Anxiety, depression and quality of life (QoL) in patients with chronic dizziness

Anxiety,

depression

and

quality

of

life

(QoL)

in

patients

with

chronic

dizziness

Yuan-Yang

Cheng

,

Chia-Hua

Kuo

,

Wan-Ling

Hsieh

,

Shin-Da

Lee

,

Wei-Ju

Lee

,

Liang-Kung

Chen

,

Chung-Lan

Kao

*

a

DepartmentofPhysicalMedicine&Rehabilitation,Yuan-ShanVeteransHospital,No.386,RongguangRd.,YuanshanTownship,YilanCounty264,Taiwan,ROC

b

LaboratoryofExerciseBiochemistry,TaipeiPhysicalEducationCollege,No.101,Section2,Jhong-ChengRoad,Taipei111,Taiwan,ROC

c

DepartmentofPhysicalMedicine&Rehabilitation,TaipeiVeteransGeneralHospital,No.201,Section2,Shih-PaiRoad,TaipeiCity112,Taiwan,ROC

d_{CenterforGeriatricsandGerontology,TaipeiVeteransGeneralHospital,No.201,Section2,Shih-PaiRoad,TaipeiCity112,Taiwan,ROC}

e_{DepartmentofPhysicalTherapy,GraduateInstituteofRehabilitationScience,ChinaMedicalUniversity,Taichung,91Hsueh-ShihRoad,Taichung402,Taiwan,ROC} f

DepartmentofFamilyMedicine,Yuan-ShanVeteransHospital,No.386,RongguangRd.,YuanshanTownship,YilanCounty264,Taiwan,ROC

g

NationalYang-MingUniversity,SchoolofMedicine,No.155,Sec.2,LinongSt.,BeitouDist.,TaipeiCity112,Taiwan,ROC

1. Introduction

1.1. Dizzinessandmooddisorders

Patientswithdizzinessoftensufferfromanxietyand depres-sion,and patients withthese mooddisorders often experience subjectivedizziness (JacobandFurman, 2001).Previous studies have showna direct connectionbetween vestibularnuclei and brainstemregions,includingthelimbicsystem,andanystimuli thataffectbalancecontrolcanhaveasignificantinfluenceonthe ascending pathway,which is associated withanxiety(Balaban, 2002).Ontheotherhand,emotionalfactorscanaffectbalanceand motorcontrolstrategiesinvestibularpatientsduetotheirfearof falling (Shumway-Cook and Horak, 1988). Therefore, normal motor compensation is hindered, and the handicap due to dizziness is exacerbated. Patients with dizziness often restrict their dailyactivities.Duetounpleasant long-termmemoriesof instabilityandfearoffallingarisingfromdizzinessattacks,these patientsoften developavoidancebehaviors.Theytendtoavoid environmentsthat increase their spatial disorientation suchas

grocerystoresandparkinglots,andavoidactivitiesinvolvinghead movements; they are also unwilling to go outdoors without assistance.Theseavoidancebehaviorsresultinlimitedactivitiesof daily life and a subsequent declined life quality, leading to depressioninmanycases.

1.2. Dizzinessintheelderly

Dizzinessisacommonsymptominadults,andtheprevalence increases with age (Maarsingh et al., 2010). Due tothe rapidly increasing aging population around the world and the high prevalenceofdizzinessamongtheelderly,dizzinesshasgradually become a serious healthcareproblem in society.In the elderly, sensoryandproprioceptivefunctiondeclines,andmuscularatrophy alsofrequentlyoccurs.Chronicillnesses,suchasatherosclerosisand diabetesmellitus,affecttheperipheralvascularsystemandnervous system, which leads to additional balance problems. Therefore, psychological factors are less common as primary causes of dizzinessintheelderly(Sloaneetal.,1994).

1.3. Aimsofthisstudy

Thiscross-sectionalstudyfocusedonthecorrelationbetween thedegreeofhandicapand theseverityofmooddisordersina groupofdizzypatients.Furthermore,wearealsointerestedinthe difference between dizziness handicap severity and mood

A R T I C L E I N F O Articlehistory:

Received25November2010 Receivedinrevisedform6April2011 Accepted7April2011

Availableonline11May2011 Keywords:

Dizziness Anxiety Depression

A B S T R A C T

Mooddisordersandtheseverityofdizzinessofteninteractwitheachother.However,theimpactofage onanxietyanddepressionindizzypatientshasrarelybeenexplored.Thepurposeofthisstudywasto evaluatethecorrelationbetweentheDizzinessHandicapInventory(DHI)andtheHospitalAnxietyand DepressionScale(HADS)inagroupofpatientswithdizziness.Thestatisticalrelationshipsbetweenage and eachscale werestudied. This cross-sectional studyrevealed a highcorrelation betweenDHI subgroups and HADS subscales. We found statistical correlation between neither age and HADS subscalesnorageandDHIsubgroups.Inaddition,Short-Form36HealthSurveyQuestionnaires(SF-36) showedahighcorrelationwiththedizzinesshandicapseverity.Thepresentstudyrevealedthatagedoes notinfluencemooddisordersandtheseverityofdizzinessindizzypatients.

ß2011ElsevierIrelandLtd.Allrightsreserved.

*Correspondingauthorat:DepartmentofPhysicalMedicine&Rehabilitation, TaipeiVeteransGeneralHospital,No.201,Section2,Shih-PaiRoad,TaipeiCity112, Taiwan,ROC.Tel.:+886228757363;fax:+886228757359.

E-mailaddress:clkao@vghtpe.gov.tw(C.-L.Kao).

ContentslistsavailableatScienceDirect

Archives

of

Gerontology

and

Geriatrics

j ou rna l h om e pa ge : w w w. e l s e v i e r. co m/ l oc a t e / a rch ge r

0167-4943/$–seefrontmatterß2011ElsevierIrelandLtd.Allrightsreserved. doi:10.1016/j.archger.2011.04.007

disordersin olderand youngerdizzy patients. The influenceof dizzinessonthepatient’sQoLisalsodiscussed.

2. Subjectsandmethods 2.1. Theevaluationtools

Toevaluatetheseverityofdizzinessinpatients’dailylife,we adoptedtheDHIasourevaluationtool.TheDHIisavalidated, self-reported questionnaire which is widely used to evaluate the functional,emotionalandphysicalimpactofdizzinessonpatients’ dailylife(JacobsonandNewman,1990).Itconsistsof25questions aboutdailyproblemsassociatedwithdizziness,andeachquestion isgivenascoreof0,2,or4.Ascoreof0meansthatthecondition describedinthequestionneverhappens,2meansit sometimes happens,and4meansitalwayshappens.Accordingtothestudyby

Whitneyetal.(2004),theDHIscoresweregradedasmild(0–30 points),moderate(31–60points),andsevere(61–100points)in ourstudy.

The severity of mood disorders in dizzy patients was also evaluated, and The HADS was adopted. Although the term ‘‘hospital’’suggeststhatthescalemayonlybevalidinhospitalized patients,several studieshavevalidatedthescalein community settings(Snaith,2003).TheHADSconsistsof7questionsaboutthe anxietystatusand7aboutthedepressionstatus;eachquestionis givenascorefrom0to3accordingtothedegreetowhichpatients agreewiththequestion.Therefore,themaximumscoreforeach subscale is 21. Scores of 11 or more on either subscale are consideredtobeasignificantmorbidityofmooddisorder,whereas scoresof8–11representborderlinemorbidityand0–7isnormal. Inourstudy,wedefinedsubscalesscoresof7orbelowasbeing normal;andscoresof8oraboveasbeingabnormal.

TheSF-36isawidelyusedtoolforevaluatingaperson’shealth perceptionindailylife;theacceptability,validityandreliabilityof thisquestionnairehasbeenconfirmedinpreviousstudies(Brazier etal.,1992;Wangetal.,2008).TheSF-36consistsof36questions which are grouped into eight health categories as follows: (1) limitationsin physicalfunctionbecauseofhealth problems,(2) limitations in social function because of physical or emotional problems,(3)limitationsinusualroleactivitiesbecauseofphysical health problems, (4) bodily pain, (5) general mental health (psychologicaldistress and well-being),(6) limitations in usual roleactivitiesbecauseofemotionalproblems,(7)vitality(energy andfatigue),and(8)generalhealthperceptions.

2.2. Thestudyparticipants

FromAugust2007toFebruary2010,allpatientswithdizziness who presented to the outpatient clinic of the Department of PhysicalMedicine and Rehabilitation at a medical center were screenedby an experienced physiatrist for participationin the study.Thediagnosiswasmadebasedonthepatients’pastmedical history and physical examinations. Patients withthe following characteristicswereexcluded:a historyofpsychiatricdisorders diagnosedbypsychologists,suchasgeneralizedanxietydisorder (GAD)andmajordepression;medicationsthataffectvestibularor mentalfunctions;oranimpairedgeneralconditionduetoother majorhealthproblems.Atotalof85patientswereincludedinthe study,but6ofthemdidnotcompletethequestionnaires,which left 79 patients for statistical analysis. Table 1 provides the demographicdataofourstudyparticipants.

2.3. Dataanalysis

PASWStatistics 18.0(IBMCooperation2009)wasadoptedas ourstatisticaltool.TheFisher’sexacttestwasusedtoexaminethe

correlationbetweentheDHIsubgroupsandHADSsubscales,and theChi-squaretest wasusedtocomparethedatabetween the older(65yearsoldorabove)andyoungerpatients.Furthermore, one-wayANOVAwasusedtodetermine iftherewasstatistical significanceinthe8categoriesofSF-36scoresamongthedifferent levelsofDHI.

3. Results

3.1. ThecorrelationofHADSamongdifferentlevelsofDHI

Thestatistical resultsof theFisher’s exacttest areshownin

Table2.PatientswithhigherlevelsofDHIweremorepronetobe abnormal in both the HADS-anxiety scale and the HADS-depression scale, whereas patients with anxiety or depression disorders tendedtohavehigher scoreson theDHI. Inall cases p<0.01wasobserved.

3.2. TheHADSandDHIscoresbetweenolderandyoungerpatients Theaveragescoresontheanxietysubscaleinthepatientswho were65yearsoldorolderwas5.154.21,whichwaslessthanthe meanscoresofpatientswhowerebelow65yearsold,8.676.27. Themeanscoresonthedepressionsubscaleintheolderandyounger patientswere6.194.28and6.745.31,respectively.Notably,the meanDHIscoresintheoldergroupwas39.8924.46;whereasthe meanDHIscoresintheyoungergroupwashigherat44.5226.78. However, the result of the Chi-square testshowed no statistical significanceinboththeHADSandDHIbetweenolderandyounger dizzypatients.TheresultsareshowninTable3.

3.3. TheSF-36scoresamongdifferentlevelsofdizzinesshandicap Patientswithmoreseverelevelsofdizzinesshandicaptended to have lower SF-36 scores in all the eight domains, whereas patientswhoscoredhighontheSF-36tendedtoshowmildlevels

Table1

Thedemographicdata,n(%). Gender Male 44(55.7) Female 35(44.3) Age,meanS.D. 68.0015.64 Age>65 52(65.8) Age<65 27(34.2) Diagnosis Dizziness 15(19.0)

Unilateralvestibularhypofunction 24(30.4) Bilateralvestibularhypofunction 36(45.6) Benignparoxysmalpositionalvertigo 1(1.3)

Centralvertigo 1(1.3)

Meniere’sdisease 1(1.3)

Parkinsondisease 1(1.3)

Table2

ThecorrelationofHADSamongdifferentlevelsofdizzinesshandicap,n(%). DHIhandicap

Mild Moderate Severe p

HADS-anxietyscale Normal 28(52.8) 19(35.8) 6(11.3) <0.01 Abnormal 4(15.4) 5(19.2) 17(65.4) HADS-depressionscale Normal 30(57.7) 12(23.1) 10(19.2) <0.01 Abnormal 2(7.4) 12(44.4) 13(48.1) HADS-totalscore Normal 27(60.0) 12(26.7) 6(13.3) <0.01 Abnormal 5(14.7) 12(35.3) 17(50.5)

ofdizzinesshandicap.Thestatisticalresultsoftheone-wayANOVA areshown inFigs. 1 and2.AlmostalltheSF-36 scoresamong differentlevelsofdizzinesshandicapwerestatisticallydifferent, except the scores between the mild and moderate levels of handicap in the domains of bodily pain, general health, role limitationduetoemotionalproblems,andmentalhealth. 4. Discussion

4.1. Thecorrelationbetweentheseverityofmooddisordersand dizzinesshandicap

Thisstudyprovidesinformationaboutthecorrelationbetween mooddisorders,dizziness severity, andagein a groupofdizzy patients. Several previous studies have shown the relationship between mood disorders and dizziness. Wiltink et al. (2009)

demonstratedanincreasedsubjectiveimpairmentandhealthcare utilizationinagroupofdizzinesspatientwithcomorbidanxiety.

Eckhardt-Hennetal.(2003)alsodiscoveredthatdizzinesspatients with anxiety and depressive disorders showed the greatest emotionaldistressandhandicaps.StaabandRuckenstein(2003)

discovered an almost equal prevalence among the following 3 conditionsintheirpatients:anxietydisordersasthesolecauseof dizziness, neurotologic conditions that exacerbate preexisting psychiatricdisorders,andneurotologicconditionsthattriggernew anxietyor depressivedisorders. However, theyalso foundthat depressionwasnota primarycauseofdizzinessinanyoftheir patients. Inourstudy,although wedidnot determinewhether dizzinessormooddisorderswastheprimarycause,patientswith higherscoresontheHADStendedtobemorehandicappedasa resultoftheirdizziness,whichiscompatiblewithpreviousstudies.

4.2. Theeffectofageonanxietylevelindizzypatients

Previous epidemiological studies on the general population foundthatanxietydisordersarelessprevalentinolderadultsthan inyoungeradults(Andrewsetal.,2001;Kessleretal.,2005;Wells etal.,2006).Thepeakageofonsetisinearlyadulthood,andthe prevalence and incidence decline in later life (Flint, 1997). However, someauthorschallengedthesefindings(Koganetal., 2000;O’Connor,2006).Theyproposedthattheunderestimationof anxietydisordersexistedintheelderlygroup,andtheysuggested thefollowingreasonsforsuchanunderestimation:reluctanceof olderpeopletoreporttheiremotionaland psychological symp-toms,areducedsensitivityofthesurveyinstrumentsusedinolder people,andarecallbiasintheelderly.Inourstudy,wefoundthat themeananxietyscoresoftheelderlygroupwaslessthanthoseof theyoungergroup.Thisfindingiscompatiblewiththe epidemio-logicalprevalenceofanxietydisordersinthegeneralpopulation, althoughstatisticalsignificancewasnotachieved.Thereasonsfor the difference between the general population and the dizzy patients in ourstudy can be divided into the mental and the physicalaspects.Inthementalaspect,theolderpeoplewhowere willingtoreporttheirdizzinessproblemsmayalsobewillingto reporttheirseverityofanxiety.Becausetheyaremorewillingto expresstheirphysicalsufferings,theiranxietyprevalencewasnot aslowasintheelderlyinthegeneralpopulation.Inthephysical aspect, duetodeterioratedproprioception, impairedvision, and muscular atrophy, the older people are prone to fall. When dizzinessiscomplicatedwithpreexistingproblems,theanxietyfor fall increases. The two reasons might explain why anxiety disorders are not significantly less prevalent in the elderly comparedtothegeneralpopulation.

4.3. Theeffectofageondepressionlevelindizzinesspatients Depressionisamooddisorderthatismoreprevalent among older people; prevalence in the elderly is three times the prevalence in the rest of population (Blazer, 2002). There are manyreasonsforoldpeopletodevelopdepressiondisorders,such asretirement,lossofprevioussocialstatus,bereavementoffamily members, social isolation, and worsening economic conditions. However,inareportbyRobertsetal.(1997),itwasrevealedthat thereisnogreaterriskforthedepressionintheelderlycompared to younger people, except those who have physical health problemsandrelateddisability.Thatmeanstheriskofdepression shouldbethesameiftheelderlydonotsufferfromagerelated

Table3

ComparisonoftheHADSandDHIbetweenseniorandyoungagegroups,n(%).

Age>65 Age<65 p HADS-anxietyscale Normal 38(71.7) 15(28.3) Abnormal 14(53.8) 12(46.2) 0.094 HADS-depressionscale Normal 36(69.2) 16(30.8) Abnormal 16(59.3) 11(40.7) 0.261

DHIscalehandicap

Mild 21(65.6) 11(34.4)

Moderate 18(75.0) 6(25.0) 0.410

Severe 13(56.5) 10(43.5)

Fig.1.ScoresofSF-36physicalhealthdomainsamongdifferentlevelsofdizziness handicap.*p<0.05;a

PF:physicalfunctioning;b

RP:rolelimitationduetophysical problem;c

BP:bodilypain;d

GH:generalhealth.

Fig.2.ScoresofSF-36MHdomainsamongdifferentlevelsofdizzinesshandicap. *p<0.05;a

VT:vitality;b

SF:socialfunctioning;c

RE:rolelimitationduetoemotional problem;d

diseases. In our study, we reported nearly identical mean depressionscoresbetweenolderandyoungerdizzypatientswith nostatisticallysignificantofdifference.Thisfindingiscompatible withtheresultsof Robertsetal. (1997).Because patients with majordiseasesorphysicalhandicapwereexcludedfromourstudy, thesinglemostcommonproblemintheolderandyoungergroups wasdizziness.Theresultofourstudyrevealedthattherewasno statistically significant difference in the severity of dizziness between the older and younger patients. Therefore, no more physicalhealthproblemsexistedintheelderlythanintheyounger patientsin ourparticipants, and therefore,no difference in the prevalenceofdepressionwasobservedinourstudy.

4.4. Theeffectofageonthehandicaplevelindizzinesspatients Duetothephysicaldegenerationofolderpeople,ahigherlevel ofhandicapduetodizzinessispredicted.Inourstudy,therewasno statisticallysignificantdifferencebetweentheolderandyounger patients.ThisfindingiscompatiblewiththestudybyArdicetal.

(2006). Due to impaired vision, proprioception and muscle

strengthinthelowerextremities,theelderlytendtohavepoorer functional balance abilities compared to the younger patients. However,a comparativestudybyRobertsonandIreland (1995)

revealed that the functional balance abilities could not be correlated withpatient handicap due to dizziness. The anxiety level and the coping strategies for dizziness may bethe more importantfactorinthedizzinesshandicap.Anxietydisordersare lessprevalentintheelderlythaninthegeneralpopulation,which couldexplain,atleastinpart,whythehandicaplevelisnothigher inolderpeoplewithdizziness.

4.5. TheimpactofdizzinessseverityonQoL

Patientswithmoreseveredizzinesstendtohavepoorerquality oflife(GrimbyandRosenhall,1995;EnloeandShields,1997).In ourstudy,a statisticallysignificantdifference existsamong the threelevelsofdizzinesshandicapinthefollowingfourdomains: physical functioning, role limitation due to physical problems, socialfunctioning,andvitality.Theresultsofourstudyaresimilar tothosein theFielder etal. (1996) study,which revealedthat vertigo sufferershad significant role limitationdue tophysical problemsandsocialfunctioninginmenandphysicalfunctioning andvitalityinwomen.EnloeandShields(1997)measuredthe SF-36scoresin95patientswithvestibulardisorders(meanage57 years)and foundlowerscoresinallsubscales,especiallyin the ‘‘rolelimitationduetophysicalproblems’’domain.Coincidentally, thoseauthorshaveconductedacorrelationstudybetweenthe SF-36subdomainsandtheDHIscores,andthefourlowestcorrelation domainsareasfollows:bodilypain,generalhealth,rolelimitation duetoemotionalproblemsandmentalhealth,whichareidentical toourstudy.

The reason that the four domains do not reach statistical significancebetweenmildandmoderatedizzinesshandicaplevel inourstudymightbecomeapparentafterreviewingthequestions. Inthe‘‘bodilypain’’domain,thequestion,‘‘Howmuchbodilypain have you had during the past 4 weeks?’’ may not have corresponding questions in the DHI. In the ‘‘general health’’ domain,statementssuchas‘‘Iseemtogetsickalittleeasierthan otherpeople’’and‘‘Iexpectmyhealthtogetworse’’havesimilar butnotequivalentquestionsintheDHI,suchas‘‘Becauseofyour problem,doyoufeelhandicapped?’’and‘‘Becauseofyourproblem, areyouafraidpeople maythinkyou areintoxicated?’’Thetwo questionnairesreflectdifferentaspectsofmental problemsthat areencounteredindailylife,whichmaybecomplementarytoone another(EnloeandShields,1997).Similarissuesareaddressedin SF-36questionssuchas‘‘Haveyoufeltdownheartedandblue?’’

and‘‘Didyoufeeltired?’’thatassessthe‘‘mentalhealth’’domain andquestionssuchas‘‘Duringthepast4weeks,haveyouhadany ofthefollowingproblemswithyourworkorotherregulardaily activitiesasaresultofanyemotionalproblems?’’thatassessthe ‘‘role limitation due to emotional problems’’ domain. The differences in the nature of these two questionnaires might explainthereasonforlackofsignificantdifferencebetweenthe mildandmoderatedizzinesshandicaplevelinthefourdomainsof SF-36inourstudy.However,thedifferencebetweenthemoderate andsevereDHIlevelswassignificantin all8domainsofSF-36, because all these questions were scored low when dizziness becamesevereenough.

4.6. Limitationofourstudy

There aresomelimitations inourstudy. First,patients with major psychiatric problems diagnosed by psychologists were excluded. Selection bias might exist because some people are hesitant to visit psychologists despite impaired mental health whilesearchingmedicalhelpfortheirdizziness.Second,patients withmajorhealthproblemswerealsoexcludedfromourstudy. Becausemajordiseaseismoreprevalentintheelderly,selection biasmightalsoexist.Finally,ourstudywascross-sectional,and someprematureinterferencesmightbenotdetected.

5. Conclusion

Ourfindingssuggestthatageisnotanimportantfactorinthe anxiety,depression,orseverityofdizzinessindizzypatients,ifthe influence of major health problems is excluded. Therefore, the therapeuticalgorithmshouldnotbedifferentbetweenolderand youngerpatients.Mooddisorders,severityofdizzinessand health-relatedqualityoflifearehighlycorrelated.Wesuggestthatmood disorders should be treated concurrently when a patient with severedizzinesssymptomsisencounteredinanoutpatientsetting, andhis/herfamilymembersshouldbeinformedofpossiblepoor life quality of this patient. When the complicating factors are ameliorated,thehandicapthatresultedfromdizzinesscouldthen belessened.

Conflictofintereststatement None.

Acknowledgements

ThisworkwassupportedbytheNationalScienceCouncil(NSC 96-2314-B-075-056-MY3, 99-2627-B-075-002), Veterans Affairs Commission(99-X2-8,GM100-X2-6),andYen-Tjing-LingMedical Foundation.

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