Table 1. Relationship of IQ to Risk for Dementia. Adolescent IQ = risk dementia For Childhood SES = risk for AD

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1 .7 The Clinicin s Guide To Lifetime Intellectul Stimultion And Activity As A Protection Aginst Dementi for Persons of Africn- Americn Heritge. Overview Intellect is n integrl prt of cognitive nd physicl helth. Persons with higher IQ pper to live longer nd demonstrte greter cpcity to comply with helth interventions. Intellectul function in older persons cn be determined by testing performed in erly life, estimtes bsed on cdemic/professionl chievement, or testing in lter life. Intellect is complex domin s mesured by cognitive, motoric nd socil skills. Specific dementis produce disproportionte levels of impirment in specific domins. For instnce, Alzheimer s disese dmges cognitive function while spring socil grces in the erly phse. Frontotemporl dementi produces the opposite pttern. Severl groups of dt hve exmined specific questions tht exmine the reltionship between pre-disese intellect nd risk for dementi including:. Wht is the reltionship between dolescent or dult IQ nd risk for dementi?. Wht is the reltionship between eduction or socioeconomic strt nd risk for dementi?. How does IQ or eduction impct brin imging mrkers for cognitive function?. How does IQ or eduction level interct with risk for dementi in persons with specific types of neuropthology?. Understnding The Reltionship Between Lifetime IQ And The Risk For Dementi Severl studies hve reviewed the reltionship between IQ in childhood dolescence nd the risk for developing dementi in lter life. Studies in the United Sttes nd Gret Britin hve exmined individuls who underwent intellectul ssessments in erly life (See Tble ). Most studies report n inverse reltionship between IQ nd risk for dementi where individuls in the lowest qurtile for intellect hd the gretest risk for developing dementi in lter life. Tble. Reltionship of IQ to Risk for Dementi 89 Comments Adolescent IQ = risk dementi For Childhood SES = risk for C C 9 Adolescent linguistic bility = risk for C IQ t ge = risk for t ge 77 C IQ in childhood = risk lte onset dementi C Youth IQ = lte risk for C Eduction The Reltionship Between Eductionl Achievement And Lte Life Risk For Dementi Acdemic chievement is not necessrily bounded by IQ. Some individuls with high IQ my never exceed with eduction while mny persons of norml intellect my persevere in cdemic endevors. Generl groupings include those individuls with less thn n 8 th grde eduction, high school grdutes, college grdutes nd persons with dvnced degrees. The qulity of n Richrd E. Powers, MD (7) Bureu of Geritric Psychitry/DETA --7

2 eductionl experience is difficult to mesure; producing cler limittions to this type of reserch..7 Most studies demonstrte reltionship between cdemic chievement nd dementi (See Tble ). Persons with the lowest eductionl levels tend to hve the gretest risk for developing dementi in lter life nd fster rte of cognitive decline (See Tble ). Gender nd ethnic differences do not pper significnt; however, Africn-Americn elders with miniml eduction who reside in rurl res pper to hve some of the gretest risks for developing dementi. Lifetime professionl chievement nd socioeconomic strt re often reflective of eductionl opportunities. Individuls with low socioeconomic strt my hve greter risk for developing dementi. Lifetime lerning nd cdemic stimultion my provide beneficil effect to some persons. Tble. Eduction nd Risk of Dementi in nd PD Tble. Eduction nd Rte of Cognitive Decline Study n AF-AM yrs Dose dependent risk for eduction A Study n AF-AM yr. eduction = rte of decline A 77 8 SES = risk A 9 NA yr. eduction = rte of decline A % OR=.77 risk for eduction nd.7 in twins X risk of dementi in low educted AF-AM vs high eduction Cucsin A A 8. eduction = rte of decline eduction = rte of decline trining = rte of decline A7 A8 A9 7 eduction = risk in PD Eduction = protective effect A A <% yr. eduction = rte of decline post CVA on MRI A Eduction Eduction The Impct Of Eduction Or IQ On Functionl Imging Results Brin metbolic behvior determined by PET or SPECT scnning my reflect the integrity of neuro-circuits producing the signl. Multiple PET nd SPECT studies using mrkers for blood flow nd glucose metbolism (See Tble ) hve exmined the reltionship between eductionl level, intellect, nd dementi. Individuls with higher cdemic chievement or clculted intellect pper to hve incresed blood flow in criticl brin regions. Cognitive trining ppers to enhnce brin ctivtion bsed on functionl imging. Individuls with higher intellect demonstrte more serious defects in brin imging. This suggests tht individuls of higher intellect my be ble to sustin greter brin dmge before they exhibit symptoms of dementi - - mnifesttion of the cognitive reserve hypothesis. Tble. Eductionl Correlte to Functionl Imging for Norml nd Imge Dx PET, rcbf, FDG eduction = dmge with function B 8 SPECT, rcbf eduction = perfusion B PET, rcbf, FDG eduction = flow B SPECT, rcbf eduction = flow in B 9 FDG, PET eduction = flow in B fmri trining = ctivtion B Eduction Richrd E. Powers, MD (7) Bureu of Geritric Psychitry/DETA --7

3 .7 Reltionship Between Brin Pthology And Acdemic Achievement Severl studies hve exmined the reltionship between the severity of brin dmge, cognitive symptoms, nd eductionl sttus (See Tble ). Studies suggest tht the severity of neurofibrillry degenertion or vsculr injury is unrelted to cognitive function s dependent upon eductionl sttus. The clinicl effect of specific levels of neuritic plques or myloid deposits ppers prtilly medited by the person s eductionl level. In short, person of high eductionl bckground my tolerte higher densities of senile plques or myloid deposits s compred to infrcts or neurofibrillry tngles. Tble. Brin Neuropthology nd Eduction 7 87 Comments No reltionship between eduction nd severity of pthology Eduction = vsculr dmge but no effect on -NP G G Eduction = impct of myloid but not NFT s G 8 Eduction only modified effect of neuritic nd diffuse plques (p=.) Infrcts predict cognitive decline in lower IQ better thn lone -NP G G Eduction Conclusions About The Role Of IQ And Acdemic Achievement As Risk Fctors For Developing Dementi In Lter Life IQ nd cdemic chievement plys some role in predicting the overll risk for developing dementi. Epidemiologicl, brin imging, nd neuropthologicl studies suggest tht persons in the lowest qurtile of cdemic chievement my exhibit greter risk for developing dementi in lter life. This ffect my result from mny fctors including: ) reduced cognitive reserve, ) lower socioeconomic strt with diminished ccess to helthcre resources, ) poor helth litercy nd complince, ) nutritionl issues relted to socioeconomic strt, nd mny other confounding vribles. Litercy my ply vluble role in determining person s eductionl risk. Lifetime cdemic chievement my tke mny forms bsed on culturl nd socioeconomic issues. Neuropsychologicl testing nd dementi screening must be interpreted in the context of the person s premorbid function. For instnce, persons with significnt cognitive impirment my score normlly on stndrd screening instrument if they hd high lifetime intellectul chievement. Ptients should be encourged to mintin intellectul vitlity nd ctivities throughout life. Reding, writing, nd socil enggements tht require ctive thoughtful interctions my ply positive roles in mintining intellectul function into lter life. The potentil cognitive benefit of lifetime cdemic chievement is not seen with vsculr dmge to the brin nd reduction of cerebrovsculr risk fctors is n importnt component to ll cognitive wellness progrms. Mentl Retrdtion As A Risk Fctor For Dementi Persons with mentl retrdtion hve greter risks for developing dementi with ging. Certin cuses of dementi such s Down s syndrome or Frgile X crries significnt risks for neurodegenertive disorders in lter life. Persons with intellectul disbility should be included in your high risk groups when considering the possibility of dementi. Richrd E. Powers, MD (7) Bureu of Geritric Psychitry/DETA --7

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