1. From the Departments of Paediatrics (H.N., O.S.) and Medicine (J.V., T.R.), Research Centre of Applied and Preventive Cardiovascular Medicine (P.H., H.L.), and Turku Institute for Child and Youth Research (H.L.), University of Turku, Turku, Finland; National Public Health Institute (A.J.), Turku, Finland; and the Department of Paediatrics (E.J.), University of Helsinki, Helsinki, Finland.