Comprehensive Baseline Questionnaire for CVD

The baseline questionnaire (Q_0) included 554 questions about a wide array of characteristics: socio-demographic (e.g. sex, age and marital status), anthropometric (e.g. weight and height, weight gain in the past five years), lifestyle and health-related habits (e.g. smoking status, physical activity), diet (e.g. energy and alcohol intakes), employment status (e.g. employed/unemployed and working hours/week), obstetric history for women (e.g. pregnancy) and medical history (e.g. prevalence of chronic diseases and medication use). Total energy and alcohol intakes were ascertained through a semi-quantitative food frequency questionnaire (136 food items) previously validated in Spain [26 (link)]. Physical activity was collected through a validated questionnaire that included information about 17 activities such as walking, running, cycling, swimming, judo, soccer, skiing or sailing. To quantify the volume of activity during leisure time, an activity metabolic equivalent (MET) index was computed by assigning a multiple of resting metabolic rate (MET score) to each activity [27 (link)], and the time spent in each of the activities was multiplied by the MET score specific to each activity, and then summed the overall activities obtaining a value of overall weekly MET-hours. Leisure time physical activity estimated with the questionnaire was previously validated by our group using a tri-axial accelerometer as the gold standard. Physical activity during leisure time (estimated as MET-h/week) derived from the questionnaire moderately correlated with Kcal/day assessed through the accelerometer (Spearman's rho = 0.507, 95% CI: 0.232 – 0.707, p < 0.001) [28 (link)].
Participants were classified as having cardiovascular disease at baseline or at follow-up if they reported at least one of the following conditions: myocardial infarction, stroke, atrial fibrillation, paroxysmal tachycardia, coronary artery bypass grafting or other revascularization procedures, heart failure, aortic aneurism, pulmonary embolism, or peripheral venous thrombosis. Information regarding cancer both at baseline and during follow-up was also collected.