Social Support and Posttraumatic Stress Disorder a

SocialSupportandPosttraumaticStressDisorderamongFloodVictimsinHunan,ChinaSHUIDONGFENG,MPH,HONGZHUANTAN,PHD,ABUAKUBENJAMIN,MPH,SHIWUWEN,PHD,AIZHONGLIU,PHD,JIAZHOU,MPH,SHUOQILI,MD,TUBAOYANG,MPH,YANBOZHANG,PHD,XINHUALI,MB,ANDGANGQIANLI,MBPURPOSE:Toexploretherelationshipbetweensocialsupportandposttraumaticstressdisorder(PTSD)amongfloodvictims.METHODS:Across-sectionalsurveywascarriedoutin2000amongindividualswhohadsufferedfloodsin1998inHunan,China.Multistagesamplingwasusedtoselectthesubjectsfromtheflood-affectedareas.PTSDwasdiagnosedaccordingtoDSM-IVcriteria,andsocialsupportwasmeasuredaccordingtoasocialsupportratingscale.Datawerecollectedthroughface-to-faceinterviewsusingastructuredquestionnaire.MultiplelogisticregressionanalysisandconfirmatoryfactoranalysiswasusedtoexaminetherelationshipbetweensocialsupportandPTSD.RESULTS:Outofatotalof25,478subjectsinterviewed,2336(9.7%)werediagnosedashavingPTSD.PTSDwassignificantlyassociatedwithtotalsocialsupport(oddsratio[OR]0.80,95%confidenceinterval[CI],0.78–0.82),subjectivesupport(OR0.48,95%CI,0.44–0.52),andsupportutilization(OR0.53,95%CI,0.49–0.57).CONCLUSION:PTSDinfloodvictimsissignificantlyassociatedwithsocialsupport;subjectivesupportandsupportutilizationmayplaymoreimportantrolesinmitigatingtheimpactoffloodthanobjectivesupport.AnnEpidemiol2007;17:827–833.2007ElsevierInc.Allrightsreserved.KEYWORDS:Floods,PosttraumaticStressDisorder,SocialSupport,Epidemiology.INTRODUCTIONFloodisoneofthemostcommonandmostsevereformsofnaturaldisasters,accountingforuptoonehalfofallnaturaldisastersintheworld(1).InChina,floodingisafrequentoc-currence.AseverefloodthatstruckChina’sHunanprov-incein1998lefthundredsofthousandsofresidentshomeless.Manyinfrastructuralandagriculturalprojectsweredamagedaswell.Floodscanleadtodirecteconomicandpropertylosses,physicalinjuries,deaths,andpsycholog-icalinjuries.Posttraumaticstressdisorder(PTSD)isacommondisor-derindisastervictims.PTSDisasevereandcomplexdisor-derprecipitatedbyexposuretopsychologicallydistressingevents(2),anditischaracterizedbypersistentintrusivememoriesaboutthetraumaticevent,persistentavoidanceofstimuliassociatedwiththetrauma,andpersistentsymp-tomsofincreasedarousal(3).Inthepastdecades,thestudyofPTSDhasfocusedontrafficaccidents(4,5),violentcrimes(6),terroristattacks(7–9),hurricanes(10),earth-quakes(11),hijackings(12),rapes(13),andwarfare(14).Socialsupporthasbeenconsideredtobeanimportantfactorinfluencinganindividual’sreactionstostressanditalsohasabeneficialeffectonPTSD(15).Althoughpreviousstudieshaveassessedtheimpactoffloodsintermsofprop-ertyloss,mortality,andmorbidity(16),onlyafewstudieshavereportedPTSDinfloodvictims(17–20),andnonehasreportedtherelationshipbetweenPTSDandsocialsup-portinfloodvictims.Inthecurrentstudy,weexploredtherelationshipbetweensocialsupportandPTSDamongfloodvictimsinHunan,China.METHODSStudyPopulationVictimswhohadbeendirectlyexposedtothe1998summerfloods,whichlastedfor45days,inHunan,China,formedthetargetpopulation.Thestudyarealieswithinthecatch-mentareaofDongtingLake,whichislocatedsouthoftheFromtheSchoolofPublicHealth,CentralSouthUniversity,Changsha,Hunan,P.R.,China(S.F.,H.T.,A.B.,S.W.,A.L.,J.Z.,S.L.,T.Y.,X.L.,G.L.);theDepartmentofEpidemiology,SchoolofPublicHealth,NanhuaUniversity,Hengyang,Hunan(S.F.);OMNIResearchGroup,DepartmentofObstetrics&Gynecology,UniversityofOttawa,FacultyofMedicine,Ottawa,Canada(S.W.);andtheDepartmentofHealthStatistics,ShanxiMedicalUniversity,Taiyuan,ShanxiChina(Y.Z.).Addresscorrespondenceto:Dr.HongzhuanTan,SchoolofPublicHealth,CentralSouthUniversity,XiangyaRoad110,Changsha,Hunan410008,P.R.China.Tel.:[phone];fax:[phone].E-mail:[e-mail]12,2006;acceptedApril18,2007.2007ElsevierInc.Allrightsreserved.1047-2797/07/$–seefrontmatter360ParkAvenueSouth,NewYork,NY10010doi:10.1016/j.annepidem.2007.04.002SelectedAbbreviationsandAcronymsCIZconfidenceintervalORZoddsratioPTSDZposttraumaticstressdisordermiddlereachesoftheYangziRiverinsouthernChina,anditisalsoaflood-pronearea(Fig.1).ThecatchmentareaofDongtingLakeconsistsof31counties,coversanareaof31,000km2,andhasanestimatedhumanpopulationof11.3million.Residentshavesimilarnaturalconditionsaswellassimilarsocioeconomicandhealthstatus.Itisusuallywarm,humid,andrainyduringsummer,andmostoftheresidentsarefarmersandhaveloweducationallevels.Ourstudyareaalsoincluded7othercountiesinthewestofHunanprovincethathadbeenaffectedbytheflashfloods.Thesecountieshavesociode-mographiccharacteristicssimilartoothercountiesofDongtingLake’scatchmentarea.Ofthe38countiesaf-fected,31experienceddamagefromsoakingandcollapsedembankments,and7experiencedflashflooding.Weusedamultistagestratifiedandclustersamplingmethodtoselectstudysubjects.First,werandomlyselected7countiesfrom31countiesthatsufferedsoakingandcol-lapsedembankments(Yueyang,Lingxiang,Huarong,Qian-lianghu,Ziyang,Anxiang,Datonghu)and1countyfrom7countiesthatexperiencedflashflooding(Longshan).Then,bysystematicsamplingapproach,werandomlysam-pled50%oftownshipsinselectedcounties,50%ofvillagesinselectedtownships,and50%ofhouseholdsinse