Psychotropic Medication Use among Medicare Beneficiaries Following Traumatic Brain Injury

Objectives—To characterize psychotropic medication use before and after traumatic brain injury (TBI) hospitalization among older adults. A secondary objective is to determine how receipt of indicated pharmacologic treatment for anxiety and post-traumatic stress disorder (PTSD) differs following TBI. Design—Retrospective cohort Setting—United States Participants—Medicare beneficiaries age ≥65 hospitalized with TBI 2006-2010 with continuous drug coverage for 12 months before and after TBI (n=60,276). Measurements—We obtained monthly psychotropic medication use by drug class and specific drugs from Medicare Part D drug event files. International Classification of Disease, 9th Edition CM, codes were used to define anxiety (300.0x) and PTSD (309.81). Results—Average monthly prevalence of psychotropic medication use among all patients hospitalized for TBI was 44.8%; antidepressants comprised 73%. Prevalence of psychotropic medication use increased from 2006-2010. Following TBI, psychotropic medication use increased slightly (odds ratio (OR) 1.05; 95% confidence interval (CI) 1.03, 1.06.) Tricyclic antidepressant use decreased post-TBI (OR 0.76; 95% CI 0.73, 0.79) while use of the sedating antidepressants mirtazapine (OR 1.31; 95% CI 1.25, 1.37) and trazadone (OR 1.11; 95% CI 1.06, 1.17) increased. Antipsychotic (OR 1.15; 95% CI 1.12, 1.19) use also increased post-TBI. Beneficiaries newly diagnosed with anxiety (OR 0.42; 95% CI 0.36, 0.48) and/or PTSD (OR 0.39; 95% CI 0.18, 0.84) post-TBI were less likely to receive indicated pharmacologic treatment. Conclusions—Older adults hospitalized with TBI have a high prevalence of psychotropic medication use yet are less likely to receive indicated pharmacological treatment for newly diagnosed anxiety and PTSD following TBI

Monetary discounting and ventral striatal dopamine receptor availability in nontreatment-seeking alcoholics and social drinkers

RATIONALE: Dopamine (DA) in the ventral striatum (VST) has long been implicated in addiction pathologies, yet its role in temporal decision-making is not well-understood. OBJECTIVES: To determine if VST DA D2 receptor availability corresponds with greater impulsive choice in both nontreatment-seeking alcoholics (NTS) and social drinkers (SD). METHODS: NTS subjects (n = 10) and SD (n = 13) received PET scans at baseline with the D2/D3 radioligand [(11)C]raclopride (RAC). Outside the scanner, subjects performed a delay discounting procedure with monetary rewards. RAC binding potential (BPND) was estimated voxelwise, and correlations were performed to test for relationships between VST BPND and delay discounting performance. Self-reported impulsivity was also tested for correlations with BPND. RESULTS: Across all subjects, greater impulsive choice for $20 correlated with lower BPND in the right VST. NTS showed greater impulsive choice than SD and were more impulsive by self-report. Across all subjects, the capacity of larger rewards to reduce impulsive choice (the magnitude effect) correlated negatively (p = 0.028) with problematic alcohol use (AUDIT) scores. Self-reported impulsivity did not correlate with BPND in VST. CONCLUSIONS: Preference for immediate reinforcement may reflect greater endogenous striatal DA or lower D2 number, or both. Alcoholic status did not mediate significant effects on VST BPND, suggesting minimal effects from alcohol exposure. The apparent lack of BPND correlation with self-reported impulsivity highlights the need for objective behavioral assays in the study of the neurochemical substrates of behavior. Finally, our results suggest that the magnitude effect may be more sensitive to alcohol-induced problems than single discounting measures

Differential dopamine function in fibromyalgia

Approximately 30% of Americans suffer from chronic pain disorders, such as fibromyalgia (FM), which can cause debilitating pain. Many pain-killing drugs prescribed for chronic pain disorders are highly addictive, have limited clinical efficacy, and do not treat the cognitive symptoms reported by many patients. The neurobiological substrates of chronic pain are largely unknown, but evidence points to altered dopaminergic transmission in aberrant pain perception. We sought to characterize the dopamine (DA) system in individuals with FM. Positron emission tomography (PET) with [18F]fallypride (FAL) was used to assess changes in DA during a working memory challenge relative to a baseline task, and to test for associations between baseline D2/D3 availability and experimental pain measures. Twelve female subjects with FM and eleven female controls completed study procedures. Subjects received one FAL PET scan while performing a “2-back” task, and one while performing a “0-back” (attentional control, “baseline”) task. FM subjects had lower baseline FAL binding potential (BP) in several cortical regions relative to controls, including anterior cingulate cortex. In FM subjects, self-reported spontaneous pain negatively correlated with FAL BP in the left orbitofrontal cortex and parahippocampal gyrus. Baseline BP was significantly negatively correlated with experimental pain sensitivity and tolerance in both FM and CON subjects, although spatial patterns of these associations differed between groups. The data suggest that abnormal DA function may be associated with differential processing of pain perception in FM. Further studies are needed to explore the functional significance of DA in nociception and cognitive processing in chronic pain

B0 -> D*- a1+: Chirality tests and resolving an ambiguity in 2\beta+\gamma

We point out that the decays of B mesons into a vector meson and an axial-vector meson can distinguish between left and right-handed polarized mesons, in contrast to decays into two vector mesons. Measurements in B0 -> D*-a1+ are proposed for testing factorization and the V-A structure of the weak b -> c current, and for resolving a discrete ambiguity in 2\beta + \gamma.Comment: 4 page

Measuring dark energy spatial inhomogeneity with supernova data

The gravitational lensing distortion of distant sources by the large-scale distribution of matter in the Universe has been extensively studied. In contrast, very little is known about the effects due to the large-scale distribution of dark energy. We discuss the use of Type Ia supernovae as probes of the spatial inhomogeneity and anisotropy of dark energy. We show that a shallow, almost all-sky survey can limit rms dark energy fluctuations at the horizon scale down to a fractional energy density of ~10^-4Comment: 4 pages; PRL submitte

Reliability of Striatal [11C]Raclopride Binding in Smokers Wearing Transdermal Nicotine Patches

PURPOSE: In studies where [(11)C]raclopride (RAC) positron emission tomography (PET) is used to assess changes in striatal dopamine, it is important to control for cognitive states, such as drug craving, that could alter dopamine levels. In cigarette smokers, transdermal nicotine patches (TNP) can control nicotine craving, but the effects of nicotine patches on RAC binding are unknown. Thus, we sought to determine the test-retest reliability of RAC binding in the presence of nicotine patches. METHODS: Eleven male smokers were scanned twice with RAC on separate days while wearing TNP. RESULTS: Across the striatum, test-retest variability was 7.63 ± 5.88; percent change in binding potential was 1.11 ± 9.83; and the intraclass correlation coefficient was 0.91 (p < 0.0001). CONCLUSION: Baseline RAC binding is highly reproducible in smokers wearing nicotine patches. This suggests that TNP are an acceptable method for controlling cigarette craving during studies that utilize RAC to examine changes in dopamine