Long-Term Effectiveness of a Quitline for Smoking Cessation: Results of a Randomized Controlled Trial

Introduction: Smoking remains a significant global public health issue, leading to numerous preventable deaths and disabilities annually. Telephone counselling is a recommended intervention for smoking cessation, offering accessible support to a wide range of people who smoke. This study aimed to evaluate the long-term effectiveness of the German quitline for smoking cessation. Methods: A parallel-group, two-arm, superiority, randomized controlled trial was conducted between October 2021 and November 2023. People who smoked daily and were willing to quit received either up to six telephone counselling calls (intervention group) or a self-help brochure (control group). Seven-day point prevalence abstinence from cigarettes and tobacco at 12 months and prolonged cigarette and tobacco abstinence from 3 to 12 months after the start of the intervention were assessed. Further, the use of additional cessation aids was assessed. Results: A total of n = 905 participants were randomized (intention-to-treat sample). The intervention group (n = 477) exhibited higher rates of prolonged cigarette abstinence (31.7% vs. 17.8%) and prolonged tobacco abstinence (30.8% vs. 15.2%) compared to the control group (n = 428) at 12-month follow-up with corresponding odds ratios of 2.2 (95% CI [1.6, 3.0]) and 2.5 (95% CI [1.8, 3.5]). Seven-day point-prevalence cigarette abstinence was not statistically significant (OR = 1.3, 95% CI [1.0, 1.7]). E-cigarettes were the most commonly used additional cessation aid (46.0%), followed by electronic media (31.0%) and nicotine replacement therapy (26.2%). Conclusions: Telephone counselling provided by the national German quitline for smoking cessation demonstrates effectiveness in promoting long-term abstinence from cigarettes and tobacco. Increased awareness and use of the quitline could promote cessation rates in Germany. Given the rising popularity of novel nicotine consumer products, counselling protocols should incorporate information on their risks and potential as cessation tools.