Factors associated with predictors of smoking cessation from a Norwegian internet-based smoking cessation intervention study.

Introduction: We examined if we could identify predictors for smoking cessation at six months post cessation, among smokers enrolled in a large Norwegian population-based intervention study.

Methods: We followed 4333 (72.1% women) smokers who enrolled in an internet-based smoking cessation intervention during 2010-2012. The baseline questionnaire collected information on sociodemographic and lifestyle factors, including current snus use. The cessation outcome was self-reported no smoking past seven days, at six months. We used logistic regression to estimate odds ratios (ORs) with 95% confidence intervals, to identify predictors of smoking cessation, adjusting for potential confounders.

Results: Women (OR=1.30; 95% CI: 1.01-1.69) compared with men, and those with medium (OR=1.31; 95% CI: 1.02-1.68) and longer (OR=1.42; 95% CI: 1.06-1.90) education compared with those with shorter education, were more likely to be successful quitters.Overall, being a student (OR=0.56; 95% CI: 0.37-0.85) compared with having full-time work, and a moderate to high Fagerström test for nicotine dependence (FTND) score (OR=0.69; 95% CI: 0.55-0.87) compared with a low score, were predictors for unsuccessful cessation. Current snus use was a predictor for unsuccessful cessation compared to no snus use for both men (OR=0.49; 95% CI: 0.28-0.88) and women (OR=0.49; 95% CI: 0.32-0.75).

Conclusions: Our study identifies female sex and longer education as predictors for successful smoking cessation, while a medium or high FTND score, being a student, and current snus use, were predictors for unsuccessful smoking cessation. Only current snus use was a predictor for unsuccessful cessation for both sexes. Our results indicate that smokers should be warned that snus use may prevent successful smoking cessation.