Disentangling the relationship between falls, fear of falling, physical function and walking by applying a socioecological framework to the International Mobility in Aging Study

Introduction:The relationships between falls, fear of falling, poor mobility, and PA avoidance occur in a cyclic, multi-directional fashion. Aim: This study investigates the concomitant associations of fall history, fear of falling, and physical performance (SPPB) on physical activity using a cross-national sample of community-dwelling older adults from middle and high-income countries.Methods:Linear mixed-effects models looking at the influence of individual and environmental factors were used and participants were nested within each study site.Results:Estimated walking minutes was 52% lower for those with low SPPB compared to high SPPB, 20% lower for those with medium level fear of falling compared to low levels, and 50% lower for those with high level fear of falling compared to low levels.Conclusion:An individual’s fear of falling and physical performance may be important to consider when making PA recommendations to older adults regardless of sex, age, and environment

Childhood adversity and leisure time physical and sports activity in older adults: A cross-sectional analysis from the International Mobility in Aging Study

Aim: The purpose is to examine the relationship between childhood adversity and leisure time physical activity (LTPA) among community-dwelling older adults from high and middle-income sites. Methods: Cross-sectional analysis of 2012 data from older adult ages 64-75 years old from King-ston, Canada; St. Hyacinthe, Canada; Tirana, Albania; Manizales, Colombia; and Natal, Brazil. Principal exposure variables were childhood social and economic adversity. Covariates included participant age, sex, income, and educational attainment. Outcome variables were LTPA and lei-sure time sports activity (LTSA). Results: High-income sites had higher LTPA prevalence than middle-income sites. Females were less likely to engage in LTPA compared to males in Tirana (OR:0.53, 95%CI:0.30-0.94), but were more likely to engage in LTPA in Manizales (OR:2.54, 95%CI:1.54-4.18). Low education was less likely than high education to engage in LTPA in Kingston (OR:0.38, 95%CI:0.19-0.73) and Natal (OR: 0.52, 95%CI:0.28-0.97). Low income was less likely than high income to engage in LTPA in St. Hyacinthe (OR: 0.42, 95%CI:0.20-0.89) and Manizales (OR:0.33, 95%CI:0.16-0.55). In Tirana, low income was more likely than high income to engage in LTPA (OR:5.27, 95%CI:2.06-13.51). Conclusions: Childhood economic and social adversity were not significantly associated with LTPA. Sex, income, and education were associated with older adult PA engagement, however the direction of the association varied by site location. This suggests that the paradigms surrounding PA behavior may vary from city to city. Understanding the site-specific risk factors to PA engage-ment may better inform clinical recommendations and public health approaches to increase PA engagement among older adults across the globe

Trajectories of frailty with aging:Coordinated analysis of five longitudinal studies

BACKGROUND AND OBJECTIVES: There is an urgent need to better understand frailty and its predisposing factors. Although numerous cross-sectional studies have identified various risk and protective factors of frailty, there is a limited understanding of longitudinal frailty progression. Furthermore, discrepancies in the methodologies of these studies hamper comparability of results. Here, we use a coordinated analytical approach in 5 independent cohorts to evaluate longitudinal trajectories of frailty and the effect of 3 previously identified critical risk factors: sex, age, and education. RESEARCH DESIGN AND METHODS: We derived a frailty index (FI) for 5 cohorts based on the accumulation of deficits approach. Four linear and quadratic growth curve models were fit in each cohort independently. Models were adjusted for sex/gender, age, years of education, and a sex/gender-by-age interaction term. RESULTS: Models describing linear progression of frailty best fit the data. Annual increases in FI ranged from 0.002 in the Invecchiare in Chianti cohort to 0.009 in the Longitudinal Aging Study Amsterdam (LASA). Women had consistently higher levels of frailty than men in all cohorts, ranging from an increase in the mean FI in women from 0.014 in the Health and Retirement Study cohort to 0.046 in the LASA cohort. However, the associations between sex/gender and rate of frailty progression were mixed. There was significant heterogeneity in within-person trajectories of frailty about the mean curves. DISCUSSION AND IMPLICATIONS: Our findings of linear longitudinal increases in frailty highlight important avenues for future research. Specifically, we encourage further research to identify potential effect modifiers or groups that would benefit from targeted or personalized interventions

Contributions of the MyD88-Dependent Receptors IL-18R, IL-1R, and TLR9 to Host Defenses following Pulmonary Challenge with Cryptococcus neoformans

Signaling via the adapter protein, MyD88, is important in the host defense against Cryptococcus neoformans infection. While certain Toll-like receptors (TLRs) can enhance the clearance of Cryptococcus, the contributions of MyD88-dependent, TLR-independent pathways have not been fully investigated. We examined the roles of IL-1R and IL-18R in vivo by challenging C57BL/6 mice with a lethal strain of Cryptococcus. We found that the absence of IL-18R, but not IL-1R, causes a shift in the survival curve following pulmonary delivery of a virulent strain of C. neoformans (H99). Specifically, IL-18R-deficient mice have significantly shorter median survival times compared to wild-type mice following infection. Cytokine analysis of lung homogenates revealed that deficiency of IL-IR, IL-18R, or MyD88 is associated with diminished lung levels of IL-1β. In order to compare these findings with those related to TLR-deficiency, we studied the effects of TLR9-deficiency and found that deficiency of TLR9 also affects the survival curve of mice following challenge with C. neoformans. Yet the lungs from infected TLR9-deficient mice have robust levels of IL-1β. In summary, we found that multiple signaling components can contribute the MyD88-dependent host responses to cryptococcal infection in vivo and each drives distinct pulmonary responses

Comparison of self-rated and objective successful ageing in an international cohort

ABSTRACTUnderstanding predictors of successful ageing is essential to policy development promoting quality-of-life of an ageing population. Initial models precluded successful ageing in the presence of chronic disease/functional disability; however, this is discrepant with self-reported successful ageing. Indicators of social, psychological and physical health in 1,735 people aged 65–74, living in Canada, Columbia, Brazil or Albania, were analysed in the International Mobility in Ageing Study. Multiple logistic regression analysis was performed to estimate the change in self-rated successful ageing in relation to physical health, depression, social connectedness, resilience and site, while controlling for age, gender and income sufficiency. Sixty-five per cent of participants self-rated as ageing successfully; however, this was significantly different across sites (p &lt; 0.0005, range 17–85%) and gender (p = 0.019). Using objective measures, 6 per cent were classified as ‘successful’, with significant variability amongst sites (p &lt; 0.0005, range 0–12%). Subjective successful ageing was associated with fewer (not absence of) chronic diseases, absence of depression and less dysfunction in activities of daily living, but not with objective measures of physical dysfunction. Social connectedness and resilience also aligned with self-rated successful ageing. Traditional definitions of objective successful ageing are likely too restrictive, and thus, do not approximate self-rated successful ageing. International differences suggest that site could be a surrogate for variables other than physical/mental health and social engagement.</jats:p