Table 3.

Associations of pre-deployment insomnia with post-deployment suicidal ideation, adjusting for sociodemographic characteristics and prior deployment history (all models), pre-deployment risk factors (Models 2 and 3), and deployment experiences (Model 3 only)

	Full longitudinal sample (n = 4645)				Subsample without lifetime ideation at T0 (n = 4119)
	AOR	95% CI	χ2	P	AOR	95% CI	χ2	P
Insomnia disorder—Model 1	2.78	2.07% to 3.74%	46.22	<.0005	2.40	1.66% to 3.47%	21.41	<.0005
Insomnia disorder—Model 2	1.83	1.32% to 2.53%	13.06	<.0005	1.93	1.29% to 2.90%	10.15	.001
Insomnia disorder—Model 3	1.43	1.04% to 1.95%	4.91	.027	1.67	1.16% to 2.40%	7.57	.006

Weights-adjusted logistic regression models were fit to estimate the association of pre-deployment 30 day insomnia disorder with 30 day suicidal ideation at 3 or 9 months post-deployment (T2 or T3) among soldiers who completed surveys at all four waves (T0, T1, T2, and T3) of the Pre/Post Deployment Study (full longitudinal sample). Model 1 adjusted for age, sex, race, ethnicity, prior deployments, and BCT. Model 2 adjusted for the same variables as Model 1, plus suicidal ideation status at T0 (30 day ideation, lifetime but not 30 day ideation, or no lifetime ideation), lifetime TBI at T0, 30 day major depressive episode at T0, and 30 day GAD at T0. An interim model (results not presented) included all of the covariates from Model 2, plus deployment stress severity, deployment-acquired TBI, PTSD symptoms during deployment, and major depressive episode/GAD symptoms during deployment. Model 3 was identical to the interim model, except that nonsignificant pre-deployment risk factors and deployment experiences were excluded. An analogous procedure was used to estimate the association of pre-deployment insomnia disorder with incident suicidal ideation at T2 or T3 (subsample without lifetime suicidal ideation at T0).