Table 1.

Definitions of Potential Risk Factor Variables

Variable	Definition
Current smoker	Tobacco smoking at the point of enrollment
Past smoker	Tobacco smoking in the past but in cessation at the point of enrollment
Never smoked	No tobacco smoking in the past
History of other ACE inhibitors	Taking other types of ACE inhibitors in the past
History of ACE inhibitor-induced cough	Experience of ACE inhibitor-induced cough in the past
History of ACE inhibitor-induced angioedema	Experience of ACE inhibitor-induced angioedema in the past
Hypertension	Clinical diagnosis with systolic blood pressure ≥140, diastolic blood pressure ≥90, or receiving anti-hypertensive therapy
Diabetes mellitus	Clinical diagnosis with educational or pharmacological therapy
Coronary artery disease	Typical angina or myocardial infarction diagnosed by electrocardiogram or coronary angiography
Congestive heart failure	Clinical diagnosis or left ventricular ejection fraction ≤40%
Chronic obstructive pulmonary disease	Clinical diagnosis, typical chest radiograph findings, or FEV1.0 ≤70%
Asthma	Clinical diagnosis with history of use of inhalers, aminophyline, or steroids
Other respiratory diseases	Any kind of lung parenchymal disease documented by physician
Depression/anxiety	Clinical diagnosis or use of antidepressant
Other psychiatric diseases	Any kind of psychiatric disease documented by physician
Hemodialysis	On hemodialysis or peritoneal dialysis at the point of enrollment
Creatinine	Creatinine value (mg/dL) just before enrollment. If none available, closest value before the end of study
Concurrent medications	Prescription of the subsequent drugs at the point of enrollment
Diuretics	Any kind of loop diuretics, thiazide, or derivatives
Beta-blockers	Any kind of beta-blocking agents including alpha/beta-blocking agents
Calcium antagonists	Any kind of calcium antagonists
Low dose (≤325 mg/day) aspirin	Aspirin prescribed ≤325 mg/day
High dose (≥325 mg/day) aspirin	Aspirin prescribed >325 mg/day
Nonsteroidal anti-inflammatory drugs	Any kind of nonsteroidal anti-inflammatory drugs except for aspirin and cyclo-oxygenase-2 inhibitors
Cyclo-oxygenase-2 inhibitors	Any kind of cyclo-oxygenase-2 inhibitors

ACE, angiotensin-converting enzyme; FEV, forced expiratory volume.