精神病学精神病学Affective(mood)Disorders XIE Guang-rong M.D.Definition Affectivedisordersarecharacterizedbyobviousandpersistentelationordepressionofmood.Themooddisturbanceiscommonlyassociatedwithcognitiveandbehavioralchanges.Inseverecases,psychoticsymptoms,suchashallucinationanddelusion,maybeobserved.Thereisarecurrenttendency.Incertaincases,anepisodemaybecomechronicandresidualsymptomsareobserved.TheClassificationofAffectiveDisorders Manic episode (mania) Depression single episode (unipolar) recurrent episode With or Affective without Disorders Bipolar-I(with mania) Psychotic Bipolar Bipolar-II(with hypomania) symptom disorders Mixed type Rapid-cyclingbipolar disorder Dysthymia Cyclothymia disorder ClinicaldescriptionofmooddisordersTheepisodeSeverityMild,moderate,orsevereTypeDepressive,manic,mixedSpecialfeaturesWithmelancholicsymptomsWithneuroticsymptomsWithpsychoticsymptomsWithagitationWithretardationorstuporThecourseUnipolarorbipolarAetiologyPredominantlyreactivePredominantlyendogenousEtiologyGeneticCausesFamilyStudies:InastudyattheNationalInstituteofMentalHealth,25%ofrelativesofbipolarprobandswerefoundtohavebipolardisorderorunipolarillness(depression)themselves,comparedto20%ofrelativesofunipolarprobandsand7%ofrelativesofcontrolsubjects.Somedatahavesupportedmultifactorialmodels,Thesemodelsimplymultiplefactors:genetic,environmental,orboth.Analternativeexplanationisheterogeneity.Inotherwords,singlemajorgenesareimportantinatleastsomefamilies,butitisnotthesamegeneineachfamily.Twinstudies:Onaverage,MZtwinpairsshowconcordance65%ofthetime,andDZtwinpairsshowconcordance14%ofthetime.AdoptionStudies:Inonestudy,theriskforaffectivedisorderinthebiologicalrelativesofbipolarprobandswas31%asopposedto2%intherelativesofcontrolprobands.Theriskinbiologicalrelativesofadoptedbipolarprobandswassimilartotheriskinrelativesofbipolarprobandswhowerenotadoptedaway(26%).Adoptiverelativesdidnotshowincreasedrisk.Adoptionstudiesthatusedabroaderclassofaffectiveprobandsshowedevidenceforgeneticfactorsbutalsopossibleenvironmentalinfluences.Molecular GeneticsLinkageStudiesChromosomalLocationReference18pBerrettinietal19Stineetal199521qStraubetal1994Detera-Wadleighetal1996Xq26Pekkarinenetal199511p15Egelandetal1987Kelsoeetal1991Gurlingetal19955qCoonetal19934pBlackwoodetal199618qFreimeretal1996Stineetal1995Other(including10p,12q)Craddocketal1994Ewaldetal1995Ginnsetal1996NIMHGeneticsInitiative1997Summaryn The lifetime risk for severe affective disorder is about 8%. Risk is increased to about 20% in first-degree relatives of unipolar patients and to 25% in first-degree relatives of bipolar patients. Risk appears to be 40% in relatives of schizoaffective patients. The risk to offspring of two affectively ill parents is more than 50%. Overall risk figures appear to be rising in recent years.Biological theoriesNeurotransmitters.We now know that all clinically effectiveantidepressantsincreaseneurotransmitterconcentrationsatpostsynapticreceptorsitesbyinhibitingtheirreuptake(intothepresynapticneuron)fromthesynapticcleft,Thisactionhasledtothehypothesisthatdepressioniscausedby a neurotransmitter deficiency and thatantidepressants exert their clinical effect bytreatingthisimbalance.Theserotonin-norepinephrine-gluco-corticoidlinkhypothesisofaffectivedisorders.Neuroendocrine factors.Thetwoendocrinesystemsmostextensivelystudiedinpsychiatryarethehypothalamic-pituitary-adrenal(HPA)axisandthehypothalamic-pituitary-thyroid(HPT)axis.Abouthalfofpatientswithmajordepressionexhibitcortisolhypersecretionthatreturnstonormaloncethedepressioniscured.Life events Recent evidence confirms that crucial life events, particularly the death of loss of a loved one , can precede the onset of depression. However, such losses precede only a small number of cases of depression.Fewer than 20% of individuals experiencing losses become clinically depressed . These observations argue strongly for a predisposing factor, possibly genetic , psychosocial,or characterological in nature. DepressiveepisodeDefinitionThedisorderischaracterizedbydepressedmoodthatisoutofkeepingwiththecircumstances.Itmayvaryfromlowmoodtomelancholia,orevenstupor.Inseverecases,psychoticsymptoms,suchasdelusionsandhallucinations,maybepresent.EpidemiologySymptomsanddisordersofthedepressionspectrumarerathercommon.Lifetimeprevalenceratesfordepressivesymptomsare13%20%andformajordepressivedisorder3.7%6.7%.Majordepressivedisorderisabouttwotothreetimesascommoninadolescentandadultfemalesasinadolescentandadultmales.Inprepubertalchildren,boysandgirlsareaffectedequally.Ratesinwomenandmenarehighestinthe25-to44-year-oldagegroup.Signs & SymptomsMajor depressive episode Thecardinalfeatureofamajordepressiveepisodeisadepressedmoodorthelossofinterestorpleasurethatpredominatesforatleast2weeksandcausessignificantdistressorimpairmentintheindividualssocial,occupational,orotherimportantareasoffunctioning.1. Depressed mood.Depressedmoodisthemostcharacteristicsymptom,occurringinover90%ofpatients.Thepatientusuallydescribeshimselforherselfasfeelingsad,low,e