Association Between Accelerometer-Assessed Physical Activity and Cognitive Function in Older Adults: A Cross-Sectional Study.

OBJECTIVE: Research suggests that physical activity (PA) improves cognitive function across various domains. However, the specific role of different PA measures, including step count, remains to be explored. Our aim was to assess the correlation between objectively measured PA and cognitive function. METHODS: We included 663 adults, aged ≥66 years, from the Swedish SNAC-K study (2016-2019). Global cognition and three cognitive domains (processing speed, executive function, and episodic memory) were assessed with validated tests. PA was measured through ActivPAL3 accelerometers. We applied age-stratified (<70 vs. ≥80 years), multi-adjusted, quantile regression to examine the cross-sectional associations between cognitive function and PA, considering steps/day and time spent in moderate-to-vigorous PA (MVPA). RESULTS: Each 1000-step increment (ß = 0.04; 95% CI: 0.01, 0.07) and each additional hour of MVPA per day (ß = 0.28; 95% CI: 0.02, 0.54) were correlated with better processing speed in the youngest-old, but not in the oldest-old. When further stratifying by MVPA (<60 min vs. ≥60 min/week), each 1000-step increment was associated with better processing speed in the youngest-old, regardless of their MVPA levels. CONCLUSION: Our study links accelerometer-assessed PA (steps and MVPA) with better processing speed in the youngest-old adults. Step count correlated with processing speed regardless of intensity. Further research is needed to determine the directionality of these associations.

Sex differences in the impact of lower respiratory tract infections on older adults' health trajectories: a population-based cohort study.

BACKGROUND: Lower respiratory tract infections (LRTIs) are a major global health concern, particularly among older adults, who have an increased risk of poorer health outcomes that persist beyond the acute infectious episode. We aimed to investigate the mid-term (up to 7 years) and long-term (up to 12 years) effects of LRTIs on the objective health status trajectories of older adults, while also considering potential sex differences. METHODS: Cohort data of adults aged ≥ 60 years from the Swedish National study of Aging and Care in Kungsholmen (SNAC-K) collected between 2001 and 2016 was analyzed. Information on LRTIs was obtained from the Swedish National Patient Register, and objective health status was assessed using the Health Assessment Tool (HAT) which incorporates indicators of mild and severe disability, cognitive and physical functioning, and multimorbidity. The LRTI-exposed and -unexposed participants were matched using propensity score matching based on an expansive list of potential confounders. Mixed linear models were used to analyze the association between LRTIs and changes in HAT scores. RESULTS: The study included 2796 participants, 567 of whom were diagnosed with a LRTI. LRTIs were independently associated with an excess annual decline of 0.060 (95% CI: -0.107, -0.013) in the HAT score over a 7-year period. The associations were stronger among males, who experienced an excess annual decline of 0.108 (95% CI: -0.177, -0.039) in up to 7-years follow-up, and 0.097 (95% CI: -0.173, -0.021) in up to 12-years follow-up. The associations were not statistically significant among females in either follow-up period. CONCLUSION: LRTIs, even years after the acute infectious period, seem to have a prolonged negative effect on the health of older adults, particularly among males. Preventative public health measures aimed at decreasing LRTI cases among older adults could help in preserving good health and functioning in old age.

Patterns of multimorbidity in primary care electronic health records: A systematic review.

Background: Multimorbidity, the coexistence of multiple chronic conditions in an individual, is a complex phenomenon that is highly prevalent in primary care settings, particularly in older individuals. This systematic review summarises the current evidence on multimorbidity patterns identified in primary care electronic health record (EHR) data. Methods: Three databases were searched from inception to April 2022 to identify studies that derived original multimorbidity patterns from primary care EHR data. The quality of the included studies was assessed using a modified version of the Newcastle-Ottawa Quality Assessment Scale. Results: Sixteen studies were included in this systematic review, none of which was of low quality. Most studies were conducted in Spain, and only one study was conducted outside of Europe. The prevalence of multimorbidity (i.e. two or more conditions) ranged from 14.0% to 93.9%. The most common stratification variable in disease clustering models was sex, followed by age and calendar year. Despite significant heterogeneity in clustering methods and disease classification tools, consistent patterns of multimorbidity emerged. Mental health and cardiovascular patterns were identified in all studies, often in combination with diseases of other organ systems (e.g. neurological, endocrine). Discussion: These findings emphasise the frequent coexistence of physical and mental health conditions in primary care, and provide useful information for the development of targeted preventive and management strategies. Future research should explore mechanisms underlying multimorbidity patterns, prioritise methodological harmonisation to facilitate the comparability of findings, and promote the use of EHR data globally to enhance our understanding of multimorbidity in more diverse populations.

Protein Intake and Mortality in Older Adults With Chronic Kidney Disease.

Importance: Avoiding high protein intake in older adults with chronic kidney disease (CKD) may reduce the risk of kidney function decline, but whether it can be suboptimal for survival is not well known. Objective: To estimate the associations of total, animal, and plant protein intake with all-cause mortality in older adults with mild or moderate CKD and compare the results to those of older persons without CKD. Design, Setting, and Participants: Data from 3 cohorts (Study on Cardiovascular Health, Nutrition and Frailty in Older Adults in Spain 1 and 2 and the Swedish National Study on Aging and Care in Kungsholmen [in Sweden]) composed of community-dwelling adults 60 years or older were used. Participants were recruited between March 2001 and June 2017 and followed up for mortality from December 2021 to January 2024. Those with no information on diet or mortality, with CKD stages 4 or 5, or undergoing kidney replacement therapy and kidney transplant recipients were excluded. Data were originally analyzed from June 2023 to February 2024 and reanalyzed in May 2024. Exposures: Cumulative protein intake, estimated via validated dietary histories and food frequency questionnaires. Main Outcomes and Measures: The study outcome was 10-year all-cause mortality, ascertained with national death registers. Chronic kidney disease was ascertained according to estimated glomerular filtration rates, urine albumin excretion, and diagnoses from medical records. Results: The study sample consisted of 8543 participants and 14 399 observations. Of the 4789 observations with CKD stages 1 to 3, 2726 (56.9%) corresponded to female sex, and mean (SD) age was 78.0 (7.2) years. During the follow-up period, 1468 deaths were recorded. Higher total protein intake was associated with lower mortality among participants with CKD; adjusted hazard ratio (HR) for 1.00 vs 0.80 g/kg/d was 0.88 (95% CI, 0.79-0.98); for 1.20 vs 0.80 g/kg/d, 0.79 (95% CI, 0.66-0.95); and for 1.40 vs 0.80 g/kg/d, 0.73 (95% CI, 0.57-0.92). Associations with mortality were comparable for plant and animal protein (HRs, 0.80 [95% CI, 0.65-0.98] and 0.88 [95% CI, 0.81-0.95] per 0.20-g/kg/d increment, respectively) and for total protein intake in participants younger than 75 years vs 75 years or older (HRs, 0.94 [95% CI, 0.85-1.04] and 0.91 [95% CI, 0.85-0.98] per 0.20-g/kg/d increment in total protein intake, respectively). However, the hazards were lower among participants without CKD than in those with CKD (HRs, 0.85 [95% CI, 0.79-0.92] and 0.92 [95% CI, 0.86-0.98] per 0.20-g/kg/d increment, respectively; P = .02 for interaction). Conclusions and Relevance: In this multicohort study of older adults, higher intake of total, animal, and plant protein was associated with lower mortality in participants with CKD. Associations were stronger in those without CKD, suggesting that the benefits of proteins may outweigh the downsides in older adults with mild or moderate CKD.

Social network and severe lower respiratory tract infections in older adults: findings from a Swedish longitudinal population-based study.

OBJECTIVES: To investigate the association between social network and the risk and prognosis of severe lower respiratory tract infections (LRTIs) in older adults. METHODS: Data from Swedish hospital records were matched with the Swedish National Study on Aging and Care in Kungsholmen (SNAC-K). Social network was operationalized as social connections and social support, based on different self-reported variables, and categorized as low, medium, and high. The risk of severe LRTI and related outcomes were assessed using Cox, Poisson, and logistic regression models where appropriate. RESULTS: A total of 362 individuals experienced LRTI-related hospitalizations between 2001 and 2016 (479 total hospitalizations). High levels of social support decreased the hazard of incident LRTI by 29% (hazard ratio 0.71, 95% confidence interval [CI] 0.52-0.96), the hospital length of stay by 21% (incidence rate ratio 0.79, 95% CI 0.65-0.97), and the risk of 30-day mortality by 92% (odds ratio 0.08, 95% CI 0.01-0.68), but was a risk factor for 30-day readmission (odds ratio 3.16, 95% CI 1.38-7.24). High levels of social connections were associated with a higher risk of incident LRTI in women and those with dementia and/or slow walking speed (Pinteraction <0.05). CONCLUSION: Older individuals' quality of social support seems to be a stronger determinant of LRTI incidence and prognosis than the quantity of their social connections. These findings may inform evidence-based policies aimed at preventing LRTIs in older adults.

Variability in perceived burden and health trajectories among older caregivers: a population-based study in Sweden.

BACKGROUND: The negative effects of informal caregiving are determined by the characteristics of the caregiver-care receiver dyad and the context of care. In this study, we aimed to identify which subgroups of older informal caregivers (1) experience the greatest subjective burden and (2) incur a faster decline in objective health status. METHODS: From a total of 3363 older participants in the Swedish National study on Aging and Care in Kungsholmen (SNAC-K), we identified 629 informal caregivers (19.2%, mean age 69.9 years). Limitations to life and perceived burden were self-reported, and objective health status was quantified using the comprehensive clinical and functional Health Assessment Tool (HAT) score (range: 0-10). Ordered logistic regressions and linear mixed models were used to estimate the associations between caregiving-related exposures and subjective outcomes (cross-sectionally) and objective health trajectories (over 12 years), respectively. RESULTS: Having a dual role (providing and receiving care simultaneously), caring for a spouse, living in the same household as the care receiver and spending more hours on caregiving were associated with more limitations and burden. In addition, having a dual role (ß=-0.12, 95% CI -0.23 to -0.02) and caring for a spouse (ß=-0.08, 95% CI -0.14 to -0.02) were associated with a faster HAT score decline. Being female and having a poor social network were associated with an exacerbation of the health decline. CONCLUSIONS: Both the heterogeneity among caregivers and the related contextual factors should be accounted for by policymakers as well as in future research investigating the health impact of informal caregiving.

Association Between Concerns About Falling and Risk of Injurious Falls in Older Adults: The Role of Balance Impairment.

OBJECTIVES: We aimed to examine the extent to which concerns about falling are associated with the risk of injurious falls in older adults, and to explore the role of balance impairment in this association. DESIGN: Prospective study with a 5-year follow-up. SETTING AND PARTICIPANTS: Participants were 1281 people, aged ≥60 years (62.5% women), from the Swedish National Study on Aging and Care in Kungsholmen. METHODS: Data on injurious falls during 5 years of follow-up was obtained from national registers. Cox and Laplace regression models were applied to examine injurious falls in relation to concerns about falling (binary variable), balance impairment (one-leg balance test), or an indicator variable with 4 mutually exclusive categories based on the presence of concerns about falling and balance impairment. RESULTS: There was no statistically significant association between concerns about falling and injurious falls in the total sample when adjusting for covariates. We found significant interactions of concerns about falling with balance impairment and age (<70 vs ≥80 years), so that the association between concerns about falling and injurious falls was more evident in people with better balance and the younger-old participants (P < .05). Having only concerns about falling [hazard ratio (HR) 2.06, 95% CI 1.22, 3.48], only balance impairment (HR 2.22, 95% CI 1.38, 3.56), or both (HR 2.35, 95% CI 1.45, 3.82) were associated with an increased risk of injurious falls compared to those with neither concerns about falling nor balance impairment. CONCLUSIONS AND IMPLICATIONS: Our results suggest that concerns about falling may increase the risk of injurious falls, especially among younger-old people or those without objective balance impairment.

Concordance and Discrepancies Among 5 Creatinine-Based Equations for Assessing Estimated Glomerular Filtration Rate in Older Adults.

Importance: There is uncertainty as to which estimated glomerular filtration rate (eGFR) equation should be used among older adults. Objective: To compare the 5 most commonly used creatinine-based eGFR equations in older adults, quantifying the concordance among the equations, comparing their discriminative capacity in regards to 15-year mortality, and identifying sources of potential discrepancies. Design, Setting, and Participants: This cohort study used data from the Swedish National Study on Aging and Care in Kungsholmen (SNAC-K), a longitudinal study of adults aged 60 years or older in Sweden. Participants were recruited between 2001 and 2004 and followed up for mortality until December 2016. Participants missing creatinine values were excluded. Data were originally analyzed March through July 2022, and were rerun in January 2023. Exposures: Five creatinine-based equations were considered: Modification of Diet in Renal Disease (MDRD), 2009 Chronic Kidney Disease Epidemiological Collaboration (CKD-EPI), Revised Lund-Malmö (RLM), Berlin Initiative Study (BIS), and European Kidney Function Consortium (EKFC). Main Outcomes and Measures: Concordance between equations was quantified using Cohen κ. Discriminative capacity for mortality was quantified using area under the receiver operating characteristic curve (AUC) and the Harrel C statistic. Calf circumference, body mass index (BMI), and age were explored as correlates of discrepancies. Results: The study sample consisted of 3094 older adults (1972 [63.7%] female; median [IQR] age, 72 [66-81] years). Cohen κ between dyads of equations ranged from 0.42 to 0.91, with poorest concordance between MDRD and BIS, and best between RLM and EKFC. MDRD and CKD-EPI provided higher estimates of GFR compared with the other equations. The best mix of AUC and Harrel C statistic was observed for BIS (0.80 and 0.73, respectively); however, the prognostic accuracy for death decreased among those aged over 78 years and those with low calf circumference. Differences between equations were inconsistent across levels of calf circumference, BMI, and age. Conclusions and Relevance: In this cohort study, we found that eGFR equations were not interchangeable when assessing kidney function. BIS outperformed other equations in predicting mortality; however, its discriminative capacity was reduced in subgroup analyses. Clinicians should consider these discrepancies when monitoring kidney function in old age.

COVID-19 collateral damage-psychological burden and behavioural changes among older adults during the first outbreak in Stockholm, Sweden: a cross-sectional study.

OBJECTIVES: To explore the indirect negative effects of COVID-19 restrictions (collateral damage) on the lives and health of older adults living in central Stockholm, and to characterise the sociodemographic profile of those with the highest susceptibility to this damage. DESIGN: Cross-sectional study. SETTING: District of Kungsholmen in Stockholm, Sweden. PARTICIPANTS: Older adults aged 68 years and above (n=1231) who participated in the ad hoc COVID-19-related phone questionnaire administered by trained staff between May and June 2020 and who had previously attended the regular follow-up assessment of the Swedish National study on Aging and Care in Kungsholmen (SNAC-K) during 2016-2019. PRIMARY AND SECONDARY OUTCOME MEASURES: Three dimensions of collateral damage: psychological burden (feelings of worry, stress and loneliness), reductions in social and physical activities, and reductions in medical and social care use since the beginning of the pandemic. Logistic regression models were used to test the association between age, sex, education and living arrangement, and the risk of collateral damage. RESULTS: Vast majority of participants adhered to the national public health recommendations, with over three-quarters practising self-isolation (n=928). Half of the sample reported psychological burden, 55.3% reported reductions in social or physical activity, and 11.3% reported decreased medical or social care use. Over three quarters of participants (77.8%) were affected by at least one of the three collateral damage dimensions. Female sex was the strongest sociodemographic predictor of both individual and co-occurring dimensions of collateral damage. CONCLUSIONS: COVID-19 and its restrictions during the first half of 2020 had a negative effect on the health and lives of a majority of the elderly living in central Stockholm. Women were at a higher risk of these negative consequences. We emphasise the need for predefined, evidence-based interventions to support those who are most susceptible to these consequences, both during the pandemic and once the outbreak is overcome.

The role of glucose in cognition, risk of dementia, and related biomarkers in individuals without type 2 diabetes mellitus or the metabolic syndrome: A systematic review of observational studies.

BACKGROUND: Excessive blood glucose promotes neuropathological cognitive decline in individuals with type 2 diabetes mellitus and the metabolic syndrome, but no systematic synthesis of the evidence for the same association exists in individuals without these conditions. OBJECTIVES: To systematically review studies exploring the role of glucose on cognition, dementia risk, and related biomarkers in adults without diabetes or metabolic syndrome. DATA SOURCES: We searched databases from inception until July 2021 and manually searched the reference lists of included studies. Risk of bias was assessed using the Joanna Briggs Institute tool. RESULTS: We found 46 observational studies including approximately 98,216 participants. Substantial heterogeneity in study results precluded drawing definitive conclusion whether blood glucose levels are associated with cognition or dementia risk. Higher blood glucose, however, was associated with greater amyloid burden, brain atrophy, and reduced cortical thickness. CONCLUSIONS AND IMPLICATIONS: High glucose concentrations in blood may exacerbate dementia-related neuropathology but whether this translates into pathological cognitive decline or elevate dementia risk later in life remains unclear.

Influence of Active and Healthy Ageing on Quality of Life Changes: Insights from the Comparison of Three European Countries.

This study aimed to analyze the determinants of quality of life (QoL) in older people in three European countries (Portugal, Spain and Sweden). A sample of 7589 participants in waves 4 (2011) and 6 (2015) of the Survey on Health, Aging, and Retirement in Europe (SHARE) project, aged 50 and over and living in Portugal, Spain and Sweden, was included. The CASP-12 scale was used to measure QoL. A principal component analysis was performed to group preselected variables related to active and healthy ageing into the dimensions of health, social participation, and lifelong learning. A linear regression model was built using the change in CASP-12 scores over the 4-year follow-up as the dependent variable, including the interactions between country and each independent variable in the model. After four years, the average QoL increased in Portugal (difference = 0.8, p < 0.001), decreased in Spain (-0.8, p < 0.001), and remained constant in Sweden (0.1, p = 0.408). A significant country-participation component interaction (p = 0.039) was found. In Spain, a higher participation (ß = 0.031, p = 0.002) was related to a higher QoL improvement at 4 years, but not in Sweden or Portugal. Physical health and emotional components (ß = 0.099, p < 0.001), functional ability (ß = 0.044, p = 0.023), and cognitive and sensory ability (ß = 0.021, p = 0.026) were associated with QoL changes over time in all countries. The country-specific associations between health, social participation and QoL should be taken into account when developing public health policies to promote QoL among European older people.

Are Loneliness and Social Isolation Associated with Quality of Life in Older Adults? Insights from Northern and Southern Europe.

PURPOSE: Loneliness and social isolation have detrimental effects on health in old age; however, the prospective associations with quality of life (QoL) remain unclear. Furthermore, despite the existence of a European north-south gradient in the distribution of loneliness and social isolation, little is known whether the associations are context-specific. We investigated the relationships between loneliness, social isolation and QoL of older adults residing in the North (Sweden) and South (Spain) of Europe. METHODS: Study sample consisted of 2995 Swedish and 4154 Spanish older adults who participated in waves six and seven of the Study on Health, Aging and Retirement in Europe (SHARE). Loneliness and social isolation were measured at the baseline, and QoL was measured at the baseline and follow-up using CASP-12. Prospective associations were assessed via multivariate linear regression. RESULTS: In Sweden, subjects with higher vs. lower loneliness had 1.01 (95% CI: -1.55, -0.40) units lower QoL, while every standard deviation increase in social isolation was associated with a 0.27 (95% CI: -0.42, -0.09)-unit decrease in QoL. In Spain, every standard deviation increase in social isolation was associated with a 0.66 (95% CI: -1.11, -0.22)-unit decrease in QoL. The association was stronger in subjects aged ≤65 years old and those with no chronic diseases. The association with loneliness was not statistically significant in Spain. CONCLUSION: Loneliness and social isolation are prospectively associated with decreased QoL among older adults, yet the associations are contextually bound. Future interventions should target both exposures, among others, in order to increase QoL in this group.