The focus of this chapter is on selected issues that affect people with disabilities across all types of medical conditions. These issues include the approach to pain and pain treatment, comorbidities and disability recovery, and variation in the availability and use of effective treatments.
Chronic pain has been linked to numerous physical and mental health conditions and contributes to high health care costs and lost productivity. It is one of the most common reasons that adults seek medical care and has been linked to restrictions in mobility and daily activities, dependence on opioids, anxiety and depression, and poor perceived health. Updated population estimates from the National Health Interview Survey indicate that 50 million (20.4 percent) U.S. adults had chronic pain and 19.6 million (8.0 percent) had high-impact chronic pain in 2016. Both conditions were more prevalent among adults living in poverty, adults with less than a high school education, and adults with public health insurance (Dahlhamer et al., 2018).
Chronic pain is defined as pain that persists or recurs for 3 to 6 months or longer. It is frequently associated with disability, although many people with chronic pain live without disability. The National Pain Strategy, issued by the U.S. Department of Health and Human Services in 2016, emphasized the importance of differentiating between people with and without functionally limiting pain and defined “high-impact chronic pain” as pain associated with a restriction of participation in work, social, or self-care
activities (IPRCC, 2016). Modern conceptualizations of chronic pain recognize that pain can be a symptom of an underlying health condition or a primary condition in itself and that interacting biologic, psychologic, and social factors contribute to the etiology, clinical course, and functional outcomes of all chronic pain conditions, regardless of their primary or secondary nature (IOM, 2011). That understanding is consistent with research findings that the experience of pain is highly variable among persons with similar anatomical findings or disease severity, even in well-described chronic pain conditions.
A systematic classification of chronic pain developed by the International Association for the Study of Pain and implemented by the World Health Organization in the International Classification of Diseases, 11th Revision (ICD-11) recognizes both primary and secondary chronic pain syndromes (Treede et al., 2019). According to that report, the new ICD category for chronic pain comprises the most common clinically relevant disorders, which were divided into seven groups: chronic primary pain, chronic cancer pain, chronic posttraumatic and post-surgical pain, chronic neuropathic pain, chronic headache and orofacial pain, chronic visceral pain, and chronic musculoskeletal pain. Regardless of the etiology, chronic pain is a major source of emotional distress and functional disability (Nicholas et al., 2019). Chronic secondary pain syndromes are defined by an underlying disease or injury that is considered to be the cause of the pain (although the secondary pain syndrome may persist beyond the resolution of the inciting disease or injury).
Chronic primary and secondary pain conditions are relevant to all sections of this report. In common musculoskeletal conditions, including chronic primary back pain and chronic secondary musculoskeletal pain due to inflammatory disease or structural abnormalities, chronic pain is the major driver of functional impairment and disability. In cancer, chronic pain arising from the disease process or from the adverse effects of cancer treatment contributes substantially to the functional impairment and disability experienced by cancer survivors. Finally, common mental health conditions and pain conditions are frequently comorbid, with bidirectional associations and, potentially, shared central nervous system mechanisms. For example, chronic pain and depression appear to have mutual adverse influences on each other, so the presence of both conditions together is associated with greater disability than either condition alone.
The treatment of chronic pain includes therapies aimed at the underlying cause of pain (when applicable), therapies aimed at alleviating symptoms, and therapies that address factors involved in determining the course of pain and associated impairments. Biomedical approaches that focus on removing specific underlying causes of pain, such as surgery to correct anatomical abnormalities, often fail to resolve secondary pain syndromes
and their associated impairments. Likewise, approaches that are narrowly focused on relieving symptoms, such as analgesic medications, often fail to restore functioning or provide long-term pain relief. Specifically, in chronic pain, opioid analgesics lack demonstrated advantages over other treatments and are associated with increased disability and reduced functional recovery; although they are commonly prescribed, opioids are not recommended by chronic pain guidelines. Current guidelines for common chronic pain conditions (e.g., low back pain) recommend active non-drug approaches such as exercise and behavioral therapies as core treatments. Unfortunately, individual therapies for chronic pain result in meaningful improvement for only a subset of patients, and active approaches require sustained patient effort over time to achieve optimal results. For many patients with high-impact chronic pain, the best treatment approach is multimodal integrated care that combines different types of therapeutic approaches to address medical, psychologic, and social factors in a coordinated and supportive fashion (IOM, 2011; IPRCC, 2016).
Comorbidity, also known as multimorbidity, is defined as the coexistence of more than one distinct condition or disease in an individual (Valderas et al., 2009). Having multiple chronic medical conditions affects a range of medical outcomes, including mortality, health-related quality of life, and functioning (Fortin et al., 2007). Negative outcomes related to comorbidity occur beyond what would be expected from the summed effect of single conditions, as chronic diseases tend to interact with each other in such a way that leads to new clinical presentations (Vetrano et al., 2018). There is increasing evidence that the comorbidities prevalent with primary diagnoses have a significant impact on return to work after disability. The committee that produced a recent National Academies consensus study on functional assessments for adults with disabilities acknowledged that the presence of multiple impairments and comorbidities can further impair functioning (NASEM, 2019). Therefore, it is necessary to consider that when assessing an individual’s ability to sustain work on a regular and continuing basis, a person’s capacity to work may be overestimated if, for example, a psychologic comorbidity is present.
Research suggests that the most important comorbidities affecting functionality and work-related disabilities involve mental health conditions co-occurring with other psychologic disorders or with physical conditions (Greenberg et al., 2015; Kessler, 2003). Symptoms associated with diagnoses such as depression and anxiety can affect a person’s ability to manage one or more limitations in a work setting. For individuals with a wide range of physical and mental impairments, depression is the most
common comorbidity limiting employment as well as rehabilitation from other events (NASEM, 2019). For many conditions that result in disability, co-occurring depression is frequent and is associated with poor outcomes. It is often unrecognized both as a primary diagnosis and as a powerful contributor to impairment from other diagnoses. The impact of treatment is clear when depression is the central diagnosis, but less is known about how to identify and address it as a complicating factor (Anderson et al., 2015; Scaratti et al., 2017; Sullivan et al., 1997).
The combined effects of mental health disorders, such as depression, and physical health disorders significantly affect work-related disability (Kessler and Frank, 1997; Rystälä et al., 2005). Data from a major mental health survey found that all physical disorders, except injury caused by accident, were significantly related to anxiety and mood disorders (Buist-Bouwman et al., 2005). Both physical and mental health disorders were significantly related to work loss, and the physical–mental health comorbidity was largely additive except for chronic back pain and hypertension, which interacted with mental health disorders synergistically. Thus, interactions between comorbidities complicate recovery. While mental health disorders exacerbate other conditions, physical comorbid conditions will increase both the likelihood of mental health-related disability and the extent of the work impairment. Without treating all of the conditions, the overall work-related disability is unlikely to be reduced.
Comorbidities, including clinical depression and anxiety (Bodurka-Bevers et al., 2000), are also common among individuals with cancer, and those with comorbidities experience poorer survival, poorer quality of life, and higher health care costs (Sarfati et al., 2016). While it has been well documented that comorbidities are common among adults over the age of 65 with cancer (Williams et al., 2016), a growing body of literature suggests that comorbid conditions such as depression, anxiety, asthma, high cholesterol, and hypertension result in a high burden in young adults with cancer, particularly those aged 15–39 (Smitherman et al., 2018). Young adults with cancer are more likely than their cancer-free peers to be frail and to experience a high level of comorbidities, a phenomenon known as accelerated aging (Smitherman et al., 2018). Cancers share many risk factors with comorbid conditions, such as older age, smoking, poor diet, obesity, and alcohol abuse (Sarfati et al., 2016; Sarna et al., 2002). Additionally, the biologic mechanisms associated with comorbid conditions may predispose an individual to cancer. Comorbidities can be caused by the toxicities of chemotherapy. A study by Chao et al. (2018) found that in a cohort of 6,778 cancer survivors aged 15–39, chemotherapy exposure was associated with multiple comorbidities.
While most studies addressing factors related to return to work are disease specific, a single “review of reviews” across multiple studies of
common mental health disorders, cardiovascular disease, and cancer identified six barriers related to a patient’s ability to return to work. These were anxiety, depression, job strain, other comorbidities, older age, and low education (Gragnano et al., 2018). The common factors identified here support the validity of a cross-disease approach when addressing recovery and return-to-work interventions. The identification and treatment of co- and multimorbidities along with primary diagnoses may improve functional outcomes and the ability to return to work in patients receiving disability compensation.
While the committee understands that the Social Security Administration (SSA) did not intend for this report to discuss access to treatment, a brief discussion on variation in the availability and use of effective treatment helps illustrate the complexity of the relationship between available treatments and health outcomes. There can be enormous variations in many aspects of health care delivery that are not explained by medical need or patient preference. Furthermore, millions of Americans with long-lasting medical conditions do not receive effective care (IOM, 2001; Wennberg, 2011). Consistent with past Institute of Medicine reports (IOM, 2001, 2006), the committee defines effective care as care that is based on scientific knowledge and that includes providing services to those who might benefit while avoiding overuse and underuse. The factors that influence the availability and use of effective care are complex and include the characteristics of the interventions (e.g., costs and complexity), the characteristics of the individuals (e.g., income, insurance, culture, and health literacy), health care providers (e.g., knowledge and beliefs), the health care system (e.g., staffing, wait times, incentives), and communities (e.g., rurality, transportation availability, social supports) as well as the information available through the media, policy, and regulations.
Noted disparities exist in cancer screening, treatment, and outcomes by sociodemographic characteristics (including race and ethnicity), income, employment status, and geographic area (Du et al., 2011; Forrest et al., 2013; Singh and Jamal, 2017; Wheeler et al., 2013). One major barrier to care is a lack of insurance or underinsurance. Cancer treatment is expensive, and its cost may be a barrier to the most effective treatment (Banegas et al., 2016, 2018; Yabroff et al., 2016). Geographic barriers to cancer treatment also exist, including the lack in some areas of a geographically accessible supply of providers (Ambroggi et al., 2015; Dragun et al., 2011; Jacobsen, 2017; Lin et al., 2015). Oncology centers, particularly the most advanced, are geographically skewed and not often located in rural areas
(Dragun et al., 2011). People who live farther from effective care are less likely to receive it (Jacobsen et al., 2017; Lin et al., 2015). Previously disabled persons also have lower treatment rates (Iezzoni et al., 2008). The availability of nonmedical treatments that affect recovery from cancer, such as social supports, job retention programs, and employment accommodations, also vary by income level, geographic area, education, culture, race and ethnicity, gender, and other factors (Mustian et al., 2017). Among the population of individuals who would qualify for Social Security Disability Insurance on the basis of a cancer diagnosis, there is known variation in the availability of evidence-based and effective cancer treatments (Jacobsen et al., 2017; Mougalian et al., 2015; Murphy et al., 2016; Shalowitz et al., 2015; Shugarman et al., 2009). Some disparities in treatment in this population stem from differences in the stage at diagnosis and in comorbidities at diagnosis (Iezzoni et al., 2008; Yang et al., 2010). Others, however, stem from nonmedical factors, including income, geography, and insurance (or uninsured status).
For many cancers, an effective treatment, while causing remission in the diagnosed cancer, is the cause of subsequent disability due to the side effects of treatment, which can include fatigue, depression, pain, and the loss of physical and cognitive function (Jones et al., 2016; Mustian et al., 2017). People with better access to such cancer screening services as mammography, colorectal screening, and Pap smear tests—or who simply have more frequent contacts with the medical care system—might be diagnosed at an earlier stage and thus avoid both subsequent cancer-related disability and death (Hall et al., 2018; Joseph et al., 2012; White et al., 2017). However, an interesting dynamic appears when patients with better access to screening, early cancer interventions, or effective treatments for later-stage disease may end up with longer periods of disability due to the disabling side effects of effective treatment.
Mental health disorders affect about one in five Americans (IOM, 2015; Kessler et al., 2005). Fortunately, there are effective psychosocial and pharmacologic treatments, and evidence continues to accumulate for new interventions. However, not all individuals with mental health disorders receive high-quality mental health care and have the opportunity to benefit from treatment. Two problems impede clinically meaningful improvement among individuals with mental health disorders: no care (Kessler et al., 2005; Mojtabai et al., 2011) and, among those who do receive health services, poor care (e.g., IOM, 2006, 2015). The structural barriers to receiving needed care are further complicated by poor insurance coverage for mental health disorders, the separation of mental health from other medical care (IOM, 2006), and significant limitations in the availability of skilled specialty mental health providers in remote geographic areas (President’s New Freedom Commission on Mental Health, 2003). Shame, stigma, and
discrimination further impede individuals from recognizing they have a problem and seeking treatment for mental health disorders (IOM, 2006).
Even if individuals overcome the barriers and seek mental health treatment, they may not receive evidence-based care and therefore may experience minimal benefit, no benefit, or even harm from the health services they received. The lack of availability of evidence-based mental health services is a known problem (Bauer, 2002; IOM, 2006, 2015; Simon et al., 2001; Stein et al., 2004), and consumers often do not have a way of judging the quality of the mental health care they do receive. An additional concern is that some treatments are not only ineffective but may be unsafe and have risks that outweigh any potential short-term benefit (see, e.g., Guina et al., 2015). Gaps in provider training (Weissman et al., 2006), a broad array of mental health provider specialty types, the fragmentation in care, the lack of high-quality monitoring systems and decision support tools, and other individual, organizational, and system level factors all contribute to the problem of ineffective care for mental health disorders (Aarons et al., 2012; IOM, 2006, 2015).
Musculoskeletal disorders are among the most prevalent and disabling conditions in adults (USBJI, 2014). The problem of unwanted variation in and ineffective treatment of musculoskeletal conditions is well known (e.g., Brand et al., 2013; Foster, 2018; Skinner et al., 2003). People often have multiple musculoskeletal disorders simultaneously and are likely to experience pain as part of the condition. Low back pain is the most frequently reported musculoskeletal disorder (IOM, 2011; USBJI, 2014; Woolf and Pfleger, 2003). Individuals with musculoskeletal disorders often experience barriers to adequate pain treatment (Becker et al., 2017; IOM, 2011). Additionally, policies on coverage and reimbursement often encourage the choice of pharmacologic treatment over evidence-based psychosocial or comprehensive approaches that integrate pharmacologic and non-pharmacologic approaches (Heyward et al., 2018; Lin et al., 2018). Chronic musculoskeletal pain is the most common target of opioid therapy despite its unfavorable risk–benefit profile (although that situation is likely changing), and it has contributed to prescription opioid use disorder and overdose deaths (CDC, 2018).
The considerable variability in the availability and use of effective health care for cancers, mental health disorders, and musculoskeletal disorders has implications for this report. In particular, because nonmedical factors contribute to the types and quantity of treatments that patients receive, information about treatments cannot be used to reliably evaluate the severity of a medical condition. SSA previously asked the National Academies to examine the association between health care utilization and impairment severity. Cancers, mental health disorders, and musculoskeletal disorders as well as other conditions were included in that analysis.
The resulting report, Health-Care Utilization as a Proxy in Disability Determination, concluded that there was “no evidence that health-care utilizations alone can predict disability, impairment severity, or disease severity” (NASEM, 2018, p. 9). However, experts on this committee believe that there may be instances when the use of certain treatments for select cancers, musculoskeletal disorders, or mental health disorders might serve as an indicator of severity. Such instances are explicitly discussed in the relevant chapters.
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