Malnutrition and cognitive impairment among people aged 60 years and above living in regular housing or in special housing in Sweden: a population-based cohort study
- Faculty of Medicine and Health Sciences Centre for Research and Innovation in Care (CRIC), University of Antwerp, Wilrijk, Belgium
- Correspondence to Bart Geurden
University of Antwerp, Universiteitsplein 1, Wilrijk 2610, Belgium;
Implications for research and practice
Implications for nursing practice of this research:
■ Malnutrition is not restricted to institutionalised older people with cognitive impairment. Those with cognitive impairment living in regular housing also have an increased risk of malnutrition.
■ Impaired cognitive ability rather than impaired functional ability is associated with malnutrition regardless of housing and living arrangement.
■ Moderate or severe cognitive impairment is associated with malnutrition rather than mild cognitive impairment.
Implications for nursing research in the light of this study:
■ Research to clarify the complex cause-effect relationship between environmental factors and malnutrition needs much larger study populations.
■ Malnutrition should be more precisely defined and measured with a validated tool.
■ Home should be a safe and protective environment for older people therefore, more research should be dedicated to the nutritional status of people with different types and grades of dementia living at home.
Fagerström and colleagues studied malnutrition and cognitive impairment among people ≥60 years living in regular housing and special housing in Sweden. Malnutrition is a common problem especially in older people, with a prevalence from 1% in community-dwelling healthy older people1 to 33% in hospitalised older people.2 Causes of malnutrition are deficiencies in dietary intake, digestion and absorption, excretion and alterations in metabolic requirements related to specific conditions. Malnutrition in older people is also associated with reduced functional and cognitive ability. However, it is unclear if the relationship between malnutrition and impaired cognitive ability is connected to living arrangements.
Demographic data were collected from questionnaires. A body mass index (BMI)≤23 kg/m2 was considered to indicate malnutrition. A Mini-Mental State Examination score of 20–24 was considered to indicate mild cognitive impairment and all scores <20 were grouped and described as a moderate or severe cognitive impairment. The rating scale ‘Activity of Daily Living’ classified the population into five categories: excellent functional ability and mild, moderate, severe and total impairment of functional ability.
The sample (n=1402) consisted of 58.3% of women. Mean age was 76.7 (SD 10.2) years. The women lived alone more often and suffered more frequently from impaired functional ability (p<0.001). There was no significant difference between genders in respect to BMI (p=0.39) but malnutrition occurred significantly more in woman (p<0.001). In regular housing, 15.7% and in special housing 23.6% had malnutrition. People living alone and cohabiting in regular housing, 19% and 13.5% had malnutrition, respectively.
A slight correlation between cognition and nutritional status (rs=0.08, p<0.01) was found in the total sample. When focusing on housing arrangement, the correlations between cognitive ability and nutritional status varied (rs=0.06–0.44, p<0.05).
In multiple logistic regression analyses, malnutrition is not associated with impaired functional ability in any of the models but rather with impaired cognitive ability. The dimensions of the associations were different depending on housing and living arrangement.
Prevalence of malnutrition in community-dwelling older people with cognitive impairments are known.3 But Fagerström and colleagues4 are to be congratulated on their efforts to analyse the relation between housing arrangement and malnutrition. Research to clarify the complex cause-effect relationship between environmental factors and malnutrition is needed to design effective prevention for malnutrition, especially in the growing population of community-dwelling older people. Unlike similar studies,5 the authors used BMI to define malnutrition. As a consequence, older people with a BMI of 22 kg/m2 without a history of weight loss together with older people with a BMI of ≥24 but with a recent loss of weight are to be considered as false-positive and false-negative results. Using, for example, the mini nutritional assessment will prevent such bias. Furthermore, this is a single national study with some small subsamples. Nevertheless, these findings are important and invite further research.