Baseline comorbidity and CVD risk factors

The following baseline variables were examined from the electronic medical records: age, gender, body mass index (BMI), serum cholesterol concentration, and smoking status (defined as current smoker, ex-smoker or never smoker). Hypertension was defined as blood pressure (BP) greater than 140/90 mmHg and/or use of antihypertensive medication. CVD included coronary, cerebral, or peripheral artery diseases. An internist diagnosed coronary artery disease (CAD) by clinical symptoms and findings and/or exercise testing or coronary angiography. A neurologist confirmed the diagnosis of stroke by computerized tomography (CT) or magnetic resonance imaging (MRI). Peripheral artery disease was assessed by ankle-brachial index. Diagnosis of type 2 diabetes (T2D; fasting glucose of at least 7.0 mmol/l, use of insulin and/or oral antidiabetics) or impaired fasting glucose (IFG; fasting glucose of 6.1–6.9 mmol/l) was determined. Information of chronic obstructive pulmonary disease (COPD) diagnosed by a pulmonologist was derived from the electronic hospital records.