Journal of Psychosocial Nursing and Mental Health Services

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CNE Article 

Interventions to Reduce Cognitive Decline in Aging

Kristine N. Williams, RN, PhD; Susan Kemper, PhD

Abstract

As the population ages, risks for cognitive decline threaten independence and quality of life for older adults and present challenges to the health care system. Nurses are in a unique position to advise older adults about cognitive health promotion and to develop interventions that optimize cognition in older adults. A literature review was conducted to provide nurses in mental health and geriatric care with an overview of research related to the promotion of successful cognitive aging for older adults. Research evaluating cognitively stimulating lifestyles and the effects on cognitive function in older adults of interventions targeting cognitive training, physical activity, social engagement, and nutrition were reviewed. Overall research findings support positive effects of cognitive and physical activity, social engagement, and therapeutic nutrition in optimizing cognitive aging. However, the strength of the evidence is limited by research designs. Applications for health promotion to optimize cognitive aging and future directions for research are discussed.

Abstract

As the population ages, risks for cognitive decline threaten independence and quality of life for older adults and present challenges to the health care system. Nurses are in a unique position to advise older adults about cognitive health promotion and to develop interventions that optimize cognition in older adults. A literature review was conducted to provide nurses in mental health and geriatric care with an overview of research related to the promotion of successful cognitive aging for older adults. Research evaluating cognitively stimulating lifestyles and the effects on cognitive function in older adults of interventions targeting cognitive training, physical activity, social engagement, and nutrition were reviewed. Overall research findings support positive effects of cognitive and physical activity, social engagement, and therapeutic nutrition in optimizing cognitive aging. However, the strength of the evidence is limited by research designs. Applications for health promotion to optimize cognitive aging and future directions for research are discussed.

Dr. Williams is Associate Professor, Kansas University Medical Center School of Nursing, Kansas City, and Dr. Kemper is Roberts Distinguished Professor, Gerontology Center, University of Kansas, Lawrence, Kansas.

The authors disclose that they have no significant financial interests in any product or class of products discussed directly or indirectly in this activity. The authors are supported by the Building Interdisciplinary Research Careers in Women’s Health (BIRCWH) K-12 Program (K12 HD052027, P. Thomas, PI) at the Kansas University Medical Center School of Medicine.

Address correspondence to Kristine N. Williams, RN, PhD, Associate Professor, Kansas University Medical Center School of Nursing, 3901 Rainbow Boulevard, MS 4043, Kansas City, KS 66160-7502; e-mail: kwilliams1@kumc.edu.

Received: March 31, 2009
Accepted: January 26, 2010
Posted Online: May 10, 2010

As the population ages, risks for cognitive decline threaten independence and quality of life for older adults and present challenges to the health care system. Brain health programs developed by aging interest groups such as the AARP and the Alzheimer’s Association provide directives for nutrition, physical and cognitive activities, and other lifestyle modifications to enhance older adults’ cognition and memory. Computer training, memory tapes, and video games are also marketed to the lay public with claims of enhancing cognition, assuming that “use it or lose it” applies to cognitive as well as physical health (Casel, 2002). As health care experts, nurses may be asked to advise older adults about ways to optimize cognitive abilities in aging.

Geriatric and mental health nurses are in a unique position to identify changes in older adults’ cognition, distinguishing between normal and pathological processes, and also providing cognitive health promotion. Thus, nurses need to be knowledgeable about cognitive aging as a basis for educating clients and for developing and testing interventions to promote cognitive well-being. This article provides an overview of the current state of the science in cognitive aging and a review of recent research with implications for practice and future research.

The review identified research reports completed since 2000 by searching the terms cognition and aging in MEDLINE, Cumulative Index to Nursing and Allied Health Literature (CINAHL®), and PsycINFO® databases. Additional significant research prior to 2000 was identified from manuscript references. More specific search terms including lifestyle factors, cognitive and exercise interventions, and social engagement were included to narrow topics and organize the review.

Cognitive Changes in Aging

Knowledge of the normal and pathological changes in cognition that occur with aging is essential to understanding interventions to optimize cognition in older adults. Normal cognitive aging includes established declines in cognitive processes that affect older adults’ functional abilities related to everyday tasks such as driving, banking, and medication administration (Fillit et al., 2002). Cognition or intelligence includes abilities such as using symbols and abstractions, acquiring new information, and adapting to changing situations. The intelligence quotient was developed to provide an index of cognition, including assessment of mathematical reasoning, word fluency, vocabulary, inductive reasoning, and spatial orientation. Intelligence, learning, and memory are three key cognitive domains that normally change during aging and have implications for maintaining independence and quality of life (Hooyman & Kiyak, 2007).

The Seattle Longitudinal Study was a randomized controlled clinical trial that compared cognitive assessments initially collected in 1956 and continued throughout seven intervals in members of a health maintenance organization. Contextual, health, and personality variables were measured in relation to cognitive abilities and real-life tasks (Schaie, Willis, & Caskie, 2004).

The study established that age-related patterns of decline in specific intellectual abilities vary among aging individuals but that fluid (or process-based) intelligence declines earlier than crystallized abilities (i.e., those based on accumulated knowledge). Fluid ability declines occur at younger ages in women, increasing disability for this population that outlives male counterparts. Even crystallized abilities decline by the late 70s, and reductions in perceptual speed start in young adulthood. Most individuals experience measurable cognitive loss by age 60, with widespread declines by age 75 (Schaie et al., 2004). During the past decade, research has focused on determining why some older adults have preserved cognitive function in aging as a basis to develop and test interventions to maintain cognitive abilities of older adults.

Theories of Cognitive Aging

Theoretically, age-related cognitive changes normally occur as outcomes of distal or proximal life events. Distal events are early life experiences such as physical, cultural, and social conditions that influence cognitive development and functioning. For example, vocabulary becomes increasingly diverse with age. In contrast, current cohorts of older adults who were not exposed to computers as children are challenged by this new technology. Continued use of established cognitive abilities is also important to maintain performance (Fillit et al., 2002).

Proximal (recent) factors also contribute to reduced cognitive performance in aging. Multiple serial cognitive processes including processing speed, size of working memory, inhibition of extraneous environmental stimuli, and sensory losses contribute to cognitive decline. Cognitive capacity remains intact with aging, but encoding, storage, and retrieval become less efficient or are interrupted by reduced attention and working memory capacity (Fillit et al., 2002). Slowed processing speed can interfere with problem solving by extending the time required for older adults to perceive, interpret, select, and execute responses.

Reduced working memory occurs due to slowed processing involving the sequence of recall (Kramer, Bherer, Colcombe, Dong, & Greenough, 2004). Limited amounts of information are held in working (short-term) memory for immediate recall or are encoded and stored in secondary (long-term) memory. In aging, actual memories are preserved. However, short-term memory (the amount of information held in immediate consciousness) is reduced, and retrieval of information from long-term memory stores is slowed. Reductions in the efficiency of encoding and recall, attention, and brain plasticity (the ability to adapt to novel information) are also implicated as normal changes in cognitive aging (Hooyman & Kiyak, 2007).

National Institutes of Health experts from the Aging, Mental Health, and Neurological Diseases and Stroke Institutes have identified a need for research on healthy brain aging to include demographic, social, and biological determinants of cognitive and emotional health in older adults (Hendrie et al., 2006). An expert panel identified socioeconomic, education, physical, and psychosocial factors as determinants of cognition in aging. The panel called for research in four key areas with promise for improving cognitive aging:

  • Cognitive activity.
  • Physical activity.
  • Social engagement.
  • Nutrition.

This review presents research findings of studies that examined relationships between lifestyle and activities factors and cognition in aging, followed by research testing targeted interventions to improve cognition focusing on cognitive activity, physical activity, social engagement, and nutrition.

Lifestyle Factors Associated with Maintained Cognition

Research has identified lifestyle practices such as education, leisure pursuits, intellectual engagement, and expertise that are associated with successful maintenance of cognitive abilities. Physical activity, diet, and social activity are additional factors linked to maintained cognition in aging that have been used as a basis for interventions to prevent cognitive decline.

Cognitive Activity Factors

The MacArthur Studies of Successful Aging established the psychological and physiological benefits of education on cognition in aging individuals (Kubzansky, Berkman, Glass, & Seeman, 1998). It has been established that education exerts protective effects on both memory and crystallized intelligence (accumulated knowledge), with minor effects on fluid cognition (processing speed and abilities). Cognitive inactivity has been associated with reduced performance on fluid intelligence measures, whereas use of cognitive abilities can minimize effects of low educational level. Other research supports the effects of socioeconomic status and prior life experiences on cognitive performance in older adults (Kramer et al., 2004).

Individuals with cognitively stimulating occupations maintain higher cognitive functioning as they age. College professors, pilots, physicians, musicians, and architects have been studied as high cognitive activity groups. Occupational complexity or mental activities that demand thought processing and independent judgment have been correlated with higher performance on measures of intellectual flexibility, memory, verbal abilities, fluency, and visual-spatial measures in aging. Older adults in cognitively demanding occupations function higher than same-age peers; however, their performance eventually declines with advancing age (Salthouse, 2006).

Chess and bridge are leisure activities that demand working memory and reasoning skills. Older adults who play bridge score higher on working memory and reasoning measures compared with nonplayers, and working crossword puzzles has also been associated with maintained cognition in older adults (Mireles & Charness, 2002). However, other research on self-selected leisure activities fails to support these findings. Individuals who reported a high frequency of participation in cognitively demanding activities did not have higher cognitive performance in a subsequent study (Salthouse, Berish, & Miles, 2002). Although the majority of correlational studies suggest benefits from cognitively demanding activities, more rigorous research designs will be needed to establish firm causal relationships.

Physical Activity Factors

Many studies have investigated physiological benefits of physical exercise in aging; however, few studies have examined potential cognitive benefits. Physical activity should enhance cognition as cardiovascular fitness increases cerebral blood flow and oxygen delivery to the brain, thereby increasing neuron formation and maintaining brain volume (Etnier, Nowell, Landers, & Sibley, 2006).

Yaffe, Barnes, Nevitt, Lui, and Covinsky (2001) investigated women older than 65 who were physically and cognitively healthy. Participants reported the number of blocks they walked at baseline (also used to estimate caloric expenditure). Those who walked more (adjusted for health, medication, and lifestyle factors) were significantly less likely to demonstrate cognitive declines in the Mini-Mental State Examination (MMSE) (Folstein, Folstein, & McHugh, 1975) 6 years later.

The Nurses’ Health Study (N = 1,800) provides additional evidence that physical activity reduces risk for cognitive decline. Computed energy expenditures for reported activities of participants between ages 70 and 81 were regressed on cognitive measures over time. Those reporting highest levels of activity had a 20% risk reduction for cognitive decline and dementia (Weuve et al., 2004).

Another study by van Gelder et al. (2004) provides evidence of benefits of physical activity in later life. Participants who maintained or increased their physical activity were nearly four times less likely to exhibit cognitive decline, as measured by MMSE scores. Men in the lowest activity quartile at baseline had significantly elevated risks for cognitive decline as they aged.

A study of 1,000 older adults in rural communities relied on multiple regression to predict relationships between self-reported exercise and MMSE score changes in a 2-year period (Lytle, Vander Bilt, Pandav, Dodge, & Ganguli, 2004). The highest exercise group had an odds ratio of 0.39 (95% confidence interval [CI] = 0.19 to 0.78) for significant declines in MMSE scores. Even the least frequent and strenuous level of exercise exhibited some protective effects on cognition in this study (Lytle et al., 2004).

Social Engagement Factors

Other researchers have examined how social support and engagement in social activities affect cognition in aging and determined that social involvement and productive activities lower mortality outcomes as much as physical exercise. As part of the Epidemiological Study of the Elderly, more than 2,000 community-dwelling older adults reported their social, fitness, and productive activities (Bassuk, Glass, & Berkman, 1999). Older adults with higher social activity had lower mortality after 13 years, controlling for age, sex, race and ethnicity, marital status, income, body mass index, smoking, functional disability, and comorbidities. Participants with fewer social ties were at increased risk for cognitive decline, after controlling for multiple factors. The 12-year odds ratio for avoiding cognitive decline was 2.37 (95% CI = 1.07 to 4.88) for socially involved older adults (Bassuk et al., 1999).

Another study found actual involvement with one’s social network, rather than just having an available network, protected against cognitive decline (Seeman, Lusignolo, Albert, & Berkman, 2001). Productivity, defined as participation in 18 activities within domains of housework, yardwork, child care, and paid and volunteer work, was also associated with improved cognitive performance. A study of 350 older adults used multivariate analysis to examine relationships between social network characteristics (network size, contact frequency, and emotional support received) in relation to changes in global cognition (MMSE) that occurred during a 12-year period (Holtzman et al., 2004). Actual engagement and receipt of emotional support, not just the availability of a social network, provided protective effects on cognition (Holtzman et al., 2004).

Trajectories of cognition and social relations were examined during a 7-year period in another study. Beland, Zunzunegui, Alvarado, Otero, and del Ser (2006) found social integration, family ties, and engagement with family were all associated with maintained cognitive function in older adults. Specifically, social integration, reflected by participation in community activities, was protective of cognitive abilities in cohorts with the most advanced age.

Nutritional Factors

Nutrition has been identified as a critical factor in successful cognitive aging as well as in abnormal cognitive decline including dementia. The limited research in this area uses cohort studies to identify nutritional intake and metabolic indicators correlated with cognitive performance in aging. Supplements such as antioxidants, vitamins, fats, and minerals, prescribed for common chronic diseases such as hypertension, hyperlipidemia, and diabetes, also show beneficial effects on cognitive aging. Elevated inflammation and vascular disease markers, such as homocysteine, are implicated in abnormal cognitive decline and dementia. Vitamins B6 B12, and folate and may reduce homocysteine. Diets featuring polyunsaturated fats and omega-3 fatty acids are also associated with maintained cognition in older adults, whereas trans fats and saturated fats are associated with cognitive decline. Antioxidants, such as vitamins C and E, that show promise in limiting vascular inflammation, are now being evaluated as supplements to reduce cognitive decline in aging adults (Morris, 2006).

Diet in relation to MMSE scores was studied in malnourished African older adults (Ojofeitimi et al., 2002). Participants who took vitamin supplements demonstrated improved scores, suggesting a protective effect of vitamins on cognition in nutrient-deficient older adults (Ojofeitimi et al., 2002). In another study, nutrient intake was correlated with cognitive scores of rural-dwelling Italian older adults, after controlling for age, gender, education, total energy intake, cigarette smoking, alcohol consumption, and physical activity (Correa Leite, Nicolosi, Cristina, Hauser, & Nappi, 2001). A healthy diet was negatively correlated with cognitive decline (cumulative odds ratio = 0.85; 95% CI = 0.77 to 0.93).

The ongoing Nutrition, Aging, and Memory in Elders Study will evaluate potential relationships between multiple cognitive measures and blood levels of hematological factors, electrolytes, micronutrients, macronutrients, minerals, proteins, amino acids, lipids, and genetic markers in homebound older adults who are at risk for cognitive decline (Scott et al., 2006). These efforts will add to knowledge of how nutrition can improve cognitive performance in older adults.

Summary of Correlational Research

Overall, correlational research supports the association of cognitive and physical activity, social engagement, and balanced nutrition with maintained cognitive performance in aging, with some reports of conflicting findings. These findings must be interpreted cautiously because correlational research designs fail to establish cause and effect relationships and favor self-selecting samples of “successfully aging” older adults that are not representative of the population at large. Although convenient, cross-sectional designs may also be affected by cohort effects (ways that one generation varies from another), preventing the isolation of true age-related cognitive trends. For example, reduced mathematical abilities of older adults may be a product of limited secondary education in mathematics when they attended school rather than a result of aging.

Although longitudinal studies examining associations between established lifestyle factors and cognition overcome cohort differences to identify cognitive changes, participant attrition frequently results in replacing participants with available healthy older adults, resulting in increasingly biased samples of successfully aging individuals. Variation in performance in different cognitive domains and within cohorts also confounds the identification of age-related changes.

Complex research designs with large samples are also needed to control for multiple factors such as personality, education, occupation, and sensory and physical health that may affect cognition. For example, individuals with higher socioeconomic status can afford higher education that is more cognitively stimulating and logically leads to cognitively challenging professional careers. Professional careers, in turn, support privileged lifestyles that engender well-being. Intensity of cognitive stimulation is difficult to quantify and may vary between individuals and among individuals across activities. Reliance on participant-reported outcome measures is another common practice that may result in inaccuracies and bias.

The research on nutritional intake demonstrates the challenges in correlational research designs. Control of past dietary practices is impossible, and inaccuracies in reports of current dietary intake complicate research in human beings. Thus, nutritional research is frequently conducted on animals where cumulative nutritional practices and other confounding lifestyle factors can be controlled. Human studies have primarily examined cohort effects in international older adult populations with identified nutritional deficiencies or in cross-sectional cohort studies.

The Nun Study (Snowdon et al., 1996) successfully controlled for many factors that potentially influence cognitive aging and concluded that cognitively stimulating activities protect against cognitive decline. Diaries of novice nuns entering the convent in adolescence and their periodic entries across their life spans were analyzed, comparing linguistic complexity, which is an indirect measure of cognition. Nuns entering the convent with lower linguistic complexity typically engaged in less cognitively stimulating roles in the convent and had higher rates of dementia in later years as confirmed on autopsy. Nuns whose initial narratives were more complex were less likely to exhibit dementia, even though plaques and tangles may have been present on autopsy. This study controlled many lifestyle factors such as diet and environment but not the earliest life experiences. The availability of samples that permit this level of control is limited, and future research designs using advanced statistical techniques will be needed to adequately address and control the complex factors that affect cognitive aging.

Correlational research provides evidence of how lifestyle factors affect cognitive performance in aging. However, these effects may only partially determine cognitive performance for older adults. It has been estimated that only 25% of performance differences are due to age (Salthouse, 2006). To clearly establish an effect of cognitive activity on age-related cognitive declines, research must demonstrate differences in cognitive functioning between high-stimulation and low-stimulation groups that increase with age (Salthouse et al., 2002). Despite multiple limitations, research examining associations between naturally occurring or self-selected activities provides a basis for identifying interventions to improve cognitive aging.

Testing Interventions to Optimize Cognitive Aging

On the basis of correlational research, interventions to promote cognitive performance have been developed. These interventions must be tested to establish causal evidence of the effects of cognitive, physical, social, and nutritional interventions on cognitive aging.

Cognitive Interventions

Targeted cognitive interventions are becoming popular, especially memory training interventions. Memory training classes have demonstrated that older adults, like young adults, can improve their performance on cognitive tasks including perceptual discrimination, visual search, recognition, recall, and spatial perception (Kramer et al., 2004). Memory training for healthy older adults typically teaches mnemonic strategies, concentration and attention, relaxation, personal insight, self-monitoring, motivation, feedback, and problem solving that have succeeded in improving memory performance (McDougall, 2000).

Memory training including stress management, health promotion, and memory self-efficacy support has also been tested in older adults in a retirement residence (McDougall, 2000). Improved memory performance and efficacy beliefs were reported postintervention. However, improved memory performance was not associated with improved performance in activities of daily living. Negative correlations of memory with depression suggest memory training may impact other outcomes that improve quality of life.

The Seattle Longitudinal Study (Schaie et al., 2004) identified older adults with existing declines in either inductive reasoning or spatial orientation performance and provided a brief (5 hour) training program designed to improve these skills. Two thirds of participants demonstrated improvement, with 40% returning to a baseline level obtained 14 years earlier. Ongoing effects continued up to 7 years after training. This study supports the value of cognitive training for these specific cognitive abilities that normally decline in aging.

The Advanced Cognitive Training for Independent and Vital Elderly (ACTIVE) clinical trial provided strong evidence of cognitive training effectiveness. Two thousand healthy, community-dwelling older adults were randomly assigned to one of three training groups or to a no-contact control group (Ball et al., 2002). Ten training sessions were provided for verbal episodic memory, inductive reasoning, or processing speed. Immediate posttraining improvements occurred in specific targeted skills that continued for 2 years.

After 5 years of follow up, the ACTIVE study reported the 10 cognitive training sessions followed by 4 booster treatments resulted in both better performance on training-specific domains (memory, reasoning, or processing speed) and less functional decline in instrumental activities of daily living for the inductive reasoning group (Willis et al., 2006). Experimental (versus control) group participants were less likely to experience significant declines in health-related quality of life (Wolinsky et al., 2006). These findings provide direction for ongoing research to test the impact of cognitive interventions on daily lives of older adults.

Physical Activity Interventions

A meta-analysis of 18 clinical trials that examined the impact of fitness interventions on cognition of older adults reported benefits for executive functions, higher level functions that include planning, abstraction, and selection of relevant sensory information (Colcombe & Kramer, 2003; Correa Leite et al., 2001). The analysis examined the type of exercise intervention, duration of training sessions, length of involvement, and cardiopulmonary improvement (i.e., maximal volume of oxygen). Global cognitive improvements were noted in both the experimental and control groups. The strongest effects on executive function were noted for combined aerobic exercise and strength training and for more intensive exercise. Women demonstrated greater gains, possibly due to lower baseline exercise levels (Kramer, Colcombe, McAuley, Scalf, & Erickson, 2005).

A meta-regression analysis of cross-sectional and pretest-posttest exercise intervention research found no differences in cognitive performance for physically fit versus sedentary groups. Relatively small effect sizes of 0.25 were noted for postintervention changes in the pretest-posttest design studies, although postintervention cognitive functions declined, contrary to the hypothesis (Etnier et al., 2006). The analysis indicated that, on average, fitness explained only a limited (8%) amount of the variation in cognition.

Research testing the effects of physical exercise supports benefits of physical activity on preserving cognitive function in aging. However, evidence is limited by selection bias and primary reliance on MMSE scores that may not be sensitive to subtle cognitive changes in older adults.

Social Interventions

On the basis of evidence of the protective effects of social involvement and productive activities on cognition in aging, the Experience Corps program was implemented and tested as a cognitive protective intervention in a randomized clinical trial (Fried et al., 2004). Older adults worked with elementary school students in supportive interactive roles for 15 hours weekly throughout the school year. Physical activity, strength, reported social support networks, and cognitive activity significantly increased for these older adults. This program is a novel start in targeting social engagement interventions to enhance cognitive aging for older adults. These studies support the theory that active involvement with society and engagement in meaningful activity are critical to successful aging.

Nutritional Interventions

Clinical trials focusing specifically on nutrition and cognitive aging are needed to further explore nutrition as a potential intervention to improve cognitive function for older adults. In a 2005 study, a small (N = 67) group of frail older adults with limited or no measurable cognitive decline was included in a 6-month trial testing a daily enriched drink on cognitive measures (Wouters-Wesseling et al., 2005). In the experimental group, short and intermediate memory improved, and plasma B12 levels increased, while homocysteine levels declined.

Evaluation of Intervention Research

Studies that evaluate the outcomes of cognitive interventions have recently been initiated and provide introductory evidence of effectiveness. However, many of these studies fail to isolate specific cognitive domains, and inconsistency in the use of outcome measures makes interpreting results across studies challenging. In addition, other limitations complicate studies testing cognitive interventions.

Most research reports benefits from physical activity on preserving cognitive performance in aging. However, evidence is limited by sample selection bias and primary reliance on outcome measures such as MMSE scores, which may not be sensitive to subtle changes in cognition. Thus, research using rigorous designs with common outcome measures is needed to allow comparison across multiple studies. Increasingly sophisticated research designs using large samples are needed to meet criteria for representative populations as well as to control the multiple factors that may affect cognition in aging.

Implications for Ongoing Research

Research has begun to examine how lifestyle factors, physical and mental activity, social engagement, and nutrition affect cognitive function with advancing age. Overall, these studies provide initial support for the premise that physical and mental activity, social support, and balanced nutrition provide protective effects on cognition in aging. Ongoing research is needed to verify these findings and to identify and isolate specific factors that positively influence cognitive changes that occur with aging. In addition, potential synergistic effects of interventions combining cognitive and physical exercise, social engagement, and nutrition should be explored.

Research designs must move beyond convenient cross-sectional studies to longitudinal trials that can establish causal relationships and control for the numerous confounding factors, such as lifestyle variables, that may impact cognition. Sensitive outcome measures must be identified and used consistently among investigators to enable synthesis of findings from multiple studies. To be meaningful, research must assess whether cognitive gains improve performance of everyday activities, critical for maintaining independence and well-being of older adults. Associated effects of cognitive interventions on improving mood and reducing depression should continue to be explored as secondary outcomes. Clinical trials of interventions will be critical to advance this area of health promotion for an aging population.

To overcome sampling that favors inclusion of the healthiest older adults and fails to reflect a representative population of older adults, additional research is needed to evaluate potential restorative and preventive cognitive interventions for older adults with different cognitive and physical conditions. Testing of interventions must also compare age ranges of older adults to determine optimal timing or critical periods for intervention effectiveness. Future research must more consistently evaluate the impact of cognitive training on activities of daily living and instrumental activities of daily living to identify interventions that promote everyday competence and independence that will make meaningful contributions to the quality of life of aging adults. Analyses comparing the benefits and effectiveness of different cognitive interventions will establish best practices for cognitive health promotion.

Additional research must establish which formats, lengths, and durations of interventions are optimal; whether boosters are necessary to maintain effects; and how to target interventions to individual cognitive levels. Clinical trials will be essential to provide firm causal evidence of cognitive training effectiveness. To be judged effective, interventions must result in differential rates of decline in cognitive function within specific age groups.

Summary and Implications for Practice

Clinicians working with older adults in a variety of settings can incorporate knowledge of the beneficial effects of cognitive activity, physical exercise, social involvement, and nutrition into health promotion for older adults. Older adults reporting cognitive declines (such as memory loss) should undergo cognitive testing. Testing that distinguishes normal versus pathological changes will enable clinicians to reassure most older adults that they are experiencing changes as a normal part of the aging process. Reassurance may alleviate undue anxiety, depression, and social isolation due to fear others will notice cognitive decline.

Anticipatory guidance for older adults should be expanded to focus on cognitive as well as physical health. Within a holistic framework, nurses should routinely counsel patients on the cognitive benefits of social engagement, balanced nutrition, and physical activity, as well as participation in cognitively demanding activities. Families and significant others should be made aware of the cognitive benefits associated with maintaining social connections and engaging in activities with older family members. Counseling should go beyond emphasizing the physical benefits of a balanced, therapeutic diet to explain the added cognitive benefits that may be realized. Knowledge that therapeutic diets prescribed for common chronic conditions such as cardiovascular disease and diabetes may have protective cognitive effects may increase diet adherence in older adults.

Older adults may also be advised to add new cognitive, physical, and social activities and improve nutrition to support successful cognitive aging and improve neuroplasticity (i.e., increased neuronal connections in the brain that increase cognitive reserve, which is the ability to respond successfully to changing environmental stimuli) (Vance & Wright, 2009). Research evidence confirming the benefits of initiating new cognitive health activities is also needed. Nurses are uniquely positioned to advise older adults on general cognitive health promotion lifestyles as well as to prescribe specific cognitive remediation readily available using computer and gaming technologies (Vance, McNees, & Meneses, 2009).

Findings of current research suggest supportive care for older adults can incorporate activities that prevent or limit cognitive disabilities in older adults. Cognitive and physical activities, social engagement, and nutrition to support successful cognitive aging must become integral to care for older adults. Cognitive interventions may support older adults in maintaining self-care as well as cognitive performance into advanced age. For example, community-dwelling older adults who comprehend and follow prescribed medication regimens may be able to extend aging in place compared with those with more substantial cognitive decline.

Potential benefits of cognitively supportive long-term care environments may overcome the negative stigma of moving to assisted living or nursing home settings. Health care workers in institutions caring for older adults must be cognizant of how important physical, cognitive, and social activities and adequate nutrition may be to maintain cognitive abilities for older adults. Programs tailoring activities to the appropriate cognitive levels of the diverse older adults living together in these settings also need to be explored. Ongoing awareness of future research will be important for promoting successful cognitive aging for the growing population of older adults.

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Keypoints

  1. There are some normal reductions in cognitive function in older adults.

  2. Research studies demonstrate associations between cognitive activity and healthy lifestyles with preserved cognitive performance in older adults.

  3. Cognitive training, physical activity, social engagement, and nutrition are all associated with reducing decline in cognitive abilities in aging.

  4. Ongoing research is needed to develop evidence-based interventions to promote successful cognitive aging.

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Authors

Dr. Williams is Associate Professor, Kansas University Medical Center School of Nursing, Kansas City, and Dr. Kemper is Roberts Distinguished Professor, Gerontology Center, University of Kansas, Lawrence, Kansas.

The authors disclose that they have no significant financial interests in any product or class of products discussed directly or indirectly in this activity. The authors are supported by the Building Interdisciplinary Research Careers in Women’s Health (BIRCWH) K-12 Program (K12 HD052027, P. Thomas, PI) at the Kansas University Medical Center School of Medicine.

Address correspondence to Kristine N. Williams, RN, PhD, Associate Professor, Kansas University Medical Center School of Nursing, 3901 Rainbow Boulevard, MS 4043, Kansas City, KS 66160-7502; e-mail: .kwilliams1@kumc.edu

10.3928/02793695-20100331-03

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