Table 4.

 Risk of serious cardiovascular events* (other than major cardiovascular events) at six months follow-up in people using varenicline and bupropion to help with tobacco use cessation in nationwide registry based cohort study in Denmark, with follow-up from January 2007 to December 2010

Outcome event†	Person years	Events	Rate/1000 person years	Hazard ratio (95% CI)
Angina/ischaemic heart disease‡
Varenicline	8247	82	9.9	0.89 (0.66 to 1.20)
Bupropion	8386	93	11.1	1 (ref)
Heart failure
Varenicline	8264	13	1.6	0.82 (0.39 to 1.70)
Bupropion	8405	16	1.9	1 (ref)
Peripheral arterial disease§
Varenicline	8247	78	9.5	1.11 (0.81 to 1.54)
Bupropion	8392	71	8.5	1 (ref)
Transient ischaemic attack
Varenicline	8265	11	1.3	1.60 (0.62 to 4.13)
Bupropion	8409	7	0.8	1 (ref)
Cardiac arrhythmia¶
Varenicline	8263	20	2.4	0.64 (0.36 to 1.11)
Bupropion	8404	32	3.8	1 (ref)

*Matched for propensity score including all variables listed in table 1 and all estimable two way interactions between demographic and healthcare use variables. Study cohort included 35 858 patients, with new users of varenicline and bupropion matched 1:1 on propensity score and followed up to six months after start of treatment. Outcomes reported here were defined as secondary outcomes.

†Ascertained with data from National Patient Registry (inpatient admissions and emergency department visits).

‡Defined as diagnosis of angina/ischaemic heart disease or admission for coronary artery bypass grafting or percutaneous coronary intervention.

§Defined as diagnosis of peripheral arterial disease or procedure to treat peripheral arterial disease.

¶Includes atrial and ventricular arrhythmias but not conduction block.