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score on the Medical Lethality Scale, subjects were defined as High-Lethal- .... subjects. (54.9%) had at least a high school education; 45.1% had a trade school.
Journal of Personality Disorders, 19(4), 386–399, 2005  2005 The Guilford Press

HIGH-LETHALITY STATUS IN PATIENTS WITH BORDERLINE PERSONALITY DISORDER Paul H. Soloff, MD, Anthony Fabio, PhD, Thomas M. Kelly, PhD, Kevin M. Malone, MD, and J. John Mann, MD

Recurrent suicidal behaviors in patients with Borderline Personality Disorder (BPD) are often considered communicative gestures; however, 10% complete suicide. This study seeks to identify risk factors for suicide within a BPD sample by comparing patients with High- and LowLethality attempts. BPD attempters (n = 113) were assessed on demographic, diagnostic, and personality variables: clinical symptoms, suicidal behaviors; childhood, family, and treatment histories; social adjustment; and recent life events. Forty-four High-Lethality attempters, defined by a score of 4 or more on Beck’s Medical Lethality Scale, were compared to 69 Low-Lethality attempters. Discriminating variables were entered in a multivariate logistic regression model to define predictors of High-Lethality status. High-Lethality attempters were older, with children, less education, and lower socioeconomic class (SES) than Low-Lethality attempters. They were more likely to have Major Depressive Disorder (MDD), co-morbid Antisocial Personality Disorder (ASPD), and family histories of substance abuse. They reported greater intent to die, more lifetime attempts, hospitalizations, and time in the hospital. High-Lethality status was best predicted by low SES, co-morbid ASPD, extensive treatment histories, and greater intent to die. These characteristics resemble profiles of patients who complete suicide, are not specific for BPD, and do not include impulsivity, aggression, or severity of BPD criteria.

Suicide attempts by patients with Borderline Personality Disorder (BPD) are widely characterized as “communicative gestures,” or “ambivalent” attempts, yet 10% die by suicide, making BPD one of the most lethal of psychiatric disorders (Gunderson & Ridolfi, 2001; Paris & Zweig-Frank, 2001).

From the University of Pittsburgh, Western Psychiatric Institute and Clinic, Pittsburgh, PA (P.H.S., A.F., and T.M.K.). From the Department of Adult Psychiatry, Mater Hospital, University College, Dublin, Ireland (K.M.M.). From the New York State Psychiatric Institute, Columbia University, New York (J.J.M.). This paper was presented at the 157th Annual Meeting of the American Psychiatric Association, May 3, 2004 in New York City. This research was supported by the National Institute of Mental Health grant MH048463 (P.H.S.). Address correspondence and reprint requests to Dr. Paul H. Soloff, Western Psychiatric Institute and Clinic, 3811 O’Hara Street, Pittsburgh, PA 15213; E-mail: [email protected]

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BPD is the only psychiatric diagnosis defined, in part, by recurrent suicidal behavior (DSM-IV). The prevalence rate for suicide attempts among consecutively studied inpatients and outpatients with BPD is over 70%, with an average of 3 lifetime attempts per patient (Soloff, Lynch, Kelly, Malone, & Mann, 2000). Suicidal ideation and attempt behavior precede completion by years, becoming a chronic and habitual response to adverse life events (Mehlum, Friis, Vaglum, & Karterus, 1994). Surprisingly, little is known of risk factors for suicide completion in patients with BPD, or how an early history of repeated “gestures” progresses to death. In a stress-diathesis model for suicidal behavior, comorbidity with BPD represents a chronic vulnerability to suicide attempts and completion (Mann, Waternaux, Haas, & Malone, 1999). Comorbidity with BPD increases the likelihood of attempt behavior across diagnoses among inpatients, increases the number and lethality of suicide attempts among patients with Major Depressive Disorder (MDD) or substance use disorders (SUD), and is a risk factor for suicide completion in epidemiologic studies (Mann et. al., 1999; Fyer, Frances, Sullivan, Hurt, & Clarkin, 1998; Malone, Haas, Sweeney, & Mann, 1995; Corbitt, Malone, Haas, & Mann, 1996; Rich & Runeson, 1992). It is unclear to what extent the diathesis to suicide attempts and completion accompanying BPD is associated with its characteristic personality traits, or, alternatively, with the clinical, social, and vocational consequences of this chronic disorder. Impulsivity, aggression, and affective instability are prominent personality traits related to temperament in BPD. These personality traits have been associated with high-frequency, low-lethality suicide attempts independent of diagnostic context (Hirschfeld & Davidson 1988). Among inpatients with BPD, impulsivity, aggression, and antisocial personality traits are associated with both occurrence and frequency of suicide attempts; however, the relationship of these traits to medical lethality and suicide completion in BPD remains ill-defined (Soloff et. al., 2000; Brodsky, Malone, Ellis, Dulit, & Mann, 1997; Soloff et. al., 1994a). These personality traits are also associated with evidence of diminished central serotonergic regulation in BPD, and may represent a biologic diathesis for suicidal behavior (Oquendo & Mann, 2000). However, the biological component of BPD is just one part of a complex contribution to suicide risk. The risk of suicidal behavior in BPD may also be influenced by high rates of comorbidity with acute stressors such as MDD, or SUD. In a stressdiathesis model of suicide, MDD or SUD may be conceptualized as acute disorders (superimposed on the personality disorder) which increase suicide intent. However, the effects of these acute stressors on suicide attempts in patients with BPD are inconsistent across studies. MDD and SUD increase the number and seriousness of attempts among BPD adults and adolescents in some studies (Fyer et. al., 1998; Friedman, Aronoff, Clarkin, Corn, & Hurst, 1983), but not all (Soloff et. al., 1994a; Shearer, Peters, Quaytman, & Wadman, 1988). Risk factors among BPD patients who complete suicide are derived from

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retrospective, epidemiologic surveys of suicide in general populations (Runeson & Beskow, 1991; Isomesta et al., 1996), or follow-up studies of BPD patients treated at a single facility (Paris & Zweig-Frank, 2001; Kullgren, 1988; Kjelsberg, Eikeseth, & Dahl, 1991; Stone, 1989). These studies highlight the social and vocational consequences of BPD as risk factors for suicide completion. BPD patients who complete suicide are often characterized by lower socioeconomic status, and problems with school, employment, and finances (Runeson & Beskow, 1991). Mirroring the attempt literature, studies of suicide completion in BPD (or other Cluster B disorders) are inconsistent in regard to the effects of comorbid MDD or SUD, though less severe depressive syndromes (e.g., Depressive Disorder, NOS) appear highly prevalent among BPD completers (Isomesta et. al., 1996). Adverse childhood experiences, antisocial behavior, and comorbid Antisocial Personality Disorder (ASPD) are all more prevalent among BPD completers than comparison groups (Rich & Runeson, 1992; Runeson & Beskow, 1991; Isomesta et. al., 1996). Retrospective studies lack reliable, structured methods for making diagnoses, and systematic assessments of risk factors using standardized instruments. They generally do not assess core borderline traits such as impulsivity; clinical variables such as hopelessness, depressed mood, and hostility; or characteristics of suicidal behavior such as lethal intent and objective planning, which require prospective study designs. In this study, we used a prospective design to assess demographic, diagnostic, clinical, and psychosocial variables of High- and Low-Lethality attempters with BPD in an effort to define predictors of high-lethality behavior within the borderline disorder. Using a stress-diathesis model, we predicted that high-lethality attempts in BPD would be more likely when acute stressors, such as MDD or SUD, hopelessness, and anxiety, which intensify suicidal intent, are combined with high degrees of temperamental impulsivity or aggression. Although it is well understood that attempters are not the same as completers, High-Lethality attempters share many of the characteristics of completers, and may be studied prospectively as surrogates for patients who complete suicide (e.g., as “failed suicides”) (Beck, Steer, Kovacs, & Garrison,1975).

METHOD This study was approved by the University of Pittsburgh Institutional Review Board. Subjects were recruited from the inpatient and outpatient services of the Western Psychiatric Institute and Clinic, and by advertisement, from the surrounding community. After describing the study, written informed consent was obtained. Experienced clinical raters diagnosed Axis I disorders using the Structured Clinical Interview for DSM IIIR (SCID; Spitzer, Williams, Gibbon, & First, 1988) and Axis II disorders using the International Personality Disorders Examination (IPDE; Loranger, Sussman, Oldham, & Russakoff, 1987). (The DSM III-R was used for

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purposes of continuity with longitudinal studies.) The Diagnostic Interview for Borderline Patients (DIB; Gunderson, Kolb, & Austin, 1981), provided confirmation of BPD diagnosis. Final diagnoses were determined in a consensus conference of raters, using all available data. Patients with psychotic disorders, organic mood disorders, or bipolar disorders were excluded. Demographic data, suicide history, childhood and abuse histories, and family and treatment histories were obtained by semi-structured interviews, described previously (Soloff et al., 2000; Mann et al., 1999; Soloff, Lynch, & Kelly, 2002). A suicide attempt was defined as any self-injurious behavior with intent to die. Suicidal ideation and intent were assessed on the Scale for Suicidal Ideation (SSI) and Suicide Intent Scale (SIS), respectively (Beck, Schuyler, & Herman, 1974). A Subjective Intent factor and an Objective Planning factor were derived from the SIS using the method of Mieczkowicz et al. (Mieczkowski et. al., 1993). The Medical Lethality Scale, an ordinal scale quantifying degree of lethality by medical consequences, was scored for each attempt. Descriptive anchors define degrees of medical severity according to suicide method (Beck, Beck, & Kovacs, 1975). Using the median score on the Medical Lethality Scale, subjects were defined as High-Lethality attempters by a score of 4 or more for any lifetime attempt. (e.g., a score of 4 following a sedative drug overdose is defined as “comatose,” or “requiring hospitalization.”) Low-Lethality attempters had scores of 3 or less. Attempts were also classified according to violence of method (Soloff et al., 2000). Subjects were assessed for current state symptoms, personality traits, current social adjustment, reasons for living, and recent life events using standardized measures, described previously (Tables 1–3; Soloff et al., 2000; Mann et al., 1999; Kelly, Soloff, Lynch, Haas, & Mann, 2000).

STATISTICAL METHOD After testing for homogeneity and normality, univariate differences between High- and Low-Lethality attempters were tested using the Student’s t-test (two-tailed), the Chi-Square, or Mann-Whitney U-tests as appropriate. Continuous variables were correlated using Pearson or Spearman correlations. Missing data resulted in variable sample sizes for some analyses. Factor analyses were used where possible within content categories to reduce the number of intercorrelated variables. Multiple logistic regression was used to identify independent predictors of Lethality status following the modeling procedures of Hosmer and Lemeshow (Hosmer & Lemeshow, 2000). Because it is defined as an ordinal scale, the Medical Lethality Scale was not used as a continuous variable in these analyses. In a first exploratory step, variables discriminating between groups in the univariate analyses, with a significance threshold of p ≤ .1, were grouped by content category (Tables 1–3), and regressed on Lethality status one category at a time. This exploratory step was conducted without statistical

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SOLOFF ET AL. TABLE 1. Characteristics of High- vs. Low-Lethality Attempters: Demographic, Diagnostic and Clinical State Variables High Leth. Low Leth. t, df, p

Risk Factor

N = 44

1. Demographic Age: mean (SD) 31.3(8.8) Sex (male/female) 16(m) 28(f) Race (Caucasian) 35(Cau.) (Other) 9(Other) SES (I-III = High) 19(43.2%) (IV + V = Low) 25(56.8%) Ed. (≤HS/Trade) 25(56.8%) Married (ever) 12(45.5%) Children (%yes) 22(51.2%) Religion (%yes) 37(84.1%) 2. Diagnostic Major Depression 29(65.9%) Substance Abuse 31(70.5%) Any Axis II 30(68.2%) Any Cluster B 22(50.0%) ASPD 17(38.6%) 3. Clinical State Beck Depression Inv. 28.8(13.1) Hamilton Depr.-24 item 21.9(8.7) Beck Hopelessness 11.7 (6.1) GAS 46.6(10.4) MW = Mann Whitney U-test, z-score

Risk Factor

N = 69

!2, df, p

27.5(7.6) 16(m) 53(f) 52(Cau) 17(Other) 43(63.3%) 26(37.7%) 26(37.7%) 25(36.2%) 19(28.4%) 47(69.1%)

2.37, 111df, p. = .02 2.30, 1df, p ns 0.27, 1df, p ns

3.97, 0.95, 5.83, 3.19,

1df, 1df, 1df, 1df,

p p p p

< .05 ns = .016 ns

32(46.4%) 40(58.0%) 32(46.4%) 19(27.5%) 10(14.5%)

4.13, 1.79, 5.16, 5.86, 8.61,

1df, 1df, 1df, 1df, 1df,

p p p p p

= .04 ns = .02 = .015 = .003

25.8(13.1) 21.9(7.9) 10.9 (6.4) 49.0(13.3)

1.12, 97df, p ns 0.014, 98df, p ns MW: z 0.58, p ns 0.97, 106df, p ns

3.97, 1df, p < .05

Table 2. Suicide History and Personality Variables High Leth. Low Leth. N = 44 N = 69

t, df, p χ2, df, p

4. Suicide Hx Self-injury 21 (37.5%) 35 (62.5%) 1.11, 1df, p ns Age 1st attempt (yrs.) 17.9(12.4) 20.3(7.3) 1.27,111df, p ns # lifetime attempts 4.4 (3.7) 2.8 (2.7) 2.77,111df, p < .01 SIS intent (max)* 9.1(3.2) 7.7(3.9) 2.15,95df, p < .05 SIS plan (max) 7.0(3.4) 6.0(3.1) 1.57,100df, p ns SIS total (max) 16.5(5.9) 12.1(8.8) 3.11,106df, p = .002 Violent methods 29(65.9%) 33(47.8%) 3.55,1df, p = .06 5. Personality Barratt Impulsiveness 77.1(9.9) 73.9(20.4) 0.82,85df, p ns Buss-Durkee Hos. Inv. 46.(10.1) 45.7(11.9) 0.12,93df, p ns LHA** 24.9(7.3) 26.0(6.0) 0.86,101df, p ns MMPI-Pd 21.5(5.6) 21.0(7.4) 0.38,93df, p ns DIB Section Total 27.4(4.6) 27.8(5.2) 0.35,82df, p ns BPD criteria 5.1 (1.5) 5.4 (1.0) MW: z 1.05, p ns #SPD criteria 1.4 (1.4) 1.1 (1.2) MW: z 1.23, p ns IPDE total 55.7(24.5) 48.3(20.8) 1.62,99df, p = 0.1 * SIS: Suicide Intent Scale, lifetime maximum score. ** LHA: Brown-Goodwin Lifetime History of Aggression. MW = Mann Whitney U-test, z-score.

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Table 3. Childhood and Family History, Social Adjustment and Treatment Variables Risk Factor

High Leth. N = 44

Low Leth. N = 69

t, df, p χ2, df, p

6. Child/Fam. Hx. Sexual Abuse 15(50%) 19(43.2%) 0.33,1df, p ns Sep. par.