Traumatic Brain Injury and Substance Related Disorder: A 10-Year Nationwide Cohort Study in Taiwan

Table 4

Incidence and hazard ratios for substance related disorder stratified by the severity of TBI.

Variables		Substance related disorder	Rate	Crude HR (95% CI)	Adjusted HR (95% CI)
Without TBI	19109	118	0.41	1.00 (reference)	1.00 (reference)
Mild TBI	5757	79	1.84	8.73 (6.25–12.19)	5.50 (3.89–7.78)
Moderate TBI	12786	245	1.97	9.23 (6.31–13.48)	6.50 (4.41–9.58)
Severe TBI	566	16	3.31	19.14 (10.75–34.05)	9.01 (4.97–16.33)

Rate, incidence rate per 1000 person-years; 95% CI, 95% confidence interval; HR, hazard ratio; TBI, traumatic brain injury.
Model adjusted for age, gender, income, urbanization level, Charlson Comorbidity Index, and relevant comorbidities (hypertension, diabetes mellitus, hyperlipidemia, coronary artery disease, congestive heart failure, chronic obstructive pulmonary disease, and malignancy).
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