1. Unit of Cardiovascular and Nutritional Epidemiology, Institute of Environmental Medicine, Karolinska Institutet , Nobels Vãg 13 , Stockholm 171 77, Sweden
2. Research Unit for Epidemiology, Department of Public Health, Aarhus University , Bartholins Allé 2, 8000 Aarhus C, Denmark
3. Department of Epidemiology, University of Alabama at Birmingham , Ryals Public Health Building (RPHB), 1665 University Boulevard, Birmingham, Alabama 35233, USA
4. Division of Cardiovascular Medicine, Department of Medicine, Karolinska Institutet , Solna Karolinska University Hospital D1:04, 171 76 Stockholm, Sweden
5. Unit of Medical Epidemiology, Department of Surgical Sciences, Uppsala University , Akademiska sjukhuset ingång 78, 751 85 Uppsala, Sweden