Biomedical subjects

Dennis E McChargue

Publications and source records attributed to Dennis E McChargue.

11 recordsLinked to original sources

PubMed2006

Effect of tryptophan depletion on smokers and nonsmokers with and without history of major depression.

BACKGROUND: Serotonergic dysregulation is posited to contribute to comorbidity between nicotine dependence and depression. We tested whether acute tryptophan depletion (ATD) triggers depressive symptoms in euthymic, unmedicated smokers and nonsmokers with and without history of major depressive disorder (MDD). METHODS: Acute tryptophan depletion and taste-matched placebo challenges were administered double-blind in counter-balanced order. Participants were four groups of volunteers hypothesized to be of increasing affective vulnerability as follows: nonsmokers lacking recurrent personal and familial history of MDD (n = 20), smokers lacking recurrent personal and familial history of MDD (n = 21), nonsmokers with history of recurrent personal and familial MDD (n = 16), and smokers with recurrent personal and familial history of MDD (n = 16). Depression, dysphoric mood, and plasma amino acids were measured at baseline and around the time of peak depletion. RESULTS: Depressive symptom response to ATD was heightened significantly by history of MDD (p < .001) and marginally by smoking (p = .09). Smoking seemed to magnify the ATD response of those with a history of MDD (effect size = .63) but had no effect on those without MDD history (effect size = .06). CONCLUSIONS: Depressive symptom response to serotonergic challenge is exaggerated in unmedicated, euthymic adults with recurrent personal and familial vulnerability to MDD, perhaps especially if they also smoke.

Adolescent↗

PubMed2006

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<0.05). 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.

Adult↗

PubMed2006

Naltrexone renders one-session exposure therapy less effective: a controlled pilot study.

In vivo exposure has become the gold standard treatment for specific phobia. The endogenous opioid system is one mechanism proposed to explain why exposure provides such quick and effective treatment for specific phobia. The effect of naltrexone on fear and avoidance behavior was investigated among 15 specific phobia participants who received exposure treatment. Participants were randomly assigned to receive naltrexone, placebo, or no drug prior to attending one-session exposure treatment. Mixed effects regression results revealed that across time, the naltrexone group tolerated significantly less time in the room with the feared animal (Behavioral Avoidance Index) as compared to the placebo and no drug groups. Phobic individuals assigned to the naltrexone group had significantly higher fear ratings across time in comparison to the placebo group. Results provide support for the endogenous opioid system as a potential underlying biological mechanism associated with behavioral changes during in vivo exposure.

Adolescent↗

PubMed2004

Influence of fluoxetine on positive and negative affect in a clinic-based smoking cessation trial.

RATIONALE: Fluoxetine improves affect in clinical syndromes such as depression and premenstrual dysphoric disorder. Little is known about fluoxetine's influence on mood changes after quitting smoking, which often resemble sub-clinical depression. OBJECTIVES: The present study, a re-analysis of previously published data (Niaura et al. 2002), examined fluoxetine's effect on changes in negative and positive affect following quitting smoking. METHODS: Adult smokers (n=175) without clinically significant depression were randomized on a double-blind basis to receive fluoxetine hydrochloride (30 or 60 mg daily) or placebo for 10 weeks in combination with cognitive-behavioral therapy (CBT) for smoking cessation. We postulated that fluoxetine would beneficially influence post-cessation changes in positive and negative affect. RESULTS: Mood change across treatment was analyzed using mixed linear modeling controlling for initial level of nicotine dependence, plasma fluoxetine metabolites, and change in cotinine (a nicotine metabolite) at each visit. Relative to placebo, those on 60 mg fluoxetine experienced an elevation in positive affect that increased across time [t(526)=2.50, P=0.01], and a reduction in negative affect that returned to baseline across time [t(524)=2.26, P=0.02]. There were no differences between 30 mg and placebo on changes in positive or negative affect. CONCLUSIONS: Results indicate that 60 mg of fluoxetine improves both positive and negative mood states after quitting smoking and that diminished positive affect may be an overlooked affective response to smoking cessation.

Adult↗

PubMed2004

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.

Adult↗

PubMed2003

History of depression and smoking cessation outcome: a meta-analysis.

The authors conducted a meta-analysis of published studies to (a) evaluate the premise that a history of major depression is associated with failure to quit smoking and (b) identify factors that moderate the relationship between history of depression and cessation outcome. Fifteen studies met the selection requirements and were coded for various study methodology and treatment characteristics. DSTAT was used to calculate individual study effect sizes, determine the mean effect size across studies, and test for moderator effects. No differences in either short-term (< or = 3 months) or long-term abstinence rates (> or = 6 months) were observed between smokers positive versus negative for history of depression. Lifetime history of major depression does not appear to be an independent risk factor for cessation failure in smoking cessation treatment.

Adult↗

PubMed2003

Reward value of cigarette smoking for comparably heavy smoking schizophrenic, depressed, and nonpatient smokers.

OBJECTIVE: The study goal was to determine whether schizophrenic and depressed smokers perceive the reinforcement value of cigarette smoking differently from nonpsychiatric smokers who smoke as heavily. METHOD: The authors assessed the preferences for smoking cigarettes versus engaging in other pleasant activities, the perceived advantages and disadvantages of smoking, and the amount of reinforcement that would be needed to attain smoking abstinence among 26 schizophrenic, 26 depressed, and 26 nonpsychiatric heavy smokers. RESULTS: Both schizophrenic and depressed participants chose smoking as their preferred activity more often than nonpsychiatric smokers, and they did not differ from each other. The patients also exceeded the comparison group in the benefits they ascribed to smoking and felt they would require more incentives to quit, but they attributed comparable drawbacks to smoking. CONCLUSIONS: Schizophrenic and depressed smokers recognize many drawbacks associated with smoking, but compared to nonpatients who smoke as heavily, they also perceive more benefits and find cigarettes more appealing than alternative rewards. The heightened reward value of smoking warrants attention in tailoring tobacco control interventions for schizophrenic and depressed smokers.

Adult↗

PubMed2002

Would smokers with schizophrenia benefit from a more flexible approach to smoking treatment?

We evaluated literature that addresses the notion that flexible smoking treatment approaches are warranted for smokers with a diagnosis of schizophrenia. Understanding the biological and psychological mechanisms that increase the likelihood of smoking and decrease the motivation to quit for these individuals is addressed within the framework of a neurobiological model. We provide a brief overview of the limited smoking cessation treatment literature for patients with schizophrenia and compare abstinence-focused versus reduction-focused treatment modalities. The potential utility of the reduction-focused approach to tobacco treatment for these smokers is evaluated. Suggestions for future research to address the utility and efficacy of reduction-focused interventions for smokers with schizophrenia are put forth. We conclude with a consideration of the implications for the current understanding of smoking treatment among patients with co-morbid psychiatric diagnoses.

Drug Interactions↗

PubMed2002

Effect of non-nicotinic moist snuff replacement and lobeline on withdrawal symptoms during 48-h smokeless tobacco deprivation.

The present study investigated the effects of two herbal components (BACCOFF and DIPSTOP) of a commercially available smokeless tobacco treatment program for reducing subjective withdrawal symptoms during deprivation. One component, BACCOFF, is a non-nicotinic chew. The second component, DIPSTOP, is a liquid containing the alkaloid lobeline, which to some extent mimics peripheral nicotinic effects. All participants (N = 22 males) were placed in four conditions: BACCOFF + DIPSTOP, BACCOFF + placebo control, DIPSTOP, and placebo control only. The conditions involved 48 h of deprivation, and subjects were exposed to one condition per week for 4 weeks. Withdrawal measures were taken at baseline, 24 h, and 48 h of deprivation. Individuals were randomly assigned, and conditions were counterbalanced. Results showed that BACCOFF, as compared with DIPSTOP, significantly reduced withdrawal symptoms but not craving. These data suggest that behavioral/sensory substitutes' influence on withdrawal might be routed through the product's ability to approximate the preferred moist snuff.

Adolescent↗

PubMedDate not supplied

Attachment and depression differentially influence nicotine dependence among male and female undergraduates: a preliminary study.

The authors surveyed a convenience sample of 208 undergraduate students who reported that they smoked cigarettes. The primary hypothesis they tested was whether gender predicted nicotine dependence. They further tested whether depression and attachment would mediate or moderate this relationship. Hierarchical regression analyses with social desirability and smoking stage of change entered as covariates indicated that women exhibited greater nicotine dependence than men did (p < .01). Lower attachment scores fully mediated this relationship, whereas elevated depression scores moderated the relationship. These findings suggest that depression and the inability to bond with peers may promote nicotine dependence among young female students.

Adolescent↗

PubMedDate not supplied

Sun protection motivational stages and behavior: skin cancer risk profiles.

OBJECTIVE: To create skin cancer risk profiles that could be used to predict sun protection among Midwest beachgoers. METHOD: Cluster analysis was used with study participants (N=239), who provided information about sun protection motivation and behavior, perceived risk, burn potential, and tan importance. Participants were clustered according to their risk profiles; 4 distinct risk profiles emerged. RESULTS: Analyses revealed that risk profiles were significantly different on sun protection motivation and behavior and marginally different in terms of sun tanning behavior. CONCLUSION: Given the complexity of risk factors, an examination of clusters, rather than factors in isolation, may more accurately depict sun protection behavior.

Adult↗