Emergency Medical Care of Multiple Sclerosis Patients: Primary Data from the Mount Sinai Resource Utilization in Multiple Sclerosis Project

Multiple sclerosis (MS) is one of the leading causes of disability among young adults1 and presents a major health burden in the US and other Western countries. Although most MS patients initially experience the relapsing remitting form of MS (RRMS), about 40% of untreated RRMS patients will develop progressive neurological disability.2 As the clinical picture evolves, so too do the comorbidities: patients with severe disability have a higher risk of infectious complications such as urosepsis, pressure ulcers, and pneumonia, which confer significant secondary morbidity and mortality. A study of the costs associated with MS relapses found that MS patients rely heavily on the emergency department (ED) for acute care and that most of the MS-related healthcare costs were attributable to ED visits and inpatient hospital stays.3 While such previous studies have looked at the financial costs of MS, there has been no systematic analysis of ED utilization in the MS population.

In this study we investigated the acute-care needs of the MS population, with a focus on characterizing the MS population using the ED as a route for entry into the healthcare system. The study was performed at Mount Sinai Hospital, which is an academic medical center in New York with 1100 inpatient beds and that has an active ED with a catchment area that includes the affluent Upper East Side and the lower-income and ethnically diverse Harlem and Spanish Harlem communities. The Department of Neurology at Mount Sinai Hospital comprises both inpatient and outpatient services including the Corinne Goldsmith Dickinson Center for Multiple Sclerosis and a Medicaid clinic for MS patients.

This retrospective project was submitted and approved by the Mount Sinai Hospital Institutional Review Board after expedited review and waiver of informed consent had been granted. The Mount Sinai Hospital employs an information technology infrastructure called the Mount Sinai Data Warehouse (MSDW), which collects data generated by the many patient care and business transactional computer systems at Mount Sinai Hospital. Tools are available to produce reports for clinical research, quality-of-care initiatives, and process and financial improvement projects based on patient data from 2005 onwards.4

The MSDW was used to identify all patients who visited the Mount Sinai ED between January 1, 2005 and December 31, 2007. All of the diagnosis codes for the International Classification of Diseases, 9th edition applied to these patients then were searched to identify a cohort that contained the patients that had been evaluated in the ED with a diagnosis of MS recorded in their medical record. A total of 318 patients met these criteria. After thorough chart reviews performed by MS-specialized neurologists on the research team, 94 patients were excluded, either because the patient was not yet diagnosed with MS at the time of their ED visit or it was a false-positive diagnosis (the MS diagnosis was either a clerical error, or was ultimately found to be clinically incorrect). Overall, the final study population consisted of 224 MS patients who entered the ED during the 3-year study window.

The patient charts, both paper and electronic, were systematically reviewed by applying a custom-designed data abstraction form that extracted demographic data, medical history, neurological history, workup, and management performed in the ED and during hospitalization (if admitted). The patient's disease status at each visit was assessed using the Expanded Disability Status Scale (EDSS) and estimated to be mild (EDSS <4), moderate (EDSS 4-5.5), or severe (EDSS ≥6) based on the neurological history, documented neurological examination, and use of an assistive device for ambulation. The study database was created and maintained using SPSS version 16.0 (SPSS Inc., Chicago, IL, USA), and all of the statistical analyses were performed using this software. Generalized estimating equations with repeated measures were used to test for relatedness between correlated categorical variables. Generalized linear models with a Tukey adjustment or mixed models with repeated measures were used for continuous variables.

Considerable attention has been focused on the long-term management of patients with MS, with an emphasis on the development of disease-modifying therapies aimed at reducing the occurrence of relapses and slowing the accrual of disability. The acute-care needs of the MS patients has received comparatively little attention, despite the known impact of emergency medical and neurological care on patient outcomes.

Demographically, MS patients utilizing the ED for acute care tended to be underinsured, having either no insurance or being solely covered by Medicaid, which is consistent with previous studies of ED utilization for other conditions.5 The disease severity of the patients in our population was greater than that in the general MS population, since 40% of them had progressive forms of MS and more than half of the patients required an assistive device for mobility. In comparison, the MSBase, a research database for the collection of epidemiological information on people with MS globally, reports that only 32% of patients are affected by progressive MS. Only 19% of these patients had an EDSS score of between 5.5 and 8,6 whereas in our population this proportion was 54.0%.

The patients in our study were also an undertreated population, with only 50% of RRMS patients reporting receiving a DMT. Data published in 2000 by the National Consortium of Multiple Sclerosis Centers7 demonstrated that 67% of patients were taking a DMT and despite the increasing use of these agents over the past decade, the rate of DMT use in our cohort was considerably lower at 41.5%. In summary, we found that MS patients seeking medical care at the Mount Sinai ED were in general underinsured, undertreated, and more severely impaired than the general MS population. These data suggest that this population of MS patients is using the ED as a source of primary care.

Neither the acuity nor severity of the presenting complaints were correlated significantly with presenting to the ED after hours or on weekends, when outpatient medical and neurological care would be unavailable. Furthermore, most ED visits were not referred by a physician, which suggests that these patients were often using the ED as a source of first-line healthcare. Care and resources are provided to patients seen in the Mount Sinai ED or admitted to the hospital irrespective of their insurance status or ability to pay. While this ensures that acute-care needs are met, ongoing outpatient care needs may be more difficult to fulfill. Previous studies have shown that a lack of insurance is a barrier to primary healthcare access.8 This finding also appears to pertain to our population, since despite the background of an MS diagnosis, neurological chief complaints accounted for only one-quarter of the ED visits, and a diagnosis of an MS exacerbation was made only 13% of the time. In 2008, Marrie et al.9 reported that medical comorbidities are common in MS patients: 77.1% of their population had at least one comorbid condition. Our results support these findings, since 1) most of the chief complaints were nonneurological and 2) most of the diagnoses made in the ED were either indirectly related or unrelated to the underlying MS diagnosis. Our results suggest that improved outpatient management of the comorbidities in this MS population could yield a decreased reliance on the ED for these purposes.

The severity of a patient's MS was associated with the reason for their visit to the ED. Patients with EDSS scores reflecting mild-to-moderate MS were significantly more likely to present with complaints directly related to their MS, such as MS exacerbations, optic neuritis, and worsening of their chronic symptoms. In contrast, patients with EDSS scores reflecting severe MS were more likely to present with problems indirectly related to their MS such as pneumonia, UTIs, falls, pain, decubitus ulcers, and sepsis. MS patients with severe disease (EDSS ≥6) were more than threefold more likely to be given diagnoses that were indirectly related to MS (52.6%) than patients with an EDSS score of <6, in whom diagnoses that were indirectly related to MS were made only 14.6% of the time (p<0.0001). Notably, in patients with an EDSS score of ≥6, diagnoses directly related to MS accounted for only 10.7% of visits. This provides a clear indication of the evolving acute-care needs during the disease course, and the resources that must be utilized across the spectrum of MS severity. Recognizing that medical comorbidities and indirectly related complications of MS are the main causes of ED visits for MS patients, care should be taken to avoid "over-ascribing" the symptoms of an acutely ill MS patient directly to their underlying diagnosis of MS.

Three-quarters of the MS patients who sought ED care in this study did so for nonneurological chief complaints, and similarly three-quarters of those admitted were admitted to nonneurology inpatient services. These data validate the importance of interdepartmental awareness of the medical needs of the MS population. In 2005, Stettler et al.10 reported that neurology education in emergency-medicine residency training programs focuses on the management of neurological emergencies rather than on issues pertaining to the management of chronic neurological conditions. The results of the present study indicate that there should be a renewed emphasis on optimizing ED education pertaining to MS, so as to meet the acute-care needs of MS patients for interdisciplinary care.

This study was subject to several limitations. As a retrospective chart review, the quality of the analyses is limited by the documentation upon which it is based. For visits where a neurologist was not consulted, the neurological history and examination was performed and documented only by the ED, limiting our ability to precisely calculate the EDSS categories. However, there was sufficient documentation to characterize disease severity into mild, moderate, and severe categories. In addition, this study involved a single-center population, and as our study hospital is a large, urban, tertiary-care academic medical center, the results may reflect this selection bias and may not be generalizable to other populations. The patient populations seen at different types of hospital may have a different mix of socioeconomic status, insurance coverage, and DMT utilization. While the demographics of this population are specific to the catchment area served by Mount Sinai Hospital, the associations between high disease severity, poor insurance status, and underutilization of MS treatments are likely to be universal. Studies have suggested that a rural location can also limit the access to healthcare in general11 and to MS patients in particular.12

The purpose of this resource-utilization project was to identify opportunities to improve the ED management of MS patients by describing the population most likely to utilize the ED and to report several trends in their presentations, hospital courses, and resources utilized in their care. Subsequent studies in this project will look specifically and in detail at the assessment and management of MS relapses in the ED, the diagnostic accuracy of the ED in managing MS patients, and factors that lead to the disproportionate usage of the ED by a subpopulation of MS patients. Future objectives include repeating these analyses on data covering subsequent years, and determining how ED utilization and acute-care management in the MS population affect both short- and long-term disease outcomes, as well as improving MS patient care through interdisciplinary education.