Table 2

CYP2C19 genotype associations with incident ischaemic stroke and MI events in patients prescribed clopidogrel

Outcome, model	CYP2C19 genotype	N	N cases	Person-years	HR	95% CIs	P value
Ischaemic stroke
All participants	Normal metaboliser (1/1)	5333	69	13 248
	Intermediate/poor (any 2-8)	2144	41	5110	1.53	1.04 to 2.26	0.031
	Total	7477	110	18 358
Events in first year only	Normal metaboliser (1/1)	5333	25	4419
	Intermediate/poor (any 2-8)	2144	14	1789	1.33	0.69 to 2.57	0.390
	Total	7477	39	6208
Events after first year only	Normal metaboliser (1/1)	3071	44	8829
	Intermediate/poor (any 2-8)	1245	27	3322	1.63	1.01 to 2.64	0.047
	Total	4316	71	12 151
MI
All participants	Normal metaboliser (1/1)	5259	1269	10 093
	Intermediate/poor (any 2-8)	2100	554	3709	1.14	1.04 to 1.26	0.008
	Total	7359	1823	13 803
Events in first year only	Normal metaboliser (1/1)	5255	906	3831
	Intermediate/poor (any 2-8)	2099	415	1511	1.16	1.03 to 1.31	0.011
	Total	7354	1321	5342
Events after first year only	Normal metaboliser (1/1)	2529	362	6258
	Intermediate/poor (any 2-8)	982	139	2198	1.09	0.90 to 1.33	0.370
	Total	3511	501	8455

Analysis of European-ancestry participants with >1 clopidogrel prescription in the available GP prescribing data. Participants excluded if clopidogrel prescribing frequency was less than once every 2 months. Events <1 week after first clopidogrel prescription are excluded. Events occurring after the last known date of clopidogrel prescription are also excluded. HRs from Cox’s proportional hazards regression models adjusted for age at first clopidogrel prescription, sex and genetic principal components of ancestry 1–10.
GP, general practitioner; MI, myocardial infarction.