Table 4.

Incidence and HRs for suicide attempt stratified by the severity of TBI

Variables	N	Suicide attempts	Rate	Crude HR* (95% CI)	Adjusted HR* (95% CI)
Without TBI	70 016	314	0.29	1.00 (reference)	1.00 (reference)
Mild TBI	5319	37	0.93	3.06 (2.16 to 4.33)†	2.22 (1.56 to 3.17)†
Moderate TBI	11 661	111	0.98	3.21 (2.57 to 3.99)†	2.23 (1.77 to 2.82)†
Severe TBI	524	6	1.35	4.44 (1.98 to 9.97)†	2.32(1.03 to 5.26)‡

Rate, incidence rate in per 1000 person-years.

*Model adjusted for age, gender, income, urbanisation level and relevant comorbidities (hypertension, diabetes mellitus, hyperlipidaemia, coronary artery disease, congestive heart failure, liver cirrhosis, depression, tobacco use disorder and alcohol attributed disease).

†p<0.001; ‡p=0.044.

TBI, traumatic brain injury.