Concurrent E-Cigarette Use During Tobacco Dependence Treatment in Primary Care Settings: Association With Smoking Cessation at Three and Six Months.

INTRODUCTION: Electronic cigarettes (e-cigarettes) are being used as cessation aids by many smokers despite a lack of empirical evidence regarding their safety and efficacy. We analyzed the association of e-cigarette use and smoking abstinence in a population of smokers accessing standard smoking cessation treatment (nicotine replacement therapy [NRT] plus behavioral counseling) through primary care clinics in Ontario, Canada. METHODS: Participants were recruited through 187 primary care clinics across Ontario, Canada and were eligible for up to 26 weeks of brief behavioral counseling and individualized dosing of NRT at no cost. Adjusted logistic regression models were used to examine the association between concurrent e-cigarette use and smoking abstinence at 3- and 6-month follow-ups. RESULTS: Of the 6526 participants who completed a 3-month follow-up, 18.1% reported using an e-cigarette while in treatment. The majority of e-cigarette users (78.2%) reported using an e-cigarette for smoking cessation. At 3-month follow-up, e-cigarette use was negatively associated with abstinence after controlling for confounders (adjusted odds ratio [AOR] = 0.706, p < .001, 95% confidence interval [CI] = 0.607-0.820). E-cigarette use was also negatively associated with abstinence at 6-month follow-up (AOR = 0.502, p < .001, 95% CI = 0.393-0.640). CONCLUSION: E-cigarette use was negatively associated with successful quitting in this large community sample of smokers accessing standard evidence-based smoking cessation treatment through primary care clinics, even after adjusting for covariates such as severity of tobacco dependence, gender, and age. The findings suggest that concurrent use of e-cigarettes with NRT may harm cessation attempts. IMPLICATIONS: This study confirms previous findings from observational studies regarding the negative association between e-cigarette use and smoking cessation, but in a large cohort of smokers enrolled in an evidence-based treatment program. The implications of these findings are that concurrent use of e-cigarettes during a quit attempt utilizing cost-free evidence-based treatment (NRT plus behavioral counseling) does not confer any added benefit and may hamper successful quitting.

High-fat feeding does not induce an autophagic or apoptotic phenotype in female rat skeletal muscle.

Apoptosis and autophagy are critical in normal skeletal muscle homeostasis; however, dysregulation can lead to muscle atrophy and dysfunction. Lipotoxicity and/or lipid accumulation may promote apoptosis, as well as directly or indirectly influence autophagic signaling. Therefore, the purpose of this study was to examine the effect of a 16-week high-fat diet on morphological, apoptotic, and autophagic indices in oxidative and glycolytic skeletal muscle of female rats. High-fat feeding resulted in increased fat pad mass, altered glucose tolerance, and lower muscle pAKT levels, as well as lipid accumulation and reactive oxygen species generation in soleus muscle; however, muscle weights, fiber type-specific cross-sectional area, and fiber type distribution were not affected. Moreover, DNA fragmentation and LC3 lipidation as well as several apoptotic (ARC, Bax, Bid, tBid, Hsp70, pBcl-2) and autophagic (ATG7, ATG4B, Beclin 1, BNIP3, p70 s6k, cathepsin activity) indices were not altered in soleus or plantaris following high-fat diet. Interestingly, soleus muscle displayed small increases in caspase-3, caspase-8, and caspase-9 activity, as well as higher ATG12-5 and p62 protein, while both soleus and plantaris muscle showed dramatically reduced Bcl-2 and X-linked inhibitor of apoptosis protein (XIAP) levels. In conclusion, this work demonstrates that 16 weeks of high-fat feeding does not affect tissue morphology or induce a global autophagic or apoptotic phenotype in skeletal muscle of female rats. However, high-fat feeding selectively influenced a number of apoptotic and autophagic indices which could have implications during periods of enhanced muscle stress.