TABLE 6.

Sensitivity analysis with washout periods of risk of neuropsychiatric events in relation to leukotriene receptor antagonist (LTRA) use in patients with asthma or allergic rhinitis

	Total period				Observation period 1				Observation period 2
	Events (n)	Person-years	IRR (95% CI)	p-value	Events (n)	Person-years	IRR (95% CI)	p-value	Events (n)	Person-years	IRR (95% CI)	p-value
Primary analysis
Unexposed	21 028	49 546.89	1		5294	12 519.69	1		15 734	37 027.20	1
Exposed	571	1455.98	1.05 (0.96–1.15)	0.266	130	371.49	0.88 (0.73–1.06)	0.185	441	1084.50	1.11 (1.00–1.22)	0.047
Secondary analysis
Unexposed	19 827	47 394.77	1		5004	11 971.52	1		14 823	35 423.26	1
Exposed	571	1455.98	1.17 (1.06–1.27)	<0.001	130	371.49	0.98 (0.81–1.17)	0.797	441	1084.50	1.23 (1.11–1.36)	<0.001
Time since initiation of LTRA (days)
1–3	115	444.70	0.73 (0.61–0.88)	<0.001	28	107.86	0.69 (0.46–0.98)	0.052	87	336.85	0.74 (0.60–0.91)	0.006
4–7	180	228.38	2.25 (1.93–2.60)	<0.001	31	57.92	1.43 (0.98–2.01)	0.050	149	170.46	2.53 (2.14–2.97)	<0.001
8–14	133	221.99	1.71 (1.43–2.03)	<0.001	27	61.66	1.17 (0.78–1.69)	0.419	106	160.33	1.91 (1.57–2.31)	<0.001
15–30	66	244.77	0.76 (0.59–0.97)	0.016	20	68.13	0.78 (0.48–1.19)	0.280	46	176.64	0.75 (0.55–0.99)	0.050
31–90	51	219.15	0.66 (0.49–0.86)	<0.001	16	53.61	0.78 (0.45–1.25)	0.344	35	165.54	0.60 (0.42–0.83)	0.004
>90	26	96.99	0.78 (0.51–1.15)	0.241	8	22.30	1.01 (0.45–2.00)	0.970	18	74.69	0.71 (0.42–0.83)	0.168
Washout period (days)
1–3	198	363.44	1.54 (1.33–1.77)	<0.001	32	91.47	0.93 (0.64–1.29)	0.665	166	271.97	1.75 (1.50–2.04)	<0.001
4–7	331	460.87	2.03 (1.81–2.26)	<0.001	84	117.15	1.90 (1.51–2.35)	<0.001	247	343.71	2.06 (1.81–2.34)	<0.001
8–20	672	1327.81	1.42 (1.31–1.54)	<0.001	174	339.55	1.35 (1.15–1.57)	<0.001	498	988.26	1.44 (1.31–1.58)	<0.001

IRR: incidence rate ratio.