Factors associated with persistent posttraumatic stress disorder among U.S. military service members and veterans

BMC Psychiatry

Table 2 Multivariable Regression Analysis of Predictors of Persistent PTSD at the First (2007–2008) and Second Follow-Ups (2011–2013)

	First Follow-Up (N = 2409) (47% With Persistent PTSD)		Second Follow-Up (N = 822) (71.2% With Persistent PTSD)
Characteristic*	OR	95% CI	OR	95% CI
Birth year
Prior to 1960	2.34	1.68–3.54	2.68	1.53–4.68
1960–1969	1.71	1.25–2.36	2.11	1.32–3.36
1970–1979	1.42	1.11–1.83	1.40	0.91–2.14
1980 or later	1.00		1.00
Pay grade
Junior enlisted (E1–E4)	2.10	1.50–2.93
Senior enlisted (E5–E9)	1.68	1.25–2.27
Officer	1.00
Deployment experience^a
Nondeployed	1.00		1.00
Deployed without combat	0.56	0.36–0.90	0.91	0.33–2.51
Deployed, low combat	0.73	0.53–1.00	1.77	0.90–3.50
Deployed, moderate combat	1.72	1.39–2.12	1.44	0.98–2.12
Deployed, high combat	3.91	2.56–5.96	2.63	1.27–5.42
PTSD severity at baseline^b
Per 10 point change in score	1.59	1.45–1.74	1.23	1.06–1.43
Multiple somatic symptoms score
< 15	1.00
≥ 15	1.47	1.18–1.83
Depression^c
No	1.00		1.00
Yes	1.50	1.23–1.83	2.33	1.63–3.33
Physical assault
No	1.00
Yes	1.25	1.01–1.54
Sleep duration
< 4 h per day			1.75	1.15–2.69
4–6 h per day			1.08	0.74–1.58
> 6 h per day			1.00
Separation from military
No			1.00
Yes			1.57	1.12–2.21
Social support
Not bothered/bothered a little			1.00
Bothered a lot			1.51	1.09–2.10
Disabling injury/illness
No	1.00
Yes	1.35	1.11–1.66

CI =confidence interval, OR =odds ratio, PHQ =Patient Health Questionnaire, PTSD =posttraumatic stress disorder
^aDeployments include those which occurred any time prior to the 2007 survey date and were in support of operations in Iraq and Afghanistan
^bPTSD severity at baseline was included as a continuous variable to adjust for varying PTSD scores. Results were modeled using a 10 point change in the severity score based on the standard deviation and what would be considered a clinically relevant change the PTSD score
^cDepression includes diagnosis by a medical professional or screening positive on the PHQ-9
*All variables with OR and 95% CI are significant at the alpha < 0.05 level

ISSN: 1471-244X