Table 4.

Risk of Stroke by TBI Severity.

	Veterans Without TBI	Veterans With Mild TBI	Veterans With Moderate or Severe or Penetrating TBI
Any Stroke
No. Events/No. PYs	10,297/1,811,490	6,744/791,250	8,767/607,738
Unadjusted Incidence Rate per 1,000 PYs (95% CI)	5.7 (5.4, 6.0)	8.5 (8.1, 9.0)	14.4 (13.7, 15.2)
Adjusted* Cox proportional hazards model, HR (95% CI)	1 (Reference)	1.59 (1.54-1.64)	2.18 (2.11-2.24)
Adjusted* Fine-Gray proportional hazards model, HR (95% CI)	1 (Reference)	1.47 (1.43-1.52)	2.02 (1.96-2.09)
Ischemic Stroke
No. Events/No. PYs	9,924/1,812,455	6,323/792,827	7,585/613,534
Unadjusted Incidence Rate per 1,000 PYs (95% CI)	5.5 (5.2, 5.7)	8.0 (7.5, 8.4)	12.4 (11.7, 13.1)
Adjusted* Cox proportional hazards model, HR (95% CI)	1 (Reference)	1.55 (1.50-1.60)	1.92 (1.7-1.99)
Adjusted* Fine-Gray proportional hazards model, HR (95% CI)	1 (Reference)	1.43 (1.38-1.48)	1.78 (1.73-1.84)
Hemorrhagic Stroke
No. Events/No. PYs	660/1,848,365	637/814,134	1,671/638,374
Unadjusted Incidence Rate per 1,000 PYs (95% CI)	0.4 (0.3, 0.4)	0.8 (0.6, 0.9)	2.6 (2.3, 2.9)
Adjusted* Cox proportional hazards model, HR (95% CI)	1 (Reference)	2.23 (1.99-2.50)	6.45 (5.87-7.09)
Adjusted* Fine-Gray proportional hazards model, HR (95% CI)	1 (Reference)	2.11 (1.88-2.36)	6.14 (5.58-6.76)

^*Model adjusted for demographics (age, sex, race/ethnicity, income, education, and current smoking), medical comorbidities (hypertension, hyperlipidemia, diabetes, coronary artery disease, and atrial fibrillation) and psychiatric comorbidities (post-traumatic stress disorder and depression).