Employment issues and vocational rehabilitation considerations for people with Parkinson’s disease: A review of the literature and a call to action

Abstract

BACKGROUND:

Parkinson’s disease (PD) is a chronic, degenerative, neurologic condition affecting the central nervous system. The increasing prevalence of PD combined with the increasing economic need among older Americans to work later in life make employment an increasingly important topic of investigation.

OBJECTIVE:

The purpose of this investigation is to examine the prevalence of articles in the literature addressing the association between PD and employment.

METHODS:

A literature review was conducted on peer-reviewed articles from 2000–2015 on PD and employment issues.

RESULTS:

Although PD is the second most common neurodegenerative disorder and results in numerous sequalae that may negatively affect employment, very few articles specifically address this association. Moreover, PD has been and remains largely absent from the rehabilitation counseling literature. One possible explanation for this may that the typical age at diagnosis is 62 years-old. The literature clearly suggests that the number of Americans working past 65 is steadily increasing, which indicates that individuals with PD may still want and/or need to work. Rehabilitation counselors are uniquely qualified to provide holistic services to individuals with disabilities and provide guidance and support to assist them in gaining or maintaining their employment goals.

CONCLUSIONS:

PD is an increasingly prevalent chronic condition with roughly 60,000 new diagnoses annually, and the time has come that the rehabilitation counseling profession begin to address the challenges and consider opportunities for effective interventions.

Keywords

Parkinson’s disease employment neurodegenerative rehabilitation counseling

1 Introduction

Parkinson’s disease (PD) is a chronic, degenerative, neurologic condition affecting the central nervous system. It is typically diagnosed late in life and can negatively affect a number of life domains. PD is the world’s second most common neurodegenerative disorder behind only Alzheimer’s disease (Jankovic, 2012). The prevalence of PD in the United States (US) is roughly 1 million, with worldwide rates ranging from 7 to 10 million (Parkinson’s Disease Foundation [PDF], 2017). Moreover, nearly 60,000 new cases of PD are reported annually in the US alone (National Institutes of Health – Senior Health [NIH], 2016). The incidence rate of PD is increasing significantly as life expectancy has increased and as the 77 million members of the American Baby Boom Generation continue to approach retirement age (Goldman & Tanner, 2015). The number of individuals with PD is expected to double by 2030 (Dorsey et al., 2007), and the current disease-related costs in the United States of $14 to $23 billion are projected to increase to $50 billion by 2040 (Kowal, Dall, Chakrabarti, Storm, & Jain, 2013). One of the explanations given for the dramatic rise in both PD prevalence and projected costs is the relative growth of the aging population. According to the National Parkinson Foundation (NPF, 2017), the mean age of onset of PD is 62, with increasing prevalence as the population ages. Early-onset Parkinson’s disease (EOPD), however, affects individuals between 21 and 55 years (Quinn, Critchley, & Marsden, 1987; Schrag & Schott, 2006). Although the number of individuals diagnosed with EOPD represent a much smaller proportion of the total population (about 10% of all PD diagnoses), the impact is no less significant.

PD is typically associated with individuals who are older, frequently diagnosed at the pinnacle of their careers. The limited research on PD and employment suggests that individuals with PD leave the workforce earlier than their non-disabled peers; however, the issues and barriers to employment maintenance faced by people with PD are not well understood. Accurate and comprehensive understanding of these barriers is necessary for effective rehabilitation. This understanding is becoming increasingly important in the context of the current trend toward older Americans staying in the workforce longer and until later in life, frequently due to economic necessity. The Bureau of Labor Statistics (BLS, 2013) reports that the percentage of Americans ages 65–74 in the workforce is expected to rise to 31.9% by 2022, significantly higher than the 26.8% in 2012. Moreover, the number of Americans 65 years of age and older in the labor force in January of 2006 was roughly 5.2 million, but in January 2016 the number had increased by more than 65% to approximately 8.5 million (BLS, 2017).

The increasing prevalence of PD combined with the increasing economic need among older Americans to work later in life make employment an increasingly important topic of investigation. Unfortunately, likely due to the (typical) older age of persons with PD, the employment barriers facing persons with PD have historically received little attention. This issue has been compounded by the fact that employment retention has not been identified as a priority among health professionals (Banks & Lawrence, 2006). Although there is limited research addressing PD and employment, there appears to be a desire among individuals with PD to continue working.

The broad purpose of this study was to explore the current and potential role of rehabilitation counseling in understanding and addressing the employment situation among individuals with PD. Because the impact of PD on employment is not the result of any single factor, but results from a variety of physical, emotional, psychological, and environmental factors, a fuller understanding of the employment barriers faced by people with PD requires an understanding of the disease process and treatment. A brief overview of PD is provided below. This is followed by a discussion of the specific purposes of this study and the research questions addressed.

2 Disease overview

PD is a chronic, degenerative, neurological condition classically defined as a disorder of movement (Pearce & Jones, 1994). PD was first described nearly two centuries ago by English physician James Parkinson, and, although significant progress has been made in etiology and treatment, conceptualization of the disease continues to evolve (Kalia & Lang, 2015). Although the exact etiology of PD remains elusive, the death of dopaminergic neurons in the substantia nigra pars compacta from both genetic and environmental mechanisms is the most well documented explanation (Przedborski, 2015). The loss of the dopaminergic neurons in the nigrastriatal pathway and the accumulation of eosinophilic intracytoplasmic proteins called Lewy bodies are considered to be the pathologic hallmarks of PD (Brockman & Gasser, 2015). These changes, particularly relating to dopamine loss, result in the common presenting motor features of resting tremor, bradykinesia, rigidity, and postural instability (Fahn & Predborski, 2005). Because there are no diagnostic tests allowing for a definitive diagnosis of PD, diagnosis is typically achieved through routine neurologic examination and the evaluation of stiffness, slowness, and tremor at rest.

The cardinal motor features of PD are typically responsible for the patient seeking medical care, but, by the time patients become symptomatic, the majority (60% ) of dopaminergic neural function has already been lost, and the actual onset of PD generally predates the motor manifestation by approximately 4.5 years (Moeller & Eidelberg, 1997). Because PD is classified as a movement disorder, the most commonly described manifestations are motor in nature. However, during the 21^st century, increased attention has been paid to the non-motor features of PD (Sauerbier & Chaudhuri, 2015). Non-motor symptoms are considered a key determinant of both the individual with PD and his/her caregiver’s overall quality of life and social functioning and, as such, may present the most significant challenges to clinicians (Stern, Lang, & Poewe, 2012). A PD patient experiences an average of 8 to 13 non-motor symptoms even at early stages of the disease (Chaudhuri et al., 2006).

Many of the non-motor effects of PD present after diagnosis and are frequently associated with medication side-effects. However, there are a number of non-motor features that are often present well before the onset of the motor dysfunction and diagnosis. Among the earliest non-motor symptoms that appear, often up to 10 years before the motor manifestations, are loss of the sense of smell, constipation, and sleep disturbances (Stacy, 2011). These non-motor features are frequently attributed to other causes, but, following the presentation of motor symptoms, they contribute to the PD diagnosis. Other non-motor effects of PD can include dysfunction in many body systems such as psychosis (60%; Riedel et al., 2010), urogenital dysfunction (38% – 71%; Ransmayr et al., 2008), orthostatic hypotension(10% – 20%; Stacy, 2011), vision and sensory decline, dementia (30%; Biggins et al., 1992), impaired executive functioning, depression (17% – 22%; Reijnders, Ehrt, Weber, Aarsland, & Leentjens, 2008), anxiety (40%; Dell’Angnello et al., 2001), impulsivity (17.5%; Antonini et al., 2011), and pain (Alder, 2005; Barbas, 2006; Stacy, 2011).

PD is an increasingly prevalent, chronic, and debilitating condition that presents numerous challenges to those affected. Although there is no cure available for PD, there are a number of available treatment options aimed at decreasing the most bothersome symptoms. The most commonly used pharmacologic agent to treat the motor symptoms of PD is the levodopa/carbidopa combination. Levodopa is metabolized into dopamine in the brain, and Carbidopa serves a dual function of preventing the breakdown of Levodopa in the bloodstream and increasing bioavailability while reducing the nausea and vomiting associated with higher doses of Levodopa. Additionally, there are a number of effective agents (e.g., dopamine agonists, anticholinergics) that are used to treat PD and its symptoms.

3 Role of rehabilitation counseling

PD is a chronic illness that can significantly affect quality of life. Although a neurologist is typically responsible for the initial treatment of the motor symptoms of PD, the non-motor features may necessitate the involvement of various additional professionals. Rehabilitation counselors (RCs) are well trained to address the vocational and psychosocial aspects of PD. Both the motor and non-motor features of PD likely result in decreases in activities associated with quality of life (e.g., employment, social interactions), and RCs have the knowledge and skills to assist individuals in achieving positive quality of life outcomes. Due to the growing prevalence of PD and the increasing age of the average American worker, RCs will be increasingly likely to work with people with PD in public vocational rehabilitation (VR) and other service delivery settings.

Unfortunately, there is virtually no information on rehabilitation counseling with people with PD, nor is there a clear understanding of what their needs are and how to most effectively meet them. One of the most widely accepted means of disseminating information and best practices is through peer-reviewed professional publications (Plotner, Shogren, & Strauser, 2011; Williams & Buboltz, 1999). The purpose of this study was to conduct a review of the rehabilitation counseling literature to identify articles published on PD in order to (a) identify the extent to which RCs work with individuals with PD, (b) illuminate best rehabilitation counseling practices, and (c) prepare a foundation for the inclusion of PD in the rehabilitation counseling research literature. The following research questions were addressed:

What is the prevalence of articles addressing PD and employment in the literature in general between 2000 and 2015?

What is the prevalence of articles addressing PD and employment in the rehabilitation counseling literature specifically?

What areas need to be addressed in future research?

4 Method

The procedure for both journal and article inclusion is described below. I conducted a search of the articles published on PD and employment between 2000 and 2015 using EBSCOhost and PubMed electronic databases and the key words Parkinson’s disease, PD, employment, and work. Only full-length, peer-reviewed articles (e.g., research studies, literature reviews, program descriptions, opinion-based/position statements) with abstracts were included for analysis. The article titles and abstracts were reviewed to ensure that each article was specific to PD and employment.

I then chose to assess the number of articles that have been published in rehabilitation counseling journals for the same period, using the same criteria. I began by identifying the most relevant and frequently read journals in rehabilitation counseling. The selection of rehabilitation counseling journals was based on previous research and publications (Kettaneh, Kinyanjui, Slevin, Slevin, & Harley, 2015; Plotner, Shogren, & Strauser, 2011) and included: Journal of Applied Rehabilitation Counseling, Journal of Rehabilitation, Journal of Vocational Rehabilitation, Rehabilitation Counseling Bulletin, and Rehabilitation Research, Policy, and Education.

5 Results

The search of the all-inclusive research on PD and employment (Research Question 1) yielded a total of 84 articles - nine from EBSCOhost and 75 from PubMed. Of the 84 articles, nine were duplicates, so 75 were retained to be reviewed for appropriateness. 13 articles were determined to fit the inclusion criterion of specifically addressing the association between PD and employment. There were two articles from Disability and Rehabilitation, four in Movement Disorders, and one each from the Journal of Rehabilitation Medicine, Work, Acta Neurologica Scandinavia, Parkinsonism and Related Disorders, and the Irish Journal of Medical Science. In the subsequent search of rehabilitation counseling journals (Research Question 2), there were only three articles that mentioned PD, along with other chronic conditions, and none that assessed the relationship between PD and employment.

6 Discussion

The evaluation of the literature underscores the paucity of research regarding PD and employment. In particular, the lack of published articles in top rehabilitation counseling journals is troubling, especially considering the number of individuals with PD who may desire to remain competitively employed even as the disease progresses. Although PD typically occurs in older age, nearly 30% of individuals are diagnosed before the age of 65, and a significant number of them are affected in their 30 s (Gustafsson, Nordstrom, Strahle, & Nordstrom, 2015). Individuals who are diagnosed with PD at younger ages experience challenges that are different from those faced by older individuals (e.g., increased dependency, marital difficulties, increased financial strain), which means that the impact of PD is likely to differ by age at diagnosis (Schrag, Hovris, Morley, Quinn, & Jahanshahi, 2003). Regardless of the age of onset, however, most adults value employment because of the irreplaceable benefits of self-esteem, autonomy, social contact, and life satisfaction (Eklund, Hansson, & Ahlquist, 2004; Hergenrather, Rhodes, McDaniel, & Brown, 2003).

The limited available research consistently suggests that many individuals with PD leave their jobs prior to typical retirement age due to disease symptoms (Martikainen, Luukkaala, & Marttila, 2006; Murphy, Tubridy, Kevelighan, & O’Riordan, 2013; Schrag & Banks, 2006; Schrag et al., 2003). Among the factors contributing to leaving work early are motor symptoms, fatigue, anxiety, stress intolerance, and depression (Gustafsson et al., 2015; Martikainen et al., 2006; Murphy et al., 2013; Timpka et al., 2016). Unfortunately, fear of stigma and discrimination may result in individuals not approaching employers with requests for reasonable accommodations (Banks & Lawrence, 2006; Murphy et al., 2013; Martikainen et al., 2006). According to Armstrong and colleagues (2014), who prospectively followed people with PD to evaluate features of the disease that predict early exit from work, mental health factors (e.g., depression, anxiety) had a greater impact than did motor symptoms.

Studies conducted in the United States and around the world reveal that the average time between diagnosis and leaving employment for individuals with PD ranges from 2 years to 10 years (Cholewa, Gorzkowska, Kunicki, Stanula, & Cholewa, 2016; Martikainen et al., 2006; Murphy et al., 2013; Schrag et al., 2003). Although PD is a progressive condition, it affects each individual differently, which may account for the disparity in study results.

The limited research on PD and employment appears to consistently agree on several issues: (a) individuals with PD leave the workforce earlier than non-disabled workers, (b) they usually retire in the first 10-years post diagnosis, and (c) the reasons for leaving work are multifactorial (e.g., motor- and non-motor symptoms). In one of the only studies to assess whether individuals with PD desire to continue working, Murphy et al. (2013) reported that 82% were unhappy following cessation of work. Among individuals with early onset PD, literature from the late 1980s (Parkinson’s Study Group, 1989) indicated that 49% wanted to work as long as possible, but little contemporary attention has been paid to this issue. This percentage is similar to what has been described regarding employment among individuals with multiple sclerosis (MS). Specifically, among unemployed people with MS, 75% left their jobs voluntarily, often before their symptoms made them incapable of working (Roessler, Rumrill, & Hennessey, 2002). Further, 80% of people who become unemployed following their diagnosis with MS report that they retain the ability to work, and up to 75% report that they would like to return to work (Julian, Vella, Vollmer, Hadjimichael, & Mohr, 2008; Rumrill, Hennessey, & Nissen, 2008; Sumner, 1997). It is likely that the situation is similar among people with PD, although considerably less research attention has focused on this population.

The literature proposes several potential facilitators in relation to workforce participation among people with PD. Support received from one’s employer (e.g., shorter working hours, increased flexibility, change in duties) has been identified as particularly important to job retention (Gustafsson et al., 2015; Martikainen et al., 2006; Schrag & Banks, 2006). Specifically, Banks and Lawrence (2006), in a study conducted in the U.K., noted that individuals with PD who have supportive employers “worked significantly longer post-diagnosis than those who reported that their employer had not been supportive” (p. 22). Unfortunately, not all employers support employees with disabilities, due to factors such as the (perceived) high costs of workplace accommodations, negative attitudes toward people with disabilities, and a lack of awareness of information regarding effective workplace supports. Conversely, factors that appear to facilitate positive employment outcomes for individuals with PD include: (a) high levels of motivation on the part of the worker (Martikainen et al.), (b) a more positive attitude on the part of the worker and the employer (Banks & Lawrence; Cholewa et al., 2016; Schrag & Banks), and (c) a feeling of empowerment on the part of the worker (Banks & Lawrence). In fact, one’s level of support from his or her employer may, by itself, be insufficient to positively affect outcomes; individuals “with progressive conditions need to be empowered to make ‘optimum’ decisions regarding continued employment” (Banks & Lawrence, p. 23). As evidenced by the positive psychology movement, individuals who are made to feel empowered and possess a positive attitude achieve more favorable outcomes.

7 Rehabilitation counseling implications

Published guidelines for the management of PD recommend that “adaptations can often be made... and changes in job requirements, number of work hours, or workplace environment, in an effort to prevent the need for premature termination or retirement” (Olanow, Watts, & Koller, 2001, p. S71). Further, VR counselors are uniquely qualified to assist in developing workplace supports, job flexibility, workplace accommodations, and maintenance services (Strauser, 2013). Considering that a number of the non-motor features identified as being associated with leaving the workforce (e.g., anxiety, depression, negativity) are largely amenable to counseling interventions, rehabilitation counselors may be uniquely qualified to offer assistance.

Unfortunately, little is known about the barriers and facilitators to employment for individuals with PD, and even less is understood about the interventions that may provide positive employment outcomes. VR counselors have a broad skill set for working with clients on a wide array of issues relating to successful employment, but there is no data addressing how VR might improve outcomes for individuals with PD. That said, Cichy and Leslie (2017, p. 119), espouse that rehabilitation counselors need to familiarize themselves “with the medical and psychosocial aspects of age-related emerging disabilities” like PD. The contemporary RC literature provides nothing with regard to PD and employment, but the limited research in other sources provides a starting point for identifying promising VR practices. Although there is currently no information about individuals with PD being represented in VR programs, gaining an understanding of the VR interventions that lead to employment success for people with PD is an important objective for future rehabilitation research investigations.

8 Conclusion

Parkinson’s disease, although well represented in the medical literature, is largely unaddressed in the rehabilitation counseling literature. More specifically, there is an overall paucity of literature addressing what the facilitators and barriers are for employment among individuals with PD. Unfortunately, this leaves VR professionals unaware of how to best address the psychosocial and vocational needs of Americans with PD. It is likely that individuals with PD can benefit from the same services offered to other VR consumers (e.g., counseling, employer consultation, accommodations, job carving, education), but more research is needed to determine if this is the case. Specifically, future RC research should address the following questions: (a) Do individuals with PD wish to continue their employment; (b) If so, what are the specific factors that may increase the likelihood of maintaining employment; (c) What employment barriers faced by individuals with PD are modifiable with appropriate VR interventions; and (d) What are the needs of employers relating to employees with PD? Answers to these questions will enable RC and VR professionals to provide responsive and effective employment-related services to people with PD, who have established themselves as an emerging rehabilitation clientele.

Conflict of interest

None to report.

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