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Meal Delivery Practices Do Not Meet Needs of Alzheimer Patients With Increased Cognitive and Behavioral Difficulties in a Long-term Care Facility

^a Department of Nutritional Sciences, Faculty of Medicine, University of Toronto, Ontario, Canada
^b Kunin-Lunenfeld Applied Research Unit and Department of Food and Nutrition Services, Baycrest Centre for Geriatric Care, Toronto, Ontario, Canada
^c Rotman Research Institute, Baycrest Centre for Geriatric Care, Toronto, Ontario, Canada

Karen W.H. Young, Kunin-Lumenfeld Applied Research Unit, Baycrest Centre for Geriatric Care, 3560 Bathurst Street, Room 728, Toronto, ON, Canada M6A 2E1 E-mail: karen.young{at}utoronto.ca.

Decision Editor: John E. Morley, MB, BCh

	Abstract

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Background. Alterations in circadian rhythms and behavioral difficulties likely impact meal consumption patterns in elderly individuals with probable Alzheimer's disease (AD). Despite these known changes, the profile of meals provided in the institution parallels the needs of younger, free-living, healthy populations. This investigation examined the impact of food delivery patterns on achieved intakes in elderly individuals with probable AD in a long-term care facility and how this relationship changes depending on time of day, body weight status, behavioral function, and cognitive ability.

Methods. Twenty-one consecutive days of investigator-weighed food intake and delivery collections were conducted on 25 elderly individuals with probable AD who maintained the ability to self-feed.

Results. Energy consumed was positively associated with energy delivered for the majority of subjects, although the strength of this relationship varied across subjects and throughout the day. Energy delivered had the greatest impact on energy consumed at breakfast and the least impact at dinner in those with the greatest behavioral difficulties and cognitive impairment. Although those with low body mass indexes (BMIs) were likely to be delivered more energy, the impact of delivery on intakes decreased as energy delivered increased.

Conclusions. Delivering excess energy to patients with poor BMIs likely does not result in increased energy consumption. Behavioral and cognitive deterioration leads to a shift in the time of day that energy delivered has an impact on energy consumption, with the most progressed individuals being most impacted by foods delivered in the morning, suggesting that traditional meal practices are inappropriate for elderly individuals with AD.

UNDERNUTRITION in elderly persons residing in long-term care (LTC) facilities, especially those with Alzheimer's disease (AD), is a key concern because it is a predictor of poor morbidity ⁽¹⁾ and mortality ^{(2) (3)} outcomes in general, and weight loss is associated with increased rates of disease progression in those with AD ⁽³⁾ in particular. Maintaining nutritional status in elderly individuals with AD in LTC is often unsuccessful despite concentrated efforts of health care staff ^{(4) (5) (6)}. The problems encountered are vast, encompassing everything from client characteristics ^{(7) (8) (9)}, to staffing numbers and profiles ⁽¹⁰⁾, to features of the facility in and of itself ⁽¹¹⁾. In addition, the level of cognitive function is a strong predictor of the quality of care provided to a resident, which highlights the difficulties inherent in providing care to this population ⁽¹¹⁾. Although targeted interventions, such as altering food textures ⁽¹²⁾ or providing "finger foods" ⁽¹³⁾, are used, these do not take into account the fact that the patterns of behavior of patients with AD, including disruptions in circadian rhythms ^{(14) (15)} and "sundowning" ⁽¹⁶⁾, progressively change over the course of the disease. That is, despite these known alterations in behavior, the profile of meals provided is consistent with that observed in younger, free-living, healthy populations. Yet, it is highly reasonable to speculate that the behavioral changes apparent in AD markedly impact how and when an individual is likely to eat.

Recently, using accurate methods to assess food intake ⁽¹⁷⁾ and sufficient numbers of days ⁽¹⁸⁾ to capture habitual intake of the individual, we documented that meal-related intakes of elderly individuals with AD demonstrated a marked circadian shift that was highly associated with measures of behavioral function ⁽¹⁹⁾. Notably, peak food consumption occurred in the morning in those with increased behavioral difficulties. Although food provided in LTC is generally in excess of needs ⁽¹⁹⁾, the most energy- and nutrient-dense meals provided are lunch and dinner, consistent with peak consumption times of younger healthy adults ⁽²⁰⁾. However, it is unlikely that such food delivery practices are appropriate for deteriorating AD patients who show disruptions to this circadian pattern. Consequently, we undertook an exploration of the impact of food delivery practices on achieved intakes in cognitively impaired elderly persons residing in an LTC facility to investigate the impact of "normal" meal delivery practices on achieved food intake.

	Methods

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Subjects
All residents of the cognitive impairment units of the Jewish Home for the Aged at the Baycrest Centre for Geriatric Care (Toronto, Canada) were considered for this study. By examining medical histories, only residents with likely AD were included. Although AD diagnoses using National Institute of Neurological and Communicative Disorders–Alzheimer's Disease and Related Disorders Association criteria ⁽²¹⁾ were unavailable, residents were excluded if there was a diagnosis of cognitive impairment secondary to other causes, such as vascular dementia or other neurodegenerative disorders. Subjects also met the following criteria: ⁽¹⁾ maintaining the ability to self-feed or requiring only minimal assistance (e.g., tray set-up; residents requiring higher levels of feeding assistance were excluded to enable an examination of free-eating patterns, uncontaminated by the role of a feeding assistant) and ⁽²⁾ absence of other diseases requiring nutritional intervention (e.g., types 1 or 2 diabetes mellitus). Twenty-five individuals (3 men and 22 women; mean age, 85.9 ± 7.6 years; for further subject details see Ref. 19), comprising approximately a 60% participation rate of eligible subjects, were included. Following protocol approval by the Baycrest ethics committee, informed consent was obtained from the family or legal guardian.

Cognitive and Behavioral Assessments
Cognitive status was determined using the Mini-Mental State Examination (MMSE) ⁽²²⁾, and behavioral function was assessed by the London Psychogeriatric Rating Scale (LPRS) ⁽²³⁾, using standard protocols. A higher score on the LPRS indicates greater disability and consists of four subscales: Mental Disorganization/Confusion (MENT), Physical Disability (PD), Socially Irritating Behavior (SIB), and Disengagement (DIS).

Food Intake Collection
The objective of this study was to examine the impact of "traditional" meal delivery practices exercised in an LTC environment. Consequently, no interventions were applied; rather, food delivery and intake were assessed against the backdrop of each subject's current clinical care. Twenty-one consecutive days of investigator-weighed food intake and delivery were monitored on each subject (mean values are presented in Table 1 ). Although subjects were unaware of the study, this could not be masked from the clinical staff. Nevertheless, the extended period of data collection likely minimized the overall impact of our presence on routine practice.

Although the consumption of snacks was measured ⁽¹⁹⁾, snacks were not included in these analyses because, unlike the meals, their delivery was not uniform. Snacks were not provided if the client was not hungry, was sleeping, or was off the unit at the time of presentation; in contrast, clients would be brought to the unit for all meals. Also, although meals generally provided food in excess, the snacks were smaller and were entirely consumed when given. It was felt that this all-or-none phenomenon (100% or 0% consumption) with the snacks would not facilitate the broader understanding of the impact of delivery on achieved intake. The role of snacks and their impact on subsequent meals is currently under investigation (manuscript in preparation).

Statistics
Regression analyses using SAS for Windows, version 6.12 (SAS Institute, Inc, Cary, NC), were conducted to examine the relationship between energy delivered and energy consumed for daily meal totals (breakfast + lunch + dinner) and independently for each meal. Analyses conducted at the level of the individual indicated autocorrelation among the residuals for some residents (mostly positive autocorrelation, i.e., high intake on one day was generally followed by high intake on the subsequent day). Therefore, an additional independent variable was inserted into the model "energy consumed at t - 1" to account for the impact of the previous day's consumption on achieved intake, for all meals and daily total intake. These regression analyses describe the impact of energy delivered on energy consumed, and are represented by the parameter estimate (b value). The b values varied tremendously across individual subjects.

To determine what subject characteristics best described whether an individual's intake was highly impacted by energy delivery (high b value) or showed little to no relationship to delivery (b value close to 0), the b values for each subject were regressed against the body mass index (BMI), and the MMSE, LPRS, and the LPRS subscales, using the reciprocal of the variance of individual b values as a weighting variable. For presentation purposes, weighted regression lines have been superimposed upon unweighted values for all figures.

	Results

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Relationship Between Energy Delivered and Consumed: Group Analysis Versus the Individual
To determine whether the amount of energy delivered to subjects had an impact on achieved intakes, the relationship between delivery and consumption was examined. When data were analyzed at the group level (i.e., each subject's 21-day mean intake vs mean delivery), no relationship was found, implying that an increased provision of food/energy did not result in increased consumption ( Fig. 1, left panel). Nevertheless, analysis of mean data likely did not have fine enough resolution to detect what was actually occurring at the level of the individual. Indeed, when the total energy consumed versus delivered was analyzed, with observations on 21 days within each subject ( Fig. 1, right panel), the energy consumed increased as the delivered energy increased (p < .001, b value = 0.50). Thus, in contrast to the plot containing mean data only, this suggests that there were many individuals whose intakes were highly impacted by energy delivery.

View larger version (17K): [in this window] [in a new window]   Figure 1. Relationship between total energy delivered and total energy consumed using mean data (left) and using all data for each subject superimposed on mean data (right).

Conversely, negative relationships between mean energy delivered and the b value (meal total: p < .001, r² = .49; breakfast: p = .001, r² = .36; lunch: p = .005, r² = .30; dinner: p = .001, r² = .37) indicate that individuals who were delivered the greatest amount of energy tended to have the weakest association between delivery and consumption. Thus, increasing the amount of energy delivered to an individual likely decreases the impact of delivery on achieved intakes. It is highly likely that those individuals who were receiving the most energy were delivered these high amounts because of poor body weight status and/or because their intake levels had decreased. If this is true, these analyses would suggest that providing more foods at the existing mealtimes is unlikely to promote increased consumption levels in individuals whose intakes are already compromised.

Associations With Body Weight Status
Inverse associations between BMI and total energy delivered (p = .015, r² = .23), as well as energy delivered at breakfast (p = .014, r² = .23), confirm that more energy was delivered to individuals with poor body weight status relative to those with high BMIs (lunch [ p = .074, r² = .13] and dinner [ p = .105, r² = .11] associations showed borderline significance). Further, an examination of the relationships between BMI and the b value ( Fig. 2) shows that the intakes of those with poor BMIs were the least impacted by energy delivery, while the intakes of those with higher BMIs tended to be highly impacted by energy delivery. Thus, providing more foods at the existing mealtimes is unlikely to result in increased food intake in those with high-risk BMIs.

View larger version (26K): [in this window] [in a new window]   Figure 2. Relationship between body mass index (BMI) and b value (N = 25): A, meal total: p = .060, r2 = .15; B, breakfast: p = .022, r2 = .21; C, lunch: p = .016, r2 = .23; and D, dinner: p = .001, r2 = .37. The weighted regressed line is superimposed on unweighted data points.

View larger version (26K): [in this window] [in a new window]   Figure 3. Relationship between the London Psychogeriatric Rating Scale (LPRS) and b value (N = 25): A, meal total: p = .588, r2 = .01; B, breakfast: p = .022, r2 = .21; C, lunch: p = .655, r2 = .01; and D, dinner: p = .038, r2 = .17. The weighted regressed line is superimposed on unweighted data points.

	Discussion

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The results of this study question the wisdom of current meal delivery practices exercised in LTC facilities and suggest that they should be redesigned to optimize the actual eating behaviors of elderly persons with AD to better meet the nutritional needs of this at-risk group. That is, the traditional practice of providing the least energy-dense meal at breakfast and the most energy-dense meals for lunch and dinner is counter to the pattern of responsiveness to foods exhibited by those with greater behavioral and cognitive disabilities. Furthermore, providing excess energy (food) at a single meal to those with poor body weight status is likely an ineffective means to enhance intake.

Peak energy consumption occurs at breakfast in elderly persons with AD who exhibit increased behavioral difficulties ⁽¹⁹⁾. This is consistent with the observation of increased confusion or agitation in the afternoon or early evening, termed "sundowning" ⁽¹⁶⁾. Despite this, meal programs in LTC facilities parallel the needs of healthy young adults whose peak mealtimes tend to occur at noontime and early evening ⁽²⁰⁾. By maintaining a traditional profile of meals, the most energy- and nutrient-dense meals are given when elderly persons with advanced AD are least likely to eat. Substantiating the ineffectiveness of this practice, this investigation showed that energy consumption levels in individuals with the greatest behavioral difficulties and/or cognitive disability were the most impacted by energy delivered at breakfast and the least impacted by dinner. These data suggest that disruptions in the mechanisms that regulate appetite and intake are time dependent, such that appetites appear to be stimulated in the morning and are highly responsive to increased energy delivery at this time, but become depressed as the day advances, such that the more deteriorated individuals become nonresponsive to the food delivered at dinner. Consequently, delivering the most nutrients and energy at lunch and dinner is an ineffectual, highly wasteful practice, since these meals are not being consumed by those with increased cognitive and behavioral difficulties. Rather, the focus of food delivery should be during the morning when residents at the advanced stages of decline are the most responsive to the food provided.

In addition, the practice of providing additional foods at each meal to stimulate intake in those with poor BMIs is also likely an ineffectual, or possibly harmful, approach. Although there is an overall positive association between energy consumed and energy available, it appears that increasing food delivery at any of the meals above normal levels is unlikely to increase intake, because the impact of delivery on intakes becomes weaker as the amount of energy delivered increases. That is, intakes become less responsive to delivery as delivery increases. This was especially evident in those with the lowest BMIs who were delivered the highest levels of energy, even though their intakes were the least impacted by the energy delivered. Many factors can account for this. For example, providing many foods at once may cause overstimulation leading to agitation and thus decreased food consumption. In addition, excess delivery of foods tends to occur later in the day when these individuals are likely to be less cognitively alert and the least responsive to the foods provided. Thus, although individuals with low BMIs were likely not eating well before any interventions were implemented, increasing food delivered at lunch and/or dinner is unlikely to enhance food intake, and the provision of too many foods may in fact result in decreased energy consumption.

Although the current study implicates behavioral and functional deterioration in driving intake patterns and their association with food delivery, other factors deserve attention. For example, early satiety and weight loss have been associated with infection and the use of drugs in elderly persons ^{(25) (26) (27)}, and it could be argued that the subjects with more advanced disease would also be more likely to be receiving multiple medications and/or be more susceptible to infection. Although these issues were not factored into the analyses, they are most likely to result in an overall decrease in intake but are unlikely, in and of themselves, to account for the observed circadian pattern of responsiveness to food delivery.

Methods of data analysis must also be addressed, since the type of statistical analyses performed had profound effects on the results. Clearly, to understand the true nature of the relationship between energy consumed and delivered, the analyses must have adequate resolution to acquire information at the level of the individual rather than the group. Using mean data to determine the association between energy consumed and delivered falsely suggested that there was no relationship and that, as energy delivery increased, compensation likely occurred such that the residents consumed a smaller percentage of their food. However, including within-subject variability in the analyses showed that there was a positive association between energy consumed and delivered, suggesting that compensation may not occur in all individuals in this population and that the regulatory mechanisms that would normally signal satiety may not be properly functioning.

In summary, this study has demonstrated the need to redesign current food delivery programs in LTC facilities to better meet the needs of the most vulnerable elderly persons with AD: those with increased behavioral difficulties, high cognitive impairment, and/or low body weight status. Although caregivers attempt to maintain a "normal" feeding pattern, it must be recognized that these elderly individuals no longer exhibit the same intake patterns as healthy young adults. To optimize the nutritional status of these individuals, efforts must be directed toward the morning meal, when those with behavioral difficulties and/or increased cognitive impairment are the most responsive to the foods provided. Further, more effective means of stimulating food intake in those with low BMIs, rather than increasing the amount of food delivered, need to be developed. Future studies that replicate these findings while accounting for the use of anorectic drugs and infection, as well as studies in elderly persons with AD at other stages of the disease, are needed.

	Acknowledgments

 
This research was supported by grants from the Program in Food Safety and the Canadian Institute of Health Research (CIHR). Karen Young was the recipient of a University of Toronto Open Fellowship, an Ontario Graduate Scholarship in Science and Technology, and a K.M. Hunter/CIHR Research Award.

Received December 15, 2000

Accepted January 26, 2001

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