Conflicts of interest

No conflict of interest exists regarding the present paper. Dr. Coghe received speaker fee from Teva, Almirall and Novartis and research grant from Novartis. Prof. Pau received speaker fee from Serono. Dr. Corona has nothing to disclose. Dr. Frau serves on scientific advisory boards for Biogen, received honoraria for speaking from Merck Serono and Teva and received a research grant from Serono. Dr. Fenu received honoraria for consultancy from Novartis and for speaking from Merck Serono and Teva, and received a research grant from Novartis. Dr. Lorefice received speaker fee from Teva and received a research grant from Serono Dr. Spinicci received speaker fee from Biogen. Dr Mamusa received speaker fee from Biogen. Dr. Musu received honoraria for consultancy and speaker fee from Biogen. Dr Massole received speaker fee from Biogen. Dr. Massa received speaker fee from Biogen. Professor Marrosu has received honoraria for consultancy or speaking from Bayer, Biogen-Idec, Novartis, Sanofi-Genzyme, Serono, Teva and Almirall. Prof. Cocco serves on scientific advisory boards and received honoraria for speaking from Bayer, Biogen, Merck Serono, Novartis, Sanofi-Genzyme and Teva.

Ethical standard

The study has been approved by the local ethic committee and has been performed in accordance with the ethical standards laid down in the 1964 Declaration of Helsinki and its later amendments.