1. Department of Hypertension and Diabetology; Medical University of Gdansk; Gdansk
2. Department of Internal Medicine and Diabetology; Medical University of Lodz; Lodz
3. Department of Internal Medicine, Hypertension and Vascular Disease; Medical University of Warsaw; Warsaw
4. Department of Diagnostics; Chair of Clinical Biochemistry; Jagiellonian University Medical College; Krakow Poland
5. Duke Clinical Research Institute; Biostatistics and Bioinformatics; Duke University; Durham NC USA