1. Department of Occupational, Metabolic and Internal Diseases, Medical University of Gdańsk, ul. Powstania Styczniowego 9B, 81-516 Gdynia, Poland
2. Department of Preventive Medicine and Education, Medical University of Gdańsk, 80-211 Gdańsk, Poland
3. Department of Internal Medicine and Gerontology, Jagiellonian University Medical College, 31-107 Kraków, Poland
4. Department of Cardiology, Congenital Heart Disease and Electrotherapy, Silesian Center for Heart Disease, 41-800 Zabrze, Poland