How Does Health Impact Challenging Behavior?

Abstract

People with severe disabilities have a higher prevalence of many health conditions when compared with the general population. Examples include gastrointestinal conditions, chronic allergies, epilepsy, and sleep dysregulation, among many other health concerns. Of particular interest in the treatment of challenging behavior is the comorbidity of health conditions and behavioral challenges. Evidence suggests that not only do people with severe disabilities have higher rates of health conditions, but people with severe disabilities and challenging behavior have even higher rates of health concerns. This article reviews the existing evidence linking health conditions and challenging behavior, discusses health disparities in diagnosis and treatment of these comorbidities, and suggests future avenues for discovery and intervention.

Keywords

severe disabilities neurodevelopmental disabilities challenging behavior health conditions comorbidity

Health is a critical element in defining our quality of life. In general, the healthier we are, the more we enjoy satisfactory social relationships, employment, and daily life (Barbotte et al., 2001; Wilson & Cleary, 1995). As Mahatma Gandhi once observed, “It is health that is real wealth and not pieces of gold and silver” (Somoskövi et al., 2013, p. 437). Despite the importance of personal health, research evidence is accumulating showing that people with severe disabilities have a higher prevalence of health conditions when compared with the general population. And, there is also a growing body of research linking certain health conditions with increased instances of challenging behavior for people with severe disabilities.

Overall, people with severe disabilities experience a similar range of health conditions when compared with the general population, but exhibit a higher prevalence of health conditions in specific areas, apart from syndromic etiologies (King-Dowling et al., 2019). In addition, the occurrence of health conditions increases at a greater rate over time for people with neurodevelopmental disabilities (Doshi-Velez et al., 2019). In sum, people with severe disabilities are sicker than most other groups of people and experience more illnesses as they age.

Specific types of heath conditions have been identified that occur at high rates in people with severe disabilities. These include gastrointestinal disorders, immune system disorders, and central nervous system comorbidities (e.g., Kohane et al., 2012; Muskens et al., 2017). In regard to gastrointestinal disorders, prevalence estimates for people with neurodevelopmental disabilities suggest rates of occurrence of 13% to 50% for gastroesophageal reflux disease (GERD; Böhmer et al., 2002; McElhanon et al., 2014) and 20% to 50% for constipation (Sullivan, 2008; Wang et al., 2011). For immune system disorders, evidence suggests that allergies/sinus infections and asthma occur in people with severe disabilities at 21% to 45% (Aldinger et al., 2015; Haveman et al., 2011) and 16% to 42% (Lyall et al., 2015; Xie et al., 2020), respectively. Central nervous system comorbidities, including epilepsy/seizures, headache/migraine, and sleep dysregulation occur at 14% to 44% (Amiet et al., 2008; Bowley & Kerr, 2000), 11% to 43% (Schieve et al., 2012; Underwood et al., 2019), and 9% to 53% (Richdale & Schreck, 2009; van de Wouw et al., 2012), respectively. Such findings clearly document that people with severe disabilities are at a greater risk for health conditions than many others in our society (King-Dowling et al., 2019; Kohane et al., 2012).

Another pattern that has emerged from the research literature is an association between health conditions and occurrences of challenging behavior (Symons & Kennedy, 2012). The association between specific health conditions and occurrences of challenging behavior is complex, but well documented. For example, an individual who is constipated may be more likely to engage in aggression, self-injury, and/or property destruction (e.g., Carr & Blakeley-Smith, 2006; Christensen et al., 2009). Or, a person whose sleep is disrupted may emit more challenging behaviors on days when they are sleep-deprived (e.g., Kennedy & Meyer, 1996; O’Reilly, 1995). The emergence of functional behavioral assessment (FBA) made possible the careful experimental analysis of the causes of challenging behavior and also facilitated the study of events that can contribute to the occurrence of these behaviors (Iwata et al., 1982; O’Neill et al., 1990). Over the past few decades, the research literate has empirically demonstrated a range of health conditions that have direct or indirect roles in making people aggressive, self-injurious, and/or engage in other behavioral challenges.

Many of the health conditions prevalent among people with severe disabilities are also those associated with challenging behavior. Along with this pattern of health conditions influencing the occurrence of challenging behaviors are two other patterns. First, the large majority of instances in which illness is associated with behavioral challenges are for behaviors that are negatively reinforced (Symons & Kennedy, 2012). Such behaviors function as a means of avoiding or reducing events that are noxious or unpleasant to the individual. For example, a woman who is experiencing symptoms associated with dysmenorrhea (e.g., acute abdominal pain) may act out more aggressively than normal when she is asked to complete certain work tasks (Carr & Owen-DeSchryver, 2007). Or, the presence of allergy symptoms may make a student intolerant of instructional conditions that he may otherwise engage in without behavioral challenges (Kennedy & Meyer, 1996). There are many other examples in which escape or avoidance of specific situations is established by the presence of health conditions.

The second pattern that has emerged from research on health conditions and challenging behavior is the role of pain (Breau et al., 2003; Kennedy & O’Reilly, 2006). In recent years, there has been a growing understanding of how pain is manifested in people with severe disabilities and how the effects of pain alter a person’s quality of life (Genik et al., 2018; Oberlander & Symons, 2006; Richards et al., 2016). In regard to challenging behaviors, most analyses of behavioral function and health conditions suggest that the health event produces pain and/or establishes other stimuli as more noxious, therefore increasing the value of escaping or avoiding certain situations. Thus, the health condition establishes situations as unpleasant or makes unpleasant situations more unpleasant because of the presence of discomfort associated with the health problem. In the majority of cases in which health conditions increase occurrences of challenging behavior, pain seems to be associated with the behavioral challenges either directly or indirectly.

To summarize the accumulated knowledge from the past 30 years of research on health conditions and challenging behavior, I would note the following: (a) We have moved from a limited knowledge that people with severe disabilities have health conditions impacting their quality of life to understanding that this diverse group of people have a wide range of health conditions and those health conditions often occur at a much higher rate than in the general population. (b) The field has evolved from not including health conditions within FBAs to understanding that health conditions can exacerbate challenging behaviors and need to be directly incorporated into FBAs and support plans. (c) We have gained initial insights into the behavioral mechanisms involved in how health conditions impact challenging behavior.

Future Research and Discovery

In the remainder of this article I will discuss future research opportunities associated with health and challenging behavior. While substantive progress has been made, there is still much that is not known and a great deal of research that is necessary (Kennedy & Richman, 2019). Four areas will be discussed: (a) health disparities, (b) interdisciplinary assessment, (c) mechanisms of action, and (d) comprehensive intervention.

Health Disparities

Access to health care and accurate diagnoses of comorbid conditions in people with severe disabilities are central to health management. Unfortunately, people with neurodevelopmental disabilities experience significant disparities in accessing health care, as well as receiving diagnosis and treatment (Krahn et al., 2015). The health disparities for people with severe disabilities are even greater for underrepresented groups (Magaña et al., 2012). In addition, these disparities are not unique to the American health care system and may represent a broader global set of health practices that disadvantage people with the most significant disabilities (e.g., Allerton et al., 2011).

While researchers are beginning to note that people with disabilities, in general, should be considered a group at risk for health disparities (Liptak et al., 2008), more inquiry into subpopulations, such as those with developmental disabilities, is needed. It is likely that access to health care is an interaction among variables such as severity of disability, economic status, cultural differences, and geography. Each of these variables potentially decreases the probability of gaining access to needed health care and interacts with the others to further decrease the likelihood of accessing appropriate care (Allerton et al., 2011; Carrillo et al., 2011). More research specifically focusing on neurodevelopmental disabilities as a domain at risk for health disparities is needed to better understand, and potentially address, inequities in accessing health care.

Interdisciplinary Assessment

For decades, researchers have noted that “diagnostic overshadowing” is a particular concern for people with severe disabilities when receiving health assessments (O’Hara et al., 2010). Diagnostic overshadowing occurs when the complexity of the disability reduces the probability that comorbid health conditions are identified. For example, a child with autism spectrum disorder may engage in head banging and health diagnosticians may focus on the self-injury as the presenting problem to be resolved, but the underlying cause of the behavior may be otitis media—a painful inner ear infection—that can cause head banging (O’Reilly, 1997). However, there are other variables that also contribute to the under diagnosis of health conditions in people with severe disabilities (O’Hara et al., 2010). These include (a) limited verbal communication for describing symptoms, (b) the presence of challenging behavior making diagnostic examinations more difficult, and (c) stressed family support systems. The accurate diagnosis of health conditions in people with severe disabilities, particularly those with challenging behavior, is an understudied area that is critical to understanding and resolving interactions between health and problematic behavior.

The previous observations about access and diagnosis also suggest that an interdisciplinary approach to identifying health concerns among people with severe disabilities is greatly needed. It is even more important when the link between health and challenging behavior is being assessed (Kennedy & Richman, 2019). While strategies do exist for linking health and behavioral assessments (e.g., Chafouleas et al., 2016; Kennedy et al., 2007), the research on process and outcome remains scant. A wide range of expertise is required to effectively assess challenging behaviors and how health conditions may interact with them. Disciplinary expertise includes communication/language, behavior analysis, general/special education, pediatrics/general medical practice, mental health, pharmacy, and other areas of allied health. Questions that need to be addressed include (a) identification at intake of potential disciplinary expertise needed for initial screening, (b) referral practices for follow-up assessment/diagnosis, (c) cross-coordination and translation of assessments and findings, and (d) case coordination among health professionals, educators, other support providers, and family members. Undoubtedly, there are many other areas that need research attention relating to interdisciplinary assessment.

Mechanisms of Action

A third area in need of additional analysis revolves around mechanisms of action. In particular, how behavioral mechanisms interact with the biological mechanisms that are produced by health conditions. As noted previously, the current state of the literature suggests that negatively reinforced challenging behavior is often affected by health conditions and that pain may play a central role in altering the probability of behavior (Symons & Kennedy, 2012). More work relating to the behavioral functions of challenging behavior in relation to health events will be facilitated by behavioral-epidemiological studies looking at larger samples and using consistent, interdisciplinary FBA protocols. It will help interventionists to know what behavioral mechanisms are influenced by various health conditions and this knowledge could assist in the development of interventions.

On a related note, differentiating between mediator and moderator effects for health conditions in relation to challenging behavior awaits development. In the social sciences, mediators refer to variables that directly influence the occurrence of events, whereas moderator effects refer to variables that indirectly influence the cause of events (Baron & Kenny, 1986). For example, otitis media serves as a mediator of self-injurious behaviors such as head banging or head hitting in that the behavior reduces the pain produced by otitis media (O’Reilly, 1995). When otitis media is present, behavioral function is established; when it is not present there is no pain avoidance for the self-injury or head hitting to serve. An example of moderator effects can be illustrated by the role that sleep disruption serves in exacerbating challenging behavior. The function of challenging behavior is typically established by other reinforcers (e.g., task avoidance) and the occurrence of sleep dysregulation alters the motivating operations associated with task avoidance (Kennedy & Meyer, 1996). In this sense, sleep deprivation serves as a moderator variable in that the sleep dysregulation increases the person’s motivation to engage in avoidance behavior. A better understanding of how health and behavior interact may help improve both assessment and intervention by refining the causal nature of the relationship between variables.

Another area that is emerging in the research literature on health conditions and neurodevelopmental disabilities is the search for clusters of health conditions that may be expressed phenotypically with specific types of severe disabilities. For example, obesity, type 1 diabetes, and GERD all co-occur in Prader–Willi syndrome and can contribute to the occurrence of challenging behavior (Butler et al., 2004). As noted previously, researchers are attempting to identify certain clusters of health conditions, such as gastrointestinal, immune, and/or central nervous system disorders, that co-occur more frequently with certain types of severe disabilities (Aldinger et al., 2015; Schieve et al., 2012). A better understanding of comorbidities of health conditions and specific syndromes may assist early diagnosis of health conditions that could exacerbate the development of challenging behavior and, therefore, facilitate both assessment and intervention efficacy and potentially prevent challenging behavior from emerging (Kennedy & Richman, 2019; Richman & Lindauer, 2005).

Comprehensive Intervention

Finally, each of the previous areas has implications for the development of support systems to reduce challenging behavior. A theme throughout this article has been interdisciplinarity. From the initial contact with health and/or educational professionals, a person with severe disabilities and challenging behavior should receive assessments that, as a composite, take a more wholistic view of behavioral issues. As more is learned about how to identify behavioral and biological mechanisms and their interactions, the clearer the need for interdisciplinarity from intake to long-term support will become. Case coordination, multidisciplinary team composition, routinized collaboration, a focus on health and wellness, and improved levels of personal independence all are key elements in such support programs.

Examples of interdisciplinary approaches exist, particularly at the level of school-wide positive behavioral supports for challenging behavior (e.g., Anderson et al., 2013). However, an explicit role for how health care practitioners interface with educational personnel, how care is coordinated across settings by individuals with various levels of training and expertise, and who is responsible for managing these various facets of support need to be more fully explicated. For instance, should a social worker, nurse, special educator, or someone else be responsible for coordinating the various educational, psychological, and health components of assessment and intervention? Currently, the field lacks models of support systems that can manage such a wide variety of interdisciplinary roles, each of which is important for positive health and behavioral outcomes for the person with significant disabilities. Thus, more research on models of support and assessments of their short-term and sustained efficacy is required to build support systems that can address the needs of people with challenging behavior that emphasize the interdisciplinary assessment and treatment of health conditions.

Summary

Over the previous three decades, a substantive amount has been learned about the existence of health conditions among people with severe disabilities. We have learned that certain health conditions are more prevalent in this population than in the general population and that there appear to be health disparities in access to health care and appropriate diagnosis. As research has continued to mature in the assessment of challenging behavior, both in terms of FBAs and broader systems of support, health conditions have emerged as a contributing factor in many instances of problematic behavior. In some cases, the health conditions exacerbate existing functions of challenging behavior (mediators); in other instances, they establish the context for behavioral issues to occur (moderators). Research is only beginning to reveal the mechanisms—behavioral and biological—that cause interactions between behavior and health. Paralleling this observation is the need for further developing models of interdisciplinary assessment and intervention within and across school, home, and community contexts. The topic of health conditions and how they impact challenging behavior in people with severe disabilities, while still early in its development, is a promising area for discovery that provides many translational opportunities for researchers and many potential benefits for people with severe disabilities and their advocates.

Footnotes

Editor in Charge: Robert H. Horner

Declaration of Conflicting Interests

The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Funding

The author(s) received no financial support for the research, authorship, and/or publication of this article.

ORCID iD

Craig H. Kennedy

Author Biography

Craig H. Kennedy is a professor of educational psychology and pediatrics at the University of Connecticut. His research focuses on the interactions between health conditions and challenging behavior in people with neurodevelopmental disabilities.

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