Previously a number of factors have been shown to be associated both with occupational workload and BP. Thus, those factors will be included as covariates: sex (male or female) ; age (categories of <40, 50-59, 60-69, 70-79, and >80 years) ; body mass index (BMI; categories of <18.5, 18.5-24.9, 25.0-29.9, and ≥30kg/m2)  calculated from objectively measured body height and weight; smoking (categories of nonsmoking and currently smoking) ; length of education (categories of uneducated, low educated up to 3 years, vocationally educated 1-3 years, higher educated, and academically educated) ; for the prospective analysis only, additional adjustment for vital exhaustion, split in 4 categories defined elsewhere (0, 1-4, 5-9, and 10-17) ; self-rated cardiorespiratory fitness (categories of lower, similar, and higher cardiorespiratory fitness compared with peers of same sex and age) ; SBP at baseline (categories of 80-89, 90-99, 100-109, 110-119, 120-129, 130-139, and ≥140 mm Hg) ; and DBP at baseline (categories of 40-49, 50-59, 60-69, 70-79, 80-89, and ≥90 mm Hg).