Purpose To investigate the longitudinal association between the macronutrient composition of the diet and frailty. Methods Data were obtained from 5205 Dutch middle-aged and older adults participating in the Rotterdam Study. Frailty was measured using a frailty index based on the accumulation of 38 health-related deficits, score between 0 and 100, and a higher score indicating more frailty. Frailty was assessed at baseline and 11 years later (range of 23 years). Macronutrient intake was assessed using food-frequency questionnaires. The association between macronutrients and frailty over time was evaluated using multivariable linear regression, adjusted for the frailty index at baseline, energy intake, and other relevant confounders. All analyses were performed in strata of BMI. Results Median frailty index score was 13.8 points (IQR 9.6; 19.1) at baseline and increased by a median of 2.3 points (IQR − 2.0; 7.6) after 11 years. Overall, we found no significant associations between intake of carbohydrates or fat and frailty over time. We did observe a significant positive association between an iso-energetic intake of 10 g protein and frailty over time (β 0.31 (95% CI 0.06; 0.55)) which was mainly driven by animal protein (β 0.31 (95% CI 0.07; 0.56)). It did not depend on whether it was substituted fat or carbohydrates. Conclusions Our findings suggest that a reduction in the intake of animal protein may improve the overall health status over time in a relatively healthy population. More research is needed on the optimal macronutrient composition of the diet and frailty in more vulnerable populations.

ObjectiveThe recognition of dementia as a multifactorial disorder encourages the exploration of new pathways to understand its origins. Social health might play a role in cognitive decline and dementia, but conceptual clarity is lacking and this hinders investigation of associations and mechanisms. The objective is to develop a conceptual framework for social health to advance conceptual clarity in future studies.ProcessWe use the following steps: underpinning for concept advancement, concept advancement by the development of a conceptual model, and exploration of its potential feasibility. An iterative consensus-based process was used within the international multidisciplinary SHARED project.Conceptual frameworkUnderpinning of the concept drew from a synthesis of theoretical, conceptual and epidemiological work, and resulted in a definition of social health as wellbeing that relies on capacities both of the individual and the social environment. Consequently, domains in the conceptual framework are on both the individual (e.g., social participation) and the social environmental levels (e.g., social network). We hypothesize that social health acts as a driver for use of cognitive reserve which can then slow cognitive impairment or maintain cognitive functioning. The feasibility of the conceptual framework is demonstrated in its practical use in identifying and structuring of social health markers within the SHARED project.DiscussionThe conceptual framework provides guidance for future research and facilitates identification of modifiable risk and protective factors, which may in turn shape new avenues for preventive interventions. We highlight the paradigm of social health in dementia as a priority for dementia research.

Dementia is a syndrome where the origins are not fully understood, and we have no cure. New thinking through exploration of paradigms beyond biological approaches has scope to improve knowledge about this complex condition. We aim to explore the role of social health in cognitive decline and the onset of dementia. We performed a scoping and a systematic review of the literature, hypothesizing that social health acts as a driver for stimulating the use of cognitive reserve. The review yielded theoretical pathways and evidence for the association between neurobiological and social health markers. However, lack of conceptual clarity on social health hinders its articulation and associated inclusion of social health markers in epidemiological studies. We therefore apply concept advancement of social health. We developed a conceptual framework, and we present a first testing of our overarching hypothesis. This framework proved to effectively guide the identification of social health markers in our epidemiological data bases. This promotes the identification of modifiable risk factors, which may in turn shape new avenues for preventive interventions.

We examined associations between structural and functional aspects of social health, and subsequent trajectories of cognitive capability (memory, executive functioning, and processing speed).Using data from 16,858 participants (mean age 65.8 years; 56% female) from the National Survey for Health and Development (NSHD), the English Longitudinal Study of Aging (ELSA), the Swedish National Study on Aging and Care in Kungsholmen (SNAC-K), and the Rotterdam Study, we applied multilevel models to examine social health in relation to cognitive capability and the rate of cognitive decline.Those who were married/cohabiting scored 0.07SD (95%CI:0.00,0.14; heterogeneity I2=79%) higher on executive functioning compared to those who lived alone. Associations with memory and processing speed were also heterogeneous (I2>75%); for example, being married was associated with better memory in ELSA (0.05SD 95%CI:0.02,0.08) and SNAC-K (0.13SD 95%CI:0.06,0.20) but not in NSHD nor Rotterdam. Those with larger network sizes (≥6 people) scored higher on executive functioning and processing speed tests, whereas those with frequent social contacts performed better on executive functioning tasks only. Higher participation in social activities and greater perceived positive/less negative social support were associated with higher scores on all cognitive domains. Associations between social health and the rate of cognitive decline varied by social health marker, cognitive domain and study; generally, better social health was associated with a slowing of decline (<0.02 SD/year).Various measures of social health are related to cognitive capability in different ways. These findings may guide future studies to determine if promoting social health at old age may deter cognitive decline.

Background Against the background of urbanization and aging and the aim to design age-friendly cities, it is crucially important to understand whether and why older adults’ health may benefit from being surrounded by older peers mainly, or by residents from all ages. We assessed the association between neighborhood age structure and mental health and the mediating role of social neighborhood perceptions. Methods Survey data were obtained from 1255 older adults aged 65 years and over, participating in the Dutch GLOBE study. The neighborhood age structure, measured in 2011, was defined as the Herfindahl-Hirschman index to assess homogeneity in the age composition (range from 0-100, a higher score indicating more homogeneity) and percentages of different age groups in a neighborhood. Mental health was measured in 2014 by the Mental Health Inventory-5 score, ranging from 0 to 100, where a higher score indicates better mental health. Perceptions of neighborhood social cohesion, feeling at home in a neighborhood, and social participation was assessed in 2011. Linear regression models were used to assess the association of neighborhood age composition with mental health. Causal mediation analysis was used to assess the potential mediating role of social neighborhood perceptions. Results A more homogeneous neighborhood age structure was associated with better mental health status. Feeling at home in a neighborhood partly mediated the association, whereas social cohesion and social participation did not mediate the association. While a higher percentage of children in the neighborhood was associated with better mental health, a higher percentage of elderly in the neighborhood was associated with lower mental health status. Conclusions The neighborhood age composition is a promising, but currently insufficiently understood, entry point for policies addressing the challenge of growing urban and aging European cities. Key messages The neighborhood age composition is a promising, but currently insufficiently understood, entry point for policies addressing the challenge of growing urban and aging European cities. Feeling at home in a neighborhood partly mediated the association between neighborhood age structure and mental health; social cohesion and social participation did not mediate the association.