www.bjorl.org
Brazilian
Journal
of
OTORHINOLARYNGOLOGY
ORIGINAL
ARTICLE
Vocal
assessment
of
addicts
on
methadone
therapy
via
the
RBH
scale
and
objective
acoustic
parameters
夽
Veljko
Mirkov
a,
Slobodan
M.
Mitrovi´
c
a,b,∗ aUniversityofNoviSad,FacultyofMedicine,NoviSad,SerbiabClinicalCentreofVojvodina,OtorhinolaryngologyClinic,DepartmentofPhoniatrics,NoviSad,Serbia
Received5May2017;accepted16October2017 Availableonline10November2017
KEYWORDS Opiatesubstitution treatment; Voice; Acousticanalysis Abstract
Introduction:Alargenumberofpeoplearoundtheworldstruggledailytobecomefreeoftheir addictionto illegalpsychoactivesubstances. Inorderto createanatmosphereofimproved supervision,establishedcommunicationandimprovedqualityoflifefordrugaddicts,centers havebeensetuptoprovidemethadoneasasubstitute.
Objective:The aim of the research was to assess the vocal features of drug addicts on methadonetherapyviasubjectiveandobjectiveparameters,toascertainifvocaldamagehas occurredandtodeterminewhethersubjectiveandobjectiveacousticvocalparametersare related,andhow.
Methods:Theresearchincluded34adultsofbothgenderswhowereundergoingmethadone treatment.Asubjectivevocalevaluationassessedvoicepitchandclarity,whilethesubjective acousticanalysisutilizedtheRoughness-Breathiness-Hoarsenessscaleof roughness-breathiness-hoarseness. Objective acoustic analysis was conducted after recording and analyzing an uninterrupted vocal /a/ of at least three seconds duration, using the ‘‘GllotisController’’ software.
Results:The subjective acoustic analysis using the Roughness-Breathiness-Hoarseness scale showedpathologicalvaluesin52.9%maleand47%femaleparticipants.Theaveragevaluesof theroughness-breathiness-hoarsenessfortheentiresamplewere0.91,0.38and0.50, respec-tively.Lowerroughnesswasassociatedwithahigherfundamentalfrequency(f0)andlowerjitter
andshimmervalues(p<0.05).Therewasastatisticallysignificantcorrelationbetween breath-iness,jitter(p<0.01)andshimmer(p<0.05),andbetweenhoarsenessandjitter(p<0.01). Conclusion:Astatisticallysignificantcorrelationwasfoundbetweenthetwosubjectivevocal assessments, voice clarity and pitch,and Roughness-Breathiness-Hoarseness scale, and the parametersoftheobjectiveacousticvocalassessment.
夽 Pleasecitethisarticleas:MirkovV,Mitrovi´cSM.VocalassessmentofaddictsonmethadonetherapyviatheRBHscaleandobjective acousticparameters.BrazJOtorhinolaryngol.2019;85:50---4.
∗Correspondingauthor.
E-mail:slobodan.mitrovic@mf.uns.ac.rs(S.M.Mitrovi´c).
PeerReviewundertheresponsibilityofAssociac¸ãoBrasileiradeOtorrinolaringologiaeCirurgiaCérvico-Facial.
https://doi.org/10.1016/j.bjorl.2017.10.008
1808-8694/©2017Associac¸˜aoBrasileiradeOtorrinolaringologiaeCirurgiaC´ervico-Facial.PublishedbyElsevierEditoraLtda.Thisisanopen accessarticleundertheCCBYlicense(http://creativecommons.org/licenses/by/4.0/).
© 2017 Associac¸˜ao Brasileira de Otorrinolaringologia e Cirurgia C´ervico-Facial. Published by Elsevier Editora Ltda. This is an open access article under the CC BY license (http:// creativecommons.org/licenses/by/4.0/). PALAVRAS-CHAVE Tratamentode substituic¸ãode opiáceos; Voz; Análiseacústica
Avaliac¸ãodavozdedrogaditosemterapiacommetadonaatravésdaescalade rugosidade,soprosidadeeaspereza,eparâmetrosacústicosobjetivos
Resumo
Introduc¸ão: Umgrandenúmerodepessoasemtodoomundolutadiariamenteparalivrar-sede seuvícioemsubstânciaspsicoativasilegais.Comoobjetivodecriarumaatmosferade super-visãomelhorada,comunicac¸ãoestabelecidaemelhoradaqualidadedevidaparadrogaditos, foramcriadoscentrosquefornecemasubstânciasubstitutivametadona.
Objetivo: Avaliaravozdedrogaditosquerecebemterapiacommetadonaatravésde parâmet-rossubjetivoseobjetivos,paradeterminaroeventualdanoàvoz,bemcomodeterminarseos parâmetrosvocaisacústicossubjetivoseobjetivosestãointerligadosecomoissoocorre. Método: A pesquisaincluiu 34 participantes,usuários de terapiacom metadona,de ambos ossexos.Aavaliac¸ãovocalsubjetivaconsistiunaavaliac¸ãodotom(pitch)eclarezadavoz, enquantoaanáliseacústicasubjetivaconsistiunousodaescalaRSA,derugosidade,soprosidade easpereza.Aanáliseacústicaobjetivafoirealizadaapósagravac¸ãoeanálisedavocalizac¸ão ininterruptade/a/comdurac¸ãodenomínimotrêssegundos,comosoftwareGllotisController. Resultados: AanáliseacústicasubjetivautilizandoaescalaRSAmostrouvalorespatológicosem 52,9%dehomense47%emmulheres.Osvaloresmédiosdosparâmetrosrugosidade, soprosi-dadeeasperezaparatodaaamostraforam0,91,0,38e0,50,respectivamente.Oparâmetro rugosidademaisbaixoesteve associadoavalores maisaltosdefrequênciafundamental(f0) emenorjittereoshimmer(p<0,05).Entreoparâmetrosoprosidadeeojitter(p<0,01)e oshimmer(p<0,05)houveumacorrelac¸ãoestatisticamentesignificante,bemcomoentreo parâmetroasperezaeojitter(p<0,01).
Conclusão:Foiencontradaumacorrelac¸ãoestatisticamentesignificanteentreaavaliac¸ãovocal subjetiva daclareza e do tom (pitch) da voz eos parâmetros da avaliac¸ão vocal acústica objetiva,bemcomoosparâmetrosdaanálisevocalacústicasubjetivautilizandoaescalade rugosidade,soprosidadeeasperezaeosparâmetrosacústicosobjetivos.
© 2017 Associac¸˜ao Brasileira de Otorrinolaringologia e Cirurgia C´ervico-Facial. Publicado por Elsevier Editora Ltda. Este ´e um artigo Open Access sob uma licenc¸a CC BY (http:// creativecommons.org/licenses/by/4.0/).
Introduction
A large number of people worldwide try every day to rid themselves of their addiction to illegal psychoactive substances. It is essential to make a distinctionbetween theterms ‘‘physical’’and‘‘psychological’’addiction.The signs of physical addiction are: manifesting symptoms of withdrawal during reduced or discontinued substance use, as well as the manifestation of tolerance due to continuedsubstanceuse.Psychologicaladdictionis charac-terizedbyapersistent,ubiquitousandpowerfuldesirefor repeatedsubstanceuse,withoutthemanifestationof phys-icaladdiction.1
A special form of a health-medical treatment which authenticallyconfrontsthe problemofopiate addictionis calledsubstitutionaltherapy.Withthepurposeofcreating an atmosphere of improved supervision, smoothly estab-lishedcommunicationandimprovedlifequalityforaddicts, centerssuppliedwiththesubstitutionsubstancemethadone weredeveloped.
Methadoneisalipophilicandhighlyprotein-bound syn-thetic opioid with agonistic effect. It has a 50---80% oral bioavailabilityandahalf-lifeof72h.Methadonehasbeen usedincreasingly for neuropathic painas well asfor opi-oidtoleranceandopioid-inducedhyperalgesia.2Methadone
is a highly effective medication for opioid addiction and methadone maintenance treatment has been found to improvehealth status and promote accessto health care amongdrugusers.3
The medial orbitofrontal cortex is a part of the lim-bicsystem,andisafunctionallyheterogeneousregionthat involved in complex adaptive behaviors: vocal expression of anger, fear, disgust, happiness, sadness and surprise.4
Its activities was observed in cocaine abusers. Medial orbitofrontal cortex and the frontal cingulate gyrus were importantareasidentifiedintheprocessofaddiction devel-opment;rightcaudateandrightcerebellarareasalsohave been identified as important in relapsed heroin addicts.5
Simultaneousnicotineandalcoholusecouldbeduetothe effectonthemesolimbicdopaminesystemwhichreinforces andrewardseverybehavior,andeachhasatolerancetothe
other,which,combinedwithcommongeneticfactors,leads toapredispositiontoaddiction.6
Methods
Researchwasconductedinaccordancewiththestatelaws. Approval of Ethics committee was not necessary when studywasconducted.Theresearchincluded34participants (17women and 17 men) whowere undertreatment with methadonetherapy.Aquestionnairewasusedtocollect gen-eraldata,informationaboutthedurationofthemethadone therapy,whichdrugwasconsumedandhowinthepatient’s life,andwhetherandwhichvocaldifficultieshadbeen expe-rienced.Asubjectivevocal assessmentassessedtwotypes of parameters: first, the assessment of pitch and clarity ofvoice,andsecond,asubjectiveacousticanalysis involv-ingtheuseoftheRBH(Roughness-Breathiness-Hoarseness) scale. The participants read numbers from 1 to 10 and the analysis was conducted by two educated listeners (phoniatrist and logopedist). Objective acoustic analysis was conducted after recording and analyzing an uninter-ruptedvocal /a/ofat leastthreesecondsduration,using the‘‘GllotisController’’ software.7 A‘‘ShurePG48-XLR-B’’
microphonewasusedforrecording.Basicfrequency param-eterswereanalyzed---f0,jitterandshimmer.Thestatistical
packageIBMSPSS20.0wasusedforthestatisticalanalysis ofdata.
Theaimoftheresearchwastoassessthevoiceofaddicts onmethadonetherapywithsubjectiveandobjective param-eters,todetermineeventualvoicedamageifitexistsaswell astodeterminewhethersubjectiveandobjectiveacoustic vocalparametersareconnected,andhow.
Results
The average age of the 34 participants was a little over 35.5years.Themajorityofparticipantsreceivedmethadone therapy for longer than 18months, only one participant receivedmethadonetherapyforbetween12and18months, whiletwoparticipantsreceivedtherapyforbetween6and 12months.Noparticipantsreceivedtherapyforlessthan6 months.
Beforeinitiationofthemethadonetherapy,themajority ofthesubjectsreportedhavingnopreviousdifficultieswith theirvoice(82.4%),2.9%ofparticipantsexperiencedvocal difficulties,while 14.7% ofparticipants experienced vocal difficultiesoccasionally.
According to the subjective vocal pitch assessment, 38.2%ofthesampleshowedappropriatepitch,5.9%hadan elevated pitch,while 55.9% had a lowervocal pitch. The subjectiveassessmentofvocal clarityrevealedthat52.9% ofparticipantshada clearvoice,while 47.1%showedthe presenceofpathologicalpsychoacousticphenomenaintheir voice. These phenomena were analyzed using subjective acousticanalysis---RBHscale,andshowedpathological val-uesin9(52.9%)maleand8(47%)femaleparticipants.The averagevaluesoftheRBHparametersfortheentiresample were0.91, 0.38and 0.50 for theR, BandH parameters, respectively.
Objective acoustic analysis of fundamental frequency showedthattheaveragefrequenciesofparticipantsofboth
genderscorrespond withthe norms. Anindependent sam-plest-testdeterminedastatisticallysignificantdifferencein frequencies,whichwasexpectedasagenderspecifictrait. Thejitter parametervalues werefound nottodeviate from the established norms, i.e. the average values are withinthemarginsofnormalityforparticipantsofboth gen-ders. The average valuesof theshimmerparameter were foundtobewithinthenormallimitsinmen,andpathological inwomen(2.69±2.98;pathologicalvalue>2.5%).
The Pearson correlation coefficient shows a statisti-cally significant correlation between the subjective vocal pitch assessment and the f0 parameter. A voice
subjec-tively assessed to be of a higher pitch correlates with higherfrequencyintheobjectiveacousticvoiceanalysis.A statisticallysignificant correlation wasfoundbetween the subjective assessment of voice clarity and the jitter and shimmer parameters (p<0.01 for both parameters). The morepathologicalpsychoacoustic phenomenasubjectively noted to be present in the voice were higher jitter and shimmerparameters.
Spearman’scorrelationcoefficientprovidedresults sug-gesting a statistically significant correlation between the subjective voiceassessment and vocal roughness (param-eter R). Increased roughness was connected to a lower pitch (p<0.05). A statistically significant correlation was foundbetweenthesubjectiveacousticvocalassessmentand vocal breathiness (parameter B). Higher breathiness was related to a lower pitch (p<0.01). There was a statisti-callysignificantcorrelationbetweenthesubjectiveacoustic assessment and vocal hoarseness (parameter H). Higher hoarseness corresponded to a lower pitch (p<0.01) and lowervoiceclarity.
ThePearsoncorrelationcoefficientshowedastatistically significantcorrelationbetweenvocalroughness(parameter R)andobjectiveacousticvocalanalysisparameters.Lower vocalroughnesswascorrelatedwithahigherfrequency(f0)
andlowerjitter andshimmerparameter values(p<0.05). Statistically significantcorrelation wasidentified between vocal breathiness(parameterB)andshort-termfrequency (jitter)(p<0.01)andamplitude(shimmer)(p<0.05) varia-tions. Therewasalso astatisticallysignificant correlation between vocal hoarseness (parameter H) and short-term frequencyvariations(jitter)(p<0.01)(higherhoarseness ---higherjittervalues).
Discussion
The positiveeffectof themethadonesubstitutiontherapy allowsahigherqualityofsociallifeandadevelopmentof healthierpatternsofinterpersonalinteraction.Thechanges areevidentinthebehavioralsphereaswell,inareduction ofmisdemeanor.Inregardstosubstanceabuse,thepatient’s needsaretakencareof ona dailybasis,eliminatingrisky behavior involved in the acquiring andpurchasing of ille-gal substances.The majority of methadonetherapy users areaddictsfor manyyearswhohave difficultycompletely quittingtheopiate.8
A voice with pathological characteristics can be a consequenceofchronicpsychoactivesubstanceabuse.9
Mar-ihuanaconsumptionisacommoncauseofvocalhoarseness, roughnessanddifficultieswithpitchchange.10 Asubstance
ofthepsychostimulantgroup,cocaine,causes vasoconstric-tion,whichleadstodecreasedvocalcontrolanddysphonia manifestation in users.11,12 Certain studies suggest a link
betweenpoorqualityoflifeandvocaldisorderscausedby psychoactive substance use. According to Byeon & Lee,6
commonuseofcentralnervoussystemdepressors(alcohol) causes dysphonia, while the use of tobacco or the simul-taneous use of tobacco and alcohol increases the risk of laryngealandvocalpathology.
Areviewofliteraturerevealedthatresearchonthetopic ofaconnectionbetweenacousticvocalcharacteristicsand thedurationofprescribedmethadonetherapyhadnotbeen reported.
Otolaryngological examinations of addicts, especially thoseconsumingdrugsbysnorting,arenecessaryinaddition toconsideringalldifficultiestheseaddictsmayexperience. TheresearchofNasifFilhoandcolleagues12 foundthatthe
following symptoms were observed in the ORL sphere of addictsusingcocaineand/or crack:throatsoreness,nasal obstruction,rhinorrhea,coughing,thesensationofaforeign body in the pharynx (globus pharyngeus), nasal hemor-rhages,andthelossofsmellandtaste.Dysphoniawasfound in50%ofparticipants.
Prolongedpsychoactivesubstanceuseresultsinorganic andfunctionallaryngealchanges.Besidesinflammationand pseudo-tumors(Reinke’sedema,polyps,nodes),malignant changes can alsooccur onthe vocal chords. Tobacco and alcohol areco-carcinogenicfor thedevelopmentof laryn-gealcancer. Marihuanauseis alsoresponsiblefora direct association between cannabis smoking and increased risk of laryngeal cancer. Marihuana may cause vocal edema, but in addition to causing vocal disorders, also leads to articulation,rhythmandfluencydisorders.Cocainereduced auditorycontrolandcausesvocalabuse.6,11---13
Byeon and Lee6 conducted a research on participants
agedfrom65to84whoconsumecigarettesandalcoholand investigatedtheirconnection withtheformation of laryn-geal pathology.Participants were of differenteducational profiles and professions.The authors concludedthat 8.1% ofatotalof663participantshadlaryngealpathology.Also, theyobservedmoreinstancesoflaryngeallesionsinsmokers thanin non-smokers, while current alcoholconsummation showed no connection to laryngeal pathology. However, simultaneous consummation of tobacco and alcohol coin-cided with a significantly higher occurrence of dysphonia andtheriskofdevelopingpathologyofthelarynx.
Moreira andcolleagues14 conductedresearchsimilarto
the one presented in this paper (Table 1). The partici-pants of their study were psychoactive substances users. Forthesubjectiveacousticvoiceanalysis,subjectscounted from 1 to 20, and the results were presented using the GRBAS(Grade-Roghness-Breathiness-Astenity-Strain)scale. For the objective acoustic analysis, the VoxMetria soft-ware was used, and the f0, jitter, shimmer and glottal
noise excitation parameters were assessed. They had a similar number of participants --- 29, while the present studyhadsomewhatmore,34.Theresearcherslinkedthe presenceofpathologicalpsychoacousticphenomenainthe voicewiththeperceptualauditory phenomena,aswellas potential organic changes, especially in patients consum-ingalcoholandcigarettes.Eventhoughnodifferenceswere foundbetweenthegroupsinregardstoobjectiveacoustic
parameters,theseauthorsbelievethattheincreaseinjitter canbeconnectedtoa decreaseof motorcontrol of mus-clesengagedinphonation.Theshimmerparametercanbe relatedtoadecreaseinglottalresistance,thepresenceofa massonthevocalchordsoranirregularvocalcontact(vocal insufficiency).
The subjective acoustic vocal analysis of voice clarity foundthat47.1%ofparticipantshadpathological psychoa-cousticphenomenapresentintheirvoice.Thesephenomena wereanalyzed withRBH scale. Ajustification for the use oftheRBHscaleinthepsychoacousticvocalassessmentof dysphonicpatientswasgivenbyLietal.15Judging100
dys-phonicpatientstheyreported goodinter-rateragreement and intra-rater reliability. The differences of the acous-ticparameters between adjacent ranksin the perceptual parameters(R,B,H)weresignificant(p<0.05).The percep-tualparameters(R,B,H)weresignificantlycorrelatedwith theacousticparameters(jitter,shimmer,andother,) with
p<0.01.TheyconcludedthatreliabilityofRBHperceptual evaluationsystemisgoodandhasbroadprospectsinclinic practice.
Ptok et al.16 investigated inter-rater reliability of the
auditoryperceptualassessmentofvoicequality.Validityand intra-raterreliabilitywerenotconsidered.Afterreadingof standardtextby78patients,19speechandvoicetherapy studentsanalyzedtheirvoicewithRBHscale. Theauthors concludedthattheapplicationoftheRBHscalewassuitable forclinicalpurposes.
Results of thepresent study indicatemostly preserved objectiveacousticvocalparameters,specificallyf0whichis
withinthenormalvaluerangeforbothmenandwomen,as isthejitterparameter.The differencesfoundwereinthe shimmerparameter,whichhadapathologicalaveragevalue inwomen,andanormalaveragevalueinmen.
Eventhough f0valueswerefoundtobenormalinboth
maleandfemaleparticipants,thereweremoreparticipants withloweredvocalpitchinthesubjectiveacousticanalysis, whiletheobjectiveacousticanalysisresultsshowedvalues closertolowaveragelevels,notablyinfemaleparticipants. Consideringallparticipantsusedvariousdrugsandin var-iousways, itisnotpossible tolink aspecifictypeofdrug andmethodof use withtheresults of thesubjective and objectiveacousticvocalanalyses.
Eventhoughnearlyahalfofparticipantsmanifested sub-jectivepsychoacoustic pathologicalvocal phenomena,and hadundergoneprolongedmethadonetherapy(91.2%longer than18months),itisnotpossibletospeculateabouttherole ofmethadoneinthestabilizationofthephonationfunction insubstanceusers.
Conclusion
Objectiveacousticanalysis fundamental frequency of the voiceofmethadone addictsshowed thatthe average fre-quenciescorrespondtonormativedataandthestatistically significantdifferenceinfrequencies betweengenders was expectedas a gender specific trait. The jitter parameter valuesdidnotdeviatefromtheestablishednormsnordid averagevaluesoftheshimmerparameterinmen,although theywereabnormalinwomen.
Table1 ThecomparisonofvaluesofobjectiveacousticassessmentparametersfoundinthestudiesofMoreiraandMirkov& Mitrovi´c.
Legalandillegalsubstanceusers Moreira Methadonetherapyusers Mirkov&Mitrovi´c Numberofparticipants 29 Numberofparticipants 34
Averagef0valuemen 136.37Hz Averagef0valuemen 104.49Hz
Averagef0valuewomen 190.99Hz Averagef0valuewomen 167.24Hz
Averagevalue--- jitter 0.33% Averagevalue---jitter
Men 0.62%
Women 0.54%
Averagevalue---shimmer 6.16% Averagevalue---shimmer
Men 2.86%
Women 2.69%
Inour studysample of methadoneaddicts,almost half exhibitedpathologicalpsychoacoustic phenomenain their voices and almost half of the males and females showed pathologicalvaluesoftheRBHscaleparameters.
Astatisticallysignificantcorrelationwasfoundbetween thesubjectivevocal assessment ofvoiceclarityand pitch andtheparametersoftheobjectiveacousticvocal assess-ment. There was also a significant correlation between the parameters of the subjective acoustic vocal analysis using the RBH scale and the objective acoustic parame-ters.Increasedvocal roughness(parameterR)wasrelated to a lower pitch and lower pitch is also correlated with higherfrequency(f0)andlowerjitterandshimmer
param-eter values. Higher breathiness (parameter B) correlated withalowerpitch,aswellasshort-termfrequency(jitter) andamplitude (shimmer) variations. Higher vocal hoarse-ness(parameterH)wasrelatedtoalowerpitchandlower voiceclarity.Ifhoarsenesswashigher,jittervalueswerealso statisticallysignificanthigher.
Conflicts
of
interest
Theauthorsdeclarenoconflictsofinterest.
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