Table 2. Association between the use of TCA and SSRI and risk of glioma according to various exposure definitions.

	Cases	Controls	Crude ORa	Adjusted ORb
TCA
Never use	3630	72 152	1.00 (ref)	1.00 (ref)
Ever use	137	3188	0.85 (0.72–1.02)	0.89 (0.75–1.06)
Current/recent use	36	973	0.73 (0.52–1.03)	0.76 (0.55–1.07)
Past use	101	2215	0.91 (0.74–1.11)	0.95 (0.77–1.16)
Long-term use	13	373	0.69 (0.40–1.21)	0.72 (0.41–1.25)
Continuous long-term use	11	292	0.75 (0.41–1.36)	0.76 (0.42–1.40)
Cumulative duration
<1 year	109	2334	0.93 (0.76–1.13)	0.97 (0.80–1.18)
1–2 years	15	481	0.63 (0.37–1.05)	0.65 (0.39–1.09)
3–4 years	5	174	0.57 (0.23–1.39)	0.59 (0.24–1.44)
>5 years	8	199	0.81 (0.40–1.64)	0.83 (0.41–1.68)
SSRI
Never use	3336	66 118	1.00 (ref.)	1.00 (ref.)
Ever use	431	9222	0.92 (0.83–1.03)	0.95 (0.86–1.06)
Current/recent use	207	4043	1.01 (0.87–1.17)	1.04 (0.90–1.20)
Past use	224	5179	0.86 (0.75–0.99)	0.88 (0.76–1.01)
Long-term use	89	1932	0.90 (0.72–1.12)	0.93 (0.75–1.16)
Continuous long-term use	75	1534	0.95 (0.75–1.20)	0.98 (0.77–1.24)
Cumulative duration
<1 year	242	5266	0.91 (0.80–1.04)	0.93 (0.81–1.07)
1–2 years	100	2024	0.98 (0.80–1.20)	1.00 (0.81–1.23)
3–4 years	43	905	0.93 (0.68–1.27)	0.96 (0.70–1.30)
>5 years	46	1027	0.86 (0.64–1.17)	0.89 (0.66–1.20)

Abbreviations: OR=odds ratio; SSRI=selective serotonin reuptake inhibitor; TCA, tricyclic antidepressant.

Long-term use is defined as ⩾3 years of cumulative use.

In all analyses, prescriptions within the year prior to the index date were disregarded.

^aAdjusted for age and gender (by design; risk-set matching and conditional analysis).

^bFurther adjusted for (i) use (⩾2 prescriptions) of statins, anti-diabetics, low-dose aspirin, non-aspirin NSAIDs, inhibitors of the renin-angiotensin system, antihistamines, anti-asthma drugs, oral contraceptives, and hormonal replacement therapy; (ii) previous diagnoses of diabetes, stroke, allergy, and asthma; and (iii) highest achieved education.