[1] Kuopio Univ Hosp, Dept Otorhinolaryngol, Inst Clin Med, FIN-70211 Kuopio, Finland
[2] Rinnekoti Res Ctr, Skogby Sleep Clin, Espoo, Finland
[3] Univ Helsinki, Dept Neurol, FIN-00014 Helsinki, Finland
[4] Natl Publ Hlth Inst, Dept Hlth Promot & Chron Dis Prevent, Helsinki, Finland
[5] Univ Kuopio, Sch Publ Hlth & Clin Nutr, FIN-70211 Kuopio, Finland
[6] Univ Helsinki, Dept Publ Hlth, Helsinki, Finland
[7] Kuopio Univ Hosp, Inst Clin Med Clin Physiol & Nucl Med, Kuopio, Finland
[8] Kuopio Univ Hosp, Inst Clin Med Resp Med, Kuopio, Finland
[9] Univ Kuopio, Dept Social Pharm, Ctr Pharmaceut Policy & Econ, FIN-70211 Kuopio, Finland