Rev. Bras. Anestesiol. vol.67 número4

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REVISTA

BRASILEIRA

DE

ANESTESIOLOGIA

PublicaçãoOficialdaSociedadeBrasileiradeAnestesiologia

www.sba.com.br

SCIENTIFIC

ARTICLE

Impact

of

postoperative

cognitive

decline

in

quality

of

life:

a

prospective

study

Joana

Borges

a

_,

_Joana

_Moreira

a

_,

_Adriano

_Moreira

a

_,

_Alice

_Santos

a

_,

Fernando

J. Abelha

a,b,∗

a_Centro_Hospitalar_de_São_João,_Servic_¸o_de_{Anestesiologia,}_Porto,_Portugal

b_Faculdade_de_Medicina_da_Universidade_do_Porto,_Departamento_de_Cirurgia,_Unidade_de_{Anestesiologia}_e_Medicina Perioperatória,Porto,Portugal

Received17September2015;accepted20July2016 Availableonline29August2016

KEYWORDS

Postoperativecare; Postoperative cognitivedecline; Qualityoflife

Abstract

Background: Regardless the progress in perioperative care postoperative cognitive decline (PCD)hasbeenacceptedunequivocallyasasignificantandfrequentcomplicationofsurgeryin olderpatients.Theaimofthisstudywastoevaluatetheincidenceofpostoperativecognitive declineanditsinfluenceonqualityoflifethreemonthsaftersurgery.

Methods:Observational,prospectivestudyinaPost-AnesthesiaCareUnit(PACU)inpatients agedabove45years,afterelectivemajorsurgery.CognitivefunctionwasassessedwithMontreal Cognitive Assessment (MOCA);Qualityof life(QoL) was assessedusing SF-36Health Survey (SF-36).Assessmentswereperformedpreoperatively(T0)and3monthsaftersurgery(T3). Results:Forty-onepatients werestudied. TheincidenceofPCD3months aftersurgerywas 24%.AtT3MOCAscoreswerelowerinpatientswithPCD(median20vs.25,p=0.009).When comparingthemedianscoresforeachofSF-36domains,therewerenodifferencesbetween patientswithandwithoutPCD.In patientswithPCD,andcomparingeachofSF-36domains obtainedbefore andthreemonthsafter surgery,hadsimilarscoresfor everyofthe8SF-36 areaswhilepatientswithoutPCDhadbetterscoresforsixdomains.AtT3patientswithPCD presentedwithhigherlevelsofdependencyinpersonalactivitiesofdailyliving(ADL). Conclusion:ThreemonthsaftersurgerypatientswithoutPCDhadsignificantimprovementin MOCAscores.PatientswithPCDobtainednoincreaseinSF-36scoresbutpatientswithoutPCD improvedinalmostallSF-36domains.PatientswithPCDpresentedhigherratesofdependency inpersonalADLaftersurgery.

∗_{Corresponding}_author.

E-mail:[email protected](F.J.Abelha).

http://dx.doi.org/10.1016/j.bjane.2016.07.012

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PALAVRAS-CHAVE

Cuidado pós-operatório; Declíniocognitivo pós-operatório; Qualidadedevida

Impactododeclíniocognitivopós-operatórionaqualidadedevida:estudo prospectivo

Resumo

Justificativaeobjetivo: Independentedoprogressodotratamentonoperíodoperioperatório, odeclíniocognitivonopós-operatório(DCPO)éinequivocamenteaceitocomoumacomplicação importanteefrequentedacirurgiaempacientesmaisvelhos.Oobjetivodesteestudofoiavaliar aincidênciadeDCPOesuainfluêncianaqualidadedevidatrêsmesesapósacirurgia. Métodos: EstudoprospectivoobservacionalconduzidoemSaladeRecuperaçãoPós-anestesia (SRPA)compacientesdeidadesuperiora45anos,apóscirurgiaeletivadegrandeporte.Afunção cognitivafoiavaliadacomotestedeAvaliaçãoCognitivadeMontreal(MOCA)eaqualidadede vida(QV)comoQuestionáriosobreQualidadedeVida(SF-36).Asavaliaçõesforamrealizadas nopré-operatório(T0)etrêsmesesapósacirurgia(T3).

Resultados: Foramavaliados41pacientes. Aincidência deDCPOtrêsmesesapósacirurgia foide24%.EmT3,osescoresMOCAforammenoresnospacientescomDCPO(mediana20vs. 25, p=0,009).Ao compararas medianasdos escorespara cada um dosdomíniosdo SF-36, não observamos diferençasentreos pacientescome semDCPO.Aocomparar cadaumdos domíniosdoSF-36obtidosanteseapóstrêsmesesdecirurgia,ospacientescomDCPO apre-sentaramresultadossemelhantesparacadaumadasoitoáreasdoSF-36,enquantopacientes semDCPOapresentaramresultadosmelhoresemseisdomínios.EmT3,ospacientescomDCPO apresentaramníveismaiselevadosdedependêncianarealizaçãodeatividadescotidianas. Conclusão:Três mesesapósacirurgia,os pacientessemDCPO apresentarammelhora signi-ficativa dosescores MOCA.OspacientescomDCPO não apresentaram aumentodosescores SF-36,masospacientessemDCPOapresentarammelhoraemquasetodososdomíniosdo SF-36.OspacientescomDCPOapresentaramtaxasmaiselevadasdedependêncianarealização deatividadescotidianasapósacirurgia.

Introduction

Regardlesstheprogressinperioperativecare,postoperative

cognitivedecline(PCD)hasbeenacceptedunequivocallyas

asignificantandfrequentcomplicationofsurgeryinolder

patients.1---12 _However,_there_is_still_no_consensus_definition

ofPCDinthemedicalcommunity,andbroadly,itrefersto

atemporarydeclineincognitionassociatedwithsurgery.13

Ifitlastlongerthanthreemonthsis definedaslong-term

postoperativecognitivedecline,13,14_and_a_considerable pro-portionofpatientsdonotrecoverthreemonthsaftersurgery (7---69%incardiacsurgery).15

The exactetiologyofPCDremainsunclearandis

prob-ablymultifactorial.15,16 _{Complications}_in_the_{perioperative} periodmayanticipateearlyPCD,butincreasingagehasbeen

shown to bea significant and independent risk factor for

PCD.The incidenceof PCDisexpectedtoincrease asthe

populationofoldersurgicalpatientsgrows.11,17

Patients submitted to cardiac surgery have been

pro-fusely studied, however, the incidenceand prevalence of

thiscomplicationafterothertypesofsurgeryhasnotbeen

so exhaustively reported.16,18 _The _{International} _Study _of

Postoperative Cognitive Dysfunction (ISPOCD) group

stud-ied 1218 patients aged 60 years old or older, undergoing

majorgeneralsurgeryandreportedanincidenceofPCDof

25.8---9.9%, oneweek andthreemonths followingsurgery,

respectively.6 _However,_the_estimation_of_the_frequency_of

PCDstillvariesfrom25%to80%.4

The diagnosis of PCD requires valid and accurate

pre-operativeandpostoperativeneuropsychologicaltestingand

thedeterminationofacut-offpointbetweenPCDand

nor-malvariationincognitiveperformance.PCDdiagnosisisnot easytoperformandithasnoapparentclinicalsymptoms

---patientsmaypresentanimpairmentinoneorvarious

cog-nitive abilities suchas memory,attention, concentration,

speedofmotorandmentalresponse,informationprocessing

and learn after surgery and anesthesia that is different

fromdelirium.4,13,19_It_has_a_subtle_manner_of_{manifestation,}

commonlymany daysor weeks aftersurgery.2,4 _Numerous

cliniciansfail torecognizethe subject’s cognitivedecline

followingsurgery;butalsothepatientsthemselves,dueto

inattentionor embarrassment,may notbeawareof their

PCDor bereluctant toreport any alteration.4 _Until _now,

thereis no standard accepted approach for its diagnosis,

anditisessentialuseseveralvalidandhighlysensitive

neu-ropsychologicaltests,whichallowassessingmanycognitive

areas.4,19---21

Althoughcognitivechangesarenotmanifestedclinically

insomepatients,recentstudiesshowthatPCDmayleadto

aprolongedhospitalstay,elevatedmedicalcosts,increased

morbidityand readmission tohospital.PCDhas long-term

consequencesintermsofincreasedall-causemortalityand

declined in Quality of Life (QoL), associatedwith

impair-mentsin dailyfunctioning,prematuredeparturefromthe

labormarket,anddependencyoneconomicassistanceafter

(3)

Thepurposeofthisstudywastoassesstheincidenceof

PCDandcognitiverecovery3monthsfollowingnon-cardiac

andnon-neurologicalsurgeryandtodeterminetheimpact

ofcognitivedeclineinQoLanddependencyinactivitiesof

thedailyliving.

Methods

Ethics

Ethicalapprovalforthisstudy(EthicalCommitteeapproval

n◦

127/12)wasprovidedbyComitédeÉticaparaaSaúdedo

CentroHospitalardeSãoJoão,Porto,Portugal(Chairperson:

ProfessorFilipeAlmeida)onMay25,2012.Writtenconsent

wasobtainedfromallpatients.

Thecohort

Atotal of221 patients undergoingelective majorsurgery

wereenrolled in the study, conductedfrom 18thJune to

15th July 2012, in the multidisciplinary Post-Anesthesia

Care Unit (PACU). The inclusion criteria involved adult

Portuguese-speaking patients submittedtomajor elective

surgery(definedassurgerythatrequirestwoormoredays

of hospital stay) requiring anesthesia, aged 45 years old

and older. Patients could not be included twice, even if

theyhadanunrelatedsecondprocedure.Patientswerealso

excludedif they(1)hadcognitiveimpairment atbaseline

assessmentconsideredforpatientswithaMini-MentalState

Examination(MMSE)score22_of_less_than_24;₍₂₎_had_not

pro-videdorwereincapableofprovidinginformedconsent;(3)

wereunabletounderstandthelanguageusedorwere

illit-erate; (4) were unwilling tocomply withthe protocol or

procedures;(5)hadbeensubmittedtourgentoremergent

surgery;(6)hadbeen admittedforobstetric,neurological

orcardiacsurgery;and(7)wereadmittedtointensivecare

units for postoperative vigilance. All patients were

inter-viewed either on the eve or the day of the surgery (at

least3h before). Itwasthen conductedasmall

consulta-tiontoobtainconsent,toperformMMSEtestandtocollect

the medical history. Patients completed

neuropsychologi-caltestsatentrytothestudy(T0)andthreemonthsafter

surgery(T3). These testsincluded the Montreal Cognitive

Assessmenttest(MOCA),23 _the_Medical_Outcomes_Study₃₆

items Short Form Health Survey test (SF-36),24 _the

Law-toninstrumentalactivitiesofthedailylivingscale(Lawton

scale)25 _and _the _Katz _Index _of _Independence _in _activities

ofthe daily living(Katz’s Index).26 _{Anesthesiologists}_were

blinded to patient involvement in the study. Conduct of

anesthesia,includingthechoice ofthetypeof anesthesia

wasatthediscretionoftheanesthesiologist.

Patientassessment

The recordedpatients’ characteristics were:age, weight,

height, body mass index (BMI) and American Society of

Anaesthesiologists Physical Status (ASA-PS). The Revised

CardiacRiskIndex(RCRI)wasalsocalculated,usingthe

clas-sificationsystem reportedby Lee etal.,27 _which _includes

high-risk surgery (i.e., intraperitoneal, intrathoracic, or

suprainguinalvascularprocedures)andclinicalriskfactors:

history of ischemic heart disease, compensated or prior

heart failure, cerebrovascular disease, diabetes mellitus

andrenalinsufficiency.Thesevariablesareincludedinthe

Cardiac Risk Stratification for Non-cardiac Surgical

Proce-duresofthe2007guidelinesonPerioperativeCardiovascular

EvaluationandCarefor Non-cardiacSurgeryof the

Ameri-canCollegeofCardiology/AmericanHeartAssociationTask

ForceonPracticeGuidelines.28

Intraoperative details, including type and duration of

anesthesiaandsurgicalprocedures,lengthofPACUstayand

any cardiorespiratory events in this unit were also

docu-mented.

EvaluationofPCDandqualityoflife

Each participantunderwent neuropsychological testing at

two-timepoints:preoperatively(T0)andthreemonthsafter

surgery(T3).

Allpatientscompletedbaselineassessmentsof general

cognitive functioning assessed by the Mini-Mental State

Examination.MMSEisavalidandrecognizedtest,performed

in5---10min;thatevaluatescognitivestatus.Itgrossly

evalu-atesexecutivecognitivefunctionbymeasuringorientation,

calculations,memory, readingandwriting capacities,

lan-guage andvisuospatialability. Even so,patients withmild

forms of cognitivedecline frequently scorein the normal

rangeintheMMSE.22

Montrealcognitiveassessment testis aone-page

ques-tionnaire that takes 10min to perform and is suitable to

evaluateshort-termmemory,executivefunctions, working

memory, concentration, visuospatial abilities, attention,

language,andtemporalandspatialorientation.The score

rangevariesfrom0to30,andhigherscoresindicatebetter

cognitive performance. To adjust for educational effects,

subjects with 12 or fewer years of education receive

an extra point.23,29,30 _Several _studies _were _conducted _in

Portugal concerning the Portuguese experimental version

oftheMOCA,andthestudies’conclusionsappeartoassure

thevalidityandclinical utilityofthistool.30 _Adopting _the

criterion usedby Baracchini et al.1 _a _decline _of _at _least

2 points in MOCA test at T3 was considered as clinically

relevantanddefinedasPCD.

TheMedicalOutcomesStudy36ItemShortFormHealth

Survey24_aims_to_quantify_general_health_condition_and

con-sistsofeightsectionsordomains, whicharetheweighted

sums of thequestionsin their section.The eightdomains

arevitality,physicalfunctioning,bodilypain,generalhealth

perceptions,physicalrolefunctioning,emotionalrole

func-tioning, social role functioning, and mental health. This

questionnairehasalsobeenculturally adaptedtothe

Por-tugueseandvalidatedinastudybyFerreiraetal.31,32 Evaluationoffunctionalcapacitywasbasedontheability ofthepatienttoundertakepersonalandinstrumental activ-itiesofdailyliving.Todoso,twoquestionnairesthatassess

thefunctional independenceof thesubjecttoaccomplish

instrumental ADL (I-ADL) and personal ADL (P-ADL) were

used:theLawtonI-ADLscale25_and_the_Katz’s_Index_of

Inde-pendence in ADL, respectively.26 _The _Lawton _I-ADL _scale

is easy to perform and provides self-reported knowledge

about the functional skills needed to live in the

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Table1 Pre-admissionpatientcharacteristicsandoutcomes(n=41).

Variable---n(%)ormedian(IQR) All n=41

NoPCD n=31(76)

PCD n=10(24)

p

Age(years) 64(57---70) 63(56---69) 67(60---73) 0.354a

Agegroup(years) 0.171b

<65 24(59) 20(64) 4(40)

>65 17(41) 11(36) 6(60)

Gender 0.610b

Male 13(32) 10(32) 3(30)

Female 28(68) 21(68) 7(70)

ASA-PS 0.642b

I/II 33(80) 25(81) 8(80)

III/IV 8(20) 6(19) 2(20)

Bodymassindex(kg/m2₎ ₂₇_(25---30) ₂₇_(25---30) ₂₇_(26---31) _0.554a

Durationofanesthesia(min) 120(90---166) 120(75---166) 124(108---169) 0.594a

Typeofanesthesia 0.181a

General/combined 32(78) 24(77) 8(80)

Locoregional 9(22) 7(23) 2(20)

Siteofsurgery 0.453

Abdominal 24(59) 18(58) 6(60)

Musculoskeletal 13(32) 9(29) 4(40)

Headandneck 4(10) 4(13) 0

TemperaturePACUadmission(◦_C) _35.6_{(35.0---36.1)} _35.8_{(35.2---36.1)} _35.0_{(34.6---35.8)} _0.170a

Hypertension 28(68) 23(74) 5(50) 0.150b

Hyperlipidemia 22(54) 16(52) 6(60) 0.463b

COPD 4(10) 3(10) 1(10) 0.689b

STOP-Bang≥3 29(71) 23(74) 6(60) 0.316

High-risksurgery 13(32) 9(29) 4(40) 0.390b

Ischemicheartdisease 4(10) 4(13) 0 0.390b

Congestiveheartdisease 1(2) 1(3) 0 0.756b

Cerebrovasculardisease 1(2) 0 1(10) 0.244b

Renalinsufficiency 2(5) 13) 1(10) 0.433b

Insulintherapyfordiabetes 5(12) 4(13) 1(10) 0.647b

Benzodiazepines 11(27) 8(26) 3(30) 0.546

Benzodiazepinespremedication 12(29) 9(29) 3(30) 0.302

PACUlengthofstay(min) 110(90---138) 110(90---140) 110(58---129) 0.670a

PCD,postoperativecognitivedecline;IQR,interquartilerange;ASA-PS,AmericanSocietyofAnesthesiologistsphysicalstatus;COPD,

chronicobstructivepulmonarydisease;PACU,Post-AnesthesiaCareUnit.

a _{Mann---Whitney}_U_test.

b _Pearson

2.

finances,shopping,housekeeping,foodpreparation,public

transportationandresponsibilityforownmedications.25_The

KatzADLscaleevaluatesbasicpersonalADLandranks

capa-bilityofperformancein6areas:bathing,dressing,goingto

the toilet,transferring frombed tochair, continence and

feeding.25_The_patients’_answers_were_categorized_into_two

classes: capable or incapable toperform each activity or

groupofactivities.Theywereconsideredtobedependentif

theywereincompetenttoperformatleastoneinstrumental

orpersonalADL.

Statisticalanalysis

Descriptive analysis of variables was used to summarize

data. Ordinal and continuous data found not to follow a

normaldistribution,basedontheKolmogorov---Smirnovtest

for normalityof the underlyingpopulation, arepresented

as median and interquartile range (IQR). Normally

dis-tributeddataarepresentedasmeanandstandarddeviation

(SD).Non-parametrictestswereperformedforcomparisons

(WilcoxsignedranktestandtheMann---WhitneyUtest).The

chi-squaretestorFisher’sexacttestwereusedtocompare

proportions between twogroups of subjects. The related

samplesWilcoxonsignedranktestwasusedtocompare

SF-36 scores before surgery and three-months after surgery.

Differenceswereconsideredstatisticallysignificantwhenp

was<0.05. SPSS softwarefor Windows Version 20.0 (SPSS

Inc.,Chicago,IL,USA)wasusedforallstatisticalanalyzes.

Results

Fromthe221patientsconsecutivelyadmittedinthePACU

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Table2 SF-36inpatientswithPCD.

T0(median) T3(median) p

Physicalfunction 83 75 0.779

Rolephysical 59 56 0.635

Bodilypain 43 67 0.314

Generalhealth 53 49 0.674

Vitality 40 44 0.905

Socialfunctioning 75 69 0.918

Roleemotional 79 75 0.921

Mentalhealth 52 58 0.818

SF-36,36-Item ShortFormHealth Survey;PCD,postoperative cognitivedecline;T0,beforesurgery;T3,3monthsaftersurgery.

Table3 SF-36inpatientswithnoPCD.

T0(median) T3(median) p

Rolephysical 50 63 0.021a

Bodilypain 62 74 0.022a

Generalhealth 57 65 0.016a

Socialfunctioning 75 100 <0.001a

Roleemotional 67 92 0.014a

Mentalhealth 52 68 <0.001a

SF-36,36-Item ShortFormHealth Survey;PCD,postoperative

cognitivedecline;T0,beforesurgery;T3,3monthsaftersurgery.

a_{Statistically}_significant,_p_<_0.05.

One-hundredsixty-threepatientswereexcluded,according

totheexclusioncriteria:21couldnotperformpreoperative assessment,112hadlessthan45yearsold,12patientswere

admittedtoasurgicalintensivecareunit,8patientswere

unabletoprovideinformedconsentorhadanMMSE<24,2

patientsdidnotundergosurgery,2patientsunderwent

neu-rosurgery,3patientsdidnotspeakPortugueseand3patient

refusedtoparticipate.Fromtheremaining57patients,only

41 patients have completed all evaluations for cognitive

assessmentandqualityoflifeatthreemonthsfollow-up.

The characteristics of the population are summarized

in Table1. The median age was 64years old.78% of the

patientsunderwent generalor combinedanesthesia

(gen-eralpluslocoregionalanesthesia,andthemediantimefor

itsdurationwas120min.Gastrointestinalsurgeryaccounted

for)49%ofthecases,plasticandreconstructivesurgeryto

15%,gynecologicsurgeryandorthopedics,each10%,

urol-ogyto8%,vascularto4%,headandnecksurgeryto3%and

otorhinolaryngologyto1%ofthecases.Nostatistically

sig-nificantdifferencesbetweenpatientswithandwithoutPCD

wererecordedforthestudiedvariables.

The incidenceofPCD,3monthsaftersurgery,was24%

(n=10).AtT0,nodifferencesemergedfortheMOCAscores

between patients withand without cognitive impairment

(median25vs.21,p=0.139).AtT3,however,patientswith

PCDhadworsemedian MOCAscores(20vs.25,p=0.009).

ComparingtopreoperativeMOCAscores,PCDpatientshad

worseMOCAmedianscoresatT3(20vs.25,p=0.001),while patientswithoutPCDhadbetterscores(25vs.21,p<0.001).

Tables2 and3presentmedianscores ofSF-36domains

forbothgroupsofpatients,comparingT0andT3score.For

Table4 Comparinggroups withandwithout PCDbefore

surgeryforSF-36(T0).

SF-36domains WithoutPCD WithPCD p

Social 75 75 0.736

SF-36, 36-ItemShort FormHealth Survey;PCD,postoperative cognitivedecline;T0,beforesurgery.

Table5 ComparinggroupswithandwithoutPCDforSF-36

3monthsaftersurgery(T3).

NoPCD (median)

PCD (median)

p

Socialfunctioning 100 69 0.200

SF-36, 36-ItemShort FormHealth Survey;PCD,postoperative cognitivedecline;T3,3monthsaftersurgery.

patientswithPCD,andcomparingeachofSF-36domainsat T0and T3,therearesimilarscores for everyof theeight SF-36domains(Table 2).Patientswithout PCDhad better scoresatT3insixdomains(Table3):rolelimitationscaused

by physicalproblems (median 63vs.50, p=0.021),bodily

pain(median74 vs.62,p=0.022), generalhealth

percep-tion(median65vs.57,p=0.016),socialfunctioning(median 100vs.75,p<0.001),rolelimitationscausedbyemotional

problems (median 92vs. 67, p=0.014)and mentalhealth

(median68vs.52,p<0.001)andtheyhadsimilarscoresfor vitality(p=0.208)andphysicalfunction(p=0.289)domains.

Tables4 and5 present themedian scores for allSF-36

domains obtained before and after surgery, respectively,

comparingpatientswithandwithoutPCD.Asexhibited,at

T0andT3allscoresforSF-36domainsweresimilar.

InTable6itisshownthatatT0thereweresimilarrates

ofdependencyinP-ADLandI-ADL,whencomparingpatients

with and without PCD; however, at T3 patients with PCD

presented withhigherlevelsofdependency inP-ADL (50%

vs. 16%, p=0.030). Comparing their rates of dependency

at T0withT3and forpatients withPCDthereis ahigher

dependencescoresinI-ADL(50%vs.10%,p=0.037)butnot

for P-ADL (10% vs. 10%, p=1.0).In the samecomparison,

patients withoutPCDhad nodifferencesinI-ADL(29% vs.

(6)

Table6 Independencyinactivitiesofdaily livingbefore andaftersurgery.

ADL NoPCD

(n=31)

PCD (n=10)

p

I-ADLatT0,n(%) 2(7) 1(10) 0.578 P-ADLatT0,n(%) 7(23) 1(10) 0.358 I-ADLatT3,n(%) 1(3) 1(10) 0.433 P-ADLatT3,n(%) 5(16) 5(50) 0.030*

ADL, instrumental activities of daily living; P-ADL, personal activitiesofdailyliving;T0,beforesurgery;T3,3monthsafter surgery.

Discussion

WereportanincidenceofPCDof24%,threemonths follow-ingsurgery.Inliterature,theincidenceofPCDisnotclearly definedandmayvarybetween25%and80%.4,13_Many_current reportsestablishthatsurgery,particularlycardiacsurgery,

mayresultinPCDandthatitsincidenceincreaseswithage,

independentlyoftheanesthetictechnique.11

PCD can have a considerable impacton qualityof life

andmayresultinwithdrawalfromsociety.11,13,15,17_In_recent

years, PCDafter non-cardiac surgery has been

systemati-callystudied.InparticulartheISPOCD(InternationalStudy

groupofPostoperativeCognitiveDysfunction)was

success-fulinuncoveringtheextentoftheproblemanddefiningrisk

factors.EarlyPCDoccursinapproximately25%ofpatients

oneweekaftersurgery,andthendeclinestolessthan10%

afterthreemonths.6

PCD refers to deterioration in cognition temporally

associated with operation; thus, the growing number of

elderly patients undergoing surgery should aware

anes-thesiologists and surgeons to its serious repercussions.11

Nevertheless,thereisnoexplicitinformationifanychange

in procedures would change the incidence of PCD,but it

is possible that preoperative medication, anticholinergic,

catecholamine’s, and some events such as hypotension,

hypothermia,hypoxia,cerebralatheroembolismor

hypoper-fusion, poorglycemic controland carotidendarterectomy

maycontributetohighincidencelevelsofPCD.2_In_our_study,

wedidnotfounddifferencesrelatedtopatientdemographic

variablesoranesthesiaorsurgicalcharacteristics.

InthemultiplePCDstudiestherehasnotbeenastandard

methodology used33 _and _the _choice _of _{neuropsychological}

testinstruments,thecriteriatoconsider,thetimingof test-ingandretesting,andinclusionandexclusioncriteriahave allvaried.34

The use of highly sensible and specific

neuropsycholo-gicaltests allowsfortheidentification of subtlecognitive deficitswithexcellenttest/retestvalidity,butwithhighest riskoftypeIIerrors(failingtodetectPCD).Forthisstudy,

theMOCAtestwaschosen becauseit iseasy andquickto

perform and enables the evaluation of several functional

domainsofcognition.Evenso,itmayfailtoidentifysome

patientswithmilderformsofPCD.35,36

Perioperative interventions have long-range effects on

theindividual,sostrategiestopreservelong-termcognitive performanceandqualityoflifearerequired.37

The risk of cognitivedecline increaseswith ageand is

furtherenhanced after hospitalizationfor surgery,

result-ing in significant morbidity and reduced quality of life.38 Actually,thereisnoindividualapproachtoavoidcognitive

deterioration2 _but _the _maintenance_and/or _restoration_of

functionalindependence,includingcognition,intheelderly

hospitalizedpatientconstitutesamajorchallengefor the

healthcaresystem.

The postoperative cognitive decline may diminish

improvements in QOL and strategies to reduce

cogni-tive decline mayallow patients toachieve the maximum

improvementinQOLaftersurgery. Thishasbeen the

sub-ject of various studies7 _and _like _them _the _present _study

demonstratedthat cognitivedecline limitedimprovement

inQOL.

Even mild cognitive deficits before surgery may be a

markerforincreasedriskofcognitivedecline39 _and_also_it

hasbeen accepted that PCDgenerally resolvewithin 1---3

monthsinmostpatientsinwhomnewcognitivesymptoms

developduringpostoperativeperiod.33,39,40

Threemonthsaftersurgeryasignificantimprovementin

qualityof life in patients without PCD wasdemonstrated

byan increase in almost all scores of SF-36domains, but

amongstpatientswithPCD,noimprovementwasseeninany

oftheSF-36scores.Thislimitationinqualityimprovement

isalsodemonstratedinPCDpatientsbyasignificantmore

dependencyinP-ADLthreemonthsaftersurgerycomparing

withpatientswithoutPCD.

Thisstudyhasseverallimitations.Itisanobservational study,withasmallsampleofpatients.Ithasmanydropouts andlossestothefollow-up(explained,inpart,bytheneed

tohavecomplete interviewsbeforeandafterthesurgery,

forfollow-upconsultation).Furthermore,wedidnot

stud-iedclinicalvariablesaftersurgery,includingcomplications

andmedicationsthatmayhaveaffectednotonlythelosses

tofollow-upbutalsotheresultsincognitiveperformance,

qualityoflifeandindependenceinADL.

Conclusions

Theprincipalfindingsofthisstudywereasfollow:(1)the

incidenceofPCDwasof24%;(2)patientswithPCDshown

noimprovementsinqualityoflifescores;and(3)patients

withoutPCDshownbetterscoresinalmostallSF-36domains

andanincreaseindependency,aftersurgery.

PCD is a real event, with realcomplications and

con-sequences in the quality of life, which requires a better

understanding, especially in terms of etiologic factors in

ordertoprevent them.It shouldnotbe overestimatedas

itdecreasesthequalityoflifeandenhancesthedegreeof

dependencefor activities of daily living, andhigh-quality

perioperativecareandsupportaresocialandfinancialare

essential.

Authorship

Allauthorsconfirm thattheyhaveread andapprovedthe

paper.

Allauthorsconfirm that theyhavemet thecriteriafor

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paperrepresentshonestwork, andcan verifythe validity oftheresultsreported.

All persons designated, as authors are qualified for

authorship.

Eachauthorparticipatedsufficientlyintheworktotake

publicresponsibilityforappropriateportionsofthecontent.

Allauthorshavesubstantialcontributionstoconception

anddesign,acquisitionofdata,analysisandinterpretation ofdata,draftingthearticleorrevisingitcriticallyfor impor-tantintellectualcontent.

Allauthorsmadetheirfinalapprovaloftheversionifis

tobepublished.

Conflicts

of

interest

Theauthorsdeclarenoconflictsofinterest.

Acknowledgements

TheauthorswouldliketothanktheStaffofCentro Hospita-lardeSãoJoãoPost-AnesthesiaCareUnitfortheirassistance withthestudy.

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