The Economist - USA (2020-08-29)

TheEconomistAugust 29th 2020 3

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few daysshyofher90thbirthday,torturedbylegulcersand
arthritis,Vera,oneofsome850,000Britonswithdementia,
haskeptherselfalive,itseems,tomeetherfirstgrandchild,due
anymomentnow.Butwhenthehappydaycomesandthebabyis
broughttoher,sheisconfused.Sherecognisesherdaughter-in-
law,butispuzzledbythebundleinherarms.“That’snice,dear,”
shesays.“Butwhyhaveyoubroughtmea coconut?”
Dementiaisa cruelcondition,robbingpeopleoftheirdeepest
joysandhopes.Itmaystartasa“mildcognitiveimpairment”
(mci):forgetfulnessor“seniormoments”.Butasitprogresses,
attackingmentalagilityandeatingawaymemory,it stealsmuchof
whatcountsasidentity.Whensevere,peoplebecomeincapableof
lookingafterthemselves.Theylosetheabilitytoread,cookand
shop.Theyforgettodrinkandgetdehydrated,orbecomeinconti-
nent.Theysufferdelusions,orbecomefrightenedorangry,orthey
sinkintoanapatheticslump.Theyrequirecareforalltheirwaking
hours,andoftensupervisionwhenasleep.
Thecovid-19pandemichasbeena hugeordealforpeoplewith
dementia.Thelossofroutineandsocialcontactsunderlockdown
havehastenedcognitivedecline.Dementiapatientshaveproved
highlysusceptibletothevirus—inBritainsomestudiessuggestit
hasbeenthecommonest“pre-existingcondition”inthosedying
fromcovid-19.Anddeathswhere“dementia”hasbeenidentified
asthecausehavealsorisen.InAprilitcamesecondonlytoco-

vid-19.Thosewithdementiaoften haveconditionsthatmake

themvulnerable—aboveall,beingold,butalsobeingoverweight,

depressed,smoking,havinghighbloodpressureordiabetes.And

dementiamakesit hardtounderstandthedangerofthevirus,orto

remembersocial-distancingorhygieneprecautions.Manyhave

enduredthepandemicincarehomes,whichhaveaccountedfor

nearlyhalfofalldeathsfromcovid-19intherichworld.

Dementiaaffectsmorethan50mpeopleworldwide,a number

thatisrisingfast.Ithasmanycausesandisimperfectlyunder-

stood.Butnobodydoubtsthatitsprevalenceincreaseswithage.By

someestimates,1.7%of65-to69-year-oldshavedementia,andits

incidence(thenumberofnewcases)doubleseveryfiveyearsto

theageof90.Anotherestimateisthatattheageof85,betweena

thirdanda halfofpeoplehavedementia.

Inthissensedementiaiscollateraldamagefromoneofhu-

manity’striumphs:increasedlifespans.Ahundredyearsagolife

expectancyatbirthwasnotmuchmorethan30.By 1960 ithad

reached52.Todayitisabout 70 formenand 75 forwomen,andin

richcountries,over 80 apiece.Nonagenariansandevencentenari-

ansarenolongerrare.Despitecovid-19medicalprogresswillcon-

tinue,furtherlengtheninglives.Yetdementiaisstubbornlyresis-

tanttoeffortstofinda cure.Itwaslongseenasa naturalpartof

growingold,thelastofthesevenagesofmandefinedbyShake-

speare’sJaques:“secondchildishnessandmereoblivion”.Kate

The perilsof oblivion

Special report

Nowhere in the world is ready to cope with the global explosion of dementia, writes Simon Long

Dementia

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