Effects of nicotine withdrawal on panic-like response to breath holding: a placebo-controlled, double-blind, crossover patch study

BACKGROUND

Cigarette smoking may increase the likelihood of developing panic disorder. Periods of nicotine withdrawal, in particular, may promote panic in individuals high in anxiety sensitivity. We examined the importance of nicotine withdrawal in the occurrence of smoking and panic.

METHODS

We utilized a placebo-controlled, double-blind, randomized, crossover design. Fifty smokers underwent a breath-holding (BH) challenge after the transdermal administration of nicotine on one test day and a placebo on another test day. Physiological and psychological variables were assessed at baseline as well as directly before and after the challenges.

RESULTS

Nicotine abstinence induced a decrease in heart rate and systolic blood pressure (BP) before the BH procedure (heart rate: 78.80 ± 11.43 under nicotine, 70.88 ± 10.83 under placebo; systolic BP: 124.90 ± 11.34 under nicotine, 121.18 ± 13.44 under placebo) and shorter BH duration relative to the nicotine patch condition. Nicotine abstinence did not, though, increase fear reactivity to the challenge.

CONCLUSIONS

The findings for heart rate and BP are consistent with the stimulant properties of nicotine. The reduced capacity to maintain apnea under placebo might be due to carbon dioxide (CO2 ) hypersensitivity during periods of nicotine abstinence. The negative findings regarding fear reactivity might be due to BH being a relatively weak anxiogen. Future researchers are encouraged to employ CO2 -inhalation procedures to study the relationship between nicotine withdrawal and panic.

Dynamic modulation of spatially structured polarization fields for real-time control of ultrafast laser-material interactions

The polarization state of an ultrafast laser is dynamically controlled using two Spatial Light Modulators and additional waveplates. Consequently, four states of polarization, linear horizontal and vertical, radial and azimuthal, all with a ring intensity distribution, were dynamically switched at a frequency ν = 12.5 Hz while synchronized with a motion control system. This technique, demonstrated here for the first time, enables a remarkable level of real-time control of the properties of light waves and applied to real-time surface patterning, shows that highly controlled nanostructuring is possible. Laser ablation of Induced Periodic Surface Structures is used to directly verify the state of polarization at the focal plane.

What is the clinical effectiveness and cost-effectiveness of using drugs in treating obese patients in primary care? A systematic review

BACKGROUND

Obesity [defined as a body mass index (BMI) ≥ 30 kg/m(2)] represents a considerable public health problem and is associated with a significant range of comorbidities and an increased mortality risk. The primary aim of the management of obesity is to achieve weight reduction in the interests of health. For obese patients who cannot achieve or maintain a healthy weight by non-pharmacological means, drug therapy is recommended in combination with non-pharmacological interventions such as dietary modifications and exercise.

OBJECTIVE

To evaluate the clinical effectiveness and cost-effectiveness of three pharmacological interventions in obese patients.

DATA SOURCES

Clinical effectiveness data used in the meta-analysis were sourced from articles identified in a systematic review of the literature. Data used to inform transitions to obesity-related comorbidities were derived from the General Practice Research Database (GPRD). The results of the meta-analysis and GPRD analyses informed the economic model supplemented by data from the Health Survey for England and other UK-specific data sourced from the literature.

REVIEW METHODS

A systematic literature review was conducted of the clinical effectiveness and cost-effectiveness of orlistat, sibutramine and rimonabant within their licensed indications for the treatment of obese patients. Electronic bibliographic databases including MEDLINE, MEDLINE In-Process & Other Non-Indexed Citations, EMBASE, The Cochrane Library databases and Cumulative Index to Nursing and Allied Health Literature (CINAHL) were searched in January 2009, and the reference lists of relevant articles were checked. Studies were included if they compared orlistat, sibutramine or rimonabant with lifestyle and/or exercise advice (standard care), placebo or metformin.

RESULTS

Overall, 94 studies involving 24,808 individuals were included in the clinical meta-analysis. Eighty-three trials included data on weight change, 41 included data on BMI change and 45 and 36 studies reported on 5% and 10% body weight loss, respectively. Overall, the results show that the active drug interventions are all effective at reducing weight and BMI compared with placebo. In the case of sibutramine, the higher dose (15 mg) resulted in a greater reduction than the lower dose (10 mg). Generally, the data quality of the trials included was low with poor reporting of standard errors and standard deviations. Results from the BMI risk models derived from the GPRD showed consistent increases in risk with increasing BMI. Adjustments for key confounders, such as age, sex and smoking status, were found to be statistically significant at the 5% level, in all risk models. Applying linear models to estimate BMI trajectories, for the diabetic cohort, an average increase in BMI of 0.040 per year for both men and women was observed. The non-diabetic cohort model showed an increase in BMI of 0.175 per year for women and 0.145 per year for men. The results of the cost-effectiveness analyses suggest that sibutramine 15 mg dominates the other three active interventions and the net benefit analyses show that sibutramine 15 mg is the most cost-effective alternative for thresholds > £2000 per quality-adjusted life-year (QALY). However, both sibutramine and rimonabant have been withdrawn because of safety concerns relating to potential treatment-induced fatal adverse events. If the proportion of patients who experienced a fatal adverse event was > 1.8% (1.5%, 1.0%) for sibutramine 15 mg (sibutramine 10 mg, rimonabant) the treatment would not be considered cost-effective when using a threshold of £20,000 per QALY.

LIMITATIONS

The clinical review did not include all possible lifestyle comparators, with the inclusion limited to only those trials included one of the active drug interventions. We also excluded all studies not reported in English. Although the clinical review included data from 94 studies, the quality of data was generally low, particularly in terms of the reporting of standard deviation. There was also inconsistency between the results of the mixed-treatment comparison (MTC) and the pair-wise analyses.

CONCLUSION

The MTC of anti-obesity treatments shows that all the active treatments are effective at reducing weight and BMI. The economic results show that, compared with placebo, the treatments are all cost-effective when using a threshold of £20,000 per QALY, and, within the limitations of the data available, sibutramine 15 mg dominates the other three interventions. This work has highlighted many areas of methodological research that could be explored, including assessing inconsistencies within a network to determine differences between the results of pair-wise and MTC analyses; the use of meta-regression methods to look for effect modifiers; exploring the effect of local publication bias; and the use of joint models to analyse the repeated measures of BMI and the time-to-event processes simultaneously.

FUNDING

The National Institute for Health Research Health Technology Assessment programme.

A systematic review and mixed treatment comparison of pharmacological interventions for the treatment of obesity

The study aims to compare anti-obesity interventions in a single evidence synthesis framework. Electronic databases were searched for randomized controlled trials of orlistat, rimonabant or sibutramine reporting weight or body mass index (BMI) change from baseline at 3, 6 or 12 months. A mixed treatment comparison was used to combine direct and indirect trial evidence. Ninety-four studies involving 24,808 individuals were included; 83 trials included data on weight change and 41 on BMI change. All results are in comparison with placebo. The active drugs were all effective at reducing weight and BMI. At 3 months, orlistat reduced weight by -2.65 kg (95% credibility interval -4.00 kg, -1.31 kg). For sibutramine, 15 mg gave a greater reduction than 10 mg at 12 months, -6.35 kg versus -5.42 kg, respectively. Rimonabant reduced weight by -11.23 kg at 3 months and -4.55 kg at 12 months. Lifestyle advice alone also reduced weight at 6 and 12 months, but was less effective than the pharmacological interventions. In conclusion, modest weight reductions were seen for all pharmacological interventions. Those interventions which have now been withdrawn from use (sibutramine and rimonabant) seem to be the most effective, implying that there may be a place in clinical practice for similar drugs if side effects could be avoided.

Nicotine withdrawal exacerbates fear reactivity to CO₂-induced bodily sensations among smokers

INTRODUCTION

Independent lines of research suggest that smoking increases the prospective risk of panic disorder. Studies that have examined the hypothesized link between nicotine withdrawal and panic have typically employed light smokers or lacked optimal control groups. Our laboratory team previously found, for example, that smokers who abstained from cigarettes for 12 hr demonstrated greater fear reactivity to a CO(2) rebreathing challenge than nonsmokers. However, the absence of a smoking-as-usual group limited our ability to draw conclusions about the potential role of nicotine withdrawal.

METHODS

We exposed 27 heavy smokers who abstained from smoking for 12 hr and 27 heavy smokers who smoked as usual to a 5-min CO(2) rebreathing challenge.

RESULTS

More intense prechallenge nicotine withdrawal symptoms (regardless of group status) were associated with more severe panicky symptoms and a stronger urge to escape during the challenge, even after we controlled for prechallenge anxiety and daily cigarette use. Unexpectedly, group status did not predict challenge reactivity.

CONCLUSION

Smokers who regularly experience intense withdrawal symptoms, regardless of length of smoking abstinence, may be at heightened risk for experiencing panic attacks.

Sotrastaurin, a novel small molecule inhibiting protein-kinase C: randomized phase II study in renal transplant recipients

Sotrastaurin, a selective protein-kinase-C inhibitor, blocks early T-cell activation through a calcineurin-independent mechanism. In this study, de novo renal transplant recipients with immediate graft function were randomized 1:2 to tacrolimus (control, n = 44) or sotrastaurin (300 mg b.i.d.; n = 81). All patients received basiliximab, mycophenolic acid (MPA) and steroids. The primary endpoint was the composite of treated biopsy-proven acute rejection (BPAR), graft loss, death or lost to follow-up at month 3. The main safety assessment was estimated glomerular filtration rate (eGFR); modification of diet in renal disease (MDRD) at month 3. Composite efficacy failure at month 3 was higher for the sotrastaurin versus control regimen (25.7% vs. 4.5%, p = 0.001), driven by higher BPAR rates (23.6% vs. 4.5%, p = 0.003), which led to early study termination. Median (± standard deviation [SD]) eGFR was higher for sotrastaurin versus control at all timepoints from day 7 (month 3: 59.0 ± 22.3 vs. 49.5 ± 17.7 mL/min/1.73 m(2) , p = 0.006). The most common adverse events were gastrointestinal disorders (control: 63.6%; sotrastaurin: 88.9%) which led to study-medication discontinuation in two sotrastaurin patients. This study demonstrated a lower degree of efficacy but better renal function with the calcineurin-inhibitor-free regimen of sotrastaurin+MPA versus the tacrolimus-based control. Ongoing studies are evaluating alternative sotrastaurin regimens.

Etanercept, infliximab and adalimumab for the treatment of psoriatic arthritis: a systematic review and economic evaluation

BACKGROUND

Etanercept, infliximab and adalimumab are licensed in the UK for the treatment of active and progressive psoriatic arthritis (PsA) in adults who have an inadequate response to standard treatment.

OBJECTIVE

To determine the clinical effectiveness, safety and cost-effectiveness of these biologic agents in the treatment of active and progressive PsA.

DATA SOURCES

Systematic reviews were performed, with data sought from 10 electronic databases (MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, Science Citation Index, Conference Proceedings Citation Index - Science, ClinicalTrials.gov, metaRegister of Current Controlled Trials, NHS Economic Evaluation Database, Health Economic Evaluations Database and EconLit) up to June 2009.

REVIEW METHODS

Full paper manuscripts of titles/abstracts considered relevant were obtained and assessed for inclusion by two reviewers according to criteria on study design, interventions, participants and outcomes. Data on study and participant characteristics, efficacy outcomes, adverse effects, costs to the health service and cost-effectiveness were extracted, along with baseline data where reported. The primary efficacy outcomes were measures of anti-inflammatory response, skin lesion response and functional status, and the safety outcome was the incidence of serious adverse events. The primary measure of cost-effectiveness was incremental cost per additional quality-adjusted life-year (QALY). Standard meta-analytic techniques were applied to efficacy data. Published cost-effectiveness studies and the economic analyses submitted to the National Institute for Health and Clinical Excellence (NICE) by the biologic manufacturers were reviewed. An economic model was developed by updating the model produced by the York Assessment Group for the previous NICE appraisal of biologics in PsA.

RESULTS

Pooled estimates of effect demonstrated a significant improvement in patients with PsA for all joint disease and functional status outcomes at 12-14 weeks' follow-up. The biologic treatment significantly reduced joint symptoms for etanercept [relative risk (RR) 2.60, 95% confidence interval (CI) 1.96 to 3.45], infliximab (RR 3.44, 95% CI 2.53 to 4.69) and adalimumab (RR 2.24, 95% CI 1.74 to 2.88), with 24-week data demonstrating maintained treatment effects. Trial data demonstrated a significant effect of all three biologics on skin disease at 12 or 24 weeks. Evidence synthesis found that infliximab appeared to be most effective across all outcomes of joint and skin disease. The response in joint disease was greater with etanercept than with adalimumab, whereas the response in skin disease was greater with adalimumab than with etanercept, although these differences are not statistically significant. Under base-case assumptions, etanercept was the most likely cost-effective strategy for patients with PsA and mild-to-moderate psoriasis if the threshold for cost-effectiveness was £20,000 or £30,000 per QALY. All biologics had a similar probability of being cost-effective for patients with PsA and moderate-to-severe psoriasis at a threshold of £20,000 per QALY.

LIMITATIONS

Limited available efficacy data and difficulty in assessing PsA activity and its response to biologic therapy.

CONCLUSIONS

The data indicated that etanercept, infliximab and adalimumab were efficacious in the treatment of PsA compared with placebo, with beneficial effects on joint symptoms, functional status and skin. Short-term data suggested that these biologic agents can delay joint disease progression and evidence to support their use in the treatment of PsA is convincing. Future research would benefit from long-term observational studies with large sample sizes of patients with PsA to demonstrate that beneficial effects are maintained, along with further monitoring of the safety profiles of the biologic agents.

FUNDING

The National Institute for Health Research Health Technology Assessment programme.

Panic-Relevant Cognitive Processes Among Smokers

To further understand the frequent co-occurrence of smoking and panic disorder (PD), we examined panic-relevant cognitive processes among heavy smokers, half of whom were in 12-hour withdrawal, and nonsmokers. All participants (N = 85) underwent a 5-minute carbon dioxide rebreathing challenge. Prior to the challenge, participants completed questionnaires on reasons for smoking, anxiety sensitivity, and suffocation fear. Results are consistent with a model in which smokers with predisposing risk factors (high anxiety sensitivity and high suffocation fear) misappraise bodily sensations and experience panicky symptoms. No evidence was found that being in acute withdrawal heightened this risk. Overall, findings highlight (a) cognitive vulnerabilities that may place smokers at elevated risk for developing PD and hence (b) potential targets for intervention.

Personality, gender, and family history in the prediction of college gambling

The present study examined the degree to which gambling behaviors and gambling-relevant cognitive distortions could be predicted by personality factors, gender, and familial history of substance use and gambling problems in a large sample of college students (N = 581). Results indicate that parental gambling problems and, especially for males, a propensity to experience negative emotions predicted time spent gambling and gambling problems. Negative emotionality, along with parental substance use problems, impulsivity, and being male predicted gambling-related cognitive distortions. The differing pattern for impulsivity with respect to behaviors and beliefs might be explained by the low accessibility of gambling venues for the student population. We compare the present findings with past studies examining gambling behaviors in adult populations.