Riccardo Polosa1,2,3,4. 1. Department of Clinical and Experimental Medicine, University of Catania, Catania, Italy. polosa@unict.it. 2. Centre for the Prevention and Treatment of Tobacco Addiction (CPCT), Teaching Hospital "Policlinico - V. Emanuele", University of Catania, Catania, Italy. polosa@unict.it. 3. Center of Excellence for the Acceleration of Harm Reduction (CoEHAR), Università di Catania, Catania, Italy. polosa@unict.it. 4. UOC Medicina Interna e Urgenza, AOU "Policlinico - V. Emanuele - San Marco", via S. Sofia, 78 - Ed. 4, p. 2, stanza 78, 95100, Catania, Italy. polosa@unict.it.