Efficacy and utilization of an acceptance and commitment therapy-based smartphone application for smoking cessation among Black adults: secondary analysis of the iCanQuit randomized trial.

BACKGROUND AND AIMS

Black adults who smoke are less likely to seek treatment and to succeed in quitting compared with other racial groups. The lack of efficacious and engaging trials for smoking cessation further contributes to this disparity. This study explored whether an acceptance and commitment therapy (ACT)-based smartphone application (iCanQuit) was more efficacious for smoking cessation than a United States Clinical Practice Guidelines (USCPG)-based smartphone application (QuitGuide) among Black adults.

DESIGN

Secondary analysis of a two-arm randomized trial with 12-month follow-up.

SETTING

United States (US).

PARTICIPANTS

A total of 554 Black adults who smoke daily were recruited from 34 US states and enrolled between May 2017 and September 2018.

INTERVENTIONS

Participants were randomized to receive iCanQuit (n = 274) or QuitGuide (n = 280) for 12 months.

MEASUREMENTS

Smoking cessation outcomes were measured at 3, 6, and 12 months. The primary outcome was self-reported complete-case 30-day point prevalence abstinence (PPA) at 12 months. Secondary outcomes were 7-day PPA, missing-as-smoking imputation, multiple imputation, prolonged abstinence, and cessation of all tobacco products at 12 months. Study retention, treatment engagement, and change in ACT-based processes were also compared between arms.

FINDINGS

Study retention was 89% at 12 months and did not differ by arm (P > 0.05). The complete-case 30-day PPA was 28% for iCanQuit versus 20% for QuitGuide at 12 months (odds ratio [OR] = 1.60; 95% confidence interval [CI] = 1.03, 2.46). Similar associations were observed for the missing-as-smoking imputation, although non-significant (25% iCanQuit vs 18% QuitGuide; OR = 1.50; 95% CI = 0.98, 2.30). iCanQuit vs QuitGuide participants were significantly more engaged with iCanQuit application as measured by the number of logins from baseline to 6 months (incidence rate ratio = 3.26; 95% CI = 2.58, 4.13). Increased acceptance of cues to smoke mediated the effect of treatment on cessation (indirect effect: OR = 0.20; 95% CI = 0.05, 0.29).

CONCLUSIONS

Among Black adults, an acceptance and commitment therapy-based smartphone application appeared to be more efficacious and engaging for smoking cessation than the United States Clinical Practice Guidelines-based QuitGuide application.