With the European population growing older, the challenge is to keep an increasing number of seniors across all European countries healthy and active. In Europe, between 13.5 % and 29.7 % of older adults living at home are malnourished or at risk of protein energy malnutrition. PROMISS aims to better understand and ultimately prevent protein energy malnutrition in seniors. Thereby, PROMISS will contribute to improve active and healthy ageing.
Nutrition for healthy ageing
Health ABC: Health, Aging and Body Composition Study
PROMISS and the Health ABC Study
The Health, Aging and Body Composition (Health ABC) Study is one of the longitudinal studies contributing to work package 1 of PROMISS. The Health ABC cohort consists of 3,075 black and white US older adults aged 70 years and over, who were generally well-functioning at baseline. The main focus of the Health ABC study is to determine risk factors for functional decline and loss of independence in healthier older people.
Since the start of PROMISS in April 2016, several researchers have used the Health ABC data to investigate associations of dietary intake with appetite, malnutrition and mobility limitation in US older adults. In the first paper, entitled “Protein intake and mobility limitation in community-dwelling older adults: the Health ABC Study”, it was hypothesized that older adults with low protein intake would have a greater risk of developing mobility limitations than those with higher protein intake. The results confirmed the hypothesis: it was shown that older adults with a lower protein intake (<0.7 and 0.7-<1.0 kg/kg body weight/d) had a higher risk of developing mobility limitations in the following 6 years compared to older adults with the highest protein intake (≥1.0 g/kg body weight/d).
The second paper, entitled “Poor appetite and dietary intake in community-dwelling older adults”, focused on differences in food intake in community-dwelling older adults with different appetite levels. This study showed that 21.8% of the participants had a poor appetite. Those participants consumed less protein, dietary fiber, whole grains, fruits and vegetables, but consumed more dairy foods, fats, sweets and sodas compared to the participants with a very good appetite.
The association between diet quality and protein-energy malnutrition was investigated in the third paper, entitled “Prospective associations of poor diet quality with long-term incidence of protein-energy malnutrition in community-dwelling older adults: the Health, Aging and Body Composition Study.” This study showed that the majority of the participants consumed a diet of insufficient quality and that 40% of the participants had a protein intake below the recommended daily intake. Furthermore, in 4 years almost 25% of the participants developed protein-energy malnutrition. It was observed that a higher protein intake may reduce the risk of developing persistent protein-energy malnutrition.
Researchers of work package 1 of PROMISS are currently working on a two other studies by using data from the Health ABC Study. In the first one, those data will be used in a multi-cohort paper on determining the prevalence of low protein intake in community-dwelling older adults. In a second paper, the association between poor diet quality and the risk of developing frailty in (initially non-frail) community-dwelling older adults will be investigated.
The HANC Study: Healthy Ageing Network of Competence in Southern Denmark – Northern Schleswig-Holstein
Combining physical activity and functional tasks in older age
Part of the work carried out in the PROMISS project is based on the HANC study. HANC is an ongoing large-scale European project between 8 Danish and German entities. Currently, 560 older adults (average 82.7 years old) with mobility impairment have a baseline assessment from 12 different domains (e.g. physical activity and sedentariness, sleep, muscle function, environmental characteristics). Assessment involve 7-day measurement by wrist-worn accelerometers, which contributes especially to PROMISS WP2 on reporting physical activity, sedentary behavior in older adults and can be compared with other cohorts in the PROMISS consortium.
Li-Tang Tsai and Paolo Caserotti, from the University of Southern Denmark, have reported preliminary results of accelerometer data from 2 cohorts: data from HANC suggested that older people with a combination of low activity count and low variability of activity throughout the week (meaning their activity level is stable throughout the weak) performed worst in functional tasks (SPPB: walking speed, chair stand, balance test) while those with high activity count and high variability of activity throughout the week performed best in the same tasks.
The team is currently working on a manuscript which will describe and compare accelerometer data from 5 cohorts within PROMISS consortium. This work will be an input to the symposium on “The impact of appetite, low protein, and physical activity on function: the PROMISS study” in the 24th Nordic Congress of Gerontology on 2-4 May in Oslo, reporting on “Associations between accelerometer-assessed physical activity, sedentary behavior, and handgrip strength among older adults across Europe and USA”.
Influencing or not influencing food intake: some considerations
Kristina S. Fluitman, Madelief Wijdeveld, Max Nieuwdorp, Richard G IJzerman Gut.
2018 Jan 30. pii: gutjnl-2017-315543. doi: 10.1136/gutjnl-2017-315543. [Epub ahead of print]
Various issues influence our appetite and metabolism, and gut bacteria have a role to play in there. A previous research project focused on one of the substances made by gut bacteria, namely butyrate, which is thought to improve body weight, appetite, and glucose- and fat-metabolism.
The project demonstrated in mice that most effects of butyrate on body weight and metabolism were actually not caused by butyrate directly. Rather, butyrate caused a decrease in appetite and food intake, which in turn caused the improvements in body weight and metabolism. Because of its effects on appetite, the researchers concluded that butyrate might potentially be used as weight-losing drug.
PROMISS would like more research to be carried out. The fact that that project was performed in mice, not in human beings, cannot make us jump to the conclusions that their results would be similar in human beings. The PROMISS experience is that effects in mice (promising as they might be) are often not as remarkable in humans. Furthermore, even if butyrate would work as effective in humans as it does in mice, we think that it might only work in specific individuals.
Read the whole scientific paper here.