Objective
This study aims to assess differences in depressive and anxiety symptoms at 6-month follow-up in a smoking cessation trial using e-cigarettes as quitting aids.
Methods
We conducted a secondary analysis of the Swiss multicentre ESTxENDS smoking cessation randomized controlled trial (RCT) assessing differences in depressive (Patient Health Questionnaire-9, PHQ-9, range: 0–27) and anxiety symptoms (General Anxiety Disorder-7, GAD-7, range: 0–21) at 6-month follow-up comparing participants who received e-cigarettes to those who received smoking cessation counseling alone.
Results
Of 1244 participants 913 completed the PHQ-9 and 884 the GAD-7 at 6-month follow-up. Mean PHQ-9 scores (SD) at 6 months for the intervention group were 3.7 (3.9), control group: 4.0 (4.2); mean GAD-7 scores (SD) at 6 months for the intervention group were 4.6 (4.3), control group: 4.6 (4.4). Multivariable analyses showed no evidence of a clinically relevant intervention effect on the PHQ-9 [coefficient − 0.101, 95 % CI -0.182 to −0.019, p = .016, corresponding to a 0.9 decrease of the original PHQ-9 score] and the GAD-7 scores [coefficient − 0.056, 95 % CI -0.135 to 0.022, p = .160] in the main adjusted models.
Conclusions
Among smokers who participated in the ESTxENDS smoking cessation trial, we found distribution of e-cigarettes for smoking cessation in addition to standard counseling compared to counseling alone had no clinically relevant effect on depressive or anxiety symptoms at 6-month follow-up.
Trial Registration: ClinicalTrials NCT03603340