Effect of Nicotine on Negative Affect Among More Impulsive Smokers

In the present study, the authors tested the hypothesis that nicotine would provide greater relief from negative affect for more impulsive smokers than for less impulsive smokers. Euthymic adult smokers (N = 70) participated in 2 laboratory sessions, during which they underwent a negative mood induction (music x autobiographical memory), then smoked either a nicotinized or de-nicotinized cigarette. Mixed-effects regression yielded a significant Impulsivity x Condition (nicotinized vs. de-nicotinized) x Time interaction. Simple effects analyses showed that heightened impulsivity predicted greater negative affect relief after smoking a nicotinized cigarette but not after smoking a de-nicotinized cigarette. These data suggest that nicotine may be a disproportionately powerful negative reinforcer for highly impulsive smokers, promoting higher levels of nicotine dependence and inhibiting smoking cessation

Effects of Anacetrapib in Patients with Atherosclerotic Vascular Disease

BACKGROUND: Patients with atherosclerotic vascular disease remain at high risk for cardiovascular events despite effective statin-based treatment of low-density lipoprotein (LDL) cholesterol levels. The inhibition of cholesteryl ester transfer protein (CETP) by anacetrapib reduces LDL cholesterol levels and increases high-density lipoprotein (HDL) cholesterol levels. However, trials of other CETP inhibitors have shown neutral or adverse effects on cardiovascular outcomes. METHODS: We conducted a randomized, double-blind, placebo-controlled trial involving 30,449 adults with atherosclerotic vascular disease who were receiving intensive atorvastatin therapy and who had a mean LDL cholesterol level of 61 mg per deciliter (1.58 mmol per liter), a mean non-HDL cholesterol level of 92 mg per deciliter (2.38 mmol per liter), and a mean HDL cholesterol level of 40 mg per deciliter (1.03 mmol per liter). The patients were assigned to receive either 100 mg of anacetrapib once daily (15,225 patients) or matching placebo (15,224 patients). The primary outcome was the first major coronary event, a composite of coronary death, myocardial infarction, or coronary revascularization. RESULTS: During the median follow-up period of 4.1 years, the primary outcome occurred in significantly fewer patients in the anacetrapib group than in the placebo group (1640 of 15,225 patients [10.8%] vs. 1803 of 15,224 patients [11.8%]; rate ratio, 0.91; 95% confidence interval, 0.85 to 0.97; P=0.004). The relative difference in risk was similar across multiple prespecified subgroups. At the trial midpoint, the mean level of HDL cholesterol was higher by 43 mg per deciliter (1.12 mmol per liter) in the anacetrapib group than in the placebo group (a relative difference of 104%), and the mean level of non-HDL cholesterol was lower by 17 mg per deciliter (0.44 mmol per liter), a relative difference of -18%. There were no significant between-group differences in the risk of death, cancer, or other serious adverse events. CONCLUSIONS: Among patients with atherosclerotic vascular disease who were receiving intensive statin therapy, the use of anacetrapib resulted in a lower incidence of major coronary events than the use of placebo. (Funded by Merck and others; Current Controlled Trials number, ISRCTN48678192 ; ClinicalTrials.gov number, NCT01252953 ; and EudraCT number, 2010-023467-18 .)

Depression vulnerability within smoking research: How accurate are one-item screening items?

Epidemiological and large scale treatment studies within smoking research have utilized many one-item screening items to examine the influence of current depressive symptoms on smoking behavior and quitting. Little is known about that concurrent validity of screening items that may reflect depression vulnerability independent of current symptoms. The present paper evaluated the concurrent validity of two one-item screening items that were essential for diagnosing past episodes of major depression. Screening questions were administered to seventy seven nicotine dependent participants via a telephone screening interview. Smokers then returned to the laboratory for a comprehensive structured assessment of depressive vulnerability. Vulnerability measures were clinician diagnosed history of major depressive disorder and other self-reported depressive vulnerability factors. Telephone screening items accurately classified a clinician-diagnosed history of major depression, and predicted the number of recurrent depressive episodes, self-reported rumination, and self-reported depression-proneness (all p\u3c0.05). Results support the utility of one-item screening questions as a “proxy” of a depressive vulnerability for smoking treatment studies that are not designed for comprehensive assessment procedures

Infl uence of nicotine on positive affect in anhedonic smokers

Rationale – The possibility that individuals administer nicotine to self-regulate persistent negative affect has received interest as a possible explanation for the high prevalence of affectively vulnerable smokers. Relatively overlooked, however, is the possibility that smokers might also self-administer nicotine to elevate low positive affect. Objectives – This study examined whether nicotine administration augmented anhedonic smokers’ positive affective response to a positive mood induction. Materials and methods – Fifty regular smokers (50% female) underwent two positive mood inductions during which they smoked either a nicotinized or denicotinized cigarette in counterbalanced order. Positive affect was assessed before and at two time points after smoking. Results – Random effects regression showed a significant anhedonia by condition-by-time interaction [t (181) = −2.01, p = 0.04], supporting the hypothesis that anhedonia moderated nicotine’s effect on changes in positive affect. Simple effect analyses showed a significant condition-by-time interaction among high anhedonic smokers [t(91) = 2.47, p= 0.01] but not among less anhedonic smokers [t (91) = 0.34, p = 0.73]. Conclusion – Smoking nicotine vs placebo heightened anhedonic smokers’ ability to be induced into a positive mood, whereas nicotine had no effect on more hedonic smokers’ positive mood

Hedonic capacity, cigarette craving, and diminished positive mood

Cigarette craving has been linked to elevated negative and positive moods, but a connection to deficient positive affect has not been studied. We tested whether a low hedonic capacity predicts a heightened urge to smoke after acute nicotine deprivation, and whether such an effect is mediated by decreased positive mood or increased negative mood. A total of 35 smokers characterized for individual differences in hedonic capacity were deprived of nicotine for 48 hr. Using mixed-effects regression modeling, we found that lower hedonic capacity predicted greater increases in craving 24 hr after nicotine withdrawal, t(29)=-22.33, p=-.03. The effect of hedonic capacity on increased 24-hr postquit craving to smoke was fully mediated by decreased positive affect. Findings suggest that in early nicotine withdrawal, smokers with diminished capacity to experience pleasure have heightened susceptibility to cigarette cravings that arises because of decreased positive mood rather than increased negative mood

Reinforcement expectations explain the relationship between depressive history and smoking status in college students

Little is understood about biobehavioral mechanisms that mediate the comorbidity between cigarette smoking and depression. We hypothesized that expectancies about nicotine’s reinforcing effects are associated with vulnerability to depression, and may partially explain the relationship between history of depression and smoking. Young adult smokers and never smokers (N = 175, mean age = 19.9 years, S.D. = 3.2) were assessed for history of depression and expectations about the negative (e.g., dispels bad moods) and positive (e.g., increases pleasure) reinforcing effects of smoking. Results are inconsistent with the premise that negative reinforcement expectancies mediate the comorbidity between depression and nicotine dependence. Instead, findings suggest that young adults with a prior history of major depression hold exaggerated expectations about nicotine’s positive effects, which could enhance their likelihood of initiating smoking

Cue-Elicited Negative Affect in Impulsive Smokers

Impulsivity is associated with cigarette smoking, but the nature of this relationship and the mechanisms that maintain it are relatively unknown. The relationship has often been thought to reflect appetitive processes, but research suggests that an affective pathway exists as well. The present study tested the effect of impulsivity on affective responses to an environmental smoking cue. Adult smokers (N = 62) were exposed to a neutral cue and a smoking cue in separate experimental sessions in a repeated measures design. Mixed-effects regression analyses showed that larger postexposure increases in negative affect were associated with high scores on 2 facets of impulsivity: urgency, t(179) = 6.16, p \u3c .001, and sensation seeking, t(179) = 4.75, p \u3c .001. Heightened impulsivity was associated with lower levels of positive affect generally but not with positive affective responses to cue exposure. Findings provide support for the existence of a negative affective pathway linking impulsivity and cigarette smoking, and they suggest that this pathway may be specific to the urgency and sensation-seeking components of impulsivity