated optic neuritis (ON), the possible association with risk factors (gender, age), and the diagnostic and prognosis role of paraclinical tests. We studied 100 ON patients (mean age 28.9 years: SD 8.9): 85 patients were regularly followed up. Sixty-six patients underwent multimodality evoked potential (EP) test, examination and brain MRI within six months of the onset of ON. Over a mean follow-up of 5.2 years, MS occurred in 28/85 cases. The risk of developing MS after four years was 0.35 at life-table analysis, regardless of gender or age at the onset of ON. Visual EPs in unaffected eyes were abnormal in 25.4%, brainstem auditory EPs in 6.5% somatosensory EPs in 8.1%, upper limb motor EPs in 6.8% of the tested patients; intrathecal IgG synthesis was revealed in 51.7% and MRI lesions in 73.8%. Fifty-one of the patients who underwent paraclinical tests were followed up for more than one year, and MS occurred in 13 cases. All of these presented MRI lesions, nine intrathecal IgG synthesis, and two abnormal extraocular EPs. The risk of developing MS after four years was 0.33 in patients with MRI lesions; the simultaneous presence of intrathecal IgG synthesis increased the risk to 0.46.

Optic neuritis in children: recurrence and subsequent development of multiple sclerosis

Recurrent optic neuritis and the subsequent development of multiple sclerosis in children, particularly in Asian countries, are not well known. We report on recurrent optic neuritis and subsequent multiple sclerosis in 22 Thai children who were younger than 15 years of age at the onset of optic neuritis, had no previous neurologic illness, and were monitored for 6-20 years. Improvement of vision was observed in 8, 10, and 2 patients after the first, second, and third week of onset, respectively. Two patients had recurrent optic neuritis and the other 2 patients subsequently developed clinical definite multiple sclerosis characterized by hemiparesis at 6 months and myelopathy at 2 years later in 1 patient and myelopathy and brainstem dysfunction in the other at 4 and 6 years later. The frequency of subsequent development of multiple sclerosis after optic neuritis may be similar to that reported from the United States and European countries.

Clinical definition for multiple sclerosis treatment trials

Clinically, the Schumacher Panel criteria remain the best set of diagnostic criteria. Two subsets therein are definable, i.e., exacerbating-remitting (ER) and chronic progressive (CP), with the latter subdivided into progressive from onset and secondarily progressive. A clinically stable stage can also be recognized. It has been customary in treatment trials to separate ER and CP patients. End point for the latter is a comparison of neurologic status at the end of the trial with that entry. A similar assessment can be made for ER patients. With this criterion both types could be included in a single study. One could also, though, treat the exacerbation in an acute study or assess whether exacerbations can be prevented in a long-term trial. Most clinicians no longer consider monophasic disease as multiple sclerosis (MS). Depending on clinical extent, such patients are divisible into acute disseminated encephalomyelitis, Devic disease, transverse myelopathy, or optic neuritis. Each subgroup could be studied as with an acute exacerbation or in long term as to whether future and different neurologic insults can be prevented. One measure of neurologic status is the Disability Status Scale (DSS), which grades clinical impairment due to MS on a 0 (normal) to 10 (death due to MS) basis. The expanded DSS (EDSS) subdivides each step 1 through 9 into two. Type and severity of neurologic impairment is defined by graded involvement in the following eight functional systems (FS): pyramidal, cerebellar, brainstem, sensory, bowel and bladder, visual, cerebral, and other. Frequency and severity of each FS correlates strongly with DSS scores.(ABSTRACT TRUNCATED AT 250 WORDS)

The risk of multiple sclerosis developing in patients with isolated idiopathic optic neuritis in Brazil

We studied 88 patients with isolated idiopathic optic neuritis (IION) in order to evaluate the rate of progression to multiple sclerosis (MS) in Brazil. The patients were reassessed from one month to nine years after the development of the IION (mean follow-up was 4.6 years). There were 52 men and 36 women with ages ranging from three to 59 years (mean 24.3 years). Bilateral optic neuritis occurred in 19 patients whereas sequential involvement of the fellow eye after an interval longer than four weeks occurred in other 19 patients. Recurrences in the same eye occurred in seven cases. Nine patients (10.8%) developed clinically definitive MS--13.9% of the women and 7.7% of the men with IION. The median age at the time of diagnosis of MS was 25 years. The mean interval between IION and the emergence of other MS signs varied from one month to five years--median one year. Sixty-seven percent of these patients developed signs of spinal cord involvement. Our findings when compared to published series in different countries are closer to figures reported in Japan than those in the West.

Uncomplicated retrobulbar neuritis and the development of multiple sclerosis

A retrospective study of 30 patients hospitalized with a diagnosis of uncomplicated retrobulbar neuritis was carried out. The follow-up period was 2-11 years; 57% developed multiple sclerosis. When the initial examination revealed oligoclonal bands in the cerebrospinal fluid, the risk of developing multiple sclerosis increased to 79%. With normal cerebrospinal fluid the risk decreased to only 10%. In the majority of cases, the diagnosis of MS was made during the first 3 years after retrobulbar neuritis.

Optic neuritis in relation to multiple sclerosis

Available estimates of the frequency with which a patient with optic neuritis develops multiple sclerosis range from as low as 13% to as high as 87%. In an effort to obtain a better estimate, a nation-wide study of optic neuritis was carried out in Israel. Patients who fulfilled strict diagnostic criteria of optic neuritis were identified and examined periodically. Between 1955 and 1964, 105 patients were found and on the basis of these, the average annual age-adjusted incidence of optic neuritis in Israel was 0.56 per 10(5) population compared to 1.2 per 10(5) cases of multiple sclerosis per year, i.e. optic neuritis was about half as frequent as multiple sclerosis each year. As with multiple sclerosis, optic neuritis was more common in European immigrants to Israel than Afro-Asian immigrants. During a follow-up interval which ranged from 3.3 to 15.6 years (mean 9.5 years), at least 27 of the 105 patients developed multiple sclerosis (28%). A life-table analysis showed that after 10 years 32.3 +/- 5.6% of patients with optic neuritis would develop multiple sclerosis and, after 14 years, about half would develop multiple sclerosis. Risk of dissemination was highest in those who were youngest when optic neuritis developed. Neither sex nor ethnic background influenced risk significantly. Results of the present study support earlier work using life-table methods carried out in Hawaii which also showed that between 29 and 39% of patients with optic neuritis will develop multiple sclerosis within 10 years of onset. The life-table method is a better predictor of prognosis than newer laboratory techniques such as spinal fluid studies of IgG, kappa-lambda light chain ratios and serum/CSF IgG ratios.

The epidemiology of optic neuritis in Finland

Evidence has been presented that optic neuritis partially reflects benign cases of MS which are lost in the epidemiological investigation of the disease. As part of a large epidemiological investigation of MS, 221 patients with pure optic neuritis were identified during the period from January 1, 1967 to December 31, 1971. The mean annual incidence for the whole of Finland was 0.94 per 100,000 population. The female to male ratio was 1.7. The mean age at onset was 31.2 years. The distribution of optic neuritis by counties showed the highest mean annual incidence in the southwestern county of Turku and Pori (1.69) and in the western county of Vaasa (1.68). The prevalence data for MS were highest in these counties. A highly significant deviation from a random distribution according to place at onset and place of birth was obtained. Even the geographical distribution by smaller units, i.e. the combined clerical districts, revealed a firm accumulation to the western districts in the county of Vaasa and to the southwestern districts in the county of Turku and Pori. Thus, optic neuritis showed a similar geographical distribution of Jalasjärvi with several familial cases of MS did not increase the familial percentage when both conditions were considered as a single group. The risk of getting optic neuritis seems to depend on the influence of factors present during childhood. The epidemiological data point to a common factor in the aetiology of optic neuritis and MS.