Distinctive characteristics of methamphetamine users presenting at public clinics: steep rise in South Carolina, United States, 2000-2005.

BACKGROUND: Illicit methamphetamine use has risen dramatically over the last decade. We sought to examine methamphetamine use among individuals presenting for drug treatment in South Carolina, USA, to assess trends over time, correlates of methamphetamine use, and the relationship between methamphetamine use and functional/behavioral problems. METHODS: Data from 2000 to 2005 were obtained from a state-wide network of substance abuse clinics. We examined time trends, and compared sociodemographic characteristics and problems with daily functioning (Axis IV and Axis V disorders) of methamphetamine users vs. other drug users. RESULTS: Of 235,415 individuals presenting or being admitted to a clinic, 3526 reported illicit methamphetamine use. The prevalence of methamphetamine use as a presenting problem increased dramatically across the six-year period, especially in the rural Upstate region (0.4-6.1%). In comparison to other drug users presenting or admitted to treatment during this same time period, methamphetamine users were more likely to be female, between 20 and 40 years old, and non-Hispanic white ethnicity. In addition, more methamphetamine users had occupational (49% vs. 43%, p<0.001) or economic problems (41% vs. 35%, p<0.001), and problems with their primary support group (58% vs. 54%, p<0.05). However, the prevalence of Axis IV and Axis V problems were not statistically different between the two groups. CONCLUSIONS: The rapid escalation of methamphetamine use in South Carolina and elsewhere highlights the need for longitudinal studies to better understand the etiology and characteristics associated with methamphetamine uptake and addiction, and to develop the knowledge base required for more effective prevention and treatment.

Selectively reduced responses to smoking cues in amygdala following extinction-based smoking cessation: results of a preliminary functional magnetic resonance imaging study.

Preliminary studies suggest an extinction-based smoking cessation treatment using reduced nicotine content (RNC) cigarettes decreases self-report craving for cigarettes prior to quitting and may be an effective smoking cessation treatment. The aims of this study was to evaluate the effect of an extinction-based smoking cessation treatment on brain responses to smoking cues using blood-oxygen level-dependent (BOLD) functional magnetic resonance imaging (fMRI). Sixteen (n = 16) dependent smokers were scanned using BOLD fMRI at baseline, following 2-4 weeks of smoking RNC cigarettes while wearing a 21-mg nicotine patch, and 2-4 weeks following quitting smoking. During scanning, participants viewed smoking-related pictures (e.g. lit cigarette) and pictures of people engaged in everyday activities (e.g. using a stapler). Event-related BOLD responses to smoking and control cues were analyzed in regions of interest (ROIs) known to subserve reward, attention, motivation and emotion. The extinction-based treatment simultaneously attenuated responses to smoking cues in amygdala while potentiating responses to control cues. Exploratory analysis indicated that this pattern was also observed in the thalamus of future abstinent but not relapsing smokers. The results of this preliminary study suggest that an extinction-based treatment for smoking cessation alters brain responses to smoking and control cues in amygdala--a region previously associated with drug cue reactivity and extinction.

Transdermal nicotine attenuates depression symptoms in nonsmokers: a double-blind, placebo-controlled trial.

RATIONALE: Despite established links between nicotine dependence and depression, little research has examined the effects of nicotine on depression symptoms. OBJECTIVE: This study evaluated the acute and chronic effects of transdermal nicotine in nonsmokers with baseline depression symptoms during a 4-week, double-blind, placebo-controlled trial. METHODS: Nonsmokers with scores >or=10 on the Center for Epidemiological Studies Depression scale (CES-D) were recruited from the community. Mood and cognitive performance were measured at baseline (day 0) and at 1, 8, 21, and 28 days. Participants were randomly assigned to wear a placebo or nicotine patch for 4 weeks (3.5 mg/day during weeks 1 and 4; 7 mg/day during weeks 2 and 3). The final sample consisted of 11 nonsmokers with a mean baseline CES-D score of 27.36 (SD=10.53). RESULTS: Salivary nicotine levels indicated the majority of participants were compliant with treatment. Acute nicotine did not alter mood. After adjusting for baseline values, chronic nicotine resulted in a significant decline in CES-D scores at day 8 (3.5 mg/day), but returned to placebo levels by the last visit. This return to baseline levels was coincident with a decrease in nicotine administration from 7 to 3.5 mg/day. A similar trend for improved response inhibition as measured by the Conners Continuous Performance Task was also observed. Reported side effects were infrequent and minimal. CONCLUSION: These findings suggest a role for nicotinic receptor systems in the pathophysiology of depression and that nicotinic compounds should be evaluated for treating depression symptoms.

Abstinence-induced changes in self-report craving correlate with event-related FMRI responses to smoking cues.

Drug cues have been shown to activate brain regions involved in attention, motivation, and reward in addicted users. However, as studies have typically measured responses in only one state (ie drug abstinence), it is unclear whether observed activations represent amplification by abstinence or stable responses. Thus, the present study was designed to evaluate the stability of event-related responses to visual drug cues in dependent smokers (n=13) using event-related functional magnetic resonance imaging measures. Imaging was conducted following smoking as usual and following overnight abstinence, and self-reported craving measures were obtained before, during, and after scanning. Analysis of hemodynamic response (HDR) amplitudes in each of 13 regions of interest revealed larger responses to smoking compared to control cues in ventral anterior cingulate gyrus (vACG) and superior frontal gyrus. Responses to smoking cues in these and all other regions revealed no effects of abstinence/satiety, thus supporting the notion that cue-elicited brain responses are relatively stable. However, while the abstinence manipulation did not alter group-level responses to smoking cues, at the individual level, abstinence-induced changes in craving (abstinence minus satiety) were positively correlated with changes in HDR amplitude to smoking cues in frontal regions including left inferior frontal gyrus, left vACG, and bilateral middle frontal gyrus. These results suggest that brain responses to smoking cues, while relatively stable at the group level following short-term abstinence, may be modulated by individual differences in craving in response to abstinence-particularly in regions subserving attention and motivation.