Abstract 278: Using mHealth to Assess Physical Activity Guideline Adherence in Smokers: A Secondary Analysis of mActive-Smoke

Abstract

Background: Rates of cigarette smoking are decreasing due to public health initiatives, pharmacological aids, and clinician focus on smoking cessation. However, a sedentary lifestyle increases cardiovascular risk and therefore inactive smokers have a particularly enhanced risk of cardiovascular disease. We previously linked acute bouts of physical activity, but not total daily steps, to a decreased urge to smoke. In this secondary analysis, we investigate adherence to guideline-recommended moderate-vigorous physical activity (MVPA) in smokers and its association with urge to smoke. Methods: We enrolled 60 active smokers (≥3 cigarettes/day) and recorded free-living continuous step counts with the Fitbit Charge HR. MVPA was defined as cadence ≥100 steps/min. Participants were prompted to report instantaneous smoking urges via text message 3 times a day, on a Likert scale from 1 to 9. The Wilcoxon rank-sum test was used to test between-group differences in MVPA. A mixed-effects linear model for repeated measures, controlling for demographics and baseline activity level, was used to investigate the association between MVPA and urge. Results: Fifty-three participants (aged 40 ± 12 years, 57% [30/53] women, 49% [26/53] nonwhite, 38% [20/53] obese) recorded at least 6 weeks of data and were thus included; 3,633 days were analyzed, with a mean of 69 days per participant. Among all participants, median daily MPVA was 6 minutes (IQR 2-13), and this differed by sex (12 min [IQR 3-20] for men versus 3.5 min [IQR 1-9] for women, p=0.004) and BMI (2.5 min [IQR 1-8.25] for obese versus 10 min [IQR 3-15] for non-obese, p=0.035). The median daily MVPA minutes was poorly correlated with self-report via the International Physical Activity Questionnaire (Spearman’s coefficient -0.162, p=0.25). Thirty-one out of 53 (58%) participants ever obtained 30 min/day of MVPA over the study duration, and these 31 participants obtained 30 min/day MVPA on a mean of 19% of days. Only 15/53 (28%) participants met the national guidelines of 150 min/week of MVPA at least once throughout the study, and the median total MVPA per week was 80 minutes (IQR 31-162). Adjusted models showed no association between the number of MVPA minutes per day and mean daily smoking urge (p=0.72). Conclusion: In this 12-week study of adult smokers, the prevalence of MVPA was low and participants rarely met national guidelines for physical activity. Given poor attainment of guideline-recommended physical activity goals and the dual cardiovascular risk of inactivity and smoking, more work is required to address risk factors in smokers through promotion of physical activity.