Lower Risk Of Incident Dementia Research Articles

The impact of sodium-glucose co-transporter-2 inhibitors on dementia and cardiovascular events in diabetic patients with atrial fibrillation.

The effectiveness of sodium-glucose co-transporter-2 inhibitors (SGLT2i) on incident dementia in patients with diabetes and atrial fibrillation (AF) remains unknown. This study aimed to investigate the association between SGLT2i and the risk of incident dementia in diabetic patients with AF, and to explore the interactions with oral anticoagulants or dipeptidyl peptidase-4 inhibitors (DPP4i). We conducted a cohort study using Taiwan's National Health Insurance Research Database. Patients with diabetes and AFwithout a prior history of established cardiovascular diseases, were identified. Using propensity score matching, 810 patients receiving SGLT2i were matched with 1620 patients not receiving SGLT2i. The primary outcome was incident dementia, and secondary outcomes included composite cardiovascular events and mortality. After up to 5years of follow-up, SGLT2i use was associated with a significantly lower risk of incident dementia (hazard: 0.71, 95% confidence interval: 0.51-0.98), particularly vascular dementia (HR: 0.44, 95% CI: 0.24-0.82). SGLT2i was related to reduced risks of AF-related hospitalisation (HR: 0.72, 95% CI: 0.56-0.93), stroke (HR: 0.75, 95% CI: 0.60-0.94), and all-cause death (HR: 0.33, 95% CI: 0.24-0.44). The protective effects were consistent irrespective of the concurrent use of non-vitamin K antagonist oral anticoagulants (NOACs) or DPP4i. In diabetic patients with AF, SGLT2i was associated with reduced risks of incident dementia, AF-related hospitalisation, stroke, and all-cause death. The protective effects were independent of either concurrent use of NOACs or DPP4i.

Impact of sleep duration and sleep disturbances on the incidence of dementia and Alzheimer's disease: A 10-year follow-up study

The nature of the relationship between sleep problems and dementia remains unclear. This study investigated the relationship between sleep measures and dementia in older adults (≥ 65) using data from the English Longitudinal Study of Ageing (ELSA) and further investigated the causal association in Mendelian randomization (MR) analysis. In total of 7,223 individuals, 5.7 % developed dementia (1.7 % Alzheimer's disease (AD)) within an average of 8 (± 2.9) years. Cox regression models and MR were employed. Long sleep duration (>8 h) was associated with 64 % increased risk of incident dementia and 2-fold high risk of AD compared to ideal sleep duration (7–8 h). This association was particularly evident in older-older adults (≥70 years) and those who consumed alcohol. Short sleep duration (<7 h) was associated with lower risk of incident dementia among older-older but higher risk among younger-older adults. Sleep disturbances and perceived sleep quality were not associated with dementia or AD. The MR study did not reveal causal associations between sleep duration and dementia. These findings suggest that self-reported short sleep in younger-older and long sleep in older-older adults and those with frequent alcohol consumption are associated with dementia. Early detection of these sleep patterns may help identify individuals at higher dementia risk.

Statins and risks of dementia among patients with heart failure: a population-based retrospective cohort study in Hong Kong

Heart failure (HF) and dementia frequently co-exist with shared pathological mechanisms and risk factors. Our study aims to investigate the association between statin therapy and the risks of dementia and its subtypes among patients with HF. The Hong Kong Clinical Data Analysis and Reporting System database was interrogated to identify patients with incident HF diagnosis from 2004 to 2018, using ICD 9/ICD 10 codes. Inverse probability of treatment weighting (IPTW) was used to balance baseline covariates between statin users (N=54,004) and non-users (N=50,291). The primary outcomes were incident all-cause dementia, including subtypes of Alzheimer's disease, vascular dementia, and unspecified dementia. Cox proportional-hazard model with competing risk regression was performed to estimate the sub-distribution hazards ratio (SHR) with corresponding 95% confidence intervals (CI) of the risks of all-cause dementia and its subtypes that are associated with statin use. Of all eligible patients with HF (N=104,295), the mean age was 74.2±13.6 years old and 52,511 (50.3%) were male. Over a median follow-up of 9.9 years (interquartile range [IQR]: 6.4-13.0), 10,031 (9.6%) patients were diagnosed with dementia, among which Alzheimer's disease (N=2250), vascular dementia (N=1831), and unspecified dementia (N=5950) were quantified separately. After IPTW, statin use was associated with a 20% lower risk of incident dementia compared with non-use (multivariable-adjusted SHR 0.80, 95% CI 0.76-0.84). Stratified by subtypes of dementia, statin use was associated with a 28% lower risk of Alzheimer's disease (SHR 0.72, 95% CI 0.63-0.82), 18% lower risk of vascular dementia (SHR 0.82, 95% CI 0.70-0.95), and a 20% lower risk of unspecified dementia (SHR 0.80, 95% CI 0.75-0.85). In patients with HF, statin use was associated with a significantly lower risk of all-cause dementia and its subtypes, including Alzheimer's disease, vascular dementia, and unspecified dementia. Both randomized trials and experimental studies to validate the potential neuroprotective effect of statin are warranted. No funding was provided for this study.

Transition to healthier lifestyle associated with reduced risk of incident dementia and decreased hippocampal atrophy

BackgroundResearch has estimated the associations of lifestyle at one-time point with the risk of dementia and hippocampal volume, but the impact of lifestyle transition on dementia and hippocampal volume remains unclear. This study aims to examine the associations of lifestyle transition with the risk of dementia and hippocampal volume. MethodsBased on data from the UK Biobank, a weighted lifestyle score was constructed by incorporating six lifestyle factors. Within each baseline lifestyle group (i.e., healthy, intermediate, and unhealthy), lifestyle transition was classified into decline, maintenance, and improvement. Cox proportional hazard regression was used to estimate the association of lifestyle transition and incident dementia (N = 16,305). A multiple linear regression model was used to estimate the association between lifestyle transition and hippocampal volume (N = 5849). ResultsDuring a median follow-up period of 8.6 years, 120 (0.7 %) dementia events were documented. Among participants with healthy baseline lifestyles, the improvement group had a lower risk of incident dementia (HR: 0.18, 95 % CI: 0.04–0.81) and a larger hippocampal volume (β = 111.69, P = 0.026) than the decline group. Similar results were observed among participants with intermediate baseline lifestyles regarding dementia risk but not hippocampal volume. No benefits were observed in the improvement group among those with unhealthy baseline lifestyles. LimitationsA lower incidence of dementia than other cohort study and this may have resulted in an underestimation of the risk of dementia. ConclusionsEarlier transitions to healthier lifestyle were associated with reduced risk of incident dementia and decreased hippocampal atrophy.

NEW DIRECTIONS IN RESEARCH ON THE DYNAMICS OF PURPOSE IN LIFE AND COGNITIVE AGING

Abstract Purpose in life is the feeling that one’s life is goal oriented and has direction. There is converging, replicated evidence that having a greater sense of purpose in life is associated with better cognitive aging outcomes, including less cognitive decline across middle and older adulthood and lower risk of incident dementia. Emerging evidence also suggests that cognitive function may likewise support purpose in life. This symposium highlights recent advances on the dynamics between purpose in life and cognition across varying time scales and populations. Kim will describe the association between purpose in life and the maintenance of better cognitive function across six years in older adulthood and moderators of this association. Nelson and Bergeman will describe how cognitive function supported purpose in life through the uncertainty of the Covid-19 pandemic and moderators of this association. Pfund and colleagues will report on the bidirectional associations between purpose and cognition in older adulthood across four longitudinal samples using a coordinated data analytic approach. Finally, Sutin and colleagues will report on an ecological momentary assessment study that found that in moments when participants felt more purposeful, they had faster processing speed. Collectively, these talks emphasize the dynamic and often bidirectional relation between purpose in life and cognitive function. This work will help stimulate research to better understand purpose and cognitive health and how to leverage purpose in life for healthier cognitive aging outcomes.

Poor Diet and Lower Neuropsychological Performance in a rural setting: The Bogalusa Heart Study

AbstractBackgroundPoor diet has been associated with insidious onset dementia. The Alternate Healthy Eating Index (AHEI) can capture overall nutrient quality and individual/population eating behaviors. Higher adherence to AHEI has been associated with a lower risk of incident dementia and better cognitive function in late life. However, most evidence comes from high‐income populations from urban areas. Here, we examined the adherence to AHEI and its association with cognitive function in midlife among Black and White individuals from a community cohort in the rural, low SES area of Bogalusa, Louisiana.MethodThis cross‐sectional analysis considered 1,040 participants from the Bogalusa Heart Study (mean age 48.1 ± 61% female, 31% Black) with a complete neuropsychological (NP) assessment and food frequency questionnaires. (AHEI‐2010 score, range 0‐110). Regression models using GEE accounted for clustering effects of neighborhood factors/SES using census‐track level codes and estimated the association between quintiles (Q1‐Q5) of AHEI‐2010 and a global cognitive z‐score (GCS) and cognitive domains.ResultIndividuals in Q5 (healthiest) tended to be female (68%, p = 0.03), significantly older (49.3 ± 5, p&lt;0.001), with higher education (³ college 56%, p&lt;0.001), and AHEI‐2010 scores from 53.38‐79.2. Compared with participants in Q1. Those in Q5 had higher GCS [ß (95% CI):1.71 (0.85, 2.57); p&lt;0.001] after adjusting for age, sex, race, and the ACS‐Index of concentration at the extremes (to account for neighborhood‐level SES). Similarly, those with the healthiest diet had higher NP z‐scores within the domains of executive function, attention and speed processing information, and episodic memory. However, these associations were not significant after adjusting for education. (Table 1) For episodic memory, individuals in quintile 4 had higher NP z‐scores after adjusting for education [0.36 (0.07, 0.65); p = 0.01], and the trend across quintiles was also significant in all models and after adjusting for education [p = 0.03].ConclusionAs early as midlife, Black and White individuals from rural settings with greater adherence to healthy dietary patterns have better NP performance across different neurocognitive domains. These results strengthen previous evidence suggesting that diet quality may be a potential avenue of intervention to prevent cognitive decline and aid health disparities.

Statin and risk of dementia in patients with heart failure

Abstract Background Non-cardiovascular morbidity and mortality of heart failure (HF) patients rose immensely in recent years, with dementia emerging as one of the key comorbidities. Our study aims to investigate the association between statin use and the risks of dementia and its subtypes in HF patients. Methods 104 295 patients with incident HF diagnosis from 2004 to 2018 were identified and followed up until December 2020. Inverse probability of treatment weighting (IPTW) was used to balance baseline covariates between statin users (N = 54004) and non-users (N = 50291). The primary outcomes were incident all-cause dementia, including subtypes of Alzheimer’s disease, vascular dementia, and unspecified dementia. Cox proportional-hazard model with competing risk regression was performed to estimate the sub-distribution hazards ratio (SHR) with corresponding 95% confidence intervals (CI) of the risks of all-cause dementia and its subtypes that are associated with statin use. Results Of all eligible HF patients, the mean age was 74.2 ±13.6 years old and 52,511 (50.3%) were male. Over a median follow-up of 9.9 years (interquartile range [IQR]: 6.4 to 13.0), 10,031 (9.6%) patients were diagnosed with dementia, among which Alzheimer's disease (N = 2,250), vascular dementia (N = 1,831), and unspecified dementia (N = 5,950) were quantified separately. After IPTW, statin use was associated with a 20% lower risk of incident dementia compared with non-use (multivariable-adjusted SHR 0.80, 95% CI 0.76 to 0.84). Stratified by subtypes of dementia, statin use was associated with a 27% lower risk of Alzheimer’s disease (SHR 0.72, 95%CI 0.63 to 0.82), 18% lower risk of vascular dementia (SHR 0.82, 95%CI 0.70 to 0.95), and a 20% lower risk of unspecified dementia (SHR 0.80, 95%CI 0.75 to 0.85). Discussion In patients with HF, statin use was associated with a significantly lower risk of all-cause dementia and its subtypes, including Alzheimer’s disease, vascular dementia, and unspecified dementia.

Association Between Retinal Nerve Fiber Layer Thickness and Incident Dementia in the European Prospective Investigation into Cancer in Norfolk Cohort.

Retinal nerve fiber layer (RNFL) thickness may reflect cerebral status. This study assessed the relationship between RNFL thickness and incident all-cause dementia in the European Prospective Investigation into Cancer in Norfolk (EPIC-Norfolk) Eye Study. Glaucoma detection with variable corneal compensation (GDx-VCC) and Heidelberg Retinal Tomograph II (HRT II) derived global mean RNFL thickness from dementia-free participants at baseline within the EPIC-Norfolk Eye Study were analyzed. Incident dementia was identified through linkage to electronic medical records. Cox proportional hazard mixed-effects regression models adjusted for key confounders were used to examine the associations between RNFL thickness and incident dementia in four separate models. 6,239 participants were included with 322 cases of incident dementia and mean age of 67.5-years old, with 49.7% women (median follow-up 13.2-years, interquartile range (11.7 to 14.6 years). Greater RNFL thickness (GDx-VCC) was not significantly associated with a lower risk of incident dementia in the full adjusted model [HR per quartile increase 0.95; 95% CI 0.82-1.10]. Similarly, RNFL thickness assessed with HRT II was also not associated with incident dementia in any model (full adjusted model; HR per quartile increase: 1.06; [95% CI 0.93-1.19]. Gender did not modify any associations under study. GDx-VCC and HRT II derived RNFL thickness are unlikely to be useful predictors of incident dementia. Higher resolution optical imaging technologies may clarify whether there are useful relationships between neuro-retinal morphology and brain measures.

Catheter ablation and lower risk of incident dementia and mortality in older adults with atrial fibrillation.

Atrial fibrillation (AF) has consistently been associated with a higher risk of incident dementia. Observational evidence has suggested catheter ablation may be associated with a lower risk of dementia in patients with AF, but further research is needed. The objectives of this study were to use a global health research network to examine associations between catheter ablation, incident dementia and mortality in older adults with AF, and amongst subgroups by age, sex, co-morbidity status, and oral anticoagulant use. The research network primarily included healthcare organizations in the United States. This network was searched on 28th September 2022 for patients aged ≥65 years with a diagnosis of AF received at least 5 years prior to the search date. Cox proportional hazard models were run on propensity-score matched cohorts. After propensity score matching, 20,746 participants (mean age 68 years; 59% male) were included in each cohort with and without catheter ablation. The cohorts were well balanced for age, sex, ethnicity, co-morbidities, and cardiovascular medications received. The risk of dementia was significantly lower in the catheter ablation cohort (Hazard Ratio 0.52, 95% confidence interval: 0.45-0.61). The catheter ablation cohort also had a lower risk of all-cause mortality (Hazard Ratio 0.58, 95% confidence interval: 0.55-0.61). These associations remained in subgroup analyses in individuals aged 65-79 years, ≥80 years, males, females, participants who received OACs during follow-up, participants with paroxysmal and non-paroxysmal AF, and participants with and without hypertension, diabetes mellitus, ischemic stroke, chronic kidney disease and heart failure, including heart failure with preserved ejection fraction and heart failure with reduced ejection fraction. The observed lower risk of dementia and mortality with catheter ablation could be an important consideration when determining appropriate patient-centered rhythm control strategies for patients with AF. Further studies including data on the success of ablation are required.

Effects of adult education on cognitive function and risk of dementia in older adults: a longitudinal analysis.

Mid/late-life cognitive activities are associated with a lower rate of subsequent cognitive decline and lower subsequent dementia risk over time. In this study, we investigated the association between adult education class participation and subsequent cognitive decline and dementia risk over time after adjusting for baseline cognitive function and genetic risk of dementia, correcting for several potential confounding variables, using a large prospective cohort data of participants from the UK Biobank study followed from 2006 to 2010. The results revealed that participation in adult education classes at baseline was associated with greater subsequent retention of fluid intelligence score. Cox proportional hazard models revealed that subjects who participated in adult education classes showed a significantly lower risk of incident dementia 5 years after baseline compared with those that did not at baseline. In this study, we show that participation in adult education classes preceded greater retention of subsequent fluid intelligence and a lower risk of developing dementia after 5 years: this association did not change after adjusting for cognitive function at baseline or genetic predisposition to dementia. Accordingly, participation in such classes could reduce the risk of developing dementia.

Association between dairy intake and risk of incident dementia: the Ohsaki Cohort 2006 Study.

To investigate the association between dairy intake and risk of incident dementia in older adults. A longitudinal analysis of dairy intake with incident dementia was conducted using a cohort study of 11,637 non-disabled Japanese older adults aged ≥ 65years followed-up for up to 5.7years (mean: 5.0years). Data on milk, yogurt, and cheese intake were collected using a validated food frequency questionnaire. Total dairy intake was calculated as the sum of the daily intake of milk, yogurt, and cheese, which was sex-specifically categorized in quintiles. Dementia cases were retrieved from the public long-term care insurance database. Cox proportional hazards model was used to estimate multivariable hazard ratios (HRs) and 95% confidence intervals (95% CIs) for incident dementia. During 58,013 person-years of follow-up, 946 persons developed dementia. In the primary analysis, compare to the lowest quintile of total dairy intake, Q2 showed a slightly decreased incident dementia risk (HR for Q2 vs Q1: 0.90, 95% CI: 0.73-1.10) after fully adjusted for demographic, lifestyle, psychological, and nutritional factors, and diseases history. Compared to non-consumers of milk, those consuming for 1-2 times/month showed a lower risk of incident dementia (fully-adjusted HR: 0.76, 95% CI: 0.57-1.02). Daily yogurt consumers also had a reduced risk (fully-adjusted HR: 0.89, 95% CI: 0.74-1.09). But daily cheese consumers showed an increased risk of dementia (fully-adjusted HR: 1.28, 95% CI: 0.91-1.79). In the sensitivity analysis where we excluded dementia cases ascertained in the first 2years, results were consistent with those from the primary analysis and we further found that yogurt intake might be inversely associated with dementia risk (p for trend = 0.025). Low total dairy intake or low milk intake frequency might be associated with lower incident dementia risk, however daily cheese consumers seemed to have an increased risk. Our study also suggested a possible inverse dose-response association between yogurt consumption and dementia risk, but further studies are needed to confirm whether this benefit was from yogurt intake itself or as a part of a healthy dietary pattern.

Prevalent stroke, age of its onset, and post-stroke lifestyle in relation to dementia: A prospective cohort study.

The association of age at stroke onset with dementia and the role of post-stroke lifestyle on dementia risk remains unclear. We leveraged data of 496,251 dementia-free participants from UK Biobank and explored the relationship between age at stroke onset and incident dementia. Among 8328 participants with stroke history, we further investigated the association of a healthy lifestyle with risk of dementia. Participants with stroke history had a higher risk of dementia (hazard ratio [HR], 2.02). The association was stronger among participants with stroke onset at a younger age (≤50: HR, 2.63) compared with those at the age>50 years (50-60: HR, 2.17; ≥60: HR, 1.58). Among participants with stroke history, a favorable lifestyle was associated with a lower risk of incident dementia. Stroke onset in earlier life stage predicted a higher risk for dementia, but a favorable post-stroke lifestyle may protect against dementia.

Association of the Mediterranean Dietary Approaches to Stop Hypertension Intervention for Neurodegenerative Delay (MIND) Diet With the Risk of Dementia

Dementia threatens the well-being of older adults, making efforts toward prevention of great importance. To evaluate the association of the Mediterranean-Dietary Approaches to Stop Hypertension (DASH) Intervention for Neurodegenerative Delay (MIND) diet with the risk of dementia in 3 prospective studies and a meta-analysis. Cohort analyses included the Whitehall II study (WII), the Health and Retirement Study (HRS), and the Framingham Heart Study Offspring cohort (FOS), and the meta-analysis included 11 cohort studies. Participants were middle-aged and older women and men from WII in 2002 to 2004, HRS in 2013, and FOS in 1998 to 2001 without dementia at the study baseline. Data were analyzed from May 25 to September 1, 2022. MIND diet score was measured using food frequency questionnaires, and scores ranged from 0 to 15, with a higher score indicating higher adherence to the MIND diet. Incident all-cause dementia, with cohort-specific definitions. Included in this study were 8358 participants (mean [SD] age, 62.2 [6.0] years; 5777 male [69.1%]) from WII, 6758 participants (mean [SD] age, 66.5 [10.4] years; 3965 female [58.7%]) from HRS, and 3020 participants (mean [SD] age, 64.2 [9.1] years; 1648 female [54.6%]) from FOS. The mean (SD) baseline MIND diet score was 8.3 (1.4) in WII, 7.1 (1.9) in HRS, and 8.1 (1.6) in FOS. Over 166 516 person-years, a total of 775 participants (220 in WII, 338 in HRS, and 217 in FOS) developed incident dementia. In the multivariable-adjusted Cox proportional hazard model, higher MIND diet score was associated with lower risk of dementia (pooled hazard ratio [HR] for every 3-point increment, 0.83; 95% CI, 0.72-0.95; P for trend = .01; I2 = 0%). The associations were consistently observed in subgroups defined by sex, age, smoking status, and body mass index. In the meta-analysis of 11 cohort studies with 224 049 participants (5279 incident dementia cases), the highest tertile of MIND diet score was associated with lower risk of dementia compared with the lowest tertile (pooled HR, 0.83; 95% CI, 0.76-0.90; I2 = 35%). Results suggest that adherence to the MIND diet was associated with lower risk of incident dementia in middle-aged and older adults. Further studies are warranted to develop and refine the specific MIND diet for different populations.

Social connections and risk of incident mild cognitive impairment, dementia, and mortality in 13 longitudinal cohort studies of ageing.

Previous meta-analyses have linked social connections and mild cognitive impairment, dementia, and mortality. However, these used aggregate data from North America and Europe and examined a limited number of social connection markers. We used individual participant data (N=39271, Mage =70.67 (40-102), 58.86% female, Meducation =8.43 years, Mfollow-up =3.22 years) from 13 longitudinal ageing studies. A two-stage meta-analysis of Cox regression models examined the association between social connection markers with our primary outcomes. We found associations between good social connections structure and quality and lower risk of incident mild cognitive impairment (MCI); between social structure and function and lower risk of incident dementia and mortality. Only in Asian cohorts, being married/in a relationship was associated with reduced risk of dementia, and having a confidante was associated with reduced risk of dementia and mortality. Different aspects of social connections - structure, function, and quality - are associated with benefits for healthy aging internationally. Social connection structure (being married/in a relationship, weekly community group engagement, weekly family/friend interactions) and quality (never lonely) were associated with lower risk of incident MCI. Social connection structure (monthly/weekly friend/family interactions) and function (having a confidante) were associated with lower risk of incident dementia. Social connection structure (living with others, yearly/monthly/weekly community group engagement) and function (having a confidante) were associated with lower risk of mortality. Evidence from 13 longitudinal cohort studies of ageing indicates that social connections are important targets for reducing risk of incident MCI, incident dementia, and mortality. Only in Asian cohorts, being married/in a relationship was associated with reduced risk of dementia, and having a confidante was associated with reduced risk of dementia and mortality.

Circulating polyunsaturated fatty acids, fish oil supplementation, and risk of incident dementia: a prospective cohort study of 440,750 participants.

Cohort studies report inconsistent associations between omega-3 polyunsaturated fatty acids (n-3 PUFA) or fish oil and dementia risk. Furthermore, evidence relating omega-6 polyunsaturated fatty acids (n-6 PUFA) with dementia is scarce. Here, we included 440,750 dementia-free participants from UK Biobank to comprehensively investigate the associations between plasma levels of different types of PUFA, fish oil supplementation, and dementia risk. During a median follow-up of 9.25years, 7768 incident dementia events occurred. Higher plasma levels of five PUFA measures showed consistent associations with lower dementia risk (hazard ratios [95% confidence intervals] for per standard deviation increment of plasma concentrations 0.85 [0.81-0.89] for total PUFAs; 0.90 [0.86-0.95] for omega-3 PUFAs; 0.92 [0.87-0.96] for docosahexaenoic acid (DHA); 0.86 [0.82-0.90] for omega-6 PUFAs; 0.86 [0.82-0.90] for linoleic acid (LA); all p < 0.001). Compared with non-users, fish oil supplement users had a 7% decreased risk of developing all-cause dementia (0.93 [0.89-0.97], p = 0.002), and the relationship was partially mediated by plasma n-3 PUFA levels (omega-3 PUFAs: proportion of mediation = 57.99%; DHA: proportion of mediation = 56.95%). Furthermore, we observed significant associations of plasma n-3 PUFA levels and fish oil supplementation with peripheral immune markers that were related to dementia risk, as well as the positive associations of plasma PUFA levels with brain gray matter volumes and white matter microstructural integrity, suggesting they may affect dementia risk by affecting peripheral immunity and brain structure. Taken together, higher plasma PUFA levels and fish oil supplementation were associated with lower risk of incident dementia. This study may support the value of interventions to target PUFAs (specifically n-3 PUFAs) to prevent dementia.

Association between exercise habit changes and incident dementia after ischemic stroke

We aimed to investigate the effects of exercise habit changes on the risk of incident dementia after ischemic stroke using the Korean National Health Insurance Services Database. This study included 223,426 patients with a new diagnosis of ischemic stroke between 2010 and 2016 who underwent two serial ambulatory health checkups. The participants were divided into four categories according to their habit change or regular exercise: persistent non-exercisers, new exercisers, exercise dropouts, and exercise maintainers. The primary outcome was new diagnosis of dementia. Multivariate Cox proportional models were used to assess the effects of changes in exercise habits on the risk of incident dementia. After a median of 4.02 years of follow-up, 22,554 (10.09%) dementia cases were observed. After adjusting for covariates, exercise dropouts, new exercisers, and exercise maintainers were significantly associated with a lower risk of incident dementia than persistent non-exercisers (adjusted hazard ratio [aHR] 0.937; 95% confidence interval [CI] 0.905–0.970, aHR 0.876; 95% CI 0.843–0.909, aHR 0.705; 95% CI 0.677–0.734, respectively). The impact of changes in exercise habit was more prominent in the 40–65 years age group. An energy expenditure ≥ 1000 metabolic equivalents of task-min/wk post-stroke, regardless of pre-stroke physical activity status, was mostly associated with a lower risk of each outcome. In this retrospective cohort study, initiating or continuing moderate-to-vigorous exercise after ischemic stroke was associated with a lower risk of dementia development. Further, pre-stroke regular physical activity also reduced the risk of incident dementia. The promotion of exercise in ambulatory stroke patients may reduce their future risk of incident dementia.

Twenty-year prospective cohort study of the association between a Japanese dietary pattern and incident dementia: the NILS-LSA project

PurposeEvidence has suggested that adherence to a Japanese diet may be beneficial for health. However, its association with incident dementia remains unclear. The aim was to explore this association in older Japanese community-dwellers, taking apoprotein E genotype into consideration.MethodsA 20-year follow-up cohort study involving 1504 dementia-free older Japanese community-dwellers (aged 65–82 years) living in Aichi Prefecture, Japan, was conducted. Based on a previous study, a 9-component-weighted Japanese Diet Index (wJDI9) score (range − 1 to 12) was calculated using 3-day dietary record data and used as an indicator of adherence to a Japanese diet. Incident dementia was confirmed by the Long-term Care Insurance System certificate, and dementia events occurring within the first 5 years of follow-up were excluded. A multivariate-adjusted Cox proportional hazards model was used to calculate hazard ratios (HRs) and 95% confidence intervals (CIs) for incident dementia, and Laplace regression was used to estimate percentile differences (PDs) and 95% CIs (expressed in months) in age at incident dementia (i.e., dementia-free duration differences), according to tertiles (T1–T3) of wJDI9 scores.ResultsThe median (IQR) follow-up duration was 11.4 (7.8–15.1) years. During the follow-up period, 225 (15.0%) cases of incident dementia were identified. Because the smallest prevalence of incident dementia was 10.7% for the T3 group of wJDI9 scores, to avoid inaccurately estimating the dementia-free duration of participants in the T3 group, the 11th PDs in age at incident dementia between the T1 and T3 groups of wJDI9 scores were estimated. A higher wJDI9 score was associated with a lower risk of incident dementia and a longer dementia-free duration difference. The multivariate-adjusted HR (95% CI) and 11th PDs (95% CI) in age at incident dementia for participants in the T1 vs. T3 group were 1.00 (reference) vs. 0.58 (0.40, 0.86), and 0 (reference) vs. 36.7 (9.9, 63.4) months, respectively. Each 1-point increase of the wJDI9 score was associated with a 5% lower risk of incident dementia (P value = 0.033) and 3.9 (0.3, 7.6) additional months of dementia-free duration (P value = 0.035). No differences were seen in sex or smoking status (current smoker vs. non-current smoker) at baseline.ConclusionThese findings suggest that adherence to a Japanese diet defined by wJDI9 is associated with a lower risk of incident dementia in older Japanese community-dwellers, suggesting the benefit of the Japanese diet for dementia prevention.

Peak Expiratory Flow Predicts Incident Dementia in a Representative Sample of U.S. Older Adults: The National Health and Aging Trends Study (NHATS).

Dementia is an increasingly important public health problem with various risk factors. Respiratory function, measured via peak expiratory flow (PEF), may be a modifiable dementia risk factor. We investigated the association between PEF and incident dementia in 5 935 older adults from the National Health and Aging Trends Study (NHATS) from 2011 to 2014. Baseline PEF, expressed as a standardized residual (SR) percentile, was analyzed as a predictor of incident dementia using discrete-time proportional hazards models, while controlling for several health and sociodemographic covariates. After 14 332 person-years of follow-up, 9.0% (N = 536) had incident cases of dementia. Compared to the lowest PEF category (SR-percentile < 10%), the highest PEF category (SR-percentile ≥ 80%) had 49% lower risk of incident dementia (hazard ratio [HR] = 0.51; 95% confidence interval [CI; 0.37, 0.71]), and the second highest PEF category (SR-percentile 50%-80%) had 25% lower risk of incident dementia (HR = 0.75; 95% CI [0.56, 1.00]). A sensitivity analysis using multiple imputation to account for missing PEF measurements yielded similar associations with incident dementia. These associations suggest a dose-dependent relationship such that higher PEF categories were more protective against incident dementia. PEF may be considered as an easily administered, low-cost measure of respiratory function and a potentially modifiable dementia risk factor. Improving PEF may reduce dementia risk through vascular mechanisms, such as increased brain oxygenation. Future research should explore potential causal pathways between PEF and dementia.

Educational Quality and Incident All‐Cause Dementia: Black‐White Differences

AbstractBackgroundMeasurement of education via years of schooling may not be commensurate across racial and ethnic groups because of disparities in educational quality. We examine state‐level administrative school quality data and incident all‐cause dementia among Kaiser Permanente Northern California members who participated in a midlife survey and were aged 65 years or older at the start of follow‐up (1997).MethodsWe obtained educational attainment and birth state from surveys administered during 1964‐1973. We linked birth state with state‐level school quality measures (student‐teacher ratio, attendance rates, term length), categorized into tertiles using the overall sample. We obtained sex, race, and incident dementia diagnoses during follow‐up (1997‐2018) from electronic health records. Using race‐stratified Cox proportional hazards models (age as timescale), we estimated associations between each educational quality measure and dementia risk, adjusting for sex, birth region and educational attainment.ResultAmong 39,632 participants, 17% identified as Black, 44% reported less than high school education, and 7,206 individuals were diagnosed with dementia (mean follow‐up 13.5 years) (Table 1). Average educational quality was lower among Black participants (Table 1). Higher attendance rates and longer term length were associated with lower dementia risk among both racial groups (Figure 1, Table 2). Among Black participants, for example, highest versus lowest attendance rate tertile was associated with 50% lower risk (adjusted hazard ratio [HR]: 0.50, 95% confidence interval [CI]: 0.38‐0.67). Lower student‐teacher ratio was associated with lower risk only among White participants. The association between higher educational quality and lower dementia risk was stronger among Black than White participants for attendance rates and term length (race‐school quality interaction term p‐value: 0.05 and 0.03, respectively), but not significantly different for student‐teacher ratio.ConclusionIn both Black and White participants, higher school quality is associated with lower risk of incident dementia, even after adjusting for educational attainment. The associations were stronger among Black participants for attendance rates and term length. Educational disparities may partially be explained by lower average educational quality among Black participants, limiting its protective effects.

Association between reproductive factors in women and risk of brain ageing and dementia

AbstractBackgroundWomen have a higher prevalence of dementia than men. We determined the association between female reproductive factors and risk of cognitive outcomes, including incident dementia, in a community‐based sample of cognitively healthy individuals.MethodLifetime reproductive factors including age of menarche, age of menopause, reproductive lifespan (age of menopause minus age of menarche), number of live births, post‐menopausal hormone replacement therapy use, and serum estradiol and estrone concentrations were measured in 796 dementia‐free women [mean age 68.4 (SD 5.7) yr] from the Framingham Heart Study Offspring cohort at examination cycle seven (1998‐2001). We related reproductive factors to subsequent risk of incident dementia. Structural MRI brain measures and neurocognitive test performance were included as secondary outcomes.ResultDuring a median 10 [Q1‐Q3, 8.04‐10.0] year follow‐up, 138 participants developed dementia. On Cox proportional‐hazards analysis adjusting for age and education, a longer reproductive lifespan was associated with a reduced risk of incident dementia (HR 0.94, 95% CI 0.91‐0.98, p = 0.004) while earlier age of menopause of ≤49 vs 50‐51 years was associated with an increased dementia risk (HR 2.56, 95% CI 1.12‐5.88, p = 0.027). Earlier menopause (≤49 versus 50‐51 years) was cross‐sectionally associated with lower hippocampal volume (β±SE, ‐0.123±0.057, p = 0.03). Compared to no live births, 1‐2 live births (5.85±2.03, p = 0.004) and ≥3 live births (5.17±2.06, p = 0.01) were associated with greater total cerebral brain volume. Use of post‐menopausal HRT (0.15±0.055, p = 0.007) and elevated serum estradiol (0.058±0.027, p = 0.03) and estrone concentrations (0.078±0.029, p = 0.006) were cross‐sectionally associated with improved abstract reasoning (Similarities test). Compared to no live births, 1‐2 live births (0.20±0.08, p = 0.018) and ≥3 live births (0.25±0.08, p = 0.003) were also associated with superior visuospatial performance.ConclusionGreater exposure to estrogen throughout a woman’s reproductive life was associated with a lower risk of incident dementia and cross‐sectionally associated with larger brain volumes and enhanced cognitive performance. Our results suggest positive cognitive benefits of greater lifetime estrogen exposure and highlight the potential role of estrogen exposure in modifying the risk of dementia.