Childhood Adversities Associated With Risk for Suicidal Behavior

It has been estimated that worldwidealmost a million persons commit suicideevery year.¹ In the United States, theannual suicide rate is approximately 12per 100,000.² In Europe, the suicide rateranges from approximately 4 per100,000 (Greece, Italy, Spain) to 40 per100,000 (Hungary, Finland, Sweden).³Intermediate suicide rates such as 22per 100,000 have been reported in othernations (eg, China).⁴ The most commonimmediate risk factors for suicide aremental disorders, particularly mood andsubstance use disorders. Almost 90%of suicide attempts take place amongpersons with a current mental disorder;and approximately 80% of these personsdo not receive treatment before attemptingsuicide.^5,6 Other suicide risk factorsinclude chronic pain or psychiatricdisorder of one's partner.^7,8

Suicide rates increased in many partsof the world from 1970 to 1990, followedby a plateau or a slight decreasein recent years.^9,10 Suicide is relatively rare among children younger than 10years (0.05 cases per 100,000). In earlyadolescence (10 to 14 years), there isa 30-fold increase in risk (approximately1.5 cases per 100,000). Among15- to 24-year-olds, an additional 10-fold rise in risk has been observed (13cases per 100,000).¹¹ Although womenreport more suicide attempts andsuicidal ideation, men have the highestrate of completed suicide.^12,13

Epidemiology of severechildhood adversities

Documented cases of childhood physicalabuse, sexual abuse, and neglectare relatively common in the generalpopulation (approximately 12 victimsper 1000 children). In 2004, an estimated872,000 children were found tobe victims of childhood abuse or neglectin the United States.¹⁴ Because manycases of abuse and neglect are notreported to authorities, the actual frequencyof childhood maltreatment islikely to be substantially higher.¹⁵Physical punishment during childhoodis common (approximately 60% ofadults in the United States report havingexperienced corporal punishment in childhood). More severe acts of physicalviolence and victimization duringchildhood (eg, being struck with objects)were reported by 11% of adults in 1985;the prevalence of childhood physicalabuse was estimated to be 1.9% in1985.

The prevalence of sexual abuse wasinvestigated in a recent meta-analysisof 168 studies including almost 1 millionpersons.¹⁶ Worldwide, about 5% ofwomen and 3% of men reported havingbeen sexually abused during childhood(intercourse or anal/oral contact). Anadditional 13% of women and 3% ofmen reported less severe incidents ofsexual activity (unwanted physicalcontact without intercourse or anal/oralcontact). Moreover, 7% of women and3% of men reported incidents of childhoodsexual abuse without physicalcontact, such as exhibitionism.

Specific childhoodadversities associated withrisk for suicidal behavior

Numerous studies have investigated theassociations of specific childhood adversitieswith suicide risk. These adversitiesinclude childhood maltreatment, problematicfamily relationships, socioeconomichardship, and difficultrelationships with peers (Table).^17-28Childhood physical and sexual abusehave been found to be particularly importantrisk factors in retrospective^29-30and prospective studies^31,32 in populationsof young adults²⁰ and older adults.³³Problematic family relationships, includingcertain combinations ofmaladaptive parental behaviors (eg, affectionlessor overprotective parenting),have been reported to be associated withrisk for suicide.^34-36

Other risk factors include a historyof mental disorders,⁹ parental psychopathology,³⁷ a family history of suicidalbehavior,¹⁷ and parental financial hardshipor unemployment.²¹ Suicidal behavioris known to be multidetermined, withmany risk factors playing importantcontributory roles.^9,21,38 For example,one study showed that of 70 risk factorsinvestigated in bivariate analyses, morethan 50 were significantly associatedwith suicidal ideation or deliberate selfharm.³⁹ In addition, persons who haveexperienced a series of adversitiesduring childhood and adolescence havebeen found to be at particularly elevatedrisk for suicide.^35,40

Several studies have examined a varietyof risk factors and their differentialcontributions to later suicide risk. Studiesusing cumulative adversity indices haveindicated that the predictive power forsingle adversities was lower than for thecombined effects of multiple riskfactors.^29,38 The underlying rationale ofthe use of summation indices is that mostpersons are resilient enough to cope with a certain amount of adversity, but ifadversities rise above this threshold,coping abilities fail and risk for suicidalbehavior increases.^21,41 When extremegroups are compared, this can result inextraordinarily large effect sizes. For example, Felitti and associates²⁹ foundthat there was a 25-fold increase in theprobability of reporting a suicide attemptby persons who reported numerouschildhood adversities compared withpersons who reported only one riskfactor or none at all.⁴²

Childhood maltreatment or victimization
Bullying, school violence, criminal victimization^18,48
Physical abuse^{15,19,28,40,48}
Psychological abuse, verbal abuse, or scapegoating^28,48
Sexual abuse^{5,20,29-32,40,43,48}

Problematic parenting or family environment
Affectionless or overprotective parenting^34-36,44
Chronic or severe conflict with family members^{15,19,29,40,45,48}
Harsh physical punishment^15,36,48
Parent-child attachment difficulties^21,28
Poor communication with family members²⁸

Socioeconomic hardships
Change in residence^5,40
Educational and occupational problems^{9,22,24,40,48}
Low parental educational aspirations^24,48
Poverty^5,21,48
Parental unemployment^21,48

Other childhood adversities
Difficult relationships with friends and peers^{5,9,18,21-24,26,40,47,48}
History of mental disorder or suicide attempts^{5,9,18,21-24,26,40,47,48}
History of suicidal behavior among family members^{5,9,17,21,22,24,40,48}
Parental or familial psychopathology^{5,9,19,21,22,24,28,37,40,48}
Parent marital dysfunction^{5,9,21,22,24,28,40,48}
Legal or disciplinary problems^{5,9,18,21,22,24,40,48}
Loss of parent/caregiver due to death or separation^{5,9,21,22,24,28,40,48}

Theoretical models of suicide etiology

A number of different theoreticalmodels have been developed to explainthe underlying mechanisms that lead tosuicidal behavior.^{21,22,26,37,38} Several of these theories have included a widerange of risk factors. In particular, somerecent models have focused on the associationbetween childhood adversitiesand suicide risk. For example, Bergenand associates⁴³ constructed a model with 2 hypothesized paths from childhoodsexual abuse to suicide risk: (1)via depression and (2) via hopelessness.Suicide risk was defined as increasedsuicide ideation, plans, threats, anddeliberate self-harm. Childhood sexualabuse was associated with suicideattempts through the mediation of hopelessnessand depressive symptoms.Findings indicated that hopelessnesswas more strongly linked with sexualabuse in boys, while depression wasmore strongly linked with high suiciderisk in girls.

Developmental theorists have hypothesizedthat negative life events andinterpersonal difficulties may play animportant role in determining whetherchildhood adversities contribute to theonset of suicidal behavior. Case-controlresearch has suggested that interpersonalconflict or separation during adulthoodmay play a role in determiningwhether neglectful and overprotectiveparenting during childhood predictssuicidal behavior during adulthood.⁴⁴

Longitudinal studies have suggestedthat low family cohesion, low familyexpressiveness, and high family conflictmay mediate the association betweenmaternal depression and adolescentsuicidality,⁴⁵ that adolescents' relationshipswith their parents may moderatethe association between stressful lifeevents and depressive symptoms,⁴⁶ andthat stressful life events may mediatethe association between certain typesof childhood adversity and risk forsuicidal behavior during adolescence orearly adulthood.⁴⁷ These findings andresearch indicating that disruption ofinterpersonal relationships is a predominantrisk factor for suicide^21,23 suggestthat suicide attempts may often be attributableto severe chronic or episodicinterpersonal difficulties among personswho had particularly problematic relationshipswith their parents duringchildhood.^18,26

An interpersonal model of suicide,based on research indicating that majorproblems in interpersonal relationshipscontribute to the onset of suicidality,was developed by Johnson andcolleagues.⁴⁸ This model hypothesizesthat childhood maltreatment and problematicfamily relationships duringchildhood contribute to a persistentelevation in risk for suicide duringadolescence and adulthood. Personswith a history of childhood maltreatmentor highly problematic family relationshipsare hypothesized to be atparticularly elevated risk for suicidalbehavior when they experience severedisruptions in current interpersonal relationshipsduring adolescence or adulthood(Figure 1 [see June 2006 Psychiatric Times, page 33]). Research has providedsupport for the interpersonal model ofsuicide (Figure 2).⁴⁸

Suicidal behavior is often attributableto a combination of proximal and distalrisk factors. Several diathesis-stress theorieshave been advanced regarding biologic,psychological, and social diathesesor vulnerability factors that may contributeto increased risk for suicidal behaviorin the context of elevated stress(chronic stress or stressful life events).Proposed biologic diatheses includegenetic factors, prenatal factors, andpersistent alterations in neurobiologicfunction and structure that may resultfrom severe traumatization during childhood.^49,50 Learning and conditioning mayalso contribute to the development ofdiatheses for depression and suicidality,such as learned helplessness, hopelessness,and a persistent suppressionof the will to live.^51-54

Treatment implications

Research on childhood adversities andsuicidality has important clinical implications.Standard medical managementof the psychiatric disorders that are typicallyassociated with risk for suicidalbehavior (eg, major depressive disorder)is appropriate and, in almost allcases, necessary. A biopsychosocialapproach is likely to be particularly helpfulin assessing the suicidal patient anddetermining the most appropriate treatment.This approach includes ruling outpotential physiologic causes of psychiatricproblems (eg, thyroid disease),determining whether pharmacotherapeuticintervention is appropriate, andassessing the likelihood of futuresuicidal behavior. In addition to treatingthe psychiatric symptoms that mayhave helped precipitate a suicidal act,clinicians should assess the history ofinterpersonal problems and childhoodadversities that may have played animportant causative role in the developmentof a patient's suicidal ideationand behavior.

Following a systematic assessmentof a patient's history of adversities andinterpersonal difficulties, appropriatetreatment may often require psychotherapeuticor psychosocial intervention.Patients who are in a state of acutedespair about their life situation, basedon a history of profound interpersonaldifficulties (eg, failed romantic, peer,or occupational relationships), oftenoriginating in childhood adversities,may need assistance in developingimproved interpersonal skills andbecoming more hopeful about thefuture.

Thus, while it is important to effectivelytreat the psychiatric disordersthat might precede suicidal behavior, itis equally important to address interpersonalproblems or crises that maylead to attempted suicide.²²

Counseling has been found to playan important role in suicide preventionamong individuals with and without ahistory of suicidal behavior.⁵⁵ Researchindicates that psychotherapeutic interventionsoften play an important rolein the effective treatment of depressedand suicidal persons. For example, arecent large study demonstrated thatpatients with chronic major depressionwho had a history of childhood adversitywere more likely to respond topsychotherapy than to medication.⁵⁶

Some types of psychological interventions,including cognitive therapy,have been found to be effective inpreventing suicide attempts by personswho have attempted suicide in the past.⁵⁷Another approach that may be helpfulin treating suicidal persons is dialecticbehavior therapy,⁵⁸ an approach thatwas developed for treating individuals with borderline personality disorder, acondition often characterized by suicidalor self-destructive behavior.

Community- and school-based suicideprevention intervention programshave been developed, although the effectivenessof such programs has not yetbeen well established.^59-61 Follow-upcare is also likely to play an importantrole in effective suicide prevention.⁶²Because persons who have previouslyattempted suicide are at particularlyelevated risk for subsequent suicidalbehavior, monitoring a patient's functioningand well-being during the firstfew weeks and months after a suicideattempt may be of critical importance.

Serious suicidal ideation is relativelycommon in the general population. Forexample, a recent large-scale epidemiologicstudy has indicated that approximately16% of the adolescents in theUnited States may have had seriousthoughts of killing themselves withinthe past year.⁶³ It has been estimatedthat approximately 3% of the adults inthe United States have had serioussuicidal ideation within the past year.⁶⁴Most persons in the general populationwho have serious suicidal ideation donot receive psychological or emotionalcounseling.^63,64 Improved recognitionand treatment of moderate to severesuicidal ideation may contribute to areduction in the prevalence of suicidalbehavior.⁵⁵

Conclusion

Research has supported the inferencethat childhood adversities are associatedwith elevated risk for suicidalbehavior during adolescence and adulthood.Although several theories havebeen developed to explain these associations,further research is needed totest these hypotheses and to identifyoptimal interventions. Further researchis also needed to improve our understandingof the causal mechanismsunderlying these associations.²⁸ Acutesuicide prevention strategies shouldfocus on the effective treatment of psychiatric disorders that contributedto attempted suicide and on the interpersonal,occupational, and otherpsychosocial crises that may precipitatesuicidal behavior.

Many patients who attempt suicideare in a profound state of despair abouttheir life situation, and this kind ofdespair often develops in persons who are hopeless about their ability to overcomethe challenges that they face.⁵⁹ Inorder to increase the patient's will tolive, and to decrease the patient's wishto die, it is often necessary to assessthe history of childhood adversitiesand interpersonal difficulties that mayhave caused the patient to becomeprofoundly hopeless about the future.In addition to assessing these types ofadversities, it is important to (1) establisha strong therapeutic alliance withthe patient, (2) focus on helping thepatient become more hopeful about thefuture, (3) maintain ongoing contactwith the patient, and (4) monitor thepatient's will to live, feelings of despairand hopelessness, and ongoing suicidalideation.

Dr Hardt is with the Clinic for PsychosomaticMedicine and Psychotherapy at the JohannesGutenberg University of Mainz in Germany. Hereports that he has no conflicts of interestconcerning the subject matter of this article.

Dr Johnson is associate professor of clinicalpsychology in the department of psychiatry ofthe College of Physicians and Surgeons atColumbia University and a research scientistat the New York State Psychiatric Institute inNew York City. He reports that he has no conflictsof interest concerning the subject matterof this article.

Ms Courtney is a researcher at the New YorkState Psychiatric Institute in New York City. Shereports that she has no conflicts of interestconcerning the subject matter of this article.

Dr Sareen is with the department of psychiatryand community health sciences at theUniversity of Manitoba in Canada. He reportsthat he is on the speakers' bureau forGlaxoSmithKline, Wyeth-Ayerst, Lundbeck,and AstraZeneca.

References:

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