Dor lombar inespecífica em adultos jovens: fatores de risco associados

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REVISTA

BRASILEIRA

DE

REUMATOLOGIA

ww w . r e u m a t o l o g i a . c o m . b r

Original

article

Nonspecific

low

back

pain

in

young

adults:

Associated

risk

factors

Rita

Neli

Vilar

Furtado

a,∗

,

Luiza

Helena

Ribeiro

a,b

,

Bruno

de

Arruda

Abdo

b

,

Fernanda

Justo

Descio

b

_,

_Celso

_Eduardo

_Martucci

_Junior

b

_,

_Débora

_Coutinho

_Serruya

b

a_Universidade_Federal_de_São_Paulo,_São_Paulo,_SP,_Brazil b_Universidade_Nove_de_Julho,_São_Paulo,_SP,_Brasil

a

r

t

i

c

l

e

i

n

f

o

Articlehistory:

Received15January2014

Accepted26March2014

Availableonline20August2014

Keywords:

Lowbackpain

Youngadults

Riskfactors

a

b

s

t

r

a

c

t

Objective:Theaimofthestudywastoevaluatepotentialriskfactorsrelatedtolowbackpain

inthedailyroutinesoftwosetsofyouths:individualscomplainingofchroniclowbackpain

andacontrolgroup.

Methods:The sample consisted of 198university-age students(male and female) aged

between18and29.Inaccordancewithbackpaindiagnoses,theywereseparatedintotwo

groups:withorwithoutnonspecificchroniclowbackpain.Bothgroupswereevaluatedbya

“blinded”observerwithnoknowledgetothepresenceorotherwiseoflowerbackpain.

Ques-tionnairesconcerningclinical-demographiccharacteristics,lifestyle,qualityoflife(SF-36

questionnaire),painvisualanalogicalscales(VAS),andphysicalexaminationwereapplied.

Results:Aunivariateanalysisshowedastatisticallysignificantassociation(P<0.05)with

thepresenceoflowbackpainandsomefactors.Therewasanegativeassociationbetween

lowbackpainandthefollowingvariables:BMI,healthself-assessment,VASandsome

SF-36domains(physicalfunctioning,bodypain,generalhealth,vitality,socialfunctioning).

Therewasapositivecorrelationwiththefollowingvariables:globalpainbyVAS,presence

ofdiffusepainandnumberoftenderpoints.However,themultivariateanalysisshowed

statisticallysignificantcorrelations(P<0.05)betweenlowbackpainandfewvariables:global

painVASandnumberoftenderpoints.

Conclusion: Somevariablesrelatedtochronicdiffusepainandlowerqualityoflifemight

beassociatedtochroniclowbackpaininyoungadults.However,longitudinalstudiesare

necessary.

DOIoforiginalarticle:http://dx.doi.org/10.1016/j.rbr.2014.03.018.

∗ _{Corresponding}_author.

E-mail:rvfurtado@hotmail.com(R.N.V.Furtado).

http://dx.doi.org/10.1016/j.rbre.2014.03.018

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Dor

lombar

inespecífica

em

adultos

jovens:

fatores

de

risco

associados

Palavras-chave:

Dorlombar

Adultosjovens

Fatoresderisco

r

e

s

u

m

o

Objetivo: Oobjetivodoestudofoiavaliarfatoresderiscopotenciaisparadorlombarna

rotinadiáriadedoisgruposdejovens:indivíduoscomqueixadedorlombareumgrupode

controle.

Métodos:Aamostraconsistiude198estudantesemidadeuniversitária(homensemulheres),

entre18e29anos.Deacordocomosdiagnósticosdedornascostas,osparticipantesforam

separadosemdoisgrupos:comousemdorlombarcrônicainespecífica.Ambososgrupos

foramavaliadosporumobservador“cego”,i.e.desconhecedordapresenc¸aoudequalquer

outraindicac¸ãodedorlombar.Foramaplicadosquestionáriosrelativosàscaracterísticas

clínico-demográficas,estilodevida,qualidadedevida(questionárioSF-36),dorpelaescala

visualanalógica(EVA)eexamefísico.

Resultados: Umaanáliseunivariadademonstrouumaassociac¸ãoestatisticamente

signi-ficativa(p<0,05)entrepresenc¸adedor lombarealgunsfatores.Houveumaassociac¸ão

negativaentredorlombareasseguintesvariáveis:IMC,autoavaliac¸ãodasaúde/EVAealguns

domíniosdoSF-36(func¸ãofísica,dorcorporal,saúdeemgeral,vitalidade,func¸ãosocial).

Houveumacorrelac¸ãopositivacomasseguintesvariáveis:dorglobalporEVA,presenc¸a

dedordifusaenúmerodepontossensíveis.Contudo,aanálisemultivariadademonstrou

correlac¸õesestatisticamentesignificativas(p<0,05)entredorlombarepoucasvariáveis:dor

globalporEVAenúmerodepontossensíveis.

Conclusão: Algumasvariáveisrelacionadasàdordifusacrônicaeàmáqualidadedevida

podemestarassociadasàdorlombarcrônicaemadultosjovens.Mashánecessidadede

estudoslongitudinais.

Introduction

Lowbackpainiscurrentlyoneofthemostwidespread

pub-lichealthproblemsfacedbythe industrialized world,asit

affects alarge portion ofthe population and constitutes a

heavy burden on national health and welfare systems in

termsofdiagnostics,treatment,absenteeismandearly

retire-ment.Addedtothatisthepsychosocialimpactcausedbythe

untimely withdrawalofotherwiseactive peoplefrom their

dailyactivities.1,2

Itisestimatedthatroughly 80%ofthe populationends

up suffering from back pain at some point in their lives.

Theoccurrenceofacutelowbackpainishigh,with

some-wherebetween15% and 30% ofthe population developing

thiscondition,mostlyinadulthood.Thatsaid,

epidemiologi-calstudieshaveshownanincreaseinmechanicallumbagoin

children,teenagersandyoungadults.Estimatesput

accumu-latedprevalenceinthispopulationat30%.3–5

Thesecondarycausesoflumbagointheyounger

popula-tionhasalwaysbeenamedicalconcern,asitisconsidered

a“redflag”whenbackpainaffectsthisagegroup.However,

nonspecificlowbackpainisstillthemaincauseamongthis

population.5

Previousstudieshavedetectedwhatareconsideredtobe

riskfactorspotentiallyleadingtothedevelopmentof

nonspe-cificbackpainamongchildrenandteenagers.Amongthese

arebiomechanicalalterationstothespinecausedby

mechan-icaloverburdening(heavyschoolbags,forexample),incorrect

postureandergonomic characteristicsofschoolchairsand

desks.6–12

The development ofnonspecific back pain can also be

tracedbacktothepracticeofcertainsportsduringchildhood

and/oradolescence.13–22

Aswithbackpainamongtheadultpopulation,otherrisk

factors for the development or worsening of lumbar pain

amongtheyoungaresedentarism,smokingandpsychosocial

alterations.13–17

Theaimofthepresentstudyistoevaluatetheexistence

ofpotentialriskfactorsrelatedtolowbackpainoralterations

inphysicalexaminationinthedailyroutinesoftwosetsof

youths,oneconsistingofindividualscomplainingofchronic

lowbackpain,andtheother,acontrolgroup,withnosuch

complaint.

Methods

Wecollected a representativesample of198university-age

studentsinSãoPaulo,Brazil.Thesampleconsistedofmales

andfemalesagedbetween18and29.Individualswithprior

diagnosisofsomespinalillnessorlowbackpainsuggestive

of secondarycauses, sciatica sufferersand those who had

previouslyundergonespinalsurgerywereexcludedfromthe

study.

Asdiagnosticcriteriafornonspecificchroniclowbackpain,

weusedthepersistenceofpainoveraperiodofthreemonths,

inaregionoftheback betweenthe lowermostriband the

glutealfold.18

Inaccordancewithchroniclowbackpaindiagnoses,

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Group1:Individualswithnonspecificchroniclowbackpain (NL)

Group2:Individualsnotsufferingfromnonspecificchronic

lowbackpain(NNL).Thisgroupincludedthosenotsuffering

fromnonspecificchroniclowbackatthetimeofthestudy,

andthosewhohadneverpresentedthesymptomsofchronic

lumbago.

Theindividualswerepickedandrandomlyincludedinthe

study.

Evaluation

Initially,theparticipantswereaskedtofillinaself-assessment

formandwerethenevaluatedbya“blinded”observerwithno

knowledgetothepresenceorotherwiseoflowerbackpain.

Questionnairesconcerningthe lumbarregion were applied

andphysicalexaminationswereconducted,asweretender

pointsfor“Fibromyalgia”.

Theself-assessmentformfurnishedthefollowing

informa-tion:

• Clinical demographic characteristics: color, gender, age,

weightandheight;

• Lifestyle andhabits:smoking,theuse ofalcoholorillicit

drugs,physicalexercise;

• Personalandfamilybackgroundswithregardtolowback

pain;

• Aspectsrelatedtomentalhealth:anxiety,emotional

insta-bility,sleepdisturbances.

• Visualanaloguescaleforlowbackpain:0-10cm(VASlow

backpain)

• General pain survey: notification of diffuse pain and

headache;visualanaloguescale fordiffusepain:0-10cm

(VASdiffusepain);notificationoftheuseofanalgesic

med-ications.

Thefollowingoutcomevariableswereappliedbytheobserver

blindedtothegroups:

• Visual analogue scale for generalhealth assessment:

0-10cm(VASgeneralhealth)

• SF-36HealthSurvey:qualityoflifequestionnaire19

• Standing toe-touch test: to assess flexibility of lumbar

region

• Schober’sTest:totestabilitytoflexlowerback

• Numberoftenderpoints:eighteenpointsintotal

StatisticalAnalysis

To compare the clinical demographic characteristics and

behavioralfactorsofthetwogroupsweusedStudent’sttest,

toanalyzecontinuousvariables,andthechi-square test,to

analyzecategoricalvariables.

Toevaluatetheassociationbetweeneachvariable

consid-eredapossibleriskfactorforlowbackpainandthepresenceof

lowerbackpain,weusedaunivariateanalysis.Thosefactors

forwhichstatisticallysignificantcoefficientswere obtained

wereanalyzedinconjunctionthroughmultivariateanalysis.

Table1–Clinicaldemographiccharacteristics.

NLGroup (n)

NNLGroup (n)

p

Age(mean) 22,2 23,1 0,07

GenderM:H 47:11 82:58 0,004

Race(mulatto/white)(%) 52 132 0,9

BMI 21,7 23,4 0,001

Smoking(%) 15 38 0,99

Alcoholconsumption(%) 31 76 0,96

Druguse(%) 13 32 0,90

Physicalexercise(%) 10 43 0,07

StatisticalTest,chi-square.

A5%(p<0.05)levelofsignificancewasadoptedforallthe tests.

Results

Atotalof198youngadultswereexamined,129womenand 69 men,withanaverageageof22.9 years.Ofthisnumber, 193(97%)werewhiteormulatto(Table1).Fifty-eight

individ-ualswerediagnosedassufferingfromnonspecificchroniclow

backpain(groupNL),while140presentednosuchcondition

(groupNNL).TheVASaverageforgroupNLwas4.92.The

clini-caldemographiccharacteristicsofthetwogroupscanbeseen

inTable1.There wasadifferenceinpercentageoffemales

betweenthetwogroups(greaterinNL)andintermsofBMI

(higherinNNL).

ComparisonsbetweengroupsNLandNNLdidnotreveal

anystatisticallysignificantdifferencesinrelationtothe

pro-posedbehavioralriskfactors,suchassmoking,alcoholintake,

druguse,orphysicalexercise.However,therewasastatistical

trendassociatingtheabsenceofchroniclowbackpainwith

thepracticeofphysicalexercise(Table1).

However,wedidfindsignificantdifferencesbetweenthe

groups according tothe followingoutcomes, forgroupNL,

female (p<0.05); lower BMI(0.001) and previous history of

back pain (p=0.003);low scores on health self-assessment

(p<0.0001);familialhistory ofback pain(p=0.003);chronic

headaches (p=0.002); chronic use of analgesics (< 0.001);

diffusepain(p=0.025);VASfordiffusepain (p=0.01);

num-ber oftender points (p ≤ 0.001); morning stiffness in the

spine (p=0.02) and low quality of life according to SF-36

domains: physical functioning, body pain, general health,

vitality,socialfunctioning(p=0,01).Thoughnotstatistically

significant,therewasatendencytowardhigherqualityoflife

intherolephysicalandmental-healthdomainsoftheSF-36

(Tables1–4).

Thetestsanalyzedbylowerbackflexibility(toe-touchand

Schober)didnotrevealanystatisticallysignificantdifference

betweenthetwogroups(Table2).

Toassessthecorrelationbetweenpossibleriskfactorsand

the presenceofchronic lowback pain, aunivariate

analy-siswasdone.Somefactorsshowedastatisticallysignificant

correlationwiththepresenceoflowbackpain.Therewasa

negativecorrelationbetweenchroniclowbackpainandthe

followingvariables:BMI,health self-assessmentVAS,SF-36

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Table2–Outcomemeasuresrelatedtobackpain.

NLGroup (n=58)

NNLGroup (n=140)

p

Previousbackpain(%) 19 21 0,0008

Familialbackpain(%) 36 53 0,003

Schober’stestmean(± SD) 4,73(±1,24) 4,86(±2,17) 0,66

Toetouch(cm)mean(± SD) 10,3(± 11,3) 8,76(±9,55) 0,33

MorningStiffness(%) 25 9 0,02

VASbackpainmean(± SD) 4,92(2,03) 0 −

Analgesicsintake(%) 25 6 <0,0001

StatisticalTests:Student’sT;Quisquare

Table3–Outcomemeasuresrelatedtochronicpain.

NLGroup NNLGroup p

Diffusepain(%) 18 22 0,02

Headache(%) 23 25 0,002

VASdiffusepainmean(SD) 2,85(±3,13) 1,80(2,31) 0,01

Tenderpointsmean(SD) 4,81(±3,94) 1,91(± 2,55) <0,0001

Table4–Outcomemeasuresrelatedtogeneralhealth.

NLGroupn=58 NNLGroupn=140 p

Anxiety(%) 49 104 0,17

Sleepdisturbance(%) 23 42 0,25

Emotionalinstability(%) 8 21 0,99

VASgereralhealthmean(SD) 7,36(±1,72) 7,93(± 1,18) <0,0001

SF36Domaismean(SD)PhysicalFunctioning 84,9(±16,8) 92,20(±9,17) <0,0001

RolePhysical 78,8(± 26,6) 85,8(± 25,36) 0,084

BodyPain 59,6(± 17,3) 79,5(±17,6) <0,0001

GeneralHealth 66,12(± 20,16) 74,65(±15,20) 0,001

Vitality 52,36(± 18,07) 62,48(±18,20) <0,0001

SocialFunctioning 69,28(± 24,58) 80,24(± 21,53) 0,002

RoleEmotional 69,67(±38,69) 86,38(± 51,54) 0,22

MentalHealth 64,90(±18,87) 69,77(±16,06) 0,06

Table5–Nonspecificchroniclowbackpainassociatedfactors.Univariateandmultivariateanalysis.

univariate analysisCC

p multivariate

analysisCC

p

BMI 0,846 0,003

VAS:Healthselfevaluation 0,971 0,053

VAS:globalpain 1,18 0,005 0,732 0,006

Diffusepain 2,57 0,009

Tenderpoints 1,322 0,001 1,19 0,016

SF-36domains

Rolephysical 0,922 0.001

Socialfunctioning 0.981 0.003

BodyPain 0.945 <0.001

GeneralHealth 0.971 0.002

Vitality 0.981 0.001

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health,andvitality).Therewasapositivecorrelationwiththe

followingvariables:globalpainVAS,presenceofdiffusepain

andnumberoftenderpoints(Table5).

These variables, found to have statistically significant

correlations in univariateanalysis, were then subjected to

multivariateanalysis,whichdrewstatisticallysignificant

cor-relationsbetweenchroniclow backpainand the following

variables: global pain VAS and number of tender points

(Table5).

Discussion

Moststudiesonbackpainamongyoungeragegroupslargely

focusonsecondary-causeoccurrencesofthecondition,

espe-ciallythoserelatedtoinflammatorydiseases.5

Recentstudies haveshownthatbiomechanicaland

psy-chosocialfactorsalsoplayanimportantroleinthegenesisof

lowbackpainamongyoungandoldalike,mostofthemfocus

onchildrenandteenagers.20,23

However,itisveryimportanttostudytheyoung

popula-tion,becausetreatinglowbackpainduringthisphaseoflife

canbecrucialtopreventingtheseindividualsfromdeveloping

acutelumbagoatalaterstage.15

Thepresentstudyobservedthatassociationsexistbetween

chroniclowbackpainandthefollowingclinicaldemographic

variables:“femalegender”and“previoushistoryofbackpain”,

thuscorroboratingdataalreadyobtainedintheliteratureon

chroniclowbackpainamongadults.20,21

However,althoughourstudy foundahigher percentage

offamilial history of back pain for chronic low back pain

group,theliteraturedoesnotrevealanyassociationbetween

them.Nevertheless,informationobtainedfromthesubjects

dependson theirknowledgeoffamily backgrounds inthis

regard.

On the other hand, some recent papers have

sug-gestedapossibleassociationbetweenbackpainandgenetic

factors.22–25

We identified a positive statistical association between

chroniclowbackpainandotheroccurrencesofchronicpain,

suchasheadacheandthepresenceoftenderpoints,aswell

asindirectfindingsrelatedtopainingeneral,suchaschronic

useofanalgesics. Theassociationbetweenchronicpain of

differentoriginshasalreadybeendemonstratedinother

stud-ies,suggestinganimportantroleplayedbyneuromodulatory

aspectsintheonsetandperpetuationofchronicpain.26–28

Jonesetal.classifiedpotentialriskfactorsforlowbackpain

inchildrenand teens asper the following four categories:

anthropometricvariables,lifestylefactors,theoverburdening

ofjointsand psychosocial and behavioral factors.29 _Recent

studies have shown that psychosocial factors are strongly

relatedtoself-reportingoflowbackpainamongchildren.28–30

Somestudies conductedon adultshavefoundan

asso-ciationbetweencertainpainsyndromes,suchasbackpain,

pelvicpain,irritablebowelsyndromeandcomplaintsof

gen-eralizedpain.31–33_This_association_would_seem_to_be_related_to

thestimulationofthecentralnervoussystemthrough

periph-eralnociceptors.34,35 _In_addition_to_these, _central_inhibitory

and facilitating mechanisms are involved inthe spreading

ofpain, asare corticalandsubcortical processesrelatedto

chronicpain.36

Chronicpaincanalsoreflectnegativelyuponlifequality,

asdemonstratedbyourstudy,onwhichweidentifieda

corre-lationbetweenabadassessmentofaspectsofqualityoflife

(rolephysical,bodypain,generalhealth,vitalityandthesocial

functioning)andthepresenceoflowbackpain.

Asedentarylifestyleisconsideredalowbackpainrisk

fac-toramongthegeneralpopulation,butitisalsoknownthat

childrenandyouthswhodonotpracticephysicalexerciseare

farmorelikelytobecomesedentaryadults.37,38

However,somestudiesshowanassociationbetweenthe

practiceofcertainphysicalactivitiesandthedevelopmentof

lowbackpain.13–22_Studies_assessed_back_pain-related_risk

fac-torsamongyoungathletes,andthesewererelatedtocertain

structuralcauses,suchasdischerniationandspondylolysis,

brought on byexcessive stretching,flexing and rotationof

thespine,andoverburdeningoftheposteriorelementsofthe

spine,usuallythroughthehyperlordosisthataffectscertain

groupsofathletes,especiallygymnasts.13,39,40

In a25-year cohort study with childrenand teensaged

between12and17,theauthorsevaluatedthedevelopment

oflowbackpainduringthisperiodandconcludedthatthe

practiceofphysicalexercisereducestheriskofdeveloping

lowbackpain.41

In the present study,we identified a low percentageof

physicalexerciseamongthe NL group(17%).This

percent-agewashigherintheNNLgroup(30%),butwithoutstatistical

differencebetweenthem.Analyzedtogether,theoverall

per-centageofparticipantspracticingphysicalexercisewasonly

26%,whichmeansa74%rateofsedentary.

Another riskfactor knowntoberelated tothe

develop-ment oflowbackpaininteenagersand adultsissmoking.

Ina recentlypublishedmeta-analysis, theauthors founda

moderatecorrelationbetweenasmokinghabitandlowerback

paininadults.However,theauthorsfoundastronger

associ-ationbetweencurrentsmokingandtheincidenceoflowback

paininadolescentsthaninadults.42_In_our_study,_we_did_not

identifyastatisticallysignificantdifference between

smok-ersandnon-smokersinrelationtopaininthelumbarregion.

Thismaybeaccountedforbytheverylownumberofsmokers

ingroupNLincomparisonwithNNL.Thisdifferencemaybe

morepronouncedinalargersample.

Onourstudy,whenweransimplestatisticalcomparisons

betweenthebackpainsuffersandnon-sufferersinayoung

adultpopulation, weobservedsomefactors that showeda

clearassociation withlumbarpain, namelyfemale gender,

lower BMI, personalor family history of back pain,

morn-ingstiffnessinthelumbarspine,theuseofanalgesics,low

quality oflife,frequentheadaches,diffusepainand higher

numberoftenderpoints.Someofthesevariableshavebeen

citedpreviouslyinstudiesconductedonadults.However,the

associationbetweenlowerBMIandlumbarpainthatemerged

from oursample was quite surprising. Studies with larger

sampleswouldhavetobeconductedinordertoevaluatethis

association.

On the other hand, when we refined our statistical

analysis using univariate logistic regression, we observed

fewer variables vs. low back pain associations in group

(6)

life and variables linked with diffuse pain were corrobo-rated.

Aftermultivariatelogisticregressionanalysis, the

statis-ticallysignificantassociationsthat remainedwereahigher

scoreforgeneralizedordiffusepainandahighernumberof

tenderpoints.Inotherwords,ourresultswouldsuggestthat

youngadultswithchroniclowbackpainarethosewithamore

perceptionofdiffusepain.

Patientswithchronicdiffusepain,includingthose

suffer-ing from fibromyalgia, may present lumbarbackpain as a

symptom.Lowbackpaincanbeevenaninitialsymptomof

thisconditionincertaincases.31,32

In conclusion, the present study found correlations

betweenlower back painin youngadultsand some

possi-bleriskfactors,suchaschronicpain,lowqualityoflifeand

priorhistoryoflowbackpain.Inamultivariatelogistic

regres-sionanalysis,theassociationswiththechroniclowbackpain

groupthatremainedwereahigherscoreforgeneralizedor

dif-fusepainandahighernumberoftenderpoints.Asthiswas

atransversalsample,theresultsmustbeanalyzedwithcare,

astheidealstudytypebywhichtoidentifychroniclowback

painriskfactorswouldbeaprospectivecohortstudy,likethe

oneconductedbyMikkelssonetal.41

However,weconductedastudyinvolvingapopulationthat

isseldomstudiedwithregardtochroniclowbackpain,asmost

studiesconductedonyoungadultsfocusoninflammatory

dis-easesofthespine.

Futurelongitudinalstudiesarerequiredinorderto

evalu-atenonspecificbackpaininyouth,approachingepidemiology,

risk factors and chronification. Then it will be possible to

devisemorespecificandthereforemoreefficienttreatment

andpreventionstrategies.

Conflicts

of

interest

Theauthorsdeclarenoconflictsofinterest.

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