223 research outputs found

    Dissection of Hypothalamic-Pituitary-Adrenal Axis Pathology in 1-Month-Abstinent Alcohol-Dependent Men, Part 2: Response to Ovine Corticotropin-Releasing Factor and Naloxone

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    Pituitary and adrenal responsiveness is suppressed in abstinent alcohol-dependent individuals. To clarify the specific organizational disruption in hypothalamic-pituitary-adrenal functioning during early abstinence, the authors separately assessed each level of the stress-response axis. In this second of a two-part study, ovine corticotropin-releasing factor (oCRH) was used to stimulate the pituitary corticotrophs, and naloxone was used to activate the axis at the hypothalamic level. In addition, pulsatile characteristics of corticotropin and cortisol were assessed over a 12-hr period (0800 to 2000 hr). Methods : Eleven abstinent alcohol-dependent men and 10 healthy comparison participants were assessed. All participants were between the ages of 30 and 50 years, and alcohol-dependent patients were abstinent from 4 to 6 weeks. Basal concentrations of corticotropin and cortisol were obtained every 10 min from 0800 to 2000 hr and subjected to pulsatile analysis. Plasma corticotropin and cortisol concentrations were then obtained every 5 to 10 min after low-dose, intravenously administered doses of oCRH (0.4 μg/kg) or naloxone (0.125 mg/kg). Medications were administered at 2000 hr and the two challenge studies were separated by 48 hr. Results : Pulsatile analysis revealed that the mean corticotropin amplitude was increased in alcohol-dependent patients relative to controls ( p < 0.05). Other pulsatile characteristics of corticotropin and all cortisol pulsatile measures were not significantly different between the two groups. The integrated cortisol response to oCRH was significantly lower in alcohol-dependent patients compared with controls ( p < 0.01), but the integrated corticotropin response was not significantly different. In contrast, neither the corticotropin nor the cortisol response to naloxone was significantly different between groups. Conclusions : Adrenocorticoid hyposensitivity persists after oCRH infusion for at least 1 month after cessation of drinking, whereas hyporesponsiveness of the pituitary corticotrophs to CRH seems to resolve with continued abstinence. The authors suggest that adrenocortical hyporesponsiveness during prolonged abstinence may impact relapse risk.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/65174/1/01.ALC.0000158939.25531.EE.pd

    Relapse to smoking during unaided cessation: Clinical, cognitive, and motivational predictors

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    Rationale: Neurobiological models of addiction suggest that abnormalities of brain reward circuitry distort salience attribution and inhibitory control processes, which in turn contribute to high relapse rates. Objectives: To determine whether impairments of salience attribution and inhibitory control predict relapse in a pharmacologically unaided attempt at smoking cessation. Methods: 141 smokers were assessed on indices of nicotine consumption / dependence (e.g. the FTND, cigarettes per day, salivary cotinine), and three trait impulsivity measures. After overnight abstinence they completed experimental tests of cue reactivity, attentional bias to smoking cues, response to financial reward, motor impulsiveness, and response inhibition (antisaccades). They then started a quit attempt with follow-up after 7 days, 1 month, and 3 months; abstinence was verified via salivary cotinine levels ≤ 20ng/ml. Results: Relapse rates at each point were 52.5%, 64% and 76.3%. The strongest predictor was pre-cessation salivary cotinine; other smoking / dependence indices did not explain additional outcome variance and neither did trait impulsivity. All experimental indices except responsivity to financial reward significantly predicted one week outcome. Salivary cotinine, attentional bias to smoking cues and antisaccade errors explained unique as well as shared variance. At one and three months, salivary cotinine, motor impulsiveness and cue reactivity were all individually predictive; the effects of salivary cotinine and motor impulsiveness were additive. Conclusions: These data provide some support for the involvement of abnormal cognitive and motivational processes in sustaining smoking dependence and suggest that they might be a focus of interventions, especially in the early stages of cessation. Dawkins L, Powell JH, Pickering AD, Powell JF, and West RJ (2009) Addiction 104, 850-

    The lancet weight determines wheal diameter in response to skin prick testing with histamine

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    BACKGROUND:Skin prick test (SPT) is a common test for diagnosing immunoglobulin E-mediated allergies. In clinical routine, technicalities, human errors or patient-related biases, occasionally results in suboptimal diagnosis of sensitization. OBJECTIVE:Although not previously assessed qualitatively, lancet weight is hypothesized to be important when performing SPT to minimize the frequency of false positives, false negatives, and unwanted discomfort. METHODS:Accurate weight-controlled SPT was performed on the volar forearms and backs of 20 healthy subjects. Four predetermined lancet weights were applied (25 g, 85 g, 135 g and 265 g) using two positive control histamine solutions (1 mg/mL and 10 mg/mL) and one negative control (saline). A total of 400 SPTs were conducted. The outcome parameters were: wheal size, neurogenic inflammation (measured by superficial blood perfusion), frequency of bleeding, and the lancet provoked pain response. RESULTS:The mean wheal diameter increased significantly as higher weights were applied to the SPT lancet, e.g. from 3.2 ± 0.28 mm at 25 g to 5.4 ± 1.7 mm at 265 g (p<0.01). Similarly, the frequency of bleeding, the provoked pain, and the neurogenic inflammatory response increased significantly. At 265 g saline evoked two wheal responses (/160 pricks) below 3 mm. CONCLUSION AND CLINICAL RELEVANCE:The applied weight of the lancet during the SPT-procedure is an important factor. Higher lancet weights precipitate significantly larger wheal reactions with potential diagnostic implications. This warrants additional research of the optimal lancet weight in relation to SPT-guidelines to improve the specificity and sensitivity of the procedure

    There is no age limit for methadone: a retrospective cohort study

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    BACKGROUND: Data from the US indicates that methadone-maintained populations are aging, with an increase of patients aged 50 or older. Data from European methadone populations is sparse. This retrospective cohort study sought to evaluate the age trends and related developments in the methadone population of Basel-City, Switzerland. METHODS: The study included methadone patients between April 1, 1995 and March 31, 2003. Anonymized data was taken from the methadone register of Basel-City. For analysis of age distributions, patient samples were split into four age categories from '20-29 years' to '50 years and over'. Cross-sectional comparisons were performed using patient samples of 1996 and 2003. RESULTS: Analysis showed a significant increase in older patients between 1996 and 2003 (p < 0.001). During that period, the percentage of patients aged 50 and over rose almost tenfold, while the proportion of patients aged under 30 dropped significantly from 52.8% to 12.3%. The average methadone dose (p < 0.001) and the 1-year retention rate (p < 0.001) also increased significantly. CONCLUSIONS: Findings point to clear trends in aging of methadone patients in Basel-City which are comparable, although less pronounced, to developments among US methadone populations. Many unanswered questions on medical, psychosocial and health economic consequences remain as the needs of older patients have not yet been evaluated extensively. However, older methadone patients, just as any other patients, should be accorded treatment appropriate to their medical condition and needs. Particular attention should be paid to adequate solutions for persons in need of care
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