The impact of weight loss and low BMI on mortality of nursing home residents – Results from the nutritionDay in nursing homes
Introduction
Weight loss and low body-mass-index (BMI) are well-known risk factors for poor outcomes and increased mortality of older subjects [1], [2], [3], [4], [5], [6], [7], [8], [9], [10], [11], [12], [13], [14], [15], [16], [17], [18]. Both phenomena represent a reduced nutritional state, but their nature is substantially different. Weight loss in older persons is predominantly associated with disease and frailty. A low BMI however, might be a permanent characteristic of a person or a consequence of previous weight loss. To date, it is unclear which of these two factors, weight loss or low BMI, is more important for the prognosis of older subjects and if there is an interference or interaction between them. The fact that subjects with a low BMI are more likely to have lost weight in the past than subjects with a high BMI raises the question of interference between these two factors. In other words, it is possible that weight loss is much more important than a low BMI, and that a low BMI is an overestimated statistical risk factor because numerous subjects with a low BMI may have lost weight before. In fact, there are several studies in older persons indicating that weight loss might be a much more important risk factor than a low BMI [10], [14], [15], [16], [18].
To our knowledge there are few studies that compare the relevance of weight loss and a low BMI in older persons within a single data set [1], [3], [9], [11], [13]. None of these studies analyzed the possible interference and interaction of these two risk factors and some have conflicting results with regard to the prognostic impact of both factors. The nutritionDay in nursing homes (NH) study includes information about weight loss, BMI and mortality. Thus, it is suitable to answer these questions for the population of older nursing home residents.
Section snippets
Methods
The nutritionDay project evaluates disease-related malnutrition in the form of an international, voluntary, annual one-day cross-sectional survey. The survey was first performed in hospitals [4], [19]. Since 2007, the project has been extended to nursing homes [20]. The following analysis is based on all data collected from 2007 to 2012 for the nutritionDay in nursing homes project. With the exception of Japan, only Western developed countries took part. The data from Japan were not used for
Results
Between 2007 and 2012, 369 nursing homes with 26,651 nursing home residents from 17 countries took part in the survey. After the exclusion of participants with incomplete data, especially missing outcomes, and those with age below 65 or repeated participation, 10,298 data sets from 191 nursing homes in 13 countries could be analyzed. Please see Fig. 1 for details about the number and reasons for exclusion of participants and Table 1 for the number of included residents in different years and
Discussion
In our study, both weight loss >5 kg and low BMI <20 kg/m2 were independently associated with increased mortality and showed a risk of comparable magnitude. Even in the adjusted analysis this association with 6-month mortality was robust. However, presenting both features simultaneously increased the mortality risk disproportionally (OR 3.5), due to an interaction between BMI and weight loss. With this finding, our data extend the current knowledge about nutritional risk factors and their
Conclusion
A BMI <20 kg/m2 and weight loss >5 kg in one year are both independent and equally relevant risk factors for the 6-months mortality of nursing home residents aged 65 years or older. If both features are simultaneously present, the mortality risk is disproportionally increased due to an interaction between both features. A low BMI, as well as weight loss, show a strong dose-effect relationship with regard to the 6-month mortality of nursing home residents. On the basis of previous interventional
Financial support
This study was supported by an ESPEN research grant.
Statement of authorship
RW, CS and DV designed the study. RW, CK, CS, UT and DV carried out the analysis. DV, MS, CCS and MH managed the annual survey in nursing homes and the data base. RW and DV wrote the manuscript. All authors read and reviewed the manuscript and approved the final version.
Conflict of interest
None.
Acknowledgments
We would like to thank all participating nursing homes for supporting the nutritionDay.
References (26)
- et al.
Decreased food intake is a risk factor for mortality in hospitalised patients: the nutritionDay survey 2006
Clin Nutr
(2009) - et al.
BMI and all-cause mortality in older adults: a meta-analysis
Am J Clin Nutr
(2014) - et al.
Relationship between BMI and physical performance among older adults
Geriatr Nurs
(2013) - et al.
Obesity can benefit survival-a 9-year prospective study in 1614 Chinese nursing home residents
J Am Med Dir Assoc
(2014) - et al.
Body mass index, dementia, and mortality in the elderly
J Nutr Health Aging
(2008) - et al.
Body mass index as a predictor of all-cause mortality in nursing home residents during a 5-year follow-up
J Am Med Dir Assoc
(2013) - et al.
How nutritional risk is assessed and managed in European hospitals: a survey of 21,007 patients findings from the 2007-2008 cross-sectional nutritionDay survey
Clin Nutr
(2010) - et al.
The first nutritionDay in nursing homes: participation may improve malnutrition awareness
Clin Nutr
(2009) - et al.
ESPEN guidelines on enteral nutrition: geriatrics
Clin Nutr
(2006) - et al.
Body mass index and mortality in institutionalized elderly
J Am Med Dir Assoc
(2011)
Body mass index (BMI), body composition and mortality of nursing home elderly residents
Arch Gerontol Geriatr
Systematic review and meta-analysis of the effects of high protein oral nutritional supplements
Ageing Res Rev
Body mass index, weight loss, and mortality in community-dwelling older adults
J Gerontol A Biol Sci Med Sci
Cited by (54)
Malnutrition significantly affected centenarian prognoses: A prospective study with 5-year follow-up
2023, Clinical Nutrition ESPENThe evaluation of consumed food portions as a screening test for malnutrition in the older people living in a nursing home: A cross-sectional pilot study
2023, Nutrition Clinique et MetabolismeNursing Home Organization Mealtimes and Staff Attitude Toward Nutritional Care: A Multicenter Observational Study
2023, Journal of the American Medical Directors AssociationSarcopenic Dysphagia Is Associated With Mortality in Institutionalized Older Adults
2022, Journal of the American Medical Directors AssociationHungry for more: Low resident social engagement is indirectly associated with poor energy intake and mealtime experience in long-term care homes
2021, AppetiteCitation Excerpt :Despite the recognized importance of meals to nutritional intake in LTC settings, the risk of malnutrition also continues to be a common issue, with prevalence estimates ranging from 40% to 80% of residents at risk or malnourished (Donini et al., 2013; Keller et al., 2017a; Muurinen et al., 2015). Malnutrition and poor food intake have been associated with higher levels of cognitive impairment, functional impairment, lower body mass index (BMI), dysphagia, eating challenges, and higher rates of mortality (Keller et al., 2017a; Wirth et al., 2016). Malnutrition risk is also attributed to multi-level interactions between residents and the larger psychosocial (Keller et al., 2017a; Watkins et al., 2017) and socio-political environments (Lowndes et al., 2015) within LTC homes.