Impact of reduced nicotine content on behavioral economic measures of cigarette reinforcement in adolescents who smoke cigarettes.

BACKGROUND: Public health officials in the U.S. and New Zealand are considering a reduced nicotine standard for cigarettes to reduce their addictive potential. This study's aim was to evaluate the effects of nicotine reduction on the reinforcing efficacy of cigarettes in adolescents who smoke, which has implications for this policy's potential for success. METHODS: Adolescents who smoked cigarettes daily (n = 66; mean age: 18.6) participated in a randomized clinical trial assessing effects of assignment to very low nicotine content (VLNC; 0.4 mg/g nicotine) or normal nicotine content (NNC; 15.8 mg/g nicotine) cigarettes. Hypothetical cigarette purchase tasks were completed at baseline and the end of Week 3 and demand curves fit to the data. Linear regressions estimated effects of nicotine content on demand for study cigarettes at baseline and Week 3 and associations between baseline demand for cigarette consumption at Week 3. RESULTS: An extra sum of squares F-test of fitted demand curves indicated that demand (α) was more elastic among VLNC participants at baseline and Week 3 (F(2, 1016)= 35.72, p < 0.001). Adjusted linear regressions indicated demand was more elastic (ß= 1.45, p < 0.01) and maximum expenditure (Omax) lower (ß= -1.42, p-0.03) among VLNC participants at Week 3. More elastic demand for study cigarettes at baseline predicted lower consumption of cigarettes at Week 3 (p's < 0.01). CONCLUSIONS: A nicotine reduction policy may reduce the reinforcing value of combustible cigarettes among adolescents. Future work should investigate likely responses to such a policy among youth with other vulnerabilities and evaluate the potential for substitution to other nicotine containing products.

TB preventive treatment among pregnant women with HIV.

BACKGROUND: The WHO recommends TB preventive treatment (TPT) for people living with HIV, including pregnant women. Uptake of this policy recommendation in this subpopulation and country alignment with WHO guidance is unclear.METHODS: We conducted a policy review in 38 WHO high TB and TB-HIV burden countries to assess if the uptake of TPT policy among pregnant women living with HIV was in line with the WHO´s 2018 Updated and Consolidated Guidelines for Programmatic Management for LTBI. Data sources included TB national guidelines and HIV/AIDS/ART national guidelines, complemented by results from a previous survey on policy uptake held at the WHO.RESULTS: Uptake of WHO policy to provide TB preventive treatment among women with HIV accessing antenatal care was moderate: 64% (23 of 36 countries) explicitly recommended at least one clinical guideline or policy recommendation on screening, testing or treatment of LTBI among pregnant women living with HIV. There was considerable variation between countries on the stages in pregnancy that TPT should be provided. Two countries (5%) provided clinical monitoring recommendations for pregnant women.CONCLUSIONS: There is moderate uptake of TPT policy for pregnant women with HIV. Failure to provide TPT as part of antenatal or prevention of mother-to-child services is a missed opportunity for TB control.

Associations Between Nicotine Knowledge and Smoking Cessation Behaviors Among US Adults Who Smoke.

INTRODUCTION: Misperceptions about nicotine's contribution to smoking-related health harms could complicate efforts to reduce the public health burden of smoking. Study goals were to describe nicotine knowledge among adults who smoke and investigate whether misperceiving nicotine as a source of health harm was associated with beneficial health behaviors, or lower uptake of using less harmful sources of nicotine to support smoking cessation attempts. METHOD: This study used longitudinal data from 9140 adults who participated in four waves of the Population Assessment of Tobacco and Health Study and were current smokers during the first wave. Logistic regressions estimated odds ratios for correct responses across six aspects of nicotine knowledge assessed in Wave 4. Longitudinal models estimated associations between misperceptions and cigarette consumption, and odds of making a quit attempt; self-reported cessation; e-cigarette use; and use of NRT or e-cigarettes to support quit attempts. RESULTS: Participants who were non-White, older, and had lower educational attainment or income tended to be least knowledgeable about nicotine. Misperceiving nicotine as harmful to health was associated with increased odds of quit attempts (AOR: 1.12, 95% CI: 1.03, 1.23), lower odds of cessation success (AOR: 0.84, 95% CI: 0.73, 0.98) and e-cigarette use (AOR: 0.79, 95% CI: 0.72, 0.86), and lower odds of using NRT (AOR: 0.84, 95% CI: 0.71, 0.99) or e-cigarettes to support quit attempts (AOR: 0.59, 95% CI: 0.49, 0.71). CONCLUSION: Harm reduction efforts may be impeded by misperceptions about nicotine. Further work should evaluate the effects of correcting such misperceptions through public education. IMPLICATIONS: This study provides longitudinal evidence that among adult smokers, misperceiving nicotine as a primary cause of smoking-related diseases may be associated with reduced cessation success and lower likelihood of using less harmful nicotine products. These misperceptions may therefore impede efforts to encourage smokers ready to quit to use evidence-based cessation support such as nicotine replacement during quit attempts and limit the success of policies designed to shift smokers to less harmful sources of nicotine. Further work should evaluate the longitudinal effects of correcting nicotine misperceptions through public education targeted toward adults who smoke.