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Identifying employed multiple sclerosis patients at-risk for job loss: When do negative work events pose a threat?

Multiple Sclerosis and Related Disorders, Volume 4, Issue 5, September 2015, Pages 409 - 413

Abstract

Background

Physical disability and cognitive impairment are significant predictors of unemployment in multiple sclerosis (MS). However, little is known about the frequency of work problems in employed patients, in comparison to employed healthy persons.

Objective

Use an online monitoring tool to compare the frequency of negative work events in MS patients and healthy controls, and determine a threshold at which the frequency of work problems is clinically meaningful.

Methods

The sample comprised 138 MS patients and 62 healthy controls. All reported on recent negative work events and accommodations using an online survey. The clinical test battery measured depression, motor and cognitive function. Statistical tests compared the frequency of work problems in MS patients and healthy controls. Clinical neuro-performance scales were then assessed in at-risk patients with many work problems, versus those with no work problems.

Results

As a group, employed MS patients exhibited deficits in motor ability, verbal memory, and processing speed and were more likely than controls to report negative work events and accommodations. At-risk patients, that is, those reporting more than one negative work event, had more pronounced motor and cognitive deficits than their relatively stable counterparts.

Conclusion

The data show that employed MS patients report more negative work events and accommodations than employed healthy persons. Those patients deemed at risk for job loss have more cognitive and motor impairment, suggesting the need for cognitive training and specific accommodation strategies in the work place.

Highlights

• Little is known about how frequently negative workplace events occur in MS.
• Neuropsychological and vocational survey data were collected from all participants.
• Work problems were reported more frequently in MS patients compared to controls.
• Two negative events presents as a threshold for identifying those at risk for job loss.

Keywords: Multiple sclerosis, Work accommodations, Negative work events, Disability, Cognition, Employment.

1. Introduction

The diagnosis of multiple sclerosis (MS) often occurs during early adulthood, in the prime of career development, and as such the disease contributes to high rates of unwanted unemployment (). Some research suggests that up to ½ of patients lose their job within five years of diagnosis ( Minden et al., 1993 ). Aside from the obvious financial benefits of working, employment enhances long-term health and quality of life ( Johnson et al., 2004 ).

Employment status is influenced by demographic variables and clinical factors such as physical disability, progressive disease course, depression, and cognitive dysfunction (). Cognition may be the most important factor, especially when verbal memory, mental speed, and higher executive function are considered ( Beatty et al., 1995 ; Benedict et al., 2005 ; Rao et al., 1991 ). Furthermore, perceived cognitive impairment can be related to vocational disability ( Benedict and Zivadinov, 2006 ), although it appears that neither subjectively reported or actual cognitive abilities contribute to patient decisions to disclose disease status to their employer ( Frndak et al., 2015 ).

The aforementioned studies have in large part utilized an employed/disabled dichotomy as the primary outcome. From a clinical management point of view, it is more important to understand how the process of job loss unfolds, beginning presumably with an increase in work problems and need for accommodations, eventually leading to job loss. In an attempt to better understand this process, we have embarked upon a program of repeatedly monitoring negative work events and accommodations using an easily accessed online tool ( Benedict et al., 2014 ). Our hope is that this tool will allow us to recognize when otherwise under-reported work problems occur, serving as a signal for a clinical intervention. The initial validation of the online monitoring tool showed that both negative work events and workplace accommodations were related to neuro-performance tests ( Benedict et al., 2014 ). It is unclear whether our observations are unique to MS or are ordinary struggles of employment in the general population.

In the present paper, we compared the frequency of work problems and accommodations in employed MS patients and healthy controls, matched on demographics. We hypothesized that group differences would emerge on both clinical metrics and vocational status, and that previously observed association between work problems and clinical predictors would be replicated. Our final goal was to develop normative expectations on these vocational status indicators to help guide clinical management.

2. Materials and methods

2.1. Participants

MS patients were recruited from a tertiary MS Center in Buffalo, NY. Healthy control participants were recruited using advertisements posted in the greater Buffalo area. The sample included 138 clinically definite MS patients (107 female, 31 male), as per revised McDonald's criteria ( Polman et al., 2011 ) and 61 healthy volunteers (43 female, 18 male) between the ages of 18 and 60, who reported working more than 30 hours a week for their primary employer. Exclusionary criteria for all participants included: (a) self-employment, (b) history of developmental or learning problems, (c) previous substance dependence or current substance dependence, or (d) other medical conditions unrelated to MS that could affect cognition. MS patients were excluded if they were actively relapsing or had received steroid pulse treatment within six weeks preceding evaluation. Mean disease duration of MS patients was 9.1±7.3 years. Disease courses, as reported by patients via the online survey, were as follows: relapsing remitting (n=129, 86.2%), secondary progressive (n=4, 2.9%), relapsing progressive (n=2, 1.5%), primary progressive (n=4, 2.9%), clinically isolated syndrome (n=3, 2.2%), and unsure (n=6, 4.4%). Of the 138 patients, 132 courses were confirmed by neurologist report. There was a match between patient-reported and clinician-reported courses in 117 (84.8%) cases and mismatch in 15 (10.9%) cases. Where disagreements were found we used the clinician reported course for purpose of data analysis. All participants provided written consent as approved by the Health Sciences Institutional Review Board of the University at Buffalo.

2.2. Vocational monitoring

All participants completed a 15-min online survey, described in detail elsewhere ( Benedict et al., 2014 ), as a part of the study visit. In brief, four general areas were assessed: (a) demographics and disease characteristics, (b) self-reported symptoms as measured by the MS Neuropsychological Screening Questionnaire (MSNQ) ( Benedict et al., 2004 ), (c) general employment information (e.g. number of hours worked per week, job title, income), and (d) work-related problems and accommodations. Participants endorsed specific negative work events (e.g. formal reprimand, reduction in work hours) experienced in the past three months and were provided a list of 37 possible job accommodations to mark off if they had been receiving them at the time of survey submission. The survey also included the Patient Derived Disease Steps (PDDS), a self-assessment of physical disability based on a rating. The PDDS is highly correlated to the neurologist determined Expanded Disability Status Scale. We used the Occupational Informational Network (O*NET; www.onetonline.org) from the United States Department of Labor to characterize job types and accommodations. Specifically, occupations were categorized into one of five job zones based on how much education, related job experience, and on-the-job training is needed. Examples of occupations in Job Zone 1 (i.e. require little to no preparation) include cleaners and retail clerks, whereas examples of Job Zone 5 (i.e. require extensive preparation) include physicians and psychologists.

2.3. Clinical assessment

All participants completed a single clinical assessment. Motor function was assessed using the Timed 25 Foot Walk (T25FW) ( Schwid et al., 1997 ) and the Nine-Hole Peg Test (NHPT) ( Mathiowetz et al., 1985 ). Cognitive processing speed was measured using the oral version of the Symbol Digit Modalities Test (SDMT) ( Smith, 1982 ) and the Paced Auditory Serial Addition Test (PASAT) ( Rao, 1990 ). Verbal and visuospatial memory were measured with the California Verbal Learning Test 2nd Edition (CVLT2) ( Delis and Kramer, 2000 ) and the Brief Visuospatial Memory Test-Revised (BVMTR) (), respectively. Total learning and delayed recall measures were obtained from the CVLT2 and BVMTR. Finally the Beck Depression Inventory-Fast Screen (BDIFS) ( Benedict et al., 2003 ) was used to quantify symptoms of depression. The tests were administered by a psychologist or trained assistant under the supervision of a board certified (ABPP-CN) neuropsychologist.

2.4. Statistical analysis

All statistical analyses were performed using SPSS 22.0 (SPSS INC, Chicago, Ill). Group differences in normally distributed variables were assessed using one-way univariate analysis of variance (ANOVA). Pearson chi square tests were used to evaluate differences in categorical variables. Participants were categorized as reporting or not reporting the presence or use of negative work events and accommodations. Since the number of negative work events and number of reported accommodations are highly positively skewed, group differences were assessed using the Mann–Whitney U-test. Alpha level for all tests was set at p<0.05. The analyses were conducted comparing MS patients and controls, as well as patients with and without work related problems based on a cut-off of >1. We selected this value as a meaningful threshold based on visual inspection of preliminary data obtained from previous publications (). Effect sizes were reported using Cohen's d.

3. Results

3.1. MS versus controls

3.1.1. Participant characteristics

Demographic and health characteristics are presented in Table 1 . MS patients did not differ from controls on age, education, or Job Zone distribution. Fig. 1 illustrates the Job Zone distribution for both MS patients and controls. There was a significant group difference on years working for employer, favoring patients (F=8.42, p=0.004). Eighty-two percent of patients (n=113) reported disclosing disease status to their employer. Thirteen (21%) patients and 15 (11%) controls reported working a second job. With the additional hours of a second job, the hours worked for pay nearly differed between groups [MS: 40.6±8.6, Controls: 43.1±7.9, p=0.051]. There was no group difference in median income.

Table 1 Demographic, vocational, and clinical metrics of all MS patients and healthy controls.

Measure MS (n=138) Controls (n=61) p Value Cohen's d
Mean SD Mean SD
Age, years 44.7 10.0 43.7 12.0 0.576 0.091
Education, years 15.3 2.5 15.9 3.0 0.177 0.217
Disease duration, years 9.1 7.3
Years worked for primary employer 12.1 9.7 7.7 9.3 0.005 0.463
Motor
Timed 25 Foot Walk 5.1 2.9 4.4 1.0 <0.001 0.323
NHPT mean both hands 21.7 4.3 19.8 2.4 0.001 0.546
Cognition
CVLT2 Total Learning 54.6 10.5 58.4 10.0 0.029 0.371
CVLT2 Delayed Recall 12.2 2.8 12.8 2.7 0.1 0.218
BVMTR Total Learning 24.4 6.2 25.7 5.1 0.151 0.229
BVMTR Delayed Recall 9.4 2.2 9.9 2.0 0.091 0.238
SDMT 57.2 11.0 61.6 9.2 0.007 0.434
PASAT 46.1 11.4 48.6 10.7 0.243 0.226
BDIFS 2.3 2.7 1.0 1.6 0.001 0.586
MSNQ 20.8 11.5 14.7 7.0 <0.001 0.641

MS: multiple sclerosis; SD: standard deviation; NHPT: Nine Hole Peg Test; CVLT2: California Verbal Learning Test Second Edition; BVMTR: Brief Visuospatial Memory Test Revised; SDMT: Symbol Digit Modalities Test; PASAT: Paced Auditory Serial Addition Test; BDIFS: Beck Depression Inventory Fast Screen.

3.1.2. Motor and cognitive tests

MS patients performed worse than controls ( Table 1 ) on the T25FW, NHPT, CLVT2 Total Learning, and the SDMT, and group differences on the BVMTR Delay Recall measure neared significance. The MS group endorsed more symptoms of depression and reported more cognitive problems, as measured by the BDIFS and MSNQ, respectively. Age and sex corrected z-scores were calculated for each NP test using regression-based norms as previously published ( Parmenter et al., 2010 ). Cognitive impairment was defined as a z-score of <−2 on one test or a z-score of <−1.5 on two tests. Using this classification, 33% (n=45) of the MS participants would be considered cognitively impaired.

3.1.3. Negative work events and accommodations

The percentage of participants reporting negative work events differed by group (χ2=3.94, p=0.047) such that MS patients were more likely than controls to report negative work events (MS: 30%; Controls: 16%). Non-parametric analysis of number of problems revealed that MS patients reported more problems than controls (U=3645, p=0.049). In the MS group, 70% (n=97) reported 0 events, 19% (n=26) reported 1 event, 7% (n=10) reported 2 events, 3% (n=4) reported 3 events, and 1% (n=1) reported 5 events. In the control group, 84% (n=51) reported 0 events, 10% (n=6) reported 1 event, and 7% (n=4) reported 2 events. The proportions of participants reporting the use of accommodations also differed by group (χ2=10.05, p=0.001), such that MS patients were more likely than controls to report the presence of accommodations (MS: 48%; Controls: 23%). MS patients reported more work accommodations than controls (U=3173.5, p=0.002). The most commonly reported accommodations by MS patients were: flexible work hours (17%), the use of air conditioner or fan at work station (15%), access to refrigerator for cooling products (9%), the ability to work from home (9%), additional periodic rest breaks (9%), preferential parking (8%), and reduced physical tasks (7%).

A subsequent analysis of accommodation type followed the methods of ( Balser, 2007 ) wherein several composite groups were created from the O*NET list. The Physical Alterations accommodations included 12 modifications that could be made directly to the environment. The Assistive Technology group consisted of 11 items that are used to improve the functional capabilities of individuals with disabilities. Flexible Scheduling included ability to work at home, flexible hours, additional time to complete tasks, additional rest breaks, and individualized daily schedule. Accommodations that addressed the performance demands of the job were categorized under Modification of Demands. Cognitive accommodations included memory aids, and written job instructions. Finally, the Personal Aid category included the use of a personal assistant or a note-taker. Chi square analyses revealed group differences in the Physical Alterations variable (χ2=9.34, p=0.002), Assistive Technology (χ2=6.15, p=0.013), Flexible Scheduling (χ2=5.90, p=0.015), and Modification of Demands (χ2=4.17, p=0.041), showing that MS patients were more likely to report each type of accommodation ( Fig. 2 ).

3.2. Stable versus work-challenged MS patients

There were 15 patients who were considered work-challenged (i.e. reporting more than 1 negative work event) and 123 who were considered stable (i.e. reporting zero or one event). These subgroups did not differ on age, disease duration, hours worked per week, years of education, or Job Zone ( Table 2 ). The groups differed on reported annual income (U=391.5, p<0.001) and PDDS score (U=482.5, p=0.047). Work-challenged patients earned less money ($32,000 USD versus$48,000, respectively) and reported a higher degree of physical disability (2.0 versus 1.0 on the PDDS, respectively) than stable MS patients.

Table 2 Demographic, vocational, and clinical metrics of work-challenged and stable MS patients.

Measure Work-challenged (n=15) Stable (n=123) p Value Cohen's d
Mean SD Mean SD
Age, years 44.9 10.0 44.6 10.0 0.911 0.030
Education, years 14.7 3.2 15.3 2.4 0.328 0.212
Disease duration, years 7.2 6.5 9.4 7.4 0.280 0.315
Years worked for primary employer 10.1 8.4 12.4 9.8 0.390 0.252
Motor
Timed 25 Foot Walk 6.2 1.9 5.0 1.3 0.002 0.737
NHPT mean both hands 24.1 5.8 21.5 4.1 0.023 0.518
Cognition
CVLT2 Total Learning 50.1 9.0 55.2 10.5 0.072 0.522
CVLT2 Delayed Recall 11.3 2.9 12.3 2.9 0.167 0.345
BVMTR Total Learning 22.1 4.0 24.7 6.3 0.121 0.493
BVMTR Delayed Recall 8.0 1.9 9.5 2.2 0.011 0.730
SDMT 52.7 8.5 57.7 11.3 0.104 0.500
PASAT 40.1 13.0 47.2 10.4 0.016 0.603
BDIFS 4.8 3.8 2.0 2.4 <0.001 0.881
MSNQ 29.8 11.2 19.7 11.1 0.001 0.906

MS: multiple sclerosis; SD: standard deviation; NHPT: Nine Hole Peg Test; CVLT2: California Verbal Learning Test Second Edition; BVMTR: Brief Visuospatial Memory Test Revised; SDMT: Symbol Digit Modalities Test; PASAT: Paced Auditory Serial Addition Test; BDIFS: Beck Depression Inventory Fast Screen.

As shown in Table 2 , work-challenged patients performed worse on the T25FW, NHPT, PASAT and BVMTR Delay, and group differences on CVLT2 Total Learning neared significance. These struggling, at-risk, patients also endorsed more symptoms of depression and reported more cognitive problems than their higher functioning counterparts. There were no differences in the presence or number of any accommodations (χ2=4.07, p=0.044). However, analysis of the accommodation categories revealed that work-challenged MS patients reported cognitive accommodations more frequently than the stable MS group (χ2=4.07, p=0.044).

4. Discussion

The present study compared the frequency of negative work events in employed MS patients and healthy controls matched on demographics. Despite the fact that only employed MS patients were enrolled, a group that should have better motor and cognitive abilities than the general MS population, our patients exhibited deficits in motor function, verbal memory, and cognitive processing speed. These employed patients also reported an abnormally high number of negative work events and workplace accommodations. Secondly, neuro-performance tests differentiated patients reporting more frequent work problems versus those denying such problems. They also reported more neuropsychological symptoms and depression. Thus, while still employed, our data characterize this sub-group as being more neurologically and psychiatrically impaired, and at higher risk for job loss.

Our findings extend previous work showing that ambulation, dexterity, and cognitive function all influence the distinction between employed and unemployed patients. As noted above, this dichotomous outcome measure was employed in numerous cross-sectional studies designed to identify the clinical correlates, or predictors, of vocational disability. This approach has heuristic value but is limited is so far as the clinical goal is to identify at-risk patients and then prevent unwanted job loss. For that, assessment of more subtle work problems is needed, preferably on regular, prospective basis. We have shown that such data collection is feasible. Our data suggest a process of emerging cognitive and motor deficits, leading to increases in the negative work events, and eventually to dismissal or resignation from a position. Longitudinal work to explore this hypothesis is underway. The key is to identify those impaired patients who are nearing a threshold of marked vulnerability, and who may benefit from the support of clinicians and therapists in a position to document the impact of neurological deficit on the capacity for work, and in turn facilitate the procurement of specific workplace accommodations, or, to substantiate a claim for disability benefits.

The study yields interesting descriptive data regarding the employed MS patient in this region of the USA. Participants often disclosed their disease status to their employers and reported having a longer tenure with their employer than their healthy counterparts, regardless of job type. However, despite more seniority, the patients earned a similar income to healthy controls. Therefore, it would appear that patients are willing to sacrifice income (which should be higher with more seniority) for job security. These patients endure similar work demands yet are functioning at a significantly lower level, both physically and cognitively ( Table 1 ). Using the online vocational monitoring tool, we had endeavored to quantify work problems in MS patients compared to employed healthy persons. Our data suggest that when there are no negative work events, patients are doing well, whereas those experiencing more than one negative work event are struggling and are at-risk for job loss. As we continue to collect longitudinal data on these participants, we will be in a position to model such change statistically.

Recent work from other groups has investigated the validity of patient reported outcomes (PROs) emphasizing employment problems. The MS Work Difficulties Questionnaire (MSWDQ) ( Honan et al., 2012 ) is a 50-item test asking patients to rate from 0 (never) to 4 (almost always) the frequency of difficulties across several domains of functioning over the last four weeks. Data show that the scores generated from this test across all subscales are related to a reduction in hours worked since the diagnosis of MS. Glanz et al. (2012) have reported on a subset of 285 employed MS patients participating in the CLIMB study. In addition to the SDMT and measures of depression, fatigue and quality of life, these patients completed the Work Productivity and Activity Impairment Questionnaire, General Health Version ( Zhang et al., 2010 ). This brief scale includes six questions regarding patient perception of the impact of health problems on work efficiency. Their results showed a seemingly high level of reduced work efficiency due to health problems, although the data are difficult to interpret without a healthy control group. In general, there were robust correlations between PROs and the work productivity scale, reflecting perhaps the subjective judgment involved in rating the degree to which health status interferes with work. Our approach emphasizes concrete work events (e.g. I received a verbal reprimand) rather than judgments about overall distress or incapacity which are more likely to be confounded by depression and fatigue. We have found similar results on quality of life measures. The Sickness Impact Profile ( Bergner et al., 1981 ) which emphasizes reduction in the frequency of instrumental activities, is correlated with SDMT to a modest degree (r=−0.43) whereas there is no such correlation with the MSQOL-54. More work is needed to better understand the utility of combining these approaches, self-appraisal of work efficiency as well as clearly defined reprimands, reductions in pay, and other adverse work events.

Given the vast literature showing that cognition is strongly correlated to vocational status in MS, it is notable that the most commonly reported accommodations were related to the mobility (e.g. preferential parking) and temperature (e.g. the use of an air conditioner or fan, access to refrigerator for cooling products). We have recently shown that disclosure of diagnosis is related to T25FW and EDSS, but not neuropsychological testing ( Frndak et al., 2015 ). We propose that workplace accommodations for cognitive impairment are more difficult to understand and implement. Our data suggest that both MS patients and controls use cognitive accommodations equally often, suggesting that all persons benefit from external aids designed to improve mental efficiency.

There are important limitations to the current study. We have not yet collected sufficient longitudinal data that will enable us to determine clinical correlates of worsening on the online monitoring tool. For now, we are left with this cross-sectional analysis. Also, while the questions posed emphasize events and require little subjective judgment, they are nevertheless reported by patients and healthy volunteers. We did not have confirmation from proxies, such as co-workers or employers.

The present study provides additional support for the use of the online vocational monitoring tool in MS. Compared to control subjects, full-time employed MS patients performed more poorly on tests of verbal memory and processing speed and were more likely to report negative work events and workplace accommodations. Consistent with other reports, work-challenged MS patients exhibit poorer dexterity, and visuospatial memory, and processing speed than those who are stable. Future research should aim to expand on these findings and identify how key clinical and vocational measures change over time in an effort to understand what actions can be taken by clinicians and patients alike to prolong employment in MS.

Funding

This research was partially supported by the Advancing Research in Multiple Sclerosis coalition in Buffalo, NY, and Novartis.

Conflicts of interest

RHB Benedict serves on advisory boards or provides consultancies for Biogen Idec, Novartis, Genzyme, Genentech, and he receives research support from Biogen Idec, Accorda, Questcor, Novartis, and Genzyme.

B Weinstock-Guttman has received speaking and consultant fees from Biogen Idec, Teva Neurosciences, EMD Serono, Pfizer, Novartis, Genzyme, and Accorda. She has also received grant/research support from Biogen Idec, Teva Neurosciences, EMD Serono, Pfizer, Novartis, Accorda, ITN, Questcor, and Shire.

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Footnotes

Department of Neurology, University at Buffalo, State University of New York (SUNY), Buffalo, NY, USA

Corresponding author.

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• Dr Rebecca Farber

Rebecca Farber, MD is an attending neurologist and assistant professor of neurology at the Neurological Institute, Columbia University, in New...

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