Table 2.

 Summary of characteristics of patients enrolled in 44 randomised controlled trials of varenicline

Characteristics of trial participants	No of trials
Smokers from general population	18
Smokers with psychiatric illness	8
Heavy drinking smokers/alcohol dependence	4
People dependent on cocaine or opioid dependent	3
Smokeless tobacco users	2
Smokers with mild to moderate COPD	1
Smokers with cardiovascular disease	1
Smokers about to undergo surgery	1
Patients with spinocerebellar ataxia type 3	1
Adolescent smokers	1
Elderly non-smokers	1
Smokers in hospital	1
Smokers previously treated with varenicline	1
Ex-smokers on long term NRT	1

COPD=chronic obstructive pulmonary disease; NRT=nicotine replacement therapy.