Brain scans show lower accumulation of tau and amyloid pathology among cognitive “super-agers”

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– Tau (blue) and amy­loid (orange) dis­tri­b­u­tion pat­terns for super-agers, nor­mal-agers and MCI patients, when com­pared to a group of younger, healthy, cog­ni­tive­ly nor­mal, amy­loid-neg­a­tive indi­vid­u­als. Cred­it: Mer­le C. Hoenig.

Super-Agers Show Resis­tance to Tau and Amy­loid Accu­mu­la­tion, Main­tain High Cog­ni­tive Func­tion (Soci­ety of Nuclear Med­i­cine and Mol­e­c­u­lar Imag­ing press release):

Super-agers, or indi­vid­u­als whose cog­ni­tive skills are above the norm even at an advanced age, have been found to have increased resis­tance to tau and amy­loid pro­teins, accord­ing to research pre­sent­ed at the Soci­ety of Nuclear Med­i­cine and Mol­e­c­u­lar Imag­ing (SNMMI) 2020 Annu­al Meet­ing. An analy­sis of positron emis­sion tomog­ra­phy (PET) scans has shown that com­pared to nor­mal-agers and those with mild cog­ni­tive impair­ment, super-agers have a low­er bur­den of tau and amy­loid pathol­o­gy asso­ci­at­ed with neu­rode­gen­er­a­tion, which prob­a­bly allows them to main­tain their cog­ni­tive per­for­mance. An image show­ing the com­par­i­son of tau and amy­loid dis­tri­b­u­tion pat­terns in these dif­fer­ent cog­ni­tive aging tra­jec­to­ries has been select­ed as SNMMI’s 2020 Image of the Year.

“Our cog­ni­tion reflects who we are as indi­vid­u­als. As we age, most of us lose some of that abil­i­ty,” said SNMMI’s Sci­en­tif­ic Pro­gram Com­mit­tee chair, Umar Mah­mood, MD, PhD. “The Image of the Year pro­vides us with insight into how we can use these PET imag­ing bio­mark­ers to under­stand behav­iors and ther­a­pies that may allow more of us age bet­ter and retain more of our cog­ni­tive abil­i­ties as we get older” …

Data from the Alzheimer’s Dis­ease Neu­roimag­ing Ini­tia­tive was uti­lized to cre­ate three age- and edu­ca­tion-matched groups of 25 super-agers, 25 nor­mal-agers and 25 patients with mild cog­ni­tive impair­ment, all above 80 years old. In addi­tion, 18 younger, cog­ni­tive­ly nor­mal, amy­loid-neg­a­tive con­trols were includ­ed in the com­par­i­son as a ref­er­ence group.

The Study:

Resis­tance to Tau and Amy­loid Pathol­o­gy Facil­i­tates Super-Aging (The Jour­nal of Nuclear Med­i­cine). From the abstract:

  • Objec­tives: The phe­nom­e­non of select­ed indi­vid­u­als cog­ni­tive­ly per­form­ing above the norm even at high age (so-called super-agers) sug­gests that these indi­vid­u­als must obtain extra­or­di­nary resis­tance mech­a­nisms against brain aging process­es and/or neu­rode­gen­er­a­tion. How­ev­er, not much is known about age-asso­ci­at­ed mol­e­c­u­lar hall­marks of neu­rode­gen­er­a­tion in super-agers, par­tic­u­lar­ly con­cern­ing pro­teinopathies such as the accu­mu­la­tion of amy­loid-? and tau. There­fore, we com­pared the intrac­ere­bral amy­loid and tau bur­den in vivo in a group of super-agers (SA), nor­mal-agers (NA) and patients with mild cog­ni­tive impair­ment (MCI) using PET imaging.
  • Results: No sig­nif­i­cant dif­fer­ences between SA and YA (note: Younger Age con­trol group) were observed in terms of in vivo tau and amy­loid bur­den. The NA group exhib­it­ed high­er tau bur­den in infe­ri­or tem­po­ral and pre­cuneal areas and no sig­nif­i­cant dif­fer­ences in amy­loid bur­den, when com­pared to the YA group. The MCI patients showed both high amy­loid and tau pathol­o­gy bur­den. Dif­fer­ences in amy­loid bur­den pre­dict­ed NA from MCI, where­as low­er tau bur­den and low­er poly­genic risk pre­dict­ed SA from MCI.
  • Con­clu­sions: The phe­nom­e­non of super-aging appears to be asso­ci­at­ed with the resis­tance to tau and amy­loid pathol­o­gy, which like­ly per­mits main­te­nance of cog­ni­tive per­for­mance despite advanced age. In turn, dif­fer­ences between nor­mal aging and MCI appear to be dri­ven by the lev­el of amy­loid bur­den. These results moti­vate fur­ther research to deter­mine respon­si­ble resis­tance fac­tors, which may also inspire the devel­op­ment of nov­el treat­ment concepts.

The Study in Context: