People with intellectual disability (ID) experience high rates of chronic health problems and poor overall health compared to people without disabilities. Recent attention to health risk behaviors such as poor diet, lack of physical activity, and underuse of health care has led to the development of several programs intended to reduce disparities in this population through health promotion programs. A review of the literature was conducted focusing on programs developed to target behavioral changes in the person with ID. Thirteen studies, evaluating 10 different health promotion programs, were found. Programs varied significantly in design, targeted health change, and demonstrated effectiveness. Components of each program are systematically reviewed and recommendations made for future programs based upon the current evidence.
Understanding and improving the health of people with intellectual disability (ID) has seen increasing amount of attention and research in recent years. As researchers and clinicians develop and test health promotion programs for this population, it is essential to evaluate the state of the literature to inform practice. This article first provides an overview of the health of people with ID, discusses some of the contributing factors, and reviews health promotion programs targeting behavioral change in people with ID.
Health of People With ID
Compared to adults without ID, people with ID are more likely to have a variety of health risk behaviors. Adults with ID are more likely to be at an unhealthy weight, and this risk is even greater among women, people with Down syndrome, and those living more independently (Havercamp, Scandlin, & Roth, 2004; Rimmer, & Yamaki, 2006). Weight is also a significant problem for children with ID (Lloyd, Temple & Foley, 2012; Maiano, 2011). As is the case in people without disabilities, being overweight or obese has been linked with issues such as diabetes, hypertension, and high cholesterol (Sohler, Lubetkin, Levy, Soghomonian, & Rimmerman, 2009). Perhaps contributing to the incidence of weight problems in this population is a lack of physical activity. People with ID are likely to be sedentary in their daily lives and less likely to engage in regular physical activity (Prasher & Janicki, 2002; Havercamp et al., 2004). Additionally, people with ID have been found to have less than ideal diets, often lacking the recommended number of fruits, vegetables, dietary fiber, and proteins (Adolfsson, Sydner, Fjellström, Lewin, & Andersson, 2008; McGuire, Daly, & Smyth, 2007). Overall, research suggests that people with ID are likely to have high levels of health risk behaviors that may contribute to the development of chronic health conditions.
Research that has examined chronic health conditions in this population has found equal to or greater incidence of these conditions among people with ID. Using the 2006 Medical Expenditure Panel Survey, researchers using a broad definition of cognitive limitation, found that these people were more likely to have arthritis, asthma, diabetes, high blood pressure, high cholesterol, cardiovascular disease, and have suffered a stroke than people without disabilities (Reichard, Stolzle, & Fox, 2011). Other studies have reported that people with ID have similar risks for chronic health conditions such as cancer, diabetes, cardiovascular disease, and lung disease as people without disabilities (Patja, Eero, & Iivanainen, 2001; Shireman, Reichard, Nazir, Backes, & Greiner, 2010). Higher levels of constipation, epilepsy, hyperlipidemia, and osteoporosis have all been reported among adults with ID (Tyler, Schramm, Karafa, Tang, & Jain, 2010). Additionally, studies have shown that people with ID have poorer dental health with higher levels of untreated dental problems (Haveman et al., 2010).
Given the high rates of health risk behaviors and chronic health conditions experienced by people with ID, assuring health care utilization is a priority. However, while large clinic-based studies have found that people with ID may have adequate rates of general physician visits, fewer primary healthcare visits were reported by people with lower levels of functioning and those living at home (Hall, Wood, Hou, & Zhang, 2007; Lewis, Lewis, Leake, King, & Lindemann, 2002). An Ohio study used electronic health records to compare health service utilization in people with ID compared to people without disabilities over a three-year period, and found that adults with ID were significantly less likely than their counterparts to have had a visit in each of these specialties: gastroenterology, pulmonary, cardiology, OB/GYN, general surgery, and pain management (Tyler et al., 2010). Multiple studies have shown that both women and men with ID are less likely to receive preventative cancer screenings (Havercamp et al., 2004; Lennox, & Kerr, 1997; Swaine, Parish & Luken, 2013). People with ID are generally considered to be one of the most heavily medicated populations, yet they receive subpar psychiatric care. One study found that only 24% of people with ID taking psychotropic medications had a psychiatric consultation in their records, and 36% of people did not have any diagnosis linked to their medication use (Lewis et al., 2002). Most research supports the fact that people with ID experience decreased access to health-care services compared to people without disabilities.
Barriers to Health and Healthy Lifestyles for People With ID
A variety of barriers exist for people with ID when it comes to leading a healthy lifestyle and receiving appropriate health care. In terms of health care access, people with ID may struggle to find a healthcare provider willing to serve them due to social stigma or insurance constraints (Benassi, 2011). In a qualitative study, patients with ID reported experiencing discrimination, difficulty communicating, and lack of knowledge about ID by professionals (Ali et al., 2013). Health care professionals may be unfamiliar or uncomfortable treating patients with ID and though there have been isolated efforts to educate medical students about working with patients who have disabilities, most medical professionals are woefully unprepared to treat patients with ID (Long-Bellil et al., 2011). For people with ID who are able to find a healthcare provider, the provider is less likely to recommend preventative action for people who are overweight/obese (Henderson, et al., 2008). Healthcare professionals without adequate training in ID may also fall prey to diagnostic overshadowing, or attributing problems that the individuals with ID are experiencing to the disability instead of as a co-occurring concern (Reiss, & Szyszko, 1983).
Environmental and attitudinal factors are not the only barriers that people with ID face in obtaining appropriate health care and leading healthy lifestyles. Working knowledge regarding health, health care, and healthy lifestyles allow people to advocate for and work towards their own health goals. Health literacy is “the evolving skills and competencies needed to find, comprehend, evaluate, and use health information and concepts to make educated choices, reduce health risks, and improve quality of life” (Zarcadoolas, Pleasant, & Greer, 2003). In people without disabilities, health literacy is inversely related to health risk behaviors and positively correlated with health care (Gibson, Wardle & Watts, 1998; Lindau et al., 2002; Scott, Gazmararian, Williams & Baker, 2002; Wardle, Parmenter & Waller, 2000).
A few studies have attempted to discern the health knowledge of people with ID. Jobling and Cuskelly (2006) used semi-structured interviews and a series of short tasks to assess the hygiene, substance use, exercise, and healthy eating knowledge of 38 adolescents with Down syndrome. They found that most participants demonstrated basic knowledge of hygiene but had little understanding of substance use, exercise, and healthy eating. A study assessing knowledge of smoking risks in adults with ID found that most were not aware of the risks associated with smoking (Taylor, Standen, Cutajar, Fox, & Wilson, 2004). In a large study of 202 women living in the community, researchers found that knowledge of cervical and breast cancer screenings was limited, especially among women living at home with family (Parish, Swaine, Luken, Rose & Dababnah, 2012). Though the research is sparse, it suggests that people with ID have limited knowledge of health. Research has also indicated that people with ID have particular difficulty effectively advocating for themselves in healthcare settings (Lunsky, Emery & Benson, 2002). This may be related to a lack of general health knowledge, or related to confidence, or perceived ability levels. Given that the lack of health literacy is a predictor of health outcomes in the general population, it is likely that this lack of knowledge negatively affects the health, health risk behaviors, and health care access of people with ID. One area of research that may prove fruitful in working to correct disparities in health for people with ID is health promotion designed to create behavioral changes.
Health Promotion in ID
Though both children and adults with ID are increasingly likely to live in the community with family or other supports instead of large congregate care facilities, they are likely to be missed by widespread health education efforts and unlikely to be included in health promotion programs (Rimmer & Braddock, 2002). Because most adult health behaviors have their root in childhood, school based public education plays an important role in education about health. However, there is virtually no research examining whether or not children with ID benefit from these classes or whether school health curriculums have been modified for children with disabilities (Jobling, 2001). Community health promotion often requires reading skills that may be beyond the skill level of many people with ID. In addition, a growing number of health promotion programs use the Internet as a means of dissemination. People with ID are unlikely to have the capacity to perform Internet searches, pick out relevant information, and synthesize it into their own lives. Social media are a relatively new form of health information dissemination that holds promise; however; people with ID are unlikely to access and benefit from this type of health promotion (Eke, 2011).
Beginning in the 1990s, research dedicated to improving the health of people with ID began to appear in the literature. One line of research that emerged was the development of better screening procedures, designed to identify and treat health risks such as being overweight, having high cholesterol, high fall risk, or needing routine cancer screenings (Cooper et al., 2006; Jones & Kerr, 1997; Robertson, Roberts, Emerson, Turner & Greig, 2011). Programs also emerged that targeted health care professionals with the hope of improving the quality of care that they would provide for their patients with ID (Lennox et al., 2007). A third line of research in health promotion is emerging in the field of ID. These research projects focus on educating the person with ID and using increasing knowledge and skills as a catalyst for change. This type of research is important because it allows people with ID to engage in long-lasting behavioral changes and is in line with the push for self-determinism in this population (Shogren, Wehmeyer, Reese, & O'Hara, 2006).
Few reviews have been conducted on health promotion interventions for people with ID. One review paper addressed physical activity and nutrition interventions (Heller, McCubbin, Drum, & Peterson, 2011). This paper found that there was some evidence of efficacy for nutritional and physical activity based programs and programs that combined the two seemed to have the best outcomes. Jinks, Cotton, and Rylance (2011) reviewed obesity interventions and found that some programs reported successful weight loss and drops in body mass index (BMI). However, due to the weak methodology of many of the studies, they called for more controlled trials and research on long-term outcomes. Though both these reviews were thorough and a helpful addition to the literature, further research is needed to address interventions focused on other areas of health promotion and to include the recent influx of studies looking at health promotion in this field. Though both of these reviews focus on outcome measures as their topic of interest, an alternative approach is to focus upon the type of intervention used to create change. Generally, health promotion programs can be split into two main categories, those that address behavioral changes and those that address environmental changes. Programs that address behavior change generally focus on change at the individual level, while those that address the environment have a wide range of foci including society, government, and organizations. They seek to create change in a wider sphere that will affect individuals indirectly (Bartholomew, Parcel, Kok, Gottlieb, & Fernandez, 2011).
This review article focuses on health interventions that target behavior change in the person with ID as the mechanism for action. The results of this review are intended to extend the literature in three ways. First, it is important to discern if behaviorally based health interventions for people with ID are a viable option for improving the health of this population. Second, we wish to provide guidance as to what programs have the most empirical support. As the number of programs designed to address the health and wellness of people with ID continues to grow it is important to critically evaluate the strength of these programs. Without methodologically sound research evaluating these programs, it is impossible to make educated decisions regarding the efficacy of programs. Without demonstrated efficacy, it will be difficult to obtain funds and for organizations to adopt and implement program materials. To move the field forward in an effective way, there must be clarification on which approaches are most feasible for this population. For this reason the literature was reviewed and programs systematically evaluated for both strength of study design and efficacy. Last, as health promotion interventions are a relatively new area of research in people with ID, this review will draw on established guidelines and recommendation that have been developed from years of research into efficacy of health promotion program targeting people without disabilities. Understanding of what has been shown to work for people without disabilities and how it may be applied to people with ID will help researchers and program implementers choose programs and improve existing programs for this population.
Literature was identified using the WorldCat search engine through a large public university, Google Scholar, and citation tracking. Literature from the year 2000 on was searched. Citation tracking consisted of following “cited by” links on Google Scholar and checking the references of any review papers found on the topic. Initial searches were conducted in July of 2013 and an updated search was performed in October of 2013. The following Boolean search terms were used: intellectual disability OR mental retardation OR learning disabilities OR developmental disabilities AND health AND promotion OR intervention OR program.
Studies were included if they were published in English, appeared in a peer-reviewed academic journal, and reviewed a behavior related intervention that targeted the individual with ID. Interventions targeting both children and adults were included. Studies were excluded if they did not involve the person with ID or if the end goal was not to induce a behavior-related change to address some form of health or health behavior. For example, several studies evaluated weight changes based on attendance of exercise classes for people with ID. These studies were excluded if they did not seek to change behavior beyond the length of the study. A study which was twofold, containing both education regarding nutrition and how to plan and complete exercise that also included an exercise program would be reviewed. Additional exclusion criteria included single-case studies, and interventions without measurable outcome criteria such as purely qualitative studies. Over 1,600 abstracts were reviewed with the majority being excluded due to not being an intervention, targeting a population other than people with ID, or not targeting behavioral change.
A helpful method for reviewing groups of health promotion programs is a meta-analysis, a statistical analysis to show the effect of each type of health promotion program, usually only including randomized control trials (RCTs), and provide recommendations regarding the efficacy of various interventions. The body of literature on health promotion in ID is not yet developed enough to conduct this type of analysis, as only six RCTs were found and little continuity existed between studies. For this reason, the review will include nonrandomized studies (NRS) and the focus will be on evaluating level of evidence for each program, as well as making recommendations for future researchers.
The Cochrane Collaboration is an international organization that aims to provide systematic reviews related to health care in order to facilitate informed decision making by consumers. They publish and update the Cochrane Handbook for Systematic Reviews, a text design to provide guidelines for authors in conducting systematic reviews of health interventions. The Cochrane Handbook provides specialized instructions for the reviews of health promotion interventions, noting that health promotion reviews generally include a large variety of study designs and approaches and that gathering information on the contexts and intervention characteristics will provide information on outcomes.
The Cochrane Collaboration acknowledges that assessing health promotion research differs from other types of interventions and may include many NRS. They recommend using caution when assessing results of NRS and call for reviewers to use their judgment in assessing the quality of these studies (Armstrong, Waters, & Doyle, 2008). One tool that is recommended for use in assessing the strength of the study design is the Quality Assessment Tool for Quantitative Studies (Effective Public Health Practice Project, 2007). This standardized tool evaluates components of the intervention such as design, selection bias, confounding, blinding, data collection, and withdrawals and drop-outs and gives an overall rating of strong, moderate or weak. See Table 1 for systematic rating using this approach. It should be noted that a few interventions had been examined in multiple studies; in these cases the study with the strongest methodology was reviewed.
Thirteen studies evaluating 10 different programs were identified. Ten of these studies focused on general health and addressed topics such as weight management, nutrition, and physical activity. Most of these studies were for adults with ID, though one study did address children with ID. Three studies were found that focused on improving health communication, all targeting adults. Two studies, the Health Matters Study and the Bergstrom Study, were graded as having strong study designs. Two studies, the Women Be Healthy and the Ask Diary, were graded as having moderate study designs, while the other six studies were graded as having weak study designs. See Table 2 for a brief overview of each study by intervention target.
The majority of the interventions found were graded as weak using the Quality Assessment Tool for Quantitative Studies. This is not to say that the interventions themselves were of low quality, but rather the design that was used to quantitatively test the studies was not judged to be of strong quality. Some of these studies reported no significant effect of the intervention on outcome measures while others reported robust effects. However, given the design quality of these studies it is difficult to judge the true effect of these interventions. Additional research is needed to clarify the efficacy of these studies. The Ask diary and Women Be Healthy curriculum both had moderately strong designs. No evidence was found for the use of the Ask diary, though the authors suggested that a different study design and study length may be needed to pick up any effect of the intervention. Some support was found for the Women Be Healthy program but significant issues such as contamination of the sample and limitations of outcome measures made it difficult to assess the true effect of the program. The Health Matters curriculum and the Bergstrom study were the only two interventions rated as having a strong design. The Health Matters program reported significant changes after the completion of the program in several key areas, such as nutritional habits, knowledge, and exercise frequency. The Bergstrom study had a significant increase in steps per day as measured by pedometers but other outcome measures were nonsignificant.
Overall, there is preliminary evidence that behaviorally based health promotion interventions are effective for people with ID. The results of this review showed that recruiting for and conducting behaviorally based health interventions in this population are feasible and that a wide variety of service agencies and health care providers are willing to participate. In terms of effective interventions it is the opinion of this reviewer that, given the strength of study design and positive outcomes, the Health Matters curriculum had the most empirical support. That being said, the field of health promotion for people with ID is relatively new and does not contain enough evidence to suggest any type of “gold standard” intervention and all of the studies reviewed in this paper would benefit from additional research.
Conclusions and Limitations
Thirteen studies examining the efficacy of health promotion programs that targeted behavioral change were reviewed. Several of the programs were adaptations of programs that were initially developed for people without disabilities but most of the programs were developed specifically for adults with ID. All of the studies were published later than 2000, and most of the studies were published in the past 5 years. Health promotion in this population is a fairly new research topic but seems to be growing and evolving. The health promotion interventions were evaluated using the Quality Assessment Tool for Quantitative Studies. Only two studies were judged to have strong methodology using this instrument.
It should be noted that this review was limited by several factors. Though every effort was made to use all relevant search terms and include all relevant literature it is possible that some studies were overlooked. Additionally, only published articles were included; and no attempt was made to contact researchers for unpublished works. A single researcher conducted the review and thus there is no reliability information for inclusion/exclusion criteria.
Though research has demonstrated that children with ID are likely to have inadequate health care and poorer health when compared to their nondisabled peers there is very little research in this population. This is juxtaposed to the extensive literature available regarding health promotion interventions for children without disabilities. Though many health promotion materials have been designed for use in schools, no research was found that addressed the inclusion of children with ID in these interventions. It is likely that children with ID are often excluded from this type of research. If they are to be included in these programs, there must be some evaluation of appropriateness and efficacy. As Mann, Zhou, McDermott, and Poston (2006) found in the initial Steps To Your Health study, adults with ID do not seem to reap the same benefits as adults without disabilities when they are simply included in health promotion program designed for people without ID. The same may hold true for children, and this should be determined when trying to assess the best way to reduce the health disparities in children with ID.
The majority of these studies were conducted on people with ID at less severe levels. Research has demonstrated health disparities across level of disability and it will be important for researchers to examine the use of these programs in people with more severe disabilities. Because many of these interventions incorporate learning written or spoken material, different activities or the greater inclusion of caregivers into the program may be needed. Research will need to examine how health promotion programs may be adapted to be meaningful for people with more severe disabilities and how best to balance the tension between the right to choice and healthy lifestyles.
Last, there are still areas for health promotion that have been left unexplored. There are many health promotion programs that have been designed to address management of specific chronic health conditions, but these have not been adapted for people with ID (Munro, Lewin, Swart, & Volmink, 2007; Norris, Engelgau & Narayan, 2001). Given that people with ID have similar or higher levels of chronic health conditions as the general population health promotion programs designed to improve care of specific conditions may be warranted. People with ID are considered to be one of the most heavily medicated populations (Reiss & Aman, 1997). Despite this, relatively few attempts have been made to educate people with ID regarding medication regiments or how to be active in the discussion of their own medication use. Aman, Benson, Farmer, Hall and Malone (2007) developed booklets for people with ID called Project MED (Medication Education for Consumers) intended to give information regarding medication uses, side effects, and patients' rights. Though no formal assessment of knowledge gains was made, through a survey patients reported satisfaction with the materials. Future health promotion programs should strongly consider targeting issues surrounding medication use in people with ID.