Table 3

Incidence of anxiety disorders in traumatic brain injury patients stratified by age group

	TBI with hyperlipidaemia				TBI without hyperlipidaemia				IRR* (95% CI)	Adjusted† HR (95% CI)
	N	ADs	PY	Rate	N	ADs	PY^#	Rate	IRR* (95% CI)	Adjusted† HR (95% CI)
Age <35
Total	82	7	651.46	107.45	164	8	1335.06	59.92	1.79 (0.65 to 4.94)	2.63 (0.58 to 4.71)
Male	72	7	591.77	118.29	144	8	1217.52	65.71	1.80 (0.65 to 4.96)	1.00 (ref.)
Female	10	0	59.69	0.00	20	0	117.53	0.00	N/A<always NA>	N/A
Age: 35–50
Total	274	29	1779.58	162.96	548	36	3657.26	98.43	1.66 (1.02 to 2.70)^$	1.42 (0.82 to 2.47)
Male	208	16	1359.21	117.72	417	18	2751.44	65.42	1.80 (0.92 to 3.53)	1.00 (ref.)
Female	66	13	420.36	309.26	131	18	905.82	198.72	1.56 (0.76 to 3.18)	2.81 (1.73 to 4.58)^‡
Age: 50–65
Total	399	53	2128.21	249.04	797	53	4471.10	118.54	2.10 (1.44 to 3.07)^‡	2.54 (1.68 to 3.83)^‡
Male	249	20	1344.10	148.80	495	23	2752.23	83.57	1.78 (0.98 to 3.24)	1.00 (ref.)
Female	150	33	7847.11	420.86	302	30	1718.87	174.53	2.41 (1.47 to 3.95)^‡	2.44 (1.65 to 3.60)^‡
Age: >65
Total	519	48	2658.16	180.58	1039	80	5426.74	147.42	1.22 (0.86 to 1.75)	1.13 (0.77 to 1.67)
Male	331	27	1630.31	165.61	664	44	3276.11	134.31	1.23 (0.76 to 1.99)	1.00 (ref.)
Female	188	21	1027.85	204.31	375	36	2150.63	167.39	1.22 (0.71 to 2.09)	1.30 (0.92 to 1.85)

*Estimated with Poisson regression.
†The model was adjusted by gender, hypertension, diabetes mellitus and cardiovascular disease.
^‡p<0.001; ^$p<0.05.
ADs, anxiety disorders; IR, incidence rate, per 10 000 person-years; IRR, incidence rate ratio; N/A, not available; PY, person-year; ref., reference group; TBI, traumatic brain injury.