Posttraumatic Stress Disorder and Suicidal Behavior: Current Understanding and Future Directions Jaimie L. Gradus, DSc, MPH Epidemiologist, National Center for PTSD, VA Boston Healthcare System Associate Professor, Psychiatry and Epidemiology Departments, Boston University April 11, 2018
Overview PTSD and death from suicide Conflicting findings PTSD and suicide attempts More consistent findings AFSP-funded study on MA veterans Future directions and summary 1
Overview PTSD and death from suicide Conflicting findings PTSD and suicide attempts More consistent findings AFSP-funded study on MA veterans Future directions and summary 2
PTSD and Death from Suicide Topic of great interest due to concern about the suicide rate among military members and veterans 3
PTSD and Death from Suicide PTSD common in this population Natural hypothesis is that perhaps the greater suicide rate in this population is due at least in part to PTSD, or traumatic experiences Growing body of literature on the association between PTSD and death from suicide But this is a difficult topic to study. Availability of registry-based data on these populations enables work to be done The role of comorbid psychopathology is complicating 4
PTSD and Death from Suicide Active duty military members Entire active duty military population in 2005 (n = 2,064,183) and 2007 (n = 1,981,810) Air Force 2005 Air Force 2007 Army 2005 Army 2007 Odds Ratio 7.4 10.57 1.86 4.51 Sample sizes were too small to calculate an association for service members in the Marines or Navy Did not examine the role of comorbid psychopathology (Hyman et al., 2012) 5
PTSD and Death from Suicide Active duty military members US Army service members from 2001 2009 874 persons died by suicide Those who died by suicide were almost 13 times more likely to have been diagnosed with PTSD previously compared to all Army service members in the same time period Did not examine the role of comorbid psychopathology (Black et al., 2011) 6
PTSD and Death from Suicide Active duty military members Sample from the Millennium Cohort Study (n = 151,560), including current and former military personnel Sex- and age-adjusted association for PTSD and suicide of 1.8 Not statistically significant, likely due to sample size, so not included in adjusted model (LeardMann et al., 2013) 7
PTSD and Death from Suicide Veterans Vietnam veterans included in VA Agent Orange Registry Veterans with PTSD (n = 4,247) had an approximately 4 times higher suicide rate than veterans without PTSD (n = 12,010), adjusting only for age and race Also examined the association between PTSD and suicide among 3,246 veterans who had no comorbid diagnoses Among these veterans the suicide rate was almost 6 times as high as the expected rate in general population US males (Bullman & Kang, 1994) 8
(Ilgen et al., 2010) PTSD and Death from Suicide Veterans All veterans who used VA care in FY 1999 from fiscal year 1999 to FY 2006 (n = 3,291,891) Adjusting for age, male veterans with PTSD had 1.8 times the rate of suicide than male veterans without PTSD Female veterans with PTSD had 3.5 times the rate of suicide than female veterans without PTSD Did not examine the role of comorbid psychopathology 9
PTSD and Death from Suicide Veterans Veterans who received VHA services during FY 2007 or FY 2008 (n = 5,772,282) Found a an association between PTSD and suicide, adjusting for sex, age, and VISN Did not examine the role of comorbid psychopathology (Ilgen et al., 2012) 10
PTSD and Death from Suicide Veterans All male patients who used VA services in fiscal year 1999 (n = 2,962,810) Patients with PTSD and any psychiatric comorbidity had 2.6 times the rate of suicide than those with no psychiatric diagnoses Those with PTSD and no other psychiatric disorders had 1.6 times the rate of suicide than male veterans without any psychiatric diagnoses (Conner et al., 2013) 11
PTSD and Death from Suicide Veterans VHA patients from FY 2007 2008 (n = 5,913,648) In unadjusted analyses and demographically-adjusted analyses PTSD was associated with suicide with odds ratios that were approximately 1.3 After adjustment for comorbid psychiatric diagnoses the association was reduced to 0.77, indicating a protective effect of PTSD on suicide (Conner et al., 2014) 12
PTSD and Death from Suicide We know PTSD can have negative, long-term, consequences There is evidence of an association between PTSD and suicide from well-done epidemiologic studies BUT the 2014 study by Conner and colleagues is not the only one that has documented a protective association 13
PTSD and Death from Suicide Active duty All US military personnel from 2001 2011 (n = 3,795,823) Examined suicide during military service or post-separation Found a protective effect of PTSD across a range of time periods between diagnosis and death (effect estimates ranged from 0.63 to 0.82) compared to persons with no PTSD diagnoses These estimates were adjusted for demographics, military variables, and comorbid psychopathology (Shen et al., 2016) 14
PTSD and Death from Suicide Veterans VA patients who were discharged from an inpatient unit between 1994 1998 (n = 1,057) PTSD was protective against death from suicide when adjusting for demographics and psychiatric comorbidity (adjusted risk ratio = 0.62) (Desai et al., 2008) 15
PTSD and Death from Suicide Veterans All male veterans discharged from VA inpatient units from FY 2005 to FY 2010 (n = 346,662) Association between PTSD and suicide was 0.66 for the year following discharge, after adjustment for demographics and psychiatric comorbidity (Britton et al., 2017) 16
PTSD and Death from Suicide Veterans VA patients receiving treatment for depression from 1999 2004 (n = 807,694) Also found the association between PTSD and suicide to be protective (adjusted hazard ratio = 0.77). (Zivin et al., 2007) 17
PTSD and Death from Suicide Understanding disparate findings Most studies have documented that PTSD is associated with an increased risk for suicide Still more than a few well-done studies have found no association or a protective association Potential explanations span etiologic and methodologic reasoning Assessment of psychiatric comorbidity Reflect true differences across people, place and time 18
Overview PTSD and death from suicide Conflicting findings PTSD and suicide attempts More consistent findings AFSP-funded study on MA veterans Future directions and summary 19
PTSD and Suicide Attempt 5877 general population participants in the National Comorbidity Survey PTSD was associated with: suicidal ideation (OR = 5.1, 95% CI = 3.9, 6.8) suicide attempts (OR = 6.0, 3.4, 10.7), adjusting for demographic variables suicide plans among those with suicidal ideation (OR = 2.4, 95% CI = 1.7, 3.3) impulsive attempts among those with suicidal ideation (OR = 1.7, 95% CI = 1.1, 2.7) Adjusted for psychiatric comorbidity (Kessler et al., 1999) 20
PTSD and Suicide Attempt Data from people in 21 countries included in the WHO World Mental Health Surveys (n = 108,664) Adjusting for demographics and other psychiatric disorders, PTSD was associated with suicidal ideation in developed countries (OR = 2.7, 95% CI = 2.2, 3.2) suicidal ideation in developing countries (OR = 3.9, 95% CI = 2.7, 5.6) suicide attempt in developed countries (OR = 3.0, 95% CI = 2.3, 3.8) suicide attempt in developing countries (OR = 5.6, 95% CI = 3.5, 8.8) (Nock et al., 2009) 21
PTSD and Suicide Attempt 9,282 general population participants in the NCS-Replication (NCS-R) In multivariate models, those with PTSD had greater odds of: suicidal ideation (OR = 1.7, 95% CI = 1.4., 2.0) suicide attempts (OR = 2.1, 95% CI = 1.5, 2.9) Among those with suicidal ideation, PTSD was associated with suicide plans (OR = 1.6, 95% CI = 1.2, 2.3) and unplanned attempts (OR = 2.4, 95% CI = 1.3, 4.5) (Nock et al., 2010) 22
Overview PTSD and death from suicide Conflicting findings PTSD and suicide attempts More consistent findings AFSP-funded study on MA veterans Future directions and summary 23
PTSD and Suicide Attempt Goals of study: Examine the association between PTSD and suicide attempt in a population-based sample of veterans who use VA services Examine the interactions between PTSD and depression and PTSD and substance abuse in predicting suicide attempts Examine gender differences in these associations 24
PTSD and Suicide Attempt Sample Base population : patients who received care at a Massachusetts VA hospital between 2000 and 2008 VHA health care user: at least one primary care and one other health care visit in the twelve months prior PTSD diagnosis 25
PTSD and Suicide Attempt Sample PTSD cohort: patients who received a PTSD diagnosis (ICD-9-CM code 309.81) at a Massachusetts VA facility between 2000 and 2008 (n = 16,004) Comparison cohort: veterans who received care at a Massachusetts VA facility, but never received a PTSD diagnosis (n = 52,502) Matched to PTSD patients, with a ratio of up to 5 to 1, on five-year age categories and gender 26
PTSD and Suicide Attempt Data Sources Data were obtained for the following variables during the study period: depression diagnoses (ICD-9-CM codes: 296.2-296.3) substance use disorders (ICD-9-CM codes: 303.xx-305.9) anxiety disorders (ICD-9-CM codes: 300, 300.01-300.02) suicide attempt resulting in an inpatient hospitalization (ICD-9-CM codes: E950-E959) Veteran s person-time was measured from date of PTSD diagnosis (or the index date for comparison group members) to the first suicide attempt resulting in hospitalization, death, or end of the last fiscal year in which a patient fulfilled the study definition of a VA health care user, whichever came first 27
PTSD and Suicide Attempt Analyses Descriptive analyses Unadjusted rate ratios and corresponding confidence intervals Rate ratios then calculated adjusting for marital status, depression, alcohol or drug abuse or dependence, anxiety disorder diagnoses, and prior suicide attempt Interaction between PTSD and depression diagnoses and PTSD and substance abuse diagnoses were assessed by calculating the interaction contrast (IC) while adjusting for identified confounders 28
PTSD and Suicide Attempt (N = 15,056) (N = 948) (N = 48,042) Demographics Race, n (%) White Black Asian American Indian Unknown Marital Status Married Divorced Never/Single Widowed Single Unknown 157 (1.1%) 16 (1.8%) 1,708 (3.6%) 1,948 (43.9%) Age, Mean (SD, range) 56.4 (13.8, 19.8 44.3 (12.2, 19.4 59.4 (15.1, 44.8 (12.1, 16.7 96.7) 85.5) 17.3 97.4) 89.6) Comorbidities Depression diagnosis, n (%) 1,704 (11.3%) 175 (18.5%) 1,135 (2.4%) 117 (2.6%) Alcohol abuse/dependence, n (%) 2,381 (15.8%) 97 (10.2%) 2,604 (5.4%) 49 (1.1%) Drug abuse/dependence, n (%) 2,729 (18.1%) 153 (16.1%) 4,350 (9.1%) 162 (3.6%) VETERANS Anxiety disorders, HEALTH n (%) ADMINISTRATION 1,949 (13.0%) 132 (13.9%) 1,660 (3.5%) 124 (2.8%) Prior suicide attempt, n (%) 44 (0.3%) 5 (0.5%) 8 (0.02%) 3 (0.07%) PTSD (N = 16,004) Males Females 12,872 (88.0%) 1,314 (9.0%) 46 (0.3%) 30 (0.21%) 368 (2.5%) 6,800 (46.9%) 3.532 (24.4%) 3,110 (21.4%) 659 (4.5%) 247 (1.7%) 755 (83.0%) 126 (13.9%) 6 (0.7%) 3 (0.3%) 20 (2.2%) 211 (23.3%) 286 (31.5%) 333 (36.7%) 47 (5.2%) 14 (1.5%) Males 36,599 (85.2%) 2,958 (6.9%) 149 (0.4%) 106 (0.3%) 3,168 (7.4%) 22,267 (47.1%) 9,910 (21.0%) 10,092 (21.3%) 3,068 (6.5%) 265 (0.6%) Comparison Group (N = 52,502) Females (N = 4,460) 2,297 (68.3%) 306 (9.1%) 42 (1.3%) 12 (0.4%) 705 (21.0%) 923 (20.8%) 593 (13.4%) 796 (18.0%) 156 (3.5%) 18 (0.4%) 29
PTSD and Suicide Attempt Results Men Women Unadjusted 5.0 (3.7, 6.8) 24 (8.2, 68) Adjusted* 3.2 (2.3, 4.5) 16 (4.8, 56) *adjustment for baseline marital status, depression, alcohol and drug abuse/dependence, anxiety disorder diagnoses and prior suicide attempt Pattern of results among the subsample without prior suicide attempt was consistent with presented results 30
PTSD and Suicide Attempt Gender-stratified Incident Rates and Interaction Contrast for Depression and PTSD Men PTSD + PTSD - Depression + 211.9 142.3 Depression - 82.6 24.6 aic = 11.6 Women PTSD + PTSD - Depression + 940.6 80.5 Depression - 137.4 25.0 Note: All per 100,000 person-years. aic = adjusted interaction contrast; PTSD = posttraumatic stress disorder Analyses adjusted for depression, anxiety disorders, and prior ISH. aic = 747.7 31
PTSD and Suicide Attempt Gender-Stratified Incident Rates and Interaction Contrast for Alcohol Abuse and Dependence and PTSD Diagnoses Men PTSD + PTSD - Alcohol Abuse/Dependence + 205.13 131.99 Alcohol Abuse/Dependence - 65.00 13.35 aic = 21.49 Women PTSD + PTSD - Alcohol Abuse/Dependence + 691.89 220.73 Alcohol Abuse/Dependence - 424.46 15.65 Note: All per 100,000 person-years. aic = adjusted interaction contrast; PTSD = posttraumatic stress disorder Analyses adjusted for depression, anxiety disorders, and prior ISH. aic = 62.35 32
PTSD and Suicide Attempt Gender-Stratified Incident Rates and Interaction Contrast for Drug Abuse and Dependence and PTSD Diagnoses Men PTSD + PTSD - Drug Abuse/Dependence + 87.22 48.18 Drug Abuse/Dependence - 60.98 19.16 aic = -2.78 Women PTSD + PTSD - Drug Abuse/Dependence + 700.03 86.33 Drug Abuse/Dependence - 375.75 18.38 Note: All per 100,000 person-years aic = adjusted interaction contrast; PTSD = posttraumatic stress disorder Analyses adjusted for depression, anxiety disorders, and prior ISH. aic = 256.33 33
PTSD and Suicide Attempt Conclusions Evidence of a strong association between PTSD and suicide attempt among MA veterans who use VA services When PTSD and depression co-occur or PTSD and substance abuse co-occur risk of suicide attempt is increased, especially for female VHA patients 34
Overview PTSD and death from suicide Conflicting findings PTSD and suicide attempts More consistent findings AFSP-funded study on MA veterans Future directions and summary 35
Future Directions and Summary Novel methods Machine learning Sequence analysis Multiple sources of data Ultimate goal: better prediction and prediction tools 36
Future Directions and Summary Majority of studies point to an increased risk of suicide associated with PTSD Studies that do not corroborate these findings are too many to be discounted Further research is needed to understand this potentially critical association The association between PTSD and suicide attempt is more substantiated Gender differences is an important area for research on both outcomes to explore further Machine learning and other novel methods will expand what we know about these areas Also result in risk assessment tools 37
Acknowledgements This work was supported by grant YIG-1-069-11 (PI: Gradus) from the American Foundation for Suicide Prevention and grant 1R01MH109507 (PI: Gradus) from the National Institute of Mental Health Collaborators Ryan Ferguson, DSc Sarah Leatherman, PhD Matthew Miller, MD Lisa Myers, PhD Andrew Curreri Sanjay Raju 38
Additional Readings Gradus, J. L. (2017). PTSD and Death from Suicide. PTSD Research Quarterly, 28(4). Gradus, J. L., Leatherman, S., Raju, S., Ferguson, R. E., Miller, M. (2014). Posttraumatic stress disorder, depression, and non-fatal intentional self-harm in Massachusetts veterans. Injury Epidemiology, 1, 20. Gradus, J. L., Leatherman, S., Curreri, A., Myers, L. G., Ferguson, R., Miller, M. (2017). Gender Differences in Substance Abuse, PTSD and Intentional Self-Harm among Veterans Health Administration Patients. Drug and Alcohol Dependence, 171, 66-69. 39