Browsing by Author "Sachdev PS"

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    Associations between social connections and cognition: a global collaborative individual participant data meta-analysis
    (Elsevier B.V, 2022-11) Samtani S; Mahalingam G; Lam BCP; Lipnicki DM; Lima-Costa MF; Blay SL; Castro-Costa E; Shifu X; Guerchet M; Preux P-M; Gbessemehlan A; Skoog I; Najar J; Rydberg Sterner T; Scarmeas N; Kim K-W; Riedel-Heller S; Röhr S; Pabst A; Shahar S; Numbers K; Ganguli M; Jacobsen E; Hughes TF; Crowe M; Ng TP; Maddock J; Marseglia A; Mélis R; Szcześniak D; Wiegelmann H; Vernooij-Dassen M; Jeon Y-H; Sachdev PS; Brodaty H; SHARED consortium for the Cohort Studies of Memory in an International Consortium (COSMIC)
    Background Poor social connections (eg, small networks, infrequent interactions, and loneliness) are modifiable risk factors for cognitive decline. Existing meta-analyses are limited by reporting aggregate responses, a focus on global cognition, and combining social measures into single constructs. We aimed to investigate the association between social connection markers and the rate of annual change in cognition (ie, global and domain-specific), as well as sex differences, using an individual participant data meta-analysis. Methods We harmonised data from 13 longitudinal cohort studies of ageing in North America, South America, Europe, Africa, Asia, and Australia. Studies were eligible for inclusion if they had baseline data for social connection markers and at least two waves of cognitive scores. Follow-up periods ranged from 0 years to 15 years across cohorts. We included participants with cognitive data for at least two waves and social connection data for at least one wave. We then identified and excluded people with dementia at baseline. Primary outcomes were annual rates of change in global cognition and cognitive domain scores over time until final follow-up within each cohort study analysed by use of an individual participant data meta-analysis. Linear mixed models within cohorts used baseline social connection markers as predictors of the primary outcomes. Effects were pooled in two stages using random-effects meta-analyses. We assessed the primary outcomes in the main (partially adjusted) and fully adjusted models. Partially adjusted models controlled for age, sex, and education; fully adjusted models additionally controlled for diabetes, hypertension, smoking, cardiovascular risk, and depression. Findings Of the 40 006 participants in the 13 cohort studies, we excluded 1392 people with dementia at baseline. 38 614 individual participants were included in our analyses. For the main models, being in a relationship or married predicted slower global cognitive decline (b=0·010, 95% CI 0·000–0·019) than did being single or never married; living with others predicted slower global cognitive (b=0·007, 0·002–0·012), memory (b=0·017, 0·006–0·028), and language (b=0·008, 0·000–0·015) decline than did living alone; and weekly interactions with family and friends (b=0·016, 0·006–0·026) and weekly community group engagement (b=0·030, 0·007–0·052) predicted slower memory decline than did no interactions and no engagement. Never feeling lonely predicted slower global cognitive (b=0·047, 95% CI 0·018–0·075) and executive function (b=0·047, 0·017–0·077) decline than did often feeling lonely. Degree of social support, having a confidante, and relationship satisfaction did not predict cognitive decline across global cognition or cognitive domains. Heterogeneity was low (I2=0·00–15·11%) for all but two of the significant findings (association between slower memory decline and living with others [I2=58·33%] and community group engagement, I2=37·54–72·19%), suggesting robust results across studies. Interpretation Good social connections (ie, living with others, weekly community group engagement, interacting weekly with family and friends, and never feeling lonely) are associated with slower cognitive decline. Funding EU Joint Programme–Neurodegenerative Disease Research grant, funded by the National Health and Medical Research Council Australia, and the US National Institute on Aging of the US National Institutes of Health.
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    Determinants of cognitive performance and decline in 20 diverse ethno-regional groups: A COSMIC collaboration cohort study
    (Public Library of Science (PLoS), 2019-07) Lipnicki DM; Makkar SR; Crawford JD; Thalamuthu A; Kochan NA; Lima-Costa MF; Castro-Costa E; Ferri CP; Brayne C; Stephan B; Llibre-Rodriguez JJ; Llibre-Guerra JJ; Valhuerdi-Cepero AJ; Lipton RB; Katz MJ; Derby CA; Ritchie K; Ancelin M-L; Carrière I; Scarmeas N; Yannakoulia M; Hadjigeorgiou GM; Lam L; Chan W-C; Fung A; Guaita A; Vaccaro R; Davin A; Kim KW; Han JW; Suh SW; Riedel-Heller SG; Roehr S; Pabst A; van Boxtel M; Köhler S; Deckers K; Ganguli M; Jacobsen EP; Hughes TF; Anstey KJ; Cherbuin N; Haan MN; Aiello AE; Dang K; Kumagai S; Chen T; Narazaki K; Ng TP; Gao Q; Nyunt MSZ; Scazufca M; Brodaty H; Numbers K; Trollor JN; Meguro K; Yamaguchi S; Ishii H; Lobo A; Lopez-Anton R; Santabárbara J; Leung Y; Lo JW; Popovic G; Sachdev PS; for Cohort Studies of Memory in an International Consortium (COSMIC)
    Background With no effective treatments for cognitive decline or dementia, improving the evidence base for modifiable risk factors is a research priority. This study investigated associations between risk factors and late-life cognitive decline on a global scale, including comparisons between ethno-regional groups. Methods and findings We harmonized longitudinal data from 20 population-based cohorts from 15 countries over 5 continents, including 48,522 individuals (58.4% women) aged 54–105 (mean = 72.7) years and without dementia at baseline. Studies had 2–15 years of follow-up. The risk factors investigated were age, sex, education, alcohol consumption, anxiety, apolipoprotein E ε4 allele (APOE*4) status, atrial fibrillation, blood pressure and pulse pressure, body mass index, cardiovascular disease, depression, diabetes, self-rated health, high cholesterol, hypertension, peripheral vascular disease, physical activity, smoking, and history of stroke. Associations with risk factors were determined for a global cognitive composite outcome (memory, language, processing speed, and executive functioning tests) and Mini-Mental State Examination score. Individual participant data meta-analyses of multivariable linear mixed model results pooled across cohorts revealed that for at least 1 cognitive outcome, age (B = −0.1, SE = 0.01), APOE*4 carriage (B = −0.31, SE = 0.11), depression (B = −0.11, SE = 0.06), diabetes (B = −0.23, SE = 0.10), current smoking (B = −0.20, SE = 0.08), and history of stroke (B = −0.22, SE = 0.09) were independently associated with poorer cognitive performance (p < 0.05 for all), and higher levels of education (B = 0.12, SE = 0.02) and vigorous physical activity (B = 0.17, SE = 0.06) were associated with better performance (p < 0.01 for both). Age (B = −0.07, SE = 0.01), APOE*4 carriage (B = −0.41, SE = 0.18), and diabetes (B = −0.18, SE = 0.10) were independently associated with faster cognitive decline (p < 0.05 for all). Different effects between Asian people and white people included stronger associations for Asian people between ever smoking and poorer cognition (group by risk factor interaction: B = −0.24, SE = 0.12), and between diabetes and cognitive decline (B = −0.66, SE = 0.27; p < 0.05 for both). Limitations of our study include a loss or distortion of risk factor data with harmonization, and not investigating factors at midlife. Conclusions These results suggest that education, smoking, physical activity, diabetes, and stroke are all modifiable factors associated with cognitive decline. If these factors are determined to be causal, controlling them could minimize worldwide levels of cognitive decline. However, any global prevention strategy may need to consider ethno-regional differences.
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    Does parity matter in women’s risk of dementia? A COSMIC collaboration cohort study
    (BMC, 2020-08-05) Bae JB; Lipnicki DM; Han JW; Sachdev PS; Kim TH; Kwak KP; Kim BJ; Kim SG; Kim JL; Moon SW; Park JH; Ryu S-H; Youn JC; Lee DY; Lee DW; Lee SB; Lee JJ; Jhoo JH; Llibre-Rodriguez JJ; Llibre-Guerra JJ; Valhuerdi-Cepero AJ; Ritchie K; Ancelin M-L; Carriere I; Skoog I; Najar J; Sterner TR; Scarmeas N; Yannakoulia M; Dardiotis E; Meguro K; Kasai M; Nakamura K; Riedel-Heller S; Roehr S; Pabst A; van Boxtel M; Köhler S; Ding D; Zhao Q; Liang X; Scazufca M; Lobo A; De-la-Cámara C; Lobo E; Kim KW; for Cohort Studies of Memory in an International Consortium (COSMIC)
    Background Dementia shows sex difference in its epidemiology. Childbirth, a distinctive experience of women, is associated with the risk for various diseases. However, its association with the risk of dementia in women has rarely been studied. Methods We harmonized and pooled baseline data from 11 population-based cohorts from 11 countries over 3 continents, including 14,792 women aged 60 years or older. We investigated the association between parity and the risk of dementia using logistic regression models that adjusted for age, educational level, hypertension, diabetes mellitus, and cohort, with additional analyses by region and dementia subtype. Results Across all cohorts, grand multiparous (5 or more childbirths) women had a 47% greater risk of dementia than primiparous (1 childbirth) women (odds ratio [OR] = 1.47, 95% confidence interval [CI] = 1.10–1.94), while nulliparous (no childbirth) women and women with 2 to 4 childbirths showed a comparable dementia risk to primiparous women. However, there were differences associated with region and dementia subtype. Compared to women with 1 to 4 childbirths, grand multiparous women showed a higher risk of dementia in Europe (OR = 2.99, 95% CI = 1.38–6.47) and Latin America (OR = 1.49, 95% CI = 1.04–2.12), while nulliparous women showed a higher dementia risk in Asia (OR = 2.15, 95% CI = 1.33–3.47). Grand multiparity was associated with 6.9-fold higher risk of vascular dementia in Europe (OR = 6.86, 95% CI = 1.81–26.08), whereas nulliparity was associated with a higher risk of Alzheimer disease (OR = 1.91, 95% CI 1.07–3.39) and non-Alzheimer non-vascular dementia (OR = 3.47, 95% CI = 1.44–8.35) in Asia. Conclusion Parity is associated with women’s risk of dementia, though this is not uniform across regions and dementia subtypes.
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    Estimating prevalence of subjective cognitive decline in and across international cohort studies of aging: a COSMIC study
    (BioMed Central Ltd, 2020-12-18) Röhr S; Pabst A; Riedel-Heller SG; Jessen F; Turana Y; Handajani YS; Brayne C; Matthews FE; Stephan BCM; Lipton RB; Katz MJ; Wang C; Guerchet M; Preux P-M; Mbelesso P; Ritchie K; Ancelin M-L; Carrière I; Guaita A; Davin A; Vaccaro R; Kim KW; Han JW; Suh SW; Shahar S; Din NC; Vanoh D; van Boxtel M; Köhler S; Ganguli M; Jacobsen EP; Snitz BE; Anstey KJ; Cherbuin N; Kumagai S; Chen S; Narazaki K; Ng TP; Gao Q; Gwee X; Brodaty H; Kochan NA; Trollor J; Lobo A; López-Antón R; Santabárbara J; Crawford JD; Lipnicki DM; Sachdev PS; for Cohort Studies of Memory in an International Consortium (COSMIC)
    Background Subjective cognitive decline (SCD) is recognized as a risk stage for Alzheimer’s disease (AD) and other dementias, but its prevalence is not well known. We aimed to use uniform criteria to better estimate SCD prevalence across international cohorts. Methods We combined individual participant data for 16 cohorts from 15 countries (members of the COSMIC consortium) and used qualitative and quantitative (Item Response Theory/IRT) harmonization techniques to estimate SCD prevalence. Results The sample comprised 39,387 cognitively unimpaired individuals above age 60. The prevalence of SCD across studies was around one quarter with both qualitative harmonization/QH (23.8%, 95%CI = 23.3–24.4%) and IRT (25.6%, 95%CI = 25.1–26.1%); however, prevalence estimates varied largely between studies (QH 6.1%, 95%CI = 5.1–7.0%, to 52.7%, 95%CI = 47.4–58.0%; IRT: 7.8%, 95%CI = 6.8–8.9%, to 52.7%, 95%CI = 47.4–58.0%). Across studies, SCD prevalence was higher in men than women, in lower levels of education, in Asian and Black African people compared to White people, in lower- and middle-income countries compared to high-income countries, and in studies conducted in later decades. Conclusions SCD is frequent in old age. Having a quarter of older individuals with SCD warrants further investigation of its significance, as a risk stage for AD and other dementias, and of ways to help individuals with SCD who seek medical advice. Moreover, a standardized instrument to measure SCD is needed to overcome the measurement variability currently dominant in the field.
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    Estimating prevalence of subjective cognitive decline in and across international cohort studies of aging: A COSMIC study
    (BioMed Central Ltd, 2020-05-26) Röhr S; Pabst A; Riedel-Heller SG; Jessen F; Turana Y; Handajani YS; Brayne C; Matthews FE; Stephan BCM; Lipton RB; Katz MJ; Wang C; Guerchet M; Preux P-M; Mbelesso P; Ritchie K; Ancelin M-L; Carrière I; Guaita A; Davin A; Vaccaro R; Kim KW; Han JW; Suh SW; Shahar S; Din NC; Vanoh D; van Boxtel M; Köhler S; Ganguli M; Jacobsen EP; Snitz BE; Anstey KJ; Cherbuin N; Kumagai S; Chen S; Narazaki K; Ng TP; Gao Q; Gwee X; Brodaty H; Kochan NA; Trollor J; Lobo A; López-Antón R; Santabárbara J; Crawford JD; Lipnicki DM; Sachdev PS; for Cohort Studies of Memory in an International Consortium (COSMIC)
    Background Subjective cognitive decline (SCD) is recognized as a risk stage for Alzheimer’s disease (AD) and other dementias, but its prevalence is not well known. We aimed to use uniform criteria to better estimate SCD prevalence across international cohorts. Methods We combined individual participant data for 16 cohorts from 15 countries (members of the COSMIC consortium) and used qualitative and quantitative (Item Response Theory/IRT) harmonization techniques to estimate SCD prevalence. Results The sample comprised 39,387 cognitively unimpaired individuals above age 60. The prevalence of SCD across studies was around one quarter with both qualitative harmonization/QH (23.8%, 95%CI = 23.3–24.4%) and IRT (25.6%, 95%CI = 25.1–26.1%); however, prevalence estimates varied largely between studies (QH 6.1%, 95%CI = 5.1–7.0%, to 52.7%, 95%CI = 47.4–58.0%; IRT: 7.8%, 95%CI = 6.8–8.9%, to 52.7%, 95%CI = 47.4–58.0%). Across studies, SCD prevalence was higher in men than women, in lower levels of education, in Asian and Black African people compared to White people, in lower- and middle-income countries compared to high-income countries, and in studies conducted in later decades. Conclusions SCD is frequent in old age. Having a quarter of older individuals with SCD warrants further investigation of its significance, as a risk stage for AD and other dementias, and of ways to help individuals with SCD who seek medical advice. Moreover, a standardized instrument to measure SCD is needed to overcome the measurement variability currently dominant in the field.
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    Lifestyle and incident dementia: A COSMIC individual participant data meta-analysis
    (Wiley Periodicals LLC on behalf of Alzheimer's Association, 2024-06-16) Van Asbroeck S; Köhler S; van Boxtel MPJ; Lipnicki DM; Crawford JD; Castro-Costa E; Lima-Costa MF; Blay SL; Shifu X; Wang T; Yue L; Lipton RB; Katz MJ; Derby CA; Guerchet M; Preux P-M; Mbelesso P; Norton J; Ritchie K; Skoog I; Najar J; Sterner TR; Scarmeas N; Yannakoulia M; Dardiotis T; Rolandi E; Davin A; Rossi M; Gureje O; Ojagbemi A; Bello T; Kim KW; Han JW; Oh DJ; Trompet S; Gussekloo J; Riedel-Heller SG; Röhr S; Pabst A; Shahar S; Rivan NFM; Singh DKA; Jacobsen E; Ganguli M; Hughes T; Haan M; Aiello AE; Ding D; Zhao Q; Xiao Z; Narazaki K; Chen T; Chen S; Ng TP; Gwee X; Gao Q; Brodaty H; Trollor J; Kochan N; Lobo A; Santabárbara J; Gracia-Garcia P; Sachdev PS; Deckers K; for Cohort Studies of Memory in an International Consortium (COSMIC)
    INTRODUCTION: The LIfestyle for BRAin Health (LIBRA) index yields a dementia risk score based on modifiable lifestyle factors and is validated in Western samples. We investigated whether the association between LIBRA scores and incident dementia is moderated by geographical location or sociodemographic characteristics. METHODS: We combined data from 21 prospective cohorts across six continents (N = 31,680) and conducted cohort-specific Cox proportional hazard regression analyses in a two-step individual participant data meta-analysis. RESULTS: A one-standard-deviation increase in LIBRA score was associated with a 21% higher risk for dementia. The association was stronger for Asian cohorts compared to European cohorts, and for individuals aged ≤75 years (vs older), though only within the first 5 years of follow-up. No interactions with sex, education, or socioeconomic position were observed. DISCUSSION: Modifiable risk and protective factors appear relevant for dementia risk reduction across diverse geographical and sociodemographic groups. HIGHLIGHTS: - A two-step individual participant data meta-analysis was conducted. - This was done at a global scale using data from 21 ethno-regionally diverse cohorts. - The association between a modifiable dementia risk score and dementia was examined. - The association was modified by geographical region and age at baseline. - Yet, modifiable dementia risk and protective factors appear relevant in all investigated groups and regions.
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    Parity and the risk of incident dementia: a COSMIC study
    (Cambridge University Press, 2020-10-20) Bae JB; Lipnicki DM; Han JW; Sachdev PS; Kim TH; Kwak KP; Kim BJ; Kim SG; Kim JL; Moon SW; Park JH; Ryu S-H; Youn JC; Lee DY; Lee DW; Lee SB; Lee JJ; Jhoo JH; Skoog I; Najar J; Sterner TR; Scarmeas N; Yannakoulia M; Dardiotis E; Riedel-Heller S; Roehr S; Pabst A; Ding D; Zhao Q; Liang X; Lobo A; De-la-Cámara C; Lobo E; Kim KW; for Cohort Studies of Memory in an International Consortium (COSMIC)
    Aims To investigate the association between parity and the risk of incident dementia in women. Methods We pooled baseline and follow-up data for community-dwelling women aged 60 or older from six population-based, prospective cohort studies from four European and two Asian countries. We investigated the association between parity and incident dementia using Cox proportional hazards regression models adjusted for age, educational level, hypertension, diabetes mellitus and cohort, with additional analysis by dementia subtype (Alzheimer dementia (AD) and non-Alzheimer dementia (NAD)). Results Of 9756 women dementia-free at baseline, 7010 completed one or more follow-up assessments. The mean follow-up duration was 5.4 ± 3.1 years and dementia developed in 550 participants. The number of parities was associated with the risk of incident dementia (hazard ratio (HR) = 1.07, 95% confidence interval (CI) = 1.02–1.13). Grand multiparity (five or more parities) increased the risk of dementia by 30% compared to 1–4 parities (HR = 1.30, 95% CI = 1.02–1.67). The risk of NAD increased by 12% for every parity (HR = 1.12, 95% CI = 1.02–1.23) and by 60% for grand multiparity (HR = 1.60, 95% CI = 1.00–2.55), but the risk of AD was not significantly associated with parity. Conclusions Grand multiparity is a significant risk factor for dementia in women. This may have particularly important implications for women in low and middle-income countries where the fertility rate and prevalence of grand multiparity are high.
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    Sex differences in dementia risk and risk factors: Individual-participant data analysis using 21 cohorts across six continents from the COSMIC consortium.
    (John Wiley and Sons, Inc., 2023-08-01) Gong J; Harris K; Lipnicki DM; Castro-Costa E; Lima-Costa MF; Diniz BS; Xiao S; Lipton RB; Katz MJ; Wang C; Preux P-M; Guerchet M; Gbessemehlan A; Ritchie K; Ancelin M-L; Skoog I; Najar J; Sterner TR; Scarmeas N; Yannakoulia M; Kosmidis MH; Guaita A; Rolandi E; Davin A; Gureje O; Trompet S; Gussekloo J; Riedel-Heller S; Pabst A; Röhr S; Shahar S; Singh DKA; Rivan NFM; Boxtel MV; Köhler S; Ganguli M; Chang C-C; Jacobsen E; Haan M; Ding D; Zhao Q; Narazaki K; Chen T; Chen S; Ng TP; Gwee X; Numbers K; Mather KA; Scazufca M; Lobo A; De-la-Cámara C; Lobo E; Sachdev PS; Brodaty H; Hackett ML; Peters SAE; Woodward M
    INTRODUCTION: Sex differences in dementia risk, and risk factor (RF) associations with dementia, remain uncertain across diverse ethno-regional groups. METHODS: A total of 29,850 participants (58% women) from 21 cohorts across six continents were included in an individual participant data meta-analysis. Sex-specific hazard ratios (HRs), and women-to-men ratio of hazard ratios (RHRs) for associations between RFs and all-cause dementia were derived from mixed-effect Cox models. RESULTS: Incident dementia occurred in 2089 (66% women) participants over 4.6 years (median). Women had higher dementia risk (HR, 1.12 [1.02, 1.23]) than men, particularly in low- and lower-middle-income economies. Associations between longer education and former alcohol use with dementia risk (RHR, 1.01 [1.00, 1.03] per year, and 0.55 [0.38, 0.79], respectively) were stronger for men than women; otherwise, there were no discernible sex differences in other RFs. DISCUSSION: Dementia risk was higher in women than men, with possible variations by country-level income settings, but most RFs appear to work similarly in women and men.
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    Social connections and risk of incident mild cognitive impairment, dementia, and mortality in 13 longitudinal cohort studies of ageing.
    (Wiley Periodicals LLC on behalf of Alzheimer’s Association., 2023-11) Mahalingam G; Samtani S; Lam BCP; Lipnicki DM; Lima-Costa MF; Blay SL; Castro-Costa E; Shifu X; Guerchet M; Preux P-M; Gbessemehlan A; Skoog I; Najar J; Sterner TR; Scarmeas N; Yannakoulia M; Dardiotis T; Kim K-W; Riedel-Heller S; Röhr S; Pabst A; Shahar S; Numbers K; Ganguli M; Hughes TF; Chang C-CH; Crowe M; Ng TP; Gwee X; Chua DQL; Rymaszewska J; Wolf-Ostermann K; Welmer A-K; Stafford J; Mélis R; Vernooij-Dassen M; Jeon Y-H; Sachdev PS; Brodaty H; SHARED consortium for the Cohort Studies of Memory in an International Consortium (COSMIC)
    INTRODUCTION: 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. METHODS: 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. RESULTS: 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. DISCUSSION: Different aspects of social connections - structure, function, and quality - are associated with benefits for healthy aging internationally. HIGHLIGHTS: 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. Highlights 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.
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    Subjective cognitive decline and rates of incident Alzheimer's disease and non–Alzheimer's disease dementia.
    (John Wiley and Sons Inc on behalf of The Alzheimer's Association, 2019-03) Slot RER; Sikkes SAM; Berkhof J; Brodaty H; Buckley R; Cavedo E; Dardiotis E; Guillo-Benarous F; Hampel H; Kochan NA; Lista S; Luck T; Maruff P; Molinuevo JL; Kornhuber J; Reisberg B; Riedel-Heller SG; Risacher SL; Roehr S; Sachdev PS; Scarmeas N; Scheltens P; Shulman MB; Saykin AJ; Verfaillie SCJ; Visser PJ; Vos SJB; Wagner M; Wolfsgruber S; Jessen F; Alzheimer's Disease Neuroimaging Initiative; DESCRIPA working group; INSIGHT-preAD study group; SCD-I working group; van der Flier WM
    Introduction In this multicenter study on subjective cognitive decline (SCD) in community-based and memory clinic settings, we assessed the (1) incidence of Alzheimer's disease (AD) and non-AD dementia and (2) determinants of progression to dementia. Methods Eleven cohorts provided 2978 participants with SCD and 1391 controls. We estimated dementia incidence and identified risk factors using Cox proportional hazards models. Results In SCD, incidence of dementia was 17.7 (95% Poisson confidence interval 15.2-20.3)/1000 person-years (AD: 11.5 [9.6-13.7], non-AD: 6.1 [4.7-7.7]), compared with 14.2 (11.3-17.6) in controls (AD: 10.1 [7.7-13.0], non-AD: 4.1 [2.6-6.0]). The risk of dementia was strongly increased in SCD in a memory clinic setting but less so in a community-based setting. In addition, higher age (hazard ratio 1.1 [95% confidence interval 1.1-1.1]), lower Mini–Mental State Examination (0.7 [0.66-0.8]), and apolipoprotein E ε4 (1.8 [1.3-2.5]) increased the risk of dementia. Discussion SCD can precede both AD and non-AD dementia. Despite their younger age, individuals with SCD in a memory clinic setting have a higher risk of dementia than those in community-based cohorts.
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    Trajectory of Cognitive Decline Before and After Stroke in 14 Population Cohorts
    (American Medical Association, 2024-10-02) Lo JW; Crawford JD; Lipnicki DM; Lipton RB; Katz MJ; Preux P-M; Guerchet M; d'Orsi E; Quialheiro A; Rech CR; Ritchie K; Skoog I; Najar J; Sterner TR; Rolandi E; Davin A; Rossi M; Riedel-Heller SG; Pabst A; Röhr S; Ganguli M; Jacobsen E; Snitz BE; Anstey KJ; Aiello AE; Brodaty H; Kochan NA; Chen Y-C; Chen J-H; Sanchez-Juan P; Del Ser T; Valentí M; Lobo A; De-la-Cámara C; Lobo E; Sachdev PS
    IMPORTANCE: Poststroke cognitive impairment is common, but the cognitive trajectory following a first stroke, relative to prestroke cognitive function, remains unclear. OBJECTIVE: To map the trajectory of cognitive function before any stroke and after stroke in global cognition and in 4 cognitive domains, as well as to compare the cognitive trajectory prestroke in stroke survivors with the trajectory of individuals without incident stroke over follow-up. DESIGN, SETTING, AND PARTICIPANTS: The study used harmonized and pooled data from 14 population-based cohort studies included in the Cohort Studies of Memory in an International Consortium collaboration. These studies were conducted from 1993 to 2019 across 11 countries among community-dwelling older adults without a history of stroke or dementia. For this study, linear mixed-effects models were used to estimate trajectories of cognitive function poststroke relative to a stroke-free cognitive trajectory. The full model adjusted for demographic and vascular risk factors. Data were analyzed from July 2022 to March 2024. EXPOSURE: Incident stroke. MAIN OUTCOMES AND MEASURES: The primary outcome was global cognition, defined as the standardized average of 4 cognitive domains (language, memory, processing speed, and executive function). Cognitive domain scores were formed by selecting the most commonly administered test within each domain and standardizing the scores. RESULTS: The study included 20 860 participants (12 261 [58.8%] female) with a mean (SD) age of 72.9 (8.0) years and follow-up of 7.51 (4.2) years. Incident stroke was associated with a substantial acute decline in global cognition (-0.25 SD; 95% CI, -0.33 to -0.17 SD), the Mini-Mental State Examination, and all cognitive domains (ranging from -0.17 SD to -0.22 SD), as well as accelerated decline in global cognition (-0.038 SD per year; 95% CI, -0.057 to -0.019 SD per year) and all domains except memory (ranging from -0.020 to -0.055 SD per year), relative to a stroke-free cognitive trajectory. There was no significant difference in prestroke slope in stroke survivors compared with the rate of decline in individuals without stroke in all cognitive measures. The mean rate of decline without a previous stroke was -0.049 SD per year (95% CI, -0.051 to -0.047 SD) in global cognition. CONCLUSIONS AND RELEVANCE: In this cohort study using pooled data from 14 cohorts, incident stroke was associated with acute and accelerated long-term cognitive decline in older stroke survivors.