Relation between frailty and hypertension is partially mediated by physical activity among males and females in the Canadian Longitudinal Study on Aging.

Frailty reflects the heterogeneity in aging and may lead to the development of hypertension and heart disease, but the frailty-cardiovascular relationship and whether physical activity modifies this relationship in males and females are unclear. We tested whether higher frailty was positively associated with hypertension and heart disease in males and females and whether habitual movement mediated this relationship. The relationship between baseline frailty with follow-up hypertension and heart disease was investigated using the Canadian Longitudinal Study on Aging at 3-year follow-up data (males: n = 13,095; females: n = 13,601). Frailty at baseline was determined via a 73-item deficit-based index, activity at follow-up was determined via the Physical Activity Scale for the Elderly, and cardiovascular function was self-reported. Higher baseline frailty level was associated with a greater likelihood of hypertension and heart disease at follow-up, with covariate-adjusted odds ratios of 1.08-1.09 (all, P < 0.001) for a 0.01 increase in frailty index score. Among males and females, sitting time and strenuous physical activity were independently associated with hypertension, with these activity behaviors being partial mediators (except male-sitting time) for the frailty-hypertension relationship (explained 5-10% of relationship). The strength of this relationship was stronger among females. Only light-moderate activity partially mediated the relationship (∼6%) between frailty and heart disease in females, but no activity measure was a mediator for males. Higher frailty levels were associated with a greater incidence of hypertension and heart disease, and strategies that target increases in physical activity and reducing sitting may partially uncouple this relationship with hypertension, particularly among females.NEW & NOTEWORTHY Longitudinally, our study demonstrates that higher baseline frailty levels are associated with an increased risk of hypertension and heart disease in a large sample of Canadian males and females. Movement partially mediated this relationship, particularly among females.

Genome-Wide Meta-analysis Identifies Risk Loci and Improves Disease Prediction of Age-Related Macular Degeneration.

PURPOSE: To identify age-related macular degeneration (AMD) risk loci and to establish a polygenic prediction model. DESIGN: Genome-wide association study (GWAS) and polygenic risk score (PRS) construction. PARTICIPANTS: We included 64 885 European patients with AMD and 568 740 control participants (with overlapped samples) in the UK Biobank, Genetic Epidemiology Research on Aging (GERA), International AMD Consortium, FinnGen, and published early AMD GWASs in meta-analyses, as well as 733 European patients with AMD and 20 487 control participants from the Canadian Longitudinal Study on Aging (CLSA) and non-Europeans from the UK Biobank and GERA for polygenic risk score validation. METHODS: A multitrait meta-analysis of GWASs comprised 64 885 patients with AMD and 568 740 control participants; the multitrait approach accounted for sample overlap. We constructed a PRS for AMD based on both previously reported as well as unreported AMD loci. We applied the PRS to nonoverlapping data from the CLSA. MAIN OUTCOME MEASURES: We identified several single nucleotide polymorphisms associated with AMD and established a PRS for AMD risk prediction. RESULTS: We identified 63 AMD risk loci alongside the well-established AMD loci CFH and ARMS2, including 9 loci that were not reported in previous GWASs, some of which previously were linked to other eye diseases such as glaucoma (e.g., HIC1). We applied our PRS to nonoverlapping data from the CLSA. A new PRS was constructed using the PRS method, PRS-CS, and significantly improved the prediction accuracy of AMD risk compared with PRSs from previously published datasets. We further showed that even people who carry all the well-known AMD risk alleles at CFH and ARMS2 vary considerably in their AMD risk (ranging from close to 0 in individuals with low PRS to > 50% in individuals with high PRS). Although our PRS was derived in individuals of European ancestry, the PRS shows potential for predicting risk in people of East Asian, South Asian, and Latino ancestry. CONCLUSIONS: Our findings improve the knowledge of the genetic architecture of AMD and help achieve better accuracy in AMD prediction. FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Geographic variation in bone mineral density and prevalent fractures in the Canadian longitudinal study on aging.

Awareness of the prevalence of osteoporosis and fractures across jurisdictions can guide the development of local preventive programs and healthcare policies. We observed geographical variations in total hip bone mineral density and in the prevalence of major osteoporotic fractures across Canadian provinces, which persisted after adjusting for important covariates. PURPOSE: We aimed to describe sex-specific total hip bone mineral density (aBMD) and prevalent major osteoporotic fractures (MOF) variation between Canadian provinces. METHODS: We used baseline data from 21,227 Canadians (10,716 women, 10,511 men) aged 50-85 years in the Canadian Longitudinal Study on Aging (CLSA; baseline: 2012-2015). Linear and logistic regression models were used to examine associations between province of residence and total hip aBMD and self-reported MOF, stratified by sex. CLSA sampling weights were used to generate the prevalence and regression estimates. RESULTS: The mean (SD) age of participants was 63.9 (9.1) years. The mean body mass index (kg/m2) was lowest in British Columbia (27.4 [5.0]) and highest in Newfoundland and Labrador (28.8 [5.3]). Women and men from British Columbia had the lowest mean total hip aBMD and the lowest prevalence of MOF. Alberta had the highest proportion of participants reporting recent falls (12.0%), and Manitoba (8.4%) the fewest (p-value=0.002). Linear regression analyses demonstrated significant differences in total hip aBMD: women and men from British Columbia and Alberta, and women from Manitoba and Nova Scotia had lower adjusted total hip aBMD than Ontario (p-values<0.02). Adjusted odds ratios (95% confidence intervals, CI) for prevalent MOF were significantly lower in women from British Columbia (0.47 [95% CI: 0.32; 0.69]) and Quebec (0.68 [95% CI: 0.48; 0.97]) and in men from British Columbia (0.40 [95% CI:0.22; 0.71]) compared to Ontario (p-values<0.03). Results were similar when adjusting for physical performance measures and when restricting the analyses to participants who reported White race/ethnicity. CONCLUSION: Geographical variations in total hip aBMD and in the prevalence of MOF between provinces persisted after adjusting for important covariates which suggests an association with unmeasured individual and environmental factors.

The Effects of Cognitive Ability, Mental Health, and Self-Quarantining on Functional Ability of Older Adults During the COVID-19 Pandemic: Results From the Canadian Longitudinal Study on Aging.

OBJECTIVES: Determine whether levels of anxiety and depression, cognitive ability, and self-quarantining during and prior to the pandemic predict decreases in perceived functional ability. DESIGN AND SETTING: Longitudinal data collected from the Canadian Longitudinal Study on Aging (CLSA) COVID-19 Questionnaire Study (2020) and core CLSA study (Follow-Up 1; 2014-2018). PARTICIPANTS: 17 541 CLSA participants. MEASUREMENTS: Self-quarantining behaviours from questionnaires administered at Baseline (April 2020), Monthly, and Exit (December 2020) time points of the CLSA COVID-19 Questionnaire Study, levels of anxiety and depression at Baseline, perceived change in functional ability at Exit, and performance on neuropsychological tests (Rey Auditory Verbal Learning Task, Mental Alternation Task, Animal Fluency Test) and functional ability (Older Americans Resources and Services [OARS] Multidimensional Assessment Questionnaire) from the core CLSA study. RESULTS: Greater cognitive ability pre-pandemic (B = -.003, P < .01), higher levels of anxiety (B = -.024, P < .01) and depressive symptoms (B = -.110, P < .01) at Baseline, and higher frequency of engaging in self-quarantining throughout the COVID-19 survey period (B = -.098, P < .01) were associated with perceived loss in functional ability at Exit. Self-quarantining behaviour was associated with perceived loss in functional ability only at average and high levels of depressive symptoms (B = -.013, P < .01). CONCLUSIONS: Older adults with higher cognitive and lower functional ability prior to the pandemic were at greater risk of decreased perceived functional ability during the first year of the pandemic, as were those who experienced greater levels of anxiety and depressive symptoms during the pandemic. Strategies/interventions to preserve functional ability in older adults with cognitive independence prior to future pandemics are warranted.

Mediation of Post-Stroke Function by Cognition in the Canadian Longitudinal Study on Aging.

INTRODUCTION: Cognitive and functional impairment after stroke are common, but the relation between cognitive and functional decline after stroke is not well studied. METHODS: We used the comprehensive cohort in the Canadian Longitudinal Study on Aging to identify those with prior stroke, and we calculated reliable cognitive change scores from baseline to follow-up for the memory and executive domains. Functional decline was defined as an increase in the number of dependent daily activities. Using formal mediation analysis, we tested the presence and degree of mediation of the association between stroke and functional decline by cognitive decline. RESULTS: There were 22,648 individuals with memory change scores (325 with stroke) and 17,613 individuals with executive change scores (241 with stroke). History of stroke was significantly associated with memory decline (-0.26 standard deviations, 95% CI -0.33 to -0.19), executive decline (-0.22, 95% CI -0.36 to -0.09), and new functional impairment (adjusted odds ratio 2.31, 95% CI 1.80-2.97) over a median of 3-year follow-up. Cognitive decline was a significant mediator of functional decline. Memory decline mediated only 5% of the relationship, whereas executive and overall cognitive decline mediated 13% and 22%, respectively. CONCLUSION: Cognitive decline is a mediator of the association between prior stroke and functional decline; consequently, strategies to delay, attenuate, or prevent cognitive decline after stroke may be important to preserving long-term functional status.

Variation in bone mineral density and fractures over 20 years among Canadians: a comparison of the Canadian Multicenter Osteoporosis Study and the Canadian Longitudinal Study on Aging.

International variations in osteoporosis and fracture rates have been reported, with temporal trends differing between populations. We observed higher BMD and lower fracture prevalence in a recently recruited cohort compared to that of a cohort recruited 20 years ago, even after adjusting for multiple covariates. PURPOSE: We explored sex-specific differences in femoral neck bone mineral density (FN-BMD) and in prevalent major osteoporotic fractures (MOF) using two Canadian cohorts recruited 20 years apart. METHODS: We included men and women aged 50-85 years from the Canadian Multicentre Osteoporosis Study (CaMos, N = 6,479; 1995-1997) and the Canadian Longitudinal Study on Aging (CLSA, N = 19,534; 2012-2015). We created regression models to compare FN-BMD and fracture risk between cohorts, adjusting for important covariates. Among participants with prevalent MOF, we compared anti-osteoporosis medication use. RESULTS: Mean (SD) age in CaMos (65.4 years [8.6]) was higher than in CLSA (63.8 years [9.1]). CaMos participants had lower mean body mass index and higher prevalence of smoking (p < 0.001). Adjusted linear regression models (estimates [95%CI]) demonstrated lower FN-BMD in CaMos women (- 0.017 g/cm2 [- 0.021; - 0.014]) and men (- 0.006 g/cm2 [- 0.011; 0.000]), while adjusted odds ratios (95%CI) for prevalent MOF were higher in CaMos women (1.99 [1.71; 2.30]) and men (2.33 [1.82; 3.00]) compared to CLSA. In women with prevalent MOF, menopausal hormone therapy use was similar in both cohorts (43.3% vs 37.9%, p = 0.076), but supplements (32.0% vs 48.3%, p < 0.001) and bisphosphonate use (5.8% vs 17.3%, p < 0.001) were lower in CaMos. The proportion of men with MOF who received bisphosphonates was below 10% in both cohorts. CONCLUSION: Higher BMD and lower fracture prevalence were noted in the more recently recruited CLSA cohort compared to CaMos, even after adjusting for multiple covariates. We noted an increase in bisphosphonate use in the recent cohort, but it remained very low in men.

Biopsychosocial Correlates of Subjective Cognitive Decline and Related Worry in the Canadian Longitudinal Study on Aging.

INTRODUCTION: Subjective cognitive decline (SCD), a self-reported decline in cognition in otherwise cognitively healthy people, has been acknowledged as a risk factor for Alzheimer's disease. Using data from the Canadian Longitudinal Study on Aging (CLSA), a large national study with participants' ages of 45-85 years at baseline, we sought to identify correlates of SCD and SCD-related worry. METHODS: In our primary analysis using a Poisson regression model, associations between biopsychosocial variables and SCD were identified (analytic sample: n = 21,920). In a second analysis using an ordinal regression model, associations between biopsychosocial variables and SCD-related worry were identified (analytic sample: n = 12,694). RESULTS: Multiple risk and protective factors of cognitive decline were not associated with SCD within our sample (i.e., physical activity, hypertension, vision problems), as well as minority stress variables such as sexual orientation and race. Rather, psychosocial variables (i.e., depression, perceived social status, and personality traits) showed a more consistent association with SCD within the sample. Greater SCD-related worry, which is believed to increase the risk of future dementia, was associated with specific personality traits, depression, age, gender, and sexuality. CONCLUSION: The results from this study confirm the association between multiple health variables and SCD but also emphasize the importance of considering psychological and social factors when conceptualizing SCD and its risk factors.

Examination of the Healthy Caregiver Effect among Older Adults: Findings from the Canadian Longitudinal Study on Aging.

INTRODUCTION: The Healthy Caregiver Hypothesis (HCH) suggests that caregiving is associated with beneficial health impacts for family caregivers. However, mixed results have been reported, particularly when different levels of caregiving intensity were examined. This study analyzes the relationship between caregiving intensity and three health indicators (functional health, chronic illness, and self-rated general health) among Canadian older adults over 3 years. METHODS: We drew upon a subsample of 11,344 participants aged 65 years and older from the Baseline and Follow-up 1 data of the Canadian Longitudinal Study on Aging and used linear mixed models to test the hypothesis based on different levels of caregiving intensity. RESULTS: Older adults who provided low-intensity care recently or continuously reported better functional health and self-rated health than noncaregivers. In contrast, older adults with low-intensity caregiving responsibility reported more chronic conditions over time compared to noncaregivers, but this association was not found for high-intensity caregivers. DISCUSSION/CONCLUSION: This study elucidates the HCH by incorporating caregiving intensity to understand patterns of better functional health and perceived health but more chronic conditions. The findings yielded from different health indicators suggest the impact of caregiving on health may be domain specific.

Factors Associated With Willingness to Receive a COVID-19 Vaccine Among 23,819 Adults Aged 50 Years or Older: An Analysis of the Canadian Longitudinal Study on Aging.

Identifying persons who are least willing to receive a coronavirus disease 2019 (COVID-19) vaccine is critical for increasing uptake via targeted outreach. We conducted a survey of 23,819 Canadian Longitudinal Study on Aging participants from September 29 to December 29, 2020, to assess factors associated with COVID-19 vaccination willingness and reasons for willingness or lack thereof. Among adults aged 50-96 years, 84.1% (95% confidence interval (CI): 83.7, 84.6) were very or somewhat willing to receive a COVID-19 vaccine; 15.9% (95% CI: 15.4, 16.3) were uncertain or very or somewhat unwilling. Based on logistic regression, those who were younger, female, had lower education and income, were non-White, and lived in a rural area were less willing to receive a COVID-19 vaccine. After controlling for these factors, recent receipt of influenza vaccine (adjusted odds ratio = 14.3, 95% CI: 12.5, 16.2) or planning to receive influenza vaccine (adjusted odds ratio = 10.5, 95% CI: 9.5, 11.6), as compared with no receipt or planning, was most strongly associated with COVID-19 vaccination willingness. Willingness was also associated with believing one had never been infected with severe acute respiratory syndrome coronavirus 2 (SARS-Cov-2) and experiencing negative pandemic consequences. Safety concerns were most common among those unwilling. Our comprehensive assessment of COVID-19 vaccination willingness among older adults in Canada, a prioritized group for vaccination due to their risk of severe COVID-19 outcomes, provides a road map for conducting outreach to increase uptake, which is urgently needed.

Race/ethnic differences in the prevalence of osteoporosis, falls and fractures: a cross-sectional analysis of the Canadian Longitudinal Study on Aging.

Most of the published epidemiology on osteoporosis is derived from White populations; still many countries have increasing ethno-culturally diverse populations, leading to gaps in the development of population-specific effective fracture prevention strategies. We describe differences in prevalent fracture and bone mineral density patterns in Canadians of different racial/ethnic backgrounds. INTRODUCTION: We described prevalent fracture and bone mineral density (BMD) patterns in Canadians by their racial/ethnic backgrounds. METHODS: For this cross-sectional analysis, we used the Canadian Longitudinal Study on Aging baseline data (2011-2015) of 22,091 randomly selected participants of Black, East Asian, South or Southeast Asian (SSEA) and White race/ethnic backgrounds, aged 45-85 years with available information on the presence or absence of self-reported prevalent low trauma fractures and femoral neck BMD (FNBMD) measurement. Logistic and linear regression models examined associations of race/ethnic background with fracture and FNBMD, respectively. Covariates included sex, age, height, body mass index (BMI), grip strength and physical performance score. RESULTS: We identified 11,166 women and 10,925 men. Self-reported race/ethnic backgrounds were: 139 Black, 205 East Asian, 269 SSEA and 21,478 White. White participants were older (mean 62.5 years) than the other groups (60.5 years) and had a higher BMI (28.0 kg/m2) than both Asian groups, but lower than the Black group. The population-weighted prevalence of falls was 10.0%, and that of low trauma fracture was 12.0% ranging from 3.3% (Black) to 12.3% (White), with Black and SSEA Canadians having lower adjusted odds ratios (aOR) of low trauma fractures than White Canadians (Black, aOR = 0.3 [95% confidence interval: 0.1-0.7]; SSEA, aOR = 0.5 [0.3-0.8]). The mean (SD) FNBMD varied between groups: Black, 0.907 g/cm2 (0.154); East Asian, 0.748 g/cm2 (0.119); SSEA, 0.769 g/cm2 (0.134); and White, 0.773 g/cm2 (0.128). Adjusted linear regressions suggested that Black and both Asian groups had higher FNBMD compared to White. CONCLUSION: Our results support the importance of characterizing bone health predictors in Canadians of different race/ethnic backgrounds to tailor the development of population-specific fracture prevention strategies.

Frailty indices based on self-report, blood-based biomarkers and examination-based data in the Canadian Longitudinal Study on Aging.

BACKGROUND: Frailty can be operationalised using the deficit accumulation approach, which considers health deficits across multiple domains. We aimed to develop, validate and compare three different frailty indices (FI) constructed from self-reported health measures (FI-Self Report), blood-based biomarkers (FI-Blood) and examination-based assessments (FI-Examination). METHODS: Up to 30,027 participants aged 45-85 years from the baseline (2011-2015) comprehensive cohort of the Canadian Longitudinal Study on Aging were included in the analyses. Following standard criteria, three FIs were created: a 48-item FI-Self Report, a 23-item FI-Blood and a 47-item FI-Examination. In addition a 118-item FI-Combined was constructed. Mortality status was ascertained in July 2019. RESULTS: FI-Blood and FI-Examination demonstrated broader distributions than FI-Self Report. FI-Self Report and FI-Blood scores were higher in females, whereas FI-Examination scores were higher in males. All FI scores increased nonlinearly with age and were highest at lower education levels. In sex and age-adjusted models, a 0.01 increase in FI score was associated with a 1.08 [95% confidence interval (CI): 1.07,1.10], 1.05 (1.04,1.06), 1.07 (1.05,1.08) and a 1.13 (1.11,1.16) increased odds of mortality for FI-Self Report, FI-Blood, FI-Examination and FI-Combined, respectively. Inclusion of the three distinct FI types in a single model yielded the best prognostic accuracy and model fit, even compared to the FI-Combined, with all FIs remaining independently associated with mortality. CONCLUSION: Characteristics of all FIs were largely consistent with previously established FIs. To adequately capture frailty levels and to improve our understanding of the heterogeneity of ageing, FIs should consider multiple types of deficits including self-reported, blood and examination-based measures.

Examining the prevalence and correlates of multimorbidity among community-dwelling older adults: cross-sectional evidence from the Canadian Longitudinal Study on Aging (CLSA) first-follow-up data.

INTRODUCTION: multimorbidity has become an increasingly important issue for many populations around the world, including Canada. The objectives of this study were to estimate the prevalence of multimorbidity at first follow-up and to identify factors associated with multimorbidity using data from the Canadian Longitudinal Study on Aging (CLSA). METHODS: this study included 27,701 community-dwelling participants in the first follow-up of the CLSA. Multimorbidity was operationalised using two definitions (Public Health and Primary Care), as well as the cut-points of two or more chronic conditions (MM2+) and three or more chronic conditions (MM3+). The prevalence of multimorbidity was calculated at first follow-up and multivariable regression models were used to identify correlates of multimorbidity occurrence. RESULTS: the prevalence of multimorbidity at first follow-up was 32.3% among males and 39.3% among females when using the MM2+ Public Health definition, whereas the prevalence was 67.2% among males and 75.8% among females when using the MM2+ Primary Care definition. Older age, lower alcohol consumption, lower physical activity levels, dissatisfaction with sleep quality, dissatisfaction with life and experiencing social limitations due to health conditions were significantly associated with increased odds of multimorbidity for both males and females, regardless of the definition of multimorbidity used. CONCLUSION: various sociodemographic, behavioural and psychosocial factors are associated with multimorbidity. Future research should continue to examine how the prevalence of multimorbidity changes with time and how these changes may be related to specific risk factors. This future research should be supplemented with studies examining the longitudinal impacts of multimorbidity over time.

Frailty and the impacts of the COVID-19 pandemic on community-living middle-aged and older adults: an analysis of data from the Canadian Longitudinal Study on Aging (CLSA).

BACKGROUND: frailty imparts a higher risk for hospitalisation, mortality and morbidity due to COVID-19 infection, but the broader impacts of the pandemic and associated public health measures on community-living people with frailty are less known. METHODS: we used cross-sectional data from 23,974 Canadian Longitudinal Study on Aging participants who completed a COVID-19 interview (Sept-Dec 2020). Participants were included regardless of whether they had COVID-19 or not. They were asked about health, resource, relationship and health care access impacts experienced during the pandemic. Unadjusted and adjusted prevalence of impacts was estimated by frailty index quartile. We further examined if the relationship with frailty was modified by sex, age or household income. RESULTS: community-living adults (50-90 years) with greater pre-pandemic frailty reported more negative impacts during the first year of the pandemic. The frailty gradient was not explained by socio-demographic or health behaviour factors. The largest absolute difference in adjusted prevalence between the most and least frail quartiles was 15.1% (challenges accessing healthcare), 13.3% (being ill) and 7.4% (increased verbal/physical conflict). The association between frailty and healthcare access differed by age where the youngest age group tended to experience the most challenges, especially for those categorised as most frail. CONCLUSION: although frailty has been endorsed as a tool to inform estimates of COVID-19 risk, our data suggest it may have a broader role in primary care and public health by identifying people who may benefit from interventions to reduce health and social impacts of COVID-19 and future pandemics.

Associations of Adverse Childhood Experiences with Frailty in Older Adults: A Cross-Sectional Analysis of Data from the Canadian Longitudinal Study on Aging.

INTRODUCTION: Frailty in older adults, characterized by a decline in multiple physiological systems and increasing vulnerability to loss of independence, disability, and death, is a public health priority in developed countries. Etiology of frailty extends across the lifespan and may begin in early life, but empirical evidence for this association is scarce. In this study, we examined whether adverse childhood experiences (ACEs) are associated with frailty in later life. METHODS: We conducted a cross-sectional analysis of data for a population-based sample of 27,748 adults aged 45-85 years from the Canadian Longitudinal Study on Aging. The frailty index (FI) was computed with 76 health-related characteristics of physical and cognitive performance, self-rated health, chronic conditions, visual and hearing ability, activities of daily living, and well-being. Self-reported exposure to ACEs included physical, emotional, and sexual abuse, neglect, and witnessing intimate partner violence prior age of 16 and parental death, divorce, and living with a family member with mental illness prior age of 18. Generalized linear regression models with gamma error distribution and identity link function, adjusted for age and sex, were used to examine associations of each ACE type and the number of ACE types (0, 1, 2, or 3+) reported by an individual with FI. All models were adjusted for income, education, smoking, and alcohol consumption in sensitivity analysis. RESULTS: Individuals exposed to ACEs had elevated levels of FI (mean = 0.13, SD = 0.09) than those unexposed, with the largest difference observed for neglect (B [95% CI]: 0.05 [0.04, 0.06]) and the smallest for parental death and divorce (0.015 [0.01,0.02]). The ACE count was associated with frailty in a graded manner, with the FI difference reaching 0.04 [0.037, 0.044] for participants exposed to 3+ ACE types. The association between ACEs and frailty tended to be stronger for women than men and for men aged 45-64 years than older men. CONCLUSIONS: Our study supports previous studies showing that exposure to ACEs is associated with frailty in adults. Our findings suggest that screening for ACEs involving childhood maltreatment may be useful for identifying individuals at risk of frailty and prevention of ACEs may have long-term benefits for healthy aging.

Advanced biological age is associated with improved antibody responses in older high-dose influenza vaccine recipients over four consecutive seasons.

BACKGROUND: Biological aging represents a loss of integrity and functionality of physiological systems over time. While associated with an enhanced risk of adverse outcomes such as hospitalization, disability and death following infection, its role in perceived age-related declines in vaccine responses has yet to be fully elucidated. Using data and biosamples from a 4-year clinical trial comparing immune responses of standard- and high-dose influenza vaccination, we quantified biological age (BA) prior to vaccination in adults over 65 years old (n = 292) using a panel of ten serological biomarkers (albumin, alanine aminotransferase, creatinine, ferritin, free thyroxine, cholesterol, high-density lipoprotein, triglycerides, tumour necrosis factor, interleukin-6) as implemented in the BioAge R package. Hemagglutination inhibition antibody titres against influenza A/H1N1, A/H3N2 and B were quantified prior to vaccination and 4-, 10- and 20- weeks post-vaccination. RESULTS: Counter to our hypothesis, advanced BA was associated with improved post-vaccination antibody titres against the different viral types and subtypes. However, this was dependent on both vaccine dose and CMV serostatus, as associations were only apparent for high-dose recipients (d = 0.16-0.26), and were largely diminished for CMV positive high-dose recipients. CONCLUSIONS: These findings emphasize two important points: first, the loss of physiological integrity related to biological aging may not be a ubiquitous driver of immune decline in older adults; and second, latent factors such as CMV infection (prevalent in up to 90% of older adults worldwide) may contribute to the heterogeneity in vaccine responses of older adults more than previously thought.

Clustering of obesity-related characteristics: A latent class analysis from the Canadian Longitudinal Study on Aging.

Measures of obesity, including body mass index (BMI) and waist circumference (WC), do not fully capture the complexity of obesity-related health risks. This study identified distinct classes of obesity-related characteristics and evaluated their associations with BMI, WC, and percent body fat (%BF) using cross-sectional data from 30,096 participants aged 45-85 in the Canadian Longitudinal Study on Aging (2011-2015). Sixteen obesity-related variables, including behavioural, metabolic, physical health, and mental health/social factors, were included in a latent class analysis to identify distinct classes of participants. Adjusted odds ratios (OR) were estimated from logistic regression for associations between each class and obesity defined by BMI, WC and %BF. Six latent classes were identified: "low-risk" (39.8%), "cardiovascular risk" (19.4%), "metabolic risk" (16.9%), "sleep and mental health risk" (12.1%), "multiple and complex risk" (6.7%), and "cardiometabolic risk" (5.1%). Compared to "low-risk", all classes had increased odds of BMI-, WC- and %BF-defined obesity. For example, the "complex and multiple risk" class was associated with obesity by BMI (OR: 10.70, 95% confidence interval (CI): 9.51, 12.04), WC (OR: 9.21, 95% CI: 8,15, 10,41) and %BF (OR: 7.54, 95% CI: 6.21, 9.16). Distinct classes of obesity-related characteristics were identified and were strongly associated with obesity defined by multiple measures.

Adiposity and the role of diverse social supports: an observational, gender-sensitive study using the baseline Canadian Longitudinal Study on Aging.

OBJECTIVE: To quantify associations between four types of social support and measured adiposity among women and men. DESIGN: The cross-sectional sample from the Canadian Longitudinal Study on Aging (CLSA, 2012-2015). Height, weight and waist circumference (WC) were clinically measured, and perceived availability of informational, tangible, emotional and belonging social supports was self-reported. SETTING: Canada. PARTICIPANTS: 28 779 adults aged 45-85 years from the CLSA. RESULTS: All social support types were associated with WC and BMI among women but not among men. Women reporting the lowest informational support had significantly higher mean BMI (28·84 kg/m2 (95 % CI 28·63, 29·05)) and WC (90·81 cm (95 % CI 90·31, 91·30)) compared with women reporting maximum support (respectively, 28·09 kg/m2 (95 % CI 27·88, 28·30) and 88·92 cm (95 % CI 88·43, 89·4)). Women's abdominal obesity was associated with low levels of informational, emotional and belonging support, and women's general obesity with informational and emotional support. Notably, informational and emotional support were associated with both obesity outcomes independent of other supports among women. Only a low level of informational support was significantly independently associated with higher odds of obesity among men. CONCLUSIONS: Our study provides novel insights into gender-specific associations between different types of social support and adiposity. Prospective studies are needed to further investigate potential causality of these associations between the specific social supports and future weight status, especially among women.

Modifiable factors related to life-space mobility in community-dwelling older adults: results from the Canadian Longitudinal Study on Aging.

BACKGROUND: The most common methods for measuring mobility in older adulthood include performance-based tests, such as the Timed-Up-and-Go and gait speed. While these measures have strong predictive validity for adverse outcomes, they are limited to assessing what older adults do in standardized settings, rather than what they do in their daily life. Life-space mobility, which is the ability to move within environments that expand from one's home to the greater community, has been proposed as a more comprehensive measure of mobility. The aim of this study was to determine the association between modifiable factors and life-space mobility in older adults enrolled in the Canadian Longitudinal Study on Aging (CLSA). METHODS: Life-space mobility was measured using the Life Space Index (LSI). Explanatory factors included physical, psychosocial and cognitive determinants, as well as pain, fatigue, driving status, nutrition, body mass index, smoking status, and vision. To estimate the association between the LSI and explanatory variables, univariate and multivariable ordinary least squares regression analyses were performed. RESULTS: All adults 65 years and older (n = 12,646) were included in the analysis. Fifty percent were women and the mean age was 73.0 (SD5.7). The mean LSI score was 80.5, indicating that, on average, the sample was able to move outside of their neighborhood independently. All explanatory variables were significantly associated with the LSI except for balance and memory. The top 3 variables that explained the most variation in the LSI were driving, social support and walking speed. CONCLUSION: To our knowledge, this was the first study to examine the association between life-space mobility and a comprehensive set of modifiable factors that were selected based on a theoretical framework and existing research evidence. This study had two important messages. First, driving, social support and walking speed emerged as the most significant correlates of life-space mobility in older adults. Second, life-space mobility is multifactorial and interventions that are pragmatic in their design and testing are needed that consider the complexity involved. A multi-disciplinary approach to examining life-space mobility in older adults is needed to optimize opportunities for healthy aging and develop strategies that support mobility in older adulthood.

Social support, social participation, & depression among caregivers and non-caregivers in Canada: a population health perspective.

Objectives: The study used data from the Canadian Longitudinal Study on Aging to investigate the relationships among social support (measured as affectionate support, emotional/informational support, positive social interaction, tangible support), social participation and depression in caregivers and non-caregivers.Method: Hierarchical multiple regression was used to investigate relationships among social support, social participation, and depression. Analyses of variance were used to examine differences in the means of social support, social participation, and depression between the two participant groups.Results: Higher levels of affectionate support, positive social interaction, and social participation were associated with lower depression scores. Social participation was a significant mediator of the relationship between caregiver status and depression. Caregivers reported significantly higher levels of affectionate support, emotional/informational support, positive social interaction, and social participation than non-caregivers. There were no between-group difference in depression scores.Discussion: The study provides support for the beneficial role of social participation in preserving caregiver mental health. Results are discussed in the context of policy and practice implications for caregivers in Canada.

Canadians Who Care: Social Networks and Informal Caregiving Among Lesbian, Gay, and Bisexual Older Adults in the Canadian Longitudinal Study on Aging.

Canada is experiencing population aging and evidence on the provision of care is based on data collected from majority populations. This analysis compared social networks and patterns of care provision between heterosexual and lesbian, gay, and bisexual (LGB) Canadians between the age of 45 and 85 years. Data were drawn from the Canadian Longitudinal Study on Aging (CLSA), a large national study of health and aging. The results from analysis of baseline data showed that LGB participants were less likely to have children and reported seeing their friends more recently than heterosexual participants. Gay and bisexual men were more likely to provide care support in comparison to heterosexual men. LGB participants were more likely to provide care to friends. The results highlight the importance of considering distinct social networks in the development of policy and practice approaches to support a diverse aging population.