1. 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

2. 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

3. 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

4. PTSD and Death from Suicide
Topic of great interest due to concern about the suicide rate among military members and veterans

5. 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

6. 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)
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)
Air Force 2005
Air Force 2007
Army 2005
Army 2007
Odds Ratio
7.4
10.57
1.86
4.51

7. 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)

8. 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)

9. 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)

10. PTSD and Death from Suicide
Veterans
All veterans who used VA care in FY 1999 from fiscal year 1999 to FY (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
(Ilgen et al., 2010)

11. 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)

12. 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)

13. 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)

14. 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

15. 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)

16. 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)

17. 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)

18. 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)

19. 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

20. 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

21. 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)

22. 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)

23. 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)

24. 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

25. 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

26. 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

27. PTSD and Suicide Attempt
Sample
PTSD cohort: patients who received a PTSD diagnosis (ICD-9-CM code ) 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

28. PTSD and Suicide Attempt
Data Sources
Data were obtained for the following variables during the study period:
depression diagnoses (ICD-9-CM codes: )
substance use disorders (ICD-9-CM codes: 303.xx-305.9)
anxiety disorders (ICD-9-CM codes: 300, )
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

29. 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

30. PTSD and Suicide Attempt
PTSD
(N = 16,004)
Comparison Group
(N = 52,502)
Males
(N = 15,056)
Females
(N = 948)
(N = 48,042)
(N = 4,460)
Demographics
Race, n (%)
White
Black
Asian
American Indian
Unknown
12,872 (88.0%)
1,314 (9.0%)
46 (0.3%)
30 (0.21%)
368 (2.5%)
755 (83.0%)
126 (13.9%)
6 (0.7%)
3 (0.3%)
20 (2.2%)
36,599 (85.2%)
2,958 (6.9%)
149 (0.4%)
106 (0.3%)
3,168 (7.4%)
2,297 (68.3%)
306 (9.1%)
42 (1.3%)
12 (0.4%)
705 (21.0%)
Marital Status
Married
Divorced
Never/Single
Widowed
Single
6,800 (46.9%)
3.532 (24.4%)
3,110 (21.4%)
659 (4.5%)
247 (1.7%)
157 (1.1%)
211 (23.3%)
286 (31.5%)
333 (36.7%)
47 (5.2%)
14 (1.5%)
16 (1.8%)
22,267 (47.1%)
9,910 (21.0%)
10,092 (21.3%)
3,068 (6.5%)
265 (0.6%)
1,708 (3.6%)
923 (20.8%)
593 (13.4%)
796 (18.0%)
156 (3.5%)
18 (0.4%)
1,948 (43.9%)
Age, Mean (SD, range)
56.4 (13.8, 19.8 – )
44.3 (12.2, 19.4 – )
59.4 (15.1,
17.3 – 97.4)
44.8 (12.1, 16.7 – )
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%)
Anxiety disorders, n (%)
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 and Suicide Attempt

31. PTSD and Suicide Attempt
Results
*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
Men
Women
Unadjusted
5.0 (3.7, 6.8)
24 (8.2, 68)
Adjusted*
3.2 (2.3, 4.5)
16 (4.8, 56)

32. 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
940.6
80.5
137.4
25.0
aIC = 747.7
Note: All per 100,000 person-years.
aIC = adjusted interaction contrast; PTSD = posttraumatic stress disorder
Analyses adjusted for depression, anxiety disorders, and prior ISH.

33. 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
691.89
220.73
424.46
15.65
aIC = 62.35
Note: All per 100,000 person-years.
aIC = adjusted interaction contrast; PTSD = posttraumatic stress disorder
Analyses adjusted for depression, anxiety disorders, and prior ISH.

34. 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
700.03
86.33
375.75
18.38
aIC =
Note: All per 100,000 person-years
aIC = adjusted interaction contrast; PTSD = posttraumatic stress disorder
Analyses adjusted for depression, anxiety disorders, and prior ISH.

35. 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

36. 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

37. Future Directions and Summary
Novel methods
Machine learning
Sequence analysis
Multiple sources of data
Ultimate goal: better prediction and prediction tools

38. 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

39. Acknowledgements
This work was supported by grant YIG (PI: Gradus) from the American Foundation for Suicide Prevention and grant 1R01MH (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

40. 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,