Mitigating the Impact of Low Health Literacy on Older Adults' Self-care
There is burgeoning interest in understanding the impact of health literacy on health care in the United States. Nearly 44 million adults are estimated to have inadequate health literacy, putting them at risk for unsuccessful self-care and poor health outcomes (DeWalt, Berkman, Sheridan, Lohr, & Pignone, 2004; Nielson-Bohlman, Panzer, & Kindig, 2004). Older adults are especially likely to have inadequate health literacy, compromising their health outcomes (Paasche-Orlow, Parker, Gazmararian, Nielson-Bohlman, & Rudd, 2005). Recent reviews emphasize the need to better understand health literacy in order to explain why older adults with inadequate health literacy have trouble accomplishing self-care and experience worse outcomes. Such knowledge would provide the foundation for developing strategies to mitigate effects of low health literacy on health outcomes (Nielson-Bohlman et al., 2004). Psychologists can help tackle this complex health care problem as members of multi-disciplinary research teams by providing expertise in behavioral science theory and methodology.
A framework for health literacy
Language comprehension is central to health literacy, which is commonly measured by tests requiring reading of health-related material (e.g., STOFHLA, Baker, Williams, Parker, Gazmararian. & Nurss, 1999; other abilities such as numeracy and comprehension of graphics are also important). Nonetheless, theories of comprehension have not been integrated with the concept of health literacy. We are developing a framework that helps integrate health literacy and health care systems with models of comprehension and cognitive aging (Morrow, Clark, Tu, Wu, Weiner et al., 2006). According to models of comprehension, people understand text such as medication instructions at multiple levels: At the surface level, they represent word-level meaning and syntactic form; at the textbase level, interconnections among word meanings are represented as ideas, which are integrated to represent the content explicitly conveyed by the text; at the situation model level, text content is integrated with knowledge to represent the situations described by the text (Kintsch, 1998). The situation model is critical for translating language to action, such as learning how to take medication from instructions. The processes that produce these representations depend on general cognitive abilities such as working memory. Older adults are generally less successful than younger adults at creating textbase representations because of age-related declines in working memory and other cognitive abilities, but they are often adept at creating situation models in part because they know as much or more than younger adults about domains relevant to understanding the text (Wingfield & Stine-Morrow, 2000). However, this age-related strength highlights a dilemma for older adults with low health literacy: They are less able to offset typical age-related cognitive declines with knowledge relevant to comprehension because they tend to have limited knowledge about health topics (e.g., DeWalt et al., 2004).
Partial support for our framework comes from a recent study that helps link health literacy to general cognitive abilities (Morrow, Clark et al., 2006). In a sample of older adults diagnosed with heart failure, we found that participants who were older scored lower on the STOFHLA measure of health literacy (a common finding, e.g., Gazmararian, Baker, Williams, Parker, Scott et al., 1999). More interesting, age-related differences in health literacy were explained by differences in general cognitive abilities such as speed of processing as well as by education, as predicted by theories of aging and comprehension (Wingfield & Stine-Morrow, 2000). Such findings also suggest the need to design health communication that reduces demands on older adults' cognitive and literacy abilities. This need for better communication is also clear from the health literacy literature: Lower literacy patients are less likely to understand written (for review see Andrus & Roth, 2002) and spoken (e.g., Schillinger et al., 2003) information needed for self-care. In terms of our framework, it appears that older adults with low health literacy have trouble creating accurate situation models from health care documents such as medication instructions, because these documents often contain complex language and dense content and older adults lack the relevant background knowledge to interpret them.
Improving health outcomes for older adults with health literacy
I've had the opportunity to collaborate with an inter-disciplinary team that includes pharmacists, gerontologists, and behavioral scientists on a project funded by the National Institute on Aging. Our goal is to improve medication use and health outcomes in a sample of older adults with diverse literacy and cognitive abilities, and diagnosed with heart failure (Murray, Young, Morrow, Weiner, Tu et al., 2004). We developed a patient-centered educational intervention that was compared to a usual care control group, with heart failure medication adherence electronically monitored over a 12-month period. Participants' medications were placed in pill bottles with lids containing computer chips that recorded when participants opened the containers. The intervention was pharmacy-based, reflecting the increasingly important role that pharmacists play in medication management for older adults (Hammond, Schwartz, Campbell, Remington, Chuck, et al., 2003). It involves written and spoken communication that addresses literacy and cognitive barriers to understanding how and why to take medication (Morrow, Weiner, Deer, et al., 2004). The written instructions are designed to be consistent with how older adults think about taking medication. They use simple language (reflected in high readability scores) to present only the information needed to safely take the medication. This information is organized according to a general procedural schema shared by older and younger adults, so that information order in the instructions matches patients' expectations. The instructions also contain pictorials that explicitly convey information about when and how much medication to take. Such instructions should support the ability to create a situation model for taking medication, despite age-related cognitive declines. We have found that older adults (varying in health literacy) better understood and remembered these instructions than typical instructions for the same medications available in a large chain pharmacy, primarily because they better recalled the information conveyed by pictures as well as text (Morrow, Weiner, Young, Steinley, Deer et al., 2005). Patients with lower health literacy were especially likely to prefer the patient-centered instructions (Morrow, Weiner, Steinley et al., 2006). Consistent with our framework, health literacy differences in both comprehension and preferences were partly explained by differences in cognitive ability (e.g., processing speed). The spoken communication part of the intervention involved the pharmacist discussing with patients how to take their medications, following the same medication taking schema as in the written instructions, as well as helping to identify barriers to taking the medications.
The most important question is whether this patient-centered health communication helps patients with lower health literacy to successfully take their heart failure medications. Preliminary analysis of the medication adherence findings in our study suggests that participants with lower health literacy had lower adherence (Murray, Young, Hoke, Tu, Weiner, et al., 2006), which converges with other studies showing that lower literacy patients are less successful in accomplishing self-care tasks (e.g., DeWalt et al., 2004). Most important, our patient-centered intervention improved medication adherence, and mitigated differences in adherence associated with health literacy: Literacy differences were significant in the control, but not the intervention group.
Health literacy is a multi-faceted concept that explains differences in patients' self-care and health outcomes, especially among older adults with chronic illness. My colleagues and I are developing a framework that links health literacy to age-related differences in cognitive abilities relevant to comprehension and self-care. Guided by this framework, we developed a patient-centered approach to improving health communication for older adults with inadequate health literacy, so that they better understand how to perform self-care tasks despite age-related declines in general cognitive abilities. We find that older adults with lower health literacy better understand and prefer medication instructions designed to reduce comprehension demands. The patient-centered intervention also improves medication adherence among older adults with CHF, with some evidence that it reduces disparities in adherence associated with health literacy differences.
This finding suggests that comprehension of self-care information mediates health literacy and self-care behaviors, although this link still needs to be directly tested. An important part of establishing this link will be to more precisely specify which comprehension processes and representations are impaired among patients with low literacy, and why (e.g., the role of cognitive ability and health knowledge). However, it is likely that improving patients' understanding of self-care tasks will not guarantee successful self-care. Patients may clearly understand how to take their medication, but forget to do so at the appropriate time. Cognitive abilities such as working memory and executive function are likely to play an important role in this prospective memory component of self-care (Insel, Morrow, Brewer, & Figueredo, 2006). Moreover, health literacy involves more than cognition, such as cultural and community resources. Interventions to improve self-care should build on these resources as well (Nielsen-Bohlman, et al., 2004).
Finally, our project highlights the important role that psychologists can play in tackling complex health care problems as members of multi-disciplinary teams.
Andrus, M. R., & Roth, M. T. (2002). Health literacy: A review. Pharmacotherapy, 22, 282-302.
Baker, D. W., Williams, M. V., Parker, R. M., Gazmararian, J. A., & Nurss, J. (1999). Development of a brief test to measure functional health literacy. Patient Education and Counseling, 38, 33-42
DeWalt, D. A., Berkman, N. D., Sheridan, S., Lohr, K. N., & Pignone, M. P. (2004). Literacy and health outcomes: A systematic review of the literature. Journal of General Internal Medicine, 19, 1228-1239.
Gazmararian, J. A., Baker, D. W., Williams, M. V., Parker, R. M., Scott, T. L., Green, D. C., Fehrenbach, S. N., Ren, J., & Koplan, J. P. (1999). Health literacy among medicare enrollees in a managed care organization. JAMA, 281, 545-551.
Hammond RW, Schwartz AH, Campbell MJ, Remington TL, Chuck S, et al. (2003). Collaborative drug therapy management by pharmacists. Pharmacotherapy, 23, 1210-25.
Insel, K.C., Morrow, D.G., Brewer, B.B., & Figueredo, A.J. (2006). Cognitive function and medication adherence. Journal of Gerontology: Psychological Sciences 60B, P102-P107.
Kintsch, W. (1998). Comprehension: A paradigm for cognition. New York, NY: Cambridge University Press.
Morrow, D.G., Clark, D., Tu, W., Wu, J., Young, J., Weiner, M., Steinley, D., & Murray, M. (2006). Correlates of health literacy in older adults with chronic heart failure. The Gerontologist. In press.
Morrow, D.G., Weiner, M., Deer, M., McGuire, P., Young, J., Dunn, S., & Murray, M. (2004). Patient-centered instructions for medications prescribed for the treatment of heart failure. The American Journal of Geriatric Pharmacotherapy. 2, 44-52.
Morrow, D.G., Weiner, M., Steinley, D., Young, J., & Murray, M. (2006). Patients' experience with instructions and health literacy influence preferences for written heart failure medication instructions. Journal of Aging and Health. In press.
Morrow, D. G., Weiner, M., Young, J., Steinley, D., Deer, M., & Murray, M. (2005). Improving medication knowledge among older adults with heart failure: A patient-centered approach to instruction design. The Gerontologist, 45, 545-552.
Murray, M.D, Young, J., Hoke, S., Tu, W., Weiner, M., Wu, J., Smith, F., & Morrow, D.G. (2006, Nov). Effects of a multilevel pharmacy-based intervention on medication adherence and health outcomes in low-income patients with heart failure: Results of a randomized, controlled trial. American College of Physicians Foundation 2006 Health Communication Conference, Washington D.C.
Murray, M. D., Young, J., Morrow, D. G., Weiner, M., Tu, W., Hoke, S., Clark, D., Stroupe, K., Wu, J., Deer, M., Bruner-England, T., Sowinski, K., Smith, F. A., Oldridge, N., Gradus-Pizlo, I., Murray, L., Brater, C., & Weinberger, M. (2004). Methodology of an ongoing, randomized, controlled trial to improve drug use for elderly patients with chronic heart failure. The American Journal of Geriatric Pharmacotherapy, 2, 53-65.
Nielsen-Bohlman, L., Panzer, A. M., & Kindig, D. A. (2004). Health literacy: A prescription to end confusion. Washington, DC: The National Academies Press.
Paasche-Orlow, M.K., Parker, R.M., Gazmararian, J.A., Nielsen-Bohlman, L.T., & Rudd, R.R. (2005). The prevalence of limited health literacy. Journal of General Internal Medicine, 20, 175-184.
Schillinger, D., Grumbach, K., Piette, J., Wang, F., Osmond, D., Daher, C., Palacios, J., Sullivan, G. D., & Bindman, A. B. (2002). Association of health literacy with diabetes outcomes. JAMA, 288, 475-482.
Wingfield, A., & Stine-Morrow, E. A. L. (2000). Language and speech. In F. I. M. Craik & T. A. Salthouse (Eds.), The handbook of aging and cognition (pp. 359-416). Mahwah, NJ: Erlbaum
About the Author
Dan Morrow is associate professor at the University of Illinois at Urbana-Champaign with appointments in the Human Factors Division (Institute of Aviation) and the Beckman Institute for Advanced Science and Technology. He received a PhD in cognitive psychology from the University of California Berkeley, followed by a postdoctoral fellowship at Stanford University. His research interests include the impact of age-related differences in cognitive function on complex task performance, designing environments to support older adults in aviation and health care domains. He has been funded by NIH to investigate relationships between expertise and aging in pilot performance, and to develop communication strategies to improve older adults' self-care (medication adherence and appointment attendance). He is a member of APA Divisions 20 and 21, and serves on the editorial board of Psychology and Aging.