Dental undergraduates' smoking status and social nicotine dependence in Japan and Taiwan: comparison between two dental schools

Objectives: Smoking behaviour persisted due to psychological and physical dependence. A questionnaire, "the Kano Test for Social Nicotine Dependence (KTSND)", has been developed to assess the persistence of tobacco use. This study aimed to investigate into the prevalence and factors of smoking in a sample of dental undergraduates in Japan and Taiwan. A special interest was to establish the association between gender, smoking status, relationship with smokers, as well as baseline and after-lecture KTSND scores. Methods: One hundred and thirty 4th year and forty-one 5th year dental undergraduates at the Aichi Gakuin University (AU, Japan; 85 males and 45 females; 21.7 ± 1.7 years) and the Kaohsiung Medical University (KU, Taiwan; 27 males and 14 females; 24.1 ± 2.1 years) were invited to participate, respectively. Each was assessed with a KTSND questionnaire before and after attending a tobacco-control educational programme. Results: Thirty-five smokers (20.5%, AU: 34, KU: 1), nine ex-smokers (5.2%, AU: 8, KU: 1) and 127 non-smokers (74.3%) were included. The prevalence of inhalation of second-hand smoke at home was 30.0% (39 students) and 18.2% (6 students) in Japan and Taiwan, separately. Japanese students showed a higher total KTSND score than Taiwanese (13.3 ± 6.4; 10.2 ± 4.9, P < 0.01). Attendance of the tobacco-control educational programme contributed to a decrease in the total KTSND score from 12.6 ± 6.2 to 7.7 ± 5.7. The total KTSND scores among smokers (17.4 ± 6.2) and ex-smokers (14.6 ± 4.5) were significantly higher than non-smokers' (11.1 ± 5.7) (P < 0.01). In Taiwan, male students demonstrated higher KTSND scores than their counterparts (11.3 ± 5.0; 8.1 ± 3.9, P < 0.05). Conclusion: The prevalence of smoking and the total KTSND scores among dental undergraduates were higher in Japan than in Taiwan. The total KTSND score was related to smoking status. Attendance of a tobacco-control educational programme decreased the total KTSND score. Future popularisation in the type of educational programme is indicated.