NUTRITIONAL RISK FACTORS FOR INSTITUTIONAL PLACEMENT IN ALZHEIMER S DISEASE AFTER ONE YEAR FOLLOW-UP

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1 NUTRITIONAL RISK FACTORS FOR INSTITUTIONAL PLACEMENT IN ALZHEIMER S DISEASE AFTER ONE YEAR FOLLOW-UP S. ANDRIEU*, **, W. REYNISH*, F. NOURHASHEMI*, **, P.J. OUSSET*, H. GRANDJEAN**, A. GRAND**, J.L. ALBAREDE*, B. VELLAS* * Department of Internal Medicine and Clinical Gerontology, Alzheimer Center, 170 chemin de Casselardit, Toulouse. ** INSERM U558, laboratoire d épidémiologie, Faculté de Médecine, Université de Toulouse, 37 allées Jules Guesdes, Toulouse Cedex, France. Correspondence: Dr Sandrine Andrieu, unité INSERM 558, laboratoire d épidémiologie, Faculté de Médecine, 37 allées Jules Guesdes, Toulouse Cedex, France, tel (33) , fax (33) , sandrieu@cict.fr Abstract: Amongst factors associated with the institutional placement of elderly people with dementia, there has been little study of those related to malnutrition. We followed a cohort of 318 individuals with Alzheimer s disease (AD). Patients, who were all living at home at the start of the study were recruited from the outpatient service of a hospital unit specialising in AD. After one year, 20% of the patients had moved into institutional care. Multivariate analysis showed that a Mini nutritional Assessment score (MNA) of less than 25.5 (median score of the sample) and overeating behavioural problems (p=0.006) were risk factors for institutional placement. Nutritional problems are reversible and patients with a low MNA score could benefit from a thorough geriatric assessment, in order to slow or prevent institutional placement. Key words: Nutrition, elderly, aging Introduction Malnutrition occurs frequently among elderly individuals. It has been shown that elderly people with loss of autonomy may have more nutritional problems than healthy elderly people (1). Weight loss is a particular problem amongst patients with Alzheimer s disease, in which it occurs in the early stages of the disease, or even before diagnosis (2). Some studies suggest that weight loss of more than 4% of initial body weight over one year predicts an increased risk of mortality in patients with dementia (3). Previous studies of elderly, community-dwelling adults have shown that malnutrition, defined using biological markers such as serum albumin (4), or a low MNA score (5) was associated with increased risk of mortality. Recently, similar results have also been observed in patients with cognitive deficits(6). Certain markers of malnutrition are associated with increased frailty in elderly people. In a community-dwelling elderly population, extremes of BMI were predictive of a loss of functional autonomy (7). Also in a recently hospitalised sample of patients, poor nutritional status tended to increase the length of hospital stay, and the risk of early post-discharge rehospitalisation as well as placement in an institution(8-10). Finally a recent study has shown that in a population of elderly people living at home with help from home-care services who had neither cognitive problems nor major depression, weight loss of more than 5 kg was an independent risk factor for institutional placement (11). The object of our study was to assess the effect of nutritional status on the risk of institutional placement in an elderly population of 318 patients with Alzheimer s Disease. Materials and Methods The study population consisted of all Alzheimer s Disease patients, living in a region of Southern France, who had been followed in ELSA (Etude Longitudinal de Suivi d Alzheimer) for at least one year. ELSA is a longitudinal study of patients with a diagnosis of Alzheimer s Disease according to NINCDS-ADRDA criteria (12). Patients have a comprehensive objective six-monthly assessment to evaluate various cognitive and non-cognitive parameters. All subjects in the study who had been followed for at least one year, and were living in their own homes at the start of the study were included in this analysis. Data collection The data describing patient characteristics were collected at the initial visit. Data from the first two follow-up visits (at 6 months and 12 months) were analysed regarding institutional placement. Evaluation of Nutritional Status At the initial visit, nutritional status was assessed using the Mini-Nutritional Assessment (13), Body Mass Index and serum albumin (g/l). 113

2 NUTRITIONAL RISK FACTORS Other Characteristics studied The following data were collected for all patients in the study: Sociodemographic data including age, sex, educational level (level below or equal to school certificate, baccalaureate or University degree) and habitation (living alone or not). Physical incapacity was measured at inclusion using the Katz activities of daily living (ADL) scale (14), which assesses behavioural levels of six sociobiological functions, namely, bathing, dressing, toileting, mobility, continence, and feeding. The overall score gives a measure of autonomy between 0 (completely dependant) and 6. The 8 item IADL scale (15) was used to measure instrumental activities of daily living (IADL), scoring the subjects ability to use the telephone, transport, do the shopping, prepare meals, do the housework, do the laundry, and to manage their medications and money. It is scored between 0 and 8 with a higher score representing a greater degree of autonomy. Cognitive function was evaluated using Folstein s Mini Mental Status Examination (16). Behavioural problems were assessed with the Cohen- Mansfield scale (17), for which the carer rates the frequencies of 13 specific types of behaviour. The overall score out of a maximum of 91 quantifies behavioural problems with higher scores corresponding to more problems. Mood was assessed using the Cornell scale for depression in dementia (18). On this scale higher scores correspond to more marked depression. Primary Endpoint At one year the primary endpoint was institutionalisation. For the purposes of this analysis, sheltered housing and moving in with a care-family were considered as institutional placement. Statistical analysis We analysed the relationship between certain baseline patient characteristics and institutional placement. Subjects who were lost to follow-up for some other reason were not included in this analysis. A bivariate analysis was performed with comparison of means for quantitative variables (by analysis of variance) and comparison of frequency distributions for qualitative variables (using the Chi squared test or Fisher s exact test). Certain quantitative variables such as BMI were first transformed so as to have a normal distribution. When a simple transformation was not possible we used the medians of the quantitative variables. All analyses were carried out on STATA software. Two multivariate analyses were performed and a logistic regression with institutional placement as the dependant variable. The first analysis only included nutritional independant variables. For the final model, other patientspecific variables were added in a stepwise analysis. The validity of the model was assessed using the Hosmer and Lemeshow test. Results Sociodemographic characteristics of the patients (n=318) The mean (SD) age at inclusion was identical for men and women, being 75.4 (7) years with a range from 45 to 89 years. 67.2% of the population were women. 22% of the patients lived alone at home. The majority of the remainder lived with the spouses, while a few lived with another family member. Alzheimer s Disease characteristics studied 38.7% (n=122) of the patients had a family history of Alzheimer s Disease, while in 12.4% (n=39) it was uncertain. The length of time between disease onset and inclusion in the study was less than or equal to a year in 53.5% of cases, and less than or equal to three years in 94.3% of cases. The mean (SD) MMSE score was 17.4 (5.9), with 84.5% of the subjects having a score less than or equal to 23. Almost 93% of patients had behavioural problems reported by their carers and the median score on the Cohen-Mansfield scale was 22 with a range of 13 to 51. Nutritional parameters Mean (SD) MNA score was 24.9 (2.5) with only two subjects having a score under 17, consistent with proteinenergy malnutrition. Mean (SD) BMI was 24.4 (3.8) with 10.3% of subjects having a BMI less than or equal to 20. Mean (SD) serum albumin was 43.5 (4.5). Only 12.4% of patients needed any help to feed themselves, of whom most only needed partial help, but 30.4% needed accompanying for shopping and 24.9% were completely unable to do their shopping. Carers reported eating behavioural problems in 11.9 % of subjects. These were divided into a tendency to overeat (7.1%), anorexia (4.8%) and risk of ingesting toxic substances (1.9%) Patient characteristics according to place of residence at 1 year of follow-up are presented in table 1. At one year follow-up data were unavailable for 17.2% (n=66) of the initial population (n=384). The most common reason (n=39) was a failure to attend the one year follow-up visit because family members refusal to continue. Other reasons included moving to another town and absenteeisme. Only 5 patients were truly untraceable. These patients were excluded from the analysis. Comparison of the baseline characteristics of these patients with those who remained in the study showed no differences in nutritional parameters (MNA score, serum albumin or BMI), severity of Alzheimer s disease (MMSE, behavioural problems, Reisberg scale, ADL and IADL). Two parameters did differ between the two groups: subjects who left the study were more likely to have a child as their main carer, rather than another person (20.6% versus 12.3%; p=0.025) and were more likely to have cardiovascular disorders such as arterial hypertension or ventricular failure. Among the 318 subjects remaining in the analysis, 64 (20.1%) had entered an institution at one year while 254 remained at home. Of these 11 died during the year at home and were included in the analysis. 114

3 Nutritional status At the start of the study, only two subjects had an MNA score below 17, consistent with very poor nutritional status, while 19% (n=49) had scores between 17 and 23.5, and therefore at risk of malnutrition. For the statistical analysis, as so few subjects had a low MNA score, the median MNA score was used, taking the ditribution of this variable into account. ie the group of patients with MNA scores below 25.5 was compared with those with MNA scores above 25.5.The results showed that 21.2% of cases in the low MNA group and 10% of cases in the high MNA group were institutionalised at one year (p = 0.015). The mean BMI for the two groups was identical (p= 0.88). Serum albumin was lower in those patients who were institutionalised than those who stayed at home (42.8 c/l versus 44.2g/l; p=0.02). 20% of the study population had dental problems, but there was no difference in frequency between the two groups. However feeding behavioural problems such as overeating or risk of ingesting a toxic substance, and to a lesser degree, anorexia, were more frequent in the institutionalised group (p= 0.004, p=0.001 and p=0.2 respectively). Autonomy for activities of daily living, evaluated by the ADL and IADL scales was more often reduced for subjects institutionalised at one year compared to those who remained in their own homes. Regarding independence in feeding behaviour, it could be argued that subjects with an MNA score below the median more often have problems feeding themselves, doing their shopping and preparing meals. (see table 2) To find out which nutritional parameters influenced institutional placement, the following were included in the logistic regression model after adjustment for age and gender: MNA score (above or below the median), serum albumin concentration, the presence of eating behavioural problems. This analysis showed that MNA and the presence of overeating behavioural problems were significantly associated with institutional placement (Table 3). Table 1 Baseline descriptive characteristics of the population by area of residence at the end of one year follow up. Results of bivariate analysis. Living in the Institutionalised P community n=254 n=64 Sociodemographic charateristics Age in years 75.0 (± 7.0) 76.9 (± 6.6) 0.05 Female gender (%) Living alone (%) Professional carers (%) Nutritional Parameters MNA (%) Score below median 21,2 10, BMI Serum albumin (g/l) Dental problems (%) Eating behaviour problems - Overeating (%) Anorexia (%) Risk of ingesting toxic substance (%) Dementia Severity MMSE Score <0.001 Cornell Score Cohen Score Pacing (%) <0.001 Autonomy Problem with at least one item of ADL (%) Problem with at least one item of IADL (%) Ability to feed self (%) Eats without help Requires some help Requires moderate to complete help Ability to prepare meals (%) Prepares and serves meals independently Prepares meal if given foodstuffs Can reheat pre-prepared meal Incapable of preparing or serving food Ability to do shopping (%) Entirely independent Manages to do some but not all shopping Needs accompanying Unable of doing shopping

4 NUTRITIONAL RISK FACTORS Table 2 Baseline descriptive characteristics of the population by the MNA score. Results of bivariate analysis. MNA MNA P > 25.5 < 25.5 n=120 n=137 Ability to feed self (%) Eats without help Requires some help Requires moderate to complete help Ability to prepare meals (%) Prepares and serves meals independently Prepares meal if given foodstuffs Can reheat pre-prepared meal Incapable of preparing or serving food Ability to do shopping (%) Entirely independent Manages to do some but not all shopping Needs accompanying Incapable of doing shopping Dementia severity MMS score 19.6 (5.9) 16.7 (5.4) <0.001 Cohen score 22.3 (7.2) 23.5 (7.1) Pacing (%) Problem with at least one item of ADL (%) <0.001 Problem with at least one item of IADL (%) Table 3 Nutritional factors associated with institutional placement at one year, adjusted for age and gender. Results of the multivariate analysis. (n=254). OR IC à 95% P MNA Overeating To study the effect of nutritional markers compared to other factors related to dementia severity, the two nutritional markers significant in the first analysis, were included in a model with other factors shown to be associated with institutionalisation in the bivariate analysis. These were cognitive level (MMSE), behavioural trouble score (Cohen Mansfield scale), pacing and loss of autonomy for at least one item of ADL or IADL. After adjustment, the following were shown to be independently associated with institutional placement: a low (below the median) MNA score, the presence of overeating behavioural problems. Male sex and pacing were associated but the did not quite reach the level of statistical significance. Table 4 Factors associated with institutionalisation at one year after adjustment for age. Results of the multivariate analysis (n=247). OR IC à 95% P MNA Overeating Pacing Age Female gender Discussion This study shows that the risk of placement in an institution in the short term for Alzheimer s Disease sufferers, is related to nutritional status, as measured by the Mini Nutritional Assessment. The rate of institutionalisation observed in this study is comparable to rates observed in studies of samples of patients with dementia selected from specialist hospital dementia services. These rates vary from 20 to 28% (19-23). Many studies have looked at risk factors for institutionalisation but few have previously explored the effect of nutritional status (10, 11, 24, 25). Some authors have shown an association between certain parameters which may have a bearing on nutritional status and institutional placement. These include inability to do one s own shopping, recent weight loss and scores based on the Body Mass Index or brachial circumference. These studies differ from ours in the characteristics of the subjects studied, but also methodologically, in that they are either cross-sectional or longitudinal with a much longer period of follow up. One comparable study finds no association between malnutrition and short term institutional placement, however this study does not give a precise definition of malnutrition (25). To our knowledge, no previous study has looked at an association between nutritional status, as evaluated by the MNA, and risk of nutritional placement. In our study, the MNA score was associated with cognitive dysfunction, as evaluated by the MMSE, as well as incapacity to perform ADL, both of which have been shown to be important risk factors for institutional placement (26-28). The strength of the MNA is that it comprises elements relating to the elderly person s life style as well as objective clinical parameters. 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