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Cited by 87Dementia and Cognitive Impairment ResearchHealth disparities and outcomesAcute Ischemic Stroke Management

Associations between social relationship measures, serum brain-derived neurotrophic factor, and risk of stroke and dementia

Open access
Salinas, Joel, Beiser, Alexa, Himali, Jayandra J., Satizabal, Claudia L., Aparicio, Hugo J., Weinstein, Galit, Mateen, Farrah J., Berkman, Lisa F. +2 more·2017·Alzheimer's & Dementia: Translational Research & Clinical Interventions
DOI 10.1016/j.trci.2017.03.001PMC PMC5651441
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Abstract

Introduction: Mechanisms underlying social determinants of stroke and dementia are unclear and brain‐derived neurotrophic factor (BDNF) may contribute as a molecular link. Methods: Using the Framingham Study, we examined social relationship measures as predictors of higher serum BDNF level and cumulative incidence of stroke and dementia. Results: Among 3294 participants, controlling for age and sex, isolation trended with lower BDNF (odds ratio = 0.69 [0.47–1.00]). Participants with more companionship had reduced risk for stroke (hazard ratio [HR] = 0.59 [0.41–0.83]) and dementia (HR = 0.67 [0.49–0.92]). Greater emotional support was associated with higher BDNF (odds ratio = 1.27 [1.04–1.54]), reduced dementia risk (HR = 0.69 [0.51–0.94], and among smokers, reduced stroke risk (HR = 0.23 [0.10–0.57]). Associations persisted after additional adjustments. BDNF partly mediated the total effect between emotional support and dementia risk. Conclusions: Availability of social support appears to be associated with increased BDNF levels and, in certain subsets, reduce risk of subsequent dementia and stroke, thus warranting study of these pathways to understand their role in neuroprotection.

AI snapshot

Written from the paper’s full text.

TL;DR

In the Framingham Study, social isolation trended with lower serum BDNF, while emotional support was associated with higher serum BDNF and lower dementia risk; having someone available to listen was associated with lower stroke and dementia risk. BDNF appeared to mediate only a small portion of the emotional-support–dementia association.

Key findings

  • Among 3294 participants, social isolation trended with lower odds of above-median serum BDNF (OR = 0.69, 95% CI 0.47–1.00; P = .052), and emotional support was associated with higher BDNF (OR = 1.27, 95% CI 1.04–1.54; P = .021).
  • During median 11-year follow-up, having someone available to listen most/all of the time was associated with reduced incident stroke (HR = 0.59, 95% CI 0.41–0.83; P = .003) and dementia (HR = 0.67, 95% CI 0.49–0.92; P = .012).
  • Emotional support was associated with reduced dementia risk (HR = 0.69, 95% CI 0.51–0.94; P = .018), and among smokers it was associated with reduced stroke risk (HR = 0.23, 95% CI 0.10–0.57; P < .001).
  • Causal mediation analysis suggested about 1.6% of the total effect between emotional support and dementia risk was mediated through increased serum BDNF.

Methods

  • Prospective community-based cohort using Framingham Heart Study Original and Offspring participants; 3294 had social relationship and serum BDNF data, 1834 were analyzed for dementia, and 3210 for stroke, with median 11 years of follow-up.
  • Social relationships were measured with the Berkman-Syme Social Network Index, including social isolation/connectedness and support dimensions (listening, advice, affection, emotional support); serum BDNF was assayed by ELISA.
  • Multivariable logistic regression modeled BDNF above versus below median; Cox proportional hazards models examined incident dementia and stroke, with sequential adjustment for age/sex, baseline BDNF, and additional covariates; smoking interactions and mediation analyses were also performed.

Limitations

  • Stated: observational design cannot establish causality; residual confounding and reverse causality/homophily or propinquity may bias results; serum BDNF may not fully reflect brain BDNF, and plasma, pro-BDNF, or postmortem BDNF might show stronger effects; findings are hypothesis generating and need replication, including in other race/ethnic groups.
  • Stated: some stratified categories were small, and the sample was largely of European ancestry.
  • Evident from the text: social isolation was uncommon (116/3294, 4%), and no adjustment for multiple comparisons was made, which the authors note was intentional for hypothesis generation.

Model-written summary. Check it against the paper before relying on it.

Integrity signals

Registry

Crossref · 10.1016/j.trci.2017.03.001

Cites

Statistics

Nothing to recompute.

Claims the paper makes

0 of 37 cited sources checked · 0 supported · 0 flagged

  • Findingown data

    Having someone available to listen was associated with decreased risk of stroke in interaction with smoking status (HR, 0.21; 95% CI, 0.09-0.53; P < .001).

    “listen (HR, 0.21; 95% CI, 0.09–0.53; P < .001)”
    Quote in the paperSubstantial claim
  • Findingown data

    During a median 11 years of follow-up, 183 of 3210 (6%) participants had incident stroke.

    “During a median 11 years of follow-up, 243 of 1834 (13%) participants developed incident dementia and 183 of 3210 (6%) had incident stroke.”
    Quote in the paperNot a substantial claim
  • Findingown data

    During a median 11 years of follow-up, 243 of 1834 (13%) participants developed incident dementia.

    “During a median 11 years of follow-up, 243 of 1834 (13%) participants developed incident dementia and 183 of 3210 (6%) had incident stroke.”
    Quote in the paperNot a substantial claim
  • Findingown data

    Having someone provide emotional support most or all of the time was associated with reduced risk of dementia (HR, 0.69; 95% CI, 0.51-0.94; P = .018).

    “Having someone provide emotional support most or all of the time was associated with reduced risk of dementia (HR, 0.69; 95% CI, 0.51–0.94; P = .018) (Table 3).”
    Quote in the paperSubstantial claim
  • Findingown data

    In causal mediation analysis, about 1.6% of the total effect between emotional support and dementia risk is mediated through an increase in serum BDNF.

    “in causal mediation analysis, the size of the indirect effect suggests that about 1.6% of the total effect (standardized β = 0.69; 95% CI, 0.51–0.94; P = .017) between emotional support and dementia risk is mediated through an increase in serum BDNF.”
    Quote in the paperNot a substantial claim
  • May combine two claims. 14
  • Classified as probably not a substantial claim. 21
  • The quote only partly states this claim. 1

  • May combine two claims.

    Findingown data

    Social connectedness was unassociated with incident stroke or dementia.

    “Social isolation and social connectedness were unassociated with incident stroke or dementia (Table 3).”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Findingown data

    Sensitivity analysis excluding participants with mild cognitive impairment revealed minimal change in β estimates for Cox proportional hazards models.

    “Sensitivity analysis performed by excluding participants with mild cognitive impairment revealed minimal change in β estimates for Cox proportional hazards models.”
    Quote in the paperNot a substantial claim

  • The quote only partly states this claim.

    Findingown data

    Having someone available to give advice was associated with decreased risk of stroke in interaction with smoking status (HR, 0.39; 95% CI, 0.16-0.95; P = .037).

    “we found significant associations between decreased risk of stroke and having someone available to give advice (HR, 0.39; 95% CI, 0.16–0.95; P = .037)”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    Social isolation was unassociated with incident stroke or dementia.

    “Social isolation and social connectedness were unassociated with incident stroke or dementia (Table 3).”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Premisecitation

    Small social networks have been associated with higher risk of incident stroke, cognitive dysfunction, and accumulation of Alzheimer's disease pathology.

    “Because lower circulating BDNF levels and small social networks have separately been associated with higher risk of incident stroke [3], [4], cognitive dysfunction [2], [5], [6], and the accumulation of Alzheimer's disease pathology [7], [8]”
    Quote in the paperSubstantial claim0 of 3 sources checked
    • cites [3] Valtorta N.K. Kanaan M. Gilbody S. Ronzi S. Hanratty B. Loneliness and social isolation as risk factors for coronary heart disease and stroke: systematic review and meta-analysis of longitudinal observational studies Heart 102 2016 1009 1016 27091846 PMC4941172 source

      Not checked in the free run.

    • cites [4] Pikula A. Beiser A.S. Chen T.C. Preis S.R. Vorgias D. DeCarli C. Serum brain-derived neurotrophic factor and vascular endothelial growth factor levels are associated with risk of stroke and vascular brain injury: Framingham Study Stroke 44 2013 2768 2775 23929745 PMC3873715 source

      Not checked in the free run.

    • cites [7] Bennett D.A. Schneider J.A. Tang Y. Arnold S.E. Wilson R.S. The effect of social networks on the relation between Alzheimer's disease pathology and level of cognitive function in old people: a longitudinal cohort study Lancet Neurol 5 2006 406 412 16632311 source

      Not checked in the free run.

  • Classified as probably not a substantial claim.

    Study design and conductreasoning

    Sensitivity analysis excluded participants with prevalent mild cognitive impairment to address reverse causality.

    “To address the possibility of reverse causality from mild cognitive impairment affecting social relationships before diagnosis of dementia, sensitivity analysis was performed by excluding participants with prevalent mild cognitive impairment [34].”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [34] Jefferson A.L. Beiser A.S. Himali J.J. Seshadri S. O'Donnell C.J. Manning W.J. Low cardiac index is associated with incident dementia and Alzheimer disease: the Framingham Heart Study Circulation 131 2015 1333 1339 25700178 PMC4398627 source

      Not checked in the free run.

  • Classified as probably not a substantial claim.

    Premisecitation

    Little is known about the neurobiological mechanisms underlying the association of social relationships and healthy cognitive aging.

    “However, little is known about the neurobiological mechanisms underlying the association of social relationships and healthy cognitive aging [2], [3].”
    Quote in the paperSubstantial claim0 of 2 sources checked
    • cites [2] Kuiper J.S. Zuidersma M. Oude Voshaar R.C. Zuidema S.U. van den Heuvel E.R. Stolk R.P. Social relationships and risk of dementia: a systematic review and meta-analysis of longitudinal cohort studies Ageing Res Rev 22 2015 39 57 25956016 source

      Not checked in the free run.

    • cites [3] Valtorta N.K. Kanaan M. Gilbody S. Ronzi S. Hanratty B. Loneliness and social isolation as risk factors for coronary heart disease and stroke: systematic review and meta-analysis of longitudinal observational studies Heart 102 2016 1009 1016 27091846 PMC4941172 source

      Not checked in the free run.

  • Classified as probably not a substantial claim.

    Study design and conductcitation

    Dementia was diagnosed according to DSM-IV criteria.

    “Dementia was diagnosed according to the criteria of the Diagnostic and Statistical Manual of Mental Disorders (Fourth Edition) [24].”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [24] American Psychiatric Association, American Psychiatric Association Task Force on DSM-IV Diagnostic and Statistical Manual of Mental Disorders: DSM-IV 4th ed. 1994 American Psychiatric Association Washington, DC

      Not checked in the free run.

  • Classified as probably not a substantial claim. May combine two claims.

    Study design and conductown data

    Primary analyses were first adjusted for age and sex, then additionally adjusted for baseline BDNF levels.

    “All primary analyses were first adjusted for age and sex. We then additionally adjusted for baseline BDNF levels (model B) to see if this partially attenuated and thus contributed the association observed.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Premisecitation

    The Berkman-Syme Social Network Index measures both social network size and degree of social support and predicts mortality independent of age, self-reported physical health and socioeconomic status, lifestyle, and use of preventive health services.

    “The self-reported Berkman-Syme Social Network Index (SNI) measures both social network size and the degree of social support provided to the individual and predicts mortality independent of age, self-reported physical health and socioeconomic status, lifestyle (i.e., smoking, alcohol, obesity, and physical activity), and use of preventive health services [1], [19].”
    Quote in the paperSubstantial claim0 of 2 sources checked
    • cites [1] Berkman L.F. Glass T. Brissette I. Seeman T.E. From social integration to health: Durkheim in the new millennium Soc Sci Med 51 2000 843 857 10972429 source

      Not checked in the free run.

    • cites [19] Berkman L.F. Syme S.L. Social networks, host resistance, and mortality: a nine-year follow-up study of Alameda County residents Am J Epidemiol 109 1979 186 204 425958 source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Social relationships are strongly linked with physical and mental health.

    “Social environments, particularly social relationships, are strongly linked with physical and mental health [1].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [1] Berkman L.F. Glass T. Brissette I. Seeman T.E. From social integration to health: Durkheim in the new millennium Soc Sci Med 51 2000 843 857 10972429 source

      Not checked in the free run.

  • Classified as probably not a substantial claim.

    Study design and conductreasoning

    Analyses were adjusted for a priori covariates including age, sex, education, physical activity, smoking status, and components of the Framingham Stroke Risk Profile.

    “Because factors such as age, sex, education, physical activity, and smoking status may determine social relationships and also influence BDNF levels, dementia risk, and stroke risk, we parsimoniously adjusted for a priori variables [4], [25], [26].”
    Quote in the paperSubstantial claim0 of 3 sources checked
    • cites [4] Pikula A. Beiser A.S. Chen T.C. Preis S.R. Vorgias D. DeCarli C. Serum brain-derived neurotrophic factor and vascular endothelial growth factor levels are associated with risk of stroke and vascular brain injury: Framingham Study Stroke 44 2013 2768 2775 23929745 PMC3873715 source

      Not checked in the free run.

    • cites [25] Andel R. Vigen C. Mack W.J. Clark L.J. Gatz M. The effect of education and occupational complexity on rate of cognitive decline in Alzheimer's patients J Int Neuropsychol Soc 12 2006 147 152 16433954 source

      Not checked in the free run.

    • cites [26] Bus B.A. Molendijk M.L. Penninx B.J. Buitelaar J.K. Kenis G. Prickaerts J. Determinants of serum brain-derived neurotrophic factor Psychoneuroendocrinology 36 2011 228 239 20702043 source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Study design and conductcitation

    The SNI has published psychometrics and evidence of predictive validity.

    “Psychometrics on the SNI and additional evidence for the scale's predictive validity are available in previous publications [19], [20].”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites [19] Berkman L.F. Syme S.L. Social networks, host resistance, and mortality: a nine-year follow-up study of Alameda County residents Am J Epidemiol 109 1979 186 204 425958 source

      Not checked in the free run.

    • cites [20] Loucks E.B. Sullivan L.M. D'Agostino R.B. Sr. Larson M.G. Berkman L.F. Benjamin E.J. Social networks and inflammatory markers in the Framingham Heart Study J Biosoc Sci 38 2006 835 842 16441967 source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Study design and conductown data

    Serum BDNF assays had intra-assay and interassay coefficients of variation of 4.8% and 7.6%, respectively.

    “The intra-assay and interassay coefficients of variation were 4.8% and 7.6%, respectively.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Premisecitation

    Lower circulating BDNF levels have been associated with higher risk of incident stroke, cognitive dysfunction, and accumulation of Alzheimer's disease pathology.

    “Because lower circulating BDNF levels and small social networks have separately been associated with higher risk of incident stroke [3], [4], cognitive dysfunction [2], [5], [6], and the accumulation of Alzheimer's disease pathology [7], [8]”
    Quote in the paperSubstantial claim0 of 3 sources checked
    • cites [3] Valtorta N.K. Kanaan M. Gilbody S. Ronzi S. Hanratty B. Loneliness and social isolation as risk factors for coronary heart disease and stroke: systematic review and meta-analysis of longitudinal observational studies Heart 102 2016 1009 1016 27091846 PMC4941172 source

      Not checked in the free run.

    • cites [4] Pikula A. Beiser A.S. Chen T.C. Preis S.R. Vorgias D. DeCarli C. Serum brain-derived neurotrophic factor and vascular endothelial growth factor levels are associated with risk of stroke and vascular brain injury: Framingham Study Stroke 44 2013 2768 2775 23929745 PMC3873715 source

      Not checked in the free run.

    • cites [7] Bennett D.A. Schneider J.A. Tang Y. Arnold S.E. Wilson R.S. The effect of social networks on the relation between Alzheimer's disease pathology and level of cognitive function in old people: a longitudinal cohort study Lancet Neurol 5 2006 406 412 16632311 source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductcitation

    Results are reported in accordance with STROBE guidelines.

    “Results are reported in accordance with STROBE guidelines [17].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [17] von Elm E. Altman D.G. Egger M. Pocock S.J. Gøtzsche P.C. Vandenbroucke J.P. Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) statement: guidelines for reporting observational studies Ann Intern Med 147 2007 573 577 17938396 source

      Not checked in the free run.

  • Classified as probably not a substantial claim.

    Study design and conductreasoning

    Statistical significance was set at two-sided α ≤ 0.05 without adjusting for multiple comparisons given the study's aim for hypothesis generation.

    “Statistical significance for regressions was set at a two-sided α ≤ 0.05 without adjusting for multiple comparisons given the study's aim for hypothesis generation in which results would need to be validated in additional studies.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductreasoning

    Our results may also reflect residual reverse causality bias from homophily or propinquity.

    “Our results may also reflect some residual reverse causality bias from homophily or propinquity”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S2 (checkable), S3 (load-bearing).

    Study design and conductreasoning

    Other unknown factors may have biased the results despite adjustment for multiple potential confounders.

    “Although adjustment was possible for multiple potential confounders, other unknown factors may have biased results.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Interpretationown data

    Emotional support and having someone available to listen are forms of social support that may independently help reduce the risk of stroke and dementia.

    “Emotional support and, in particular, having someone available to listen are forms of social support that may independently help reduce the risk of stroke and dementia.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S2 (checkable), S3 (load-bearing). May combine two claims.

    Interpretationcitation

    Our findings might extend observed effects of BDNF and lifestyle factors on human studies as well as on animal models associating BDNF with social enrichment.

    “Our findings might extend observed effects of BDNF and lifestyle factors on human studies [38] as well as on animal models associating BDNF with the broader construct of social enrichment [12].”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites [38] Weinstein G. Preis S.R. Beiser A.S. Kaess B. Chen T.C. Satizabal C. Clinical and environmental correlates of serum BDNF: a descriptive study with plausible implications for AD research Curr Alzheimer Res 2017 [Epub ahead of print] PMC6026027 28164772 source

      Not checked in the free run.

    • cites [12] Branchi I. D'Andrea I. Fiore M. Di Fausto V. Aloe L. Alleva E. Early social enrichment shapes social behavior and nerve growth factor and brain-derived neurotrophic factor levels in the adult mouse brain Biol Psychiatry 60 2006 690 696 16533499 source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based).

    Interpretationnone given

    This is also the first study using the Framingham Study to investigate links between social relationships and risk for stroke and dementia.

    “This is also the first study using the Framingham Study to investigate links between social relationships and risk for stroke and dementia.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Study design and conductnone given

    The study had continuous, rigorous surveillance for clinical end points with minimal loss to follow-up.

    “continuous, rigorous surveillance for clinical end points with minimal loss to follow-up.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Interpretationcitation

    The findings are consistent with similar results in animal models.

    “our findings are consistent with similar results in animal models [12].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [12] Branchi I. D'Andrea I. Fiore M. Di Fausto V. Aloe L. Alleva E. Early social enrichment shapes social behavior and nerve growth factor and brain-derived neurotrophic factor levels in the adult mouse brain Biol Psychiatry 60 2006 690 696 16533499 source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S2 (checkable). May combine two claims.

    Interpretationreasoning

    Cognitive impairment can affect social relationships, so social determinants need to be ascertained years before onset of age-related neurologic disease.

    “given that cognitive impairment can affect social relationships, social determinants would need to be ascertained years before the onset of age-related neurologic disease.”
    Quote in the paperNot a substantial claim

  • Classified as probably not a substantial claim.

    Premisecitation

    Previous studies have found that specific types of social isolation were associated with increased dementia risk.

    “previous studies have found that specific types of social isolation were associated with increased dementia risk [36], [37].”
    Quote in the paperSubstantial claim0 of 2 sources checked
    • cites [36] Bickel H. Cooper B. Incidence and relative risk of dementia in an urban elderly population: findings of a prospective field study Psychol Med 24 1994 179 192 8208883 source

      Not checked in the free run.

    • cites [37] Fratiglioni L. Wang H.X. Ericsson K. Maytan M. Winblad B. Influence of social network on occurrence of dementia: a community-based longitudinal study Lancet 355 2000 1315 1319 10776744 source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S2 (checkable), S3 (load-bearing), S4 (based).

    Interpretationnone given

    The effect size of associations with BDNF in the brain may have been more pronounced if plasma BDNF, pro-BDNF, or postmortem BDNF levels had been used.

    “the effect size of associations with BDNF in the brain may have been more pronounced if plasma BDNF, pro-BDNF, or postmortem BDNF levels had been used.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Study design and conductown data

    The sample in some stratified categories was small and largely of European ancestry, so results need replication in other race and ethnic groups.

    “our sample in some of the stratified categories was small and largely of European ancestry so our results also need replication in other race and ethnic groups.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S2 (checkable).

    Interpretationreasoning

    A community-based prospective cohort is ideal to identify novel pathways involved in brain health because prospectively collected data are better able to distinguish temporal direction of associations.

    “a community-based prospective cohort is ideal to identify novel pathways that might be involved in brain health because studies of prospectively collected data are better able to distinguish the temporal direction of any observed association to help separate probable cause and effect.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Premisecitation

    Serum BDNF parallels relative difference in BDNF levels, but BDNF levels may be substantially higher, have attenuated effects over time, and may be subject to variability because of differences in expression levels of BDNF receptors.

    “Although serum BDNF parallels relative difference in BDNF levels, BDNF levels may be substantially higher, have attenuated effects over time, and may be subject to variability of effect because of differences in the expression levels of BDNF receptors [8].”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [8] Kao P.F. Banigan M.G. Vanderburg C.R. McKee A.C. Polgar P.R. Seshadri S. Increased expression of TrkB and Capzb2 accompanies preserved cognitive status in early Alzheimer disease pathology J Neuropathol Exp Neurol 71 2012 654 664 22710966 PMC3398703 source

      Not checked in the free run.

30 of 30

  • The paper relies on this without support.

    No clinical study to date has systematically examined the associations between social relationships and BDNF in humans as well as how these associations might influence risk for stroke and dementia.

    “To our knowledge, there has been no clinical study to date that has systematically examined the associations between social relationships and BDNF in humans as well as how these associations might influence the risk for stroke and dementia.”

  • The paper relies on this without support.

    Mechanisms underlying social determinants of stroke and dementia are unclear.

    “Mechanisms underlying social determinants of stroke and dementia are unclear and brain-derived neurotrophic factor (BDNF) may contribute as a molecular link.”
2 of 2

Claims other papers make about this one

Each is checked against this paper’s own text: does it say what the citing paper says it does?

Self-check

Percentages, sums and reported differences re-computed from the paper’s own numbers.

Each contradiction between two passages listed here was confirmed by an independent check.

  • Stroke analysis sample is listed as entirely having prevalent stroke

    Minor

    The methods say participants with prevalent stroke were excluded from the stroke analysis, but Table 1 reports prevalent stroke for all 3,210 participants in that sample.

1 of 1

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References 46 · Cited by 87

Research works printed but not linked: 1

  1. Cupples L., 1987, Some Risk Factors Related to the Annual Incidence of Cardiovascular Disease and Death Using Pooled Repeated Biennial Measurements: Framingham Heart Study, 30‐year Follow‐up

Authors
Salinas, J., Beiser, A., Himali, J. J., Satizabal, C. L., Aparicio, H. J., Weinstein, G., Mateen, F. J., Berkman, L. F., Rosand, J., & Seshadri, S.
Affiliations
  • Harvard University (US)
  • Boston University (US)
  • The Framingham Heart Study Boston MA USA
  • Framingham Heart Study (US)
Corresponding author
Salinas, Joel
ORCID
Venue
Alzheimer's & Dementia: Translational Research & Clinical Interventions
Publisher
Wiley
Published
2017-03-22
Volume
3
Issue
2
Pages
229-237
ISSN
2352-8737 (ISSN-L)
DOI
10.1016/j.trci.2017.03.001
PMC
PMC5651441
OpenAlex
W2601726226
Semantic Scholar
5b5feb88bde97b80557521e56bd358b418d8c181
Cited by
87
References
46
Citations by year
2026: 7 · 2025: 6 · 2024: 13 · 2023: 13 · 2022: 9 · 2021: 15 · 2020: 7 · 2019: 8 · 2018: 7 · 2017: 2
FWCI
5.39
Type
journal article
Language
en
Open access
Licence
Locations
  • Alzheimer s & Dementia Translational Research & Clinical Interventions (publishedVersion, cc-by-nc-nd)
  • PubMed Central (publishedVersion, cc-by-nc-nd)
  • PubMed (publishedVersion)
  • Digital Access to Scholarship at Harvard (DASH) (Harvard University) (submittedVersion, cc-by)
Funders
  • School of Medicine, Boston University
  • Massachusetts General Hospital
  • National Institute on Aging (AG031287)
Topics
  • Health Sciences › Medicine › Psychiatry and Mental health › Dementia and Cognitive Impairment Research
  • Social Sciences › Health › Health disparities and outcomes
  • Health Sciences › Medicine › Epidemiology › Acute Ischemic Stroke Management
Keywords
interpersonal relationships, social isolation, companionship, emotional support, brain-derived neurotrophic factor, serum BDNF, stroke risk, dementia risk, social determinants of health, mediation, smoking, neuroprotection

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