Twenty-four hours after administration, ketamine exerts rapid and robust antidepressant effects that are thought to be mediated by activation of the mechanistic target of rapamycin complex 1 ...(mTORC1). To test this hypothesis, depressed patients were pretreated with rapamycin, an mTORC1 inhibitor, prior to receiving ketamine. Twenty patients suffering a major depressive episode were randomized to pretreatment with oral rapamycin (6 mg) or placebo 2 h prior to the intravenous administration of ketamine 0.5 mg/kg in a double-blind cross-over design with treatment days separated by at least 2 weeks. Depression severity was assessed using Montgomery-Åsberg Depression Rating Scale (MADRS). Rapamycin pretreatment did not alter the antidepressant effects of ketamine at the 24-h timepoint. Over the subsequent 2-weeks, we found a significant treatment by time interaction (F
= 2.02, p = 0.04), suggesting a prolongation of the antidepressant effects of ketamine by rapamycin. Two weeks following ketamine administration, we found higher response (41%) and remission rates (29%) following rapamycin + ketamine compared to placebo + ketamine (13%, p = 0.04, and 7%, p = 0.003, respectively). In summary, single dose rapamycin pretreatment failed to block the antidepressant effects of ketamine, but it prolonged ketamine's antidepressant effects. This observation raises questions about the role of systemic vs. local blockade of mTORC1 in the antidepressant effects of ketamine, provides preliminary evidence that rapamycin may extend the benefits of ketamine, and thereby potentially sheds light on mechanisms that contribute to depression relapse after ketamine administration.
Alcohol and marijuana are the two most abused substances in US colleges. However, research on the combined influence (cross sectional or longitudinal) of these substances on academic performance is ...currently scant.
Data were derived from the longitudinal 2-year Brain and Alcohol Research in College Students (BARCS) study including 1142 freshman students who completed monthly marijuana use and alcohol consumption surveys. Subjects were classified into data-driven groups based on their alcohol and marijuana consumption. A linear mixed-model (LMM) was employed using this grouping factor to predict grade point average (GPA), adjusted for a variety of socio-demographic and clinical factors.
Three data-driven clusters emerged: 1) No/low users of both, 2) medium-high alcohol/no-low marijuana, and 3) medium-high users of both substances. Individual cluster derivations between consecutive semesters remained stable. No significant interaction between clusters and semester (time) was noted. Post-hoc analysis suggest that at the outset, compared to sober peers, students using moderate to high levels of alcohol and low marijuana demonstrate lower GPAs, but this difference becomes non-significant over time. In contrast, students consuming both substances at moderate-to-high levels score significantly lower at both the outset and across the 2-year investigation period. Our follow-up analysis also indicate that when students curtailed their substance use over time they had significantly higher academic GPA compared to those who remained stable in their substance use patterns over the two year period.
Overall, our study validates and extends the current literature by providing important implications of concurrent alcohol and marijuana use on academic achievement in college.
Antidepressant treatment efficacy is low, but might be improved by matching patients to interventions. At present, clinicians have no empirically validated mechanisms to assess whether a patient with ...depression will respond to a specific antidepressant. We aimed to develop an algorithm to assess whether patients will achieve symptomatic remission from a 12-week course of citalopram.
We used patient-reported data from patients with depression (n=4041, with 1949 completers) from level 1 of the Sequenced Treatment Alternatives to Relieve Depression (STAR*D; ClinicalTrials.gov, number NCT00021528) to identify variables that were most predictive of treatment outcome, and used these variables to train a machine-learning model to predict clinical remission. We externally validated the model in the escitalopram treatment group (n=151) of an independent clinical trial (Combining Medications to Enhance Depression Outcomes COMED; ClinicalTrials.gov, number NCT00590863).
We identified 25 variables that were most predictive of treatment outcome from 164 patient-reportable variables, and used these to train the model. The model was internally cross-validated, and predicted outcomes in the STAR*D cohort with accuracy significantly above chance (64·6% SD 3·2; p<0·0001). The model was externally validated in the escitalopram treatment group (N=151) of COMED (accuracy 59·6%, p=0.043). The model also performed significantly above chance in a combined escitalopram-buproprion treatment group in COMED (n=134; accuracy 59·7%, p=0·023), but not in a combined venlafaxine-mirtazapine group (n=140; accuracy 51·4%, p=0·53), suggesting specificity of the model to underlying mechanisms.
Building statistical models by mining existing clinical trial data can enable prospective identification of patients who are likely to respond to a specific antidepressant.
Yale University.
Exercise is known to be associated with reduced risk of all-cause mortality, cardiovascular disease, stroke, and diabetes, but its association with mental health remains unclear. We aimed to examine ...the association between exercise and mental health burden in a large sample, and to better understand the influence of exercise type, frequency, duration, and intensity.
In this cross-sectional study, we analysed data from 1 237 194 people aged 18 years or older in the USA from the 2011, 2013, and 2015 Centers for Disease Control and Prevention Behavioral Risk Factors Surveillance System survey. We compared the number of days of bad self-reported mental health between individuals who exercised and those who did not, using an exact non-parametric matching procedure to balance the two groups in terms of age, race, gender, marital status, income, education level, body-mass index category, self-reported physical health, and previous diagnosis of depression. We examined the effects of exercise type, duration, frequency, and intensity using regression methods adjusted for potential confounders, and did multiple sensitivity analyses.
Individuals who exercised had 1·49 (43·2%) fewer days of poor mental health in the past month than individuals who did not exercise but were otherwise matched for several physical and sociodemographic characteristics (W=7·42 × 10
, p<2·2 × 10
). All exercise types were associated with a lower mental health burden (minimum reduction of 11·8% and maximum reduction of 22·3%) than not exercising (p<2·2 × 10
for all exercise types). The largest associations were seen for popular team sports (22·3% lower), cycling (21·6% lower), and aerobic and gym activities (20·1% lower), as well as durations of 45 min and frequencies of three to five times per week.
In a large US sample, physical exercise was significantly and meaningfully associated with self-reported mental health burden in the past month. More exercise was not always better. Differences as a function of exercise were large relative to other demographic variables such as education and income. Specific types, durations, and frequencies of exercise might be more effective clinical targets than others for reducing mental health burden, and merit interventional study.
Cloud computing resources were provided by Microsoft.
Rationale
The nicotine delivery rate is a key feature of tobacco product design, yet there have been limited human studies examining the effects of nicotine as a function of delivery rate.
Objective
...We developed an intravenous nicotine infusion protocol to evaluate differential effects of nicotine delivery rate on subjective drug effects, smoking urges, abstinence symptoms, heart rate, and blood pressure.
Methods
Eighteen non-treatment seeking, overnight abstinent male and female smokers (18 to 30 years old), who smoked ≥ 5 cigarettes per day for the past year completed four sessions, in which they were randomly assigned to a saline infusion, or a 1 mg per 70-kg body weight dose of nicotine delivered over 1, 5, or 10 min at rates of 0.24, 0.048, or 0.024 μg/kg/s, respectively.
Results
Smoking urges, as assessed by the Brief Questionnaire of Smoking Urges, were reduced relative to placebo for the 1- and 5-min infusion, but not the 10-min infusion. Although the 1- and 5-min infusions reduced smoking urges to a similar extent, the 1-min infusion induced a greater heart rate and blood pressure increase. Changes to subjective drug effects, heart rate, and blood pressure delineate the differential effects of nicotine delivery rate for these outcomes.
Conclusions
We have characterized the delivery rate-response curve for a nicotine dose that is roughly the amount of nicotine (~ 1 mg) delivered by smoking a standard tobacco cigarette. Our findings reinforce the importance of nicotine delivery rate when evaluating the potential effects of nicotine from tobacco products.
Abstract Somatic DNA methyl transferase 3A ( DNMT3A ) mutations have been recognized recently as recurrent molecular aberrations in acute myeloid leukemia (AML). The precise role of these mutations ...in leukemogenesis remains elusive but a number of studies have already been conducted to study their potential prognostic value in AML patients with variable results. We performed a meta-analysis on published data from over 4500 AML patients to provide robust evidence supporting DNMT3A mutation testing in clinical setting for AML patients. Our meta-analysis showed that DNMT3A mutations were associated with M4 and M5 AML subtypes. Those mutations conferred significantly worse prognosis with both shorter OS ( p = 0.0004) and shorter RFS ( p = 0.002). Notably, DNMT3A mutations appeared to be an independent adverse prognostic factor also in younger patients with normal cytogenetics AML (OS ( p = 0.01) and RFS ( p = 0.0005)) and also in the subgroup of patients with high risk genotypes defined according to the criteria of the European Leukemia Net (ELN) (OS ( p = 0.002)). Therefore, DNMT3A mutational status can improve the risk stratification of AML patients in the setting of integrated mutational profiling.
Our group has established the feasibility of using on-body electrocardiographic (ECG) sensors to detect cocaine use in the human laboratory. The purpose of the current study was to test whether ECG ...sensors and features are capable of discriminating cocaine use from other non-cocaine sympathomimetics.
Eleven subjects with cocaine use disorder wore the Zephyr BioHarness™ 3 chest band under six experimental (drug and non-drug) conditions, including 1) laboratory, intravenous cocaine self-administration, 2) after a single oral dose of methylphenidate, 3) during aerobic exercise, 4) during tobacco use (N=7 who smoked tobacco), and 5) during routine activities of daily inpatient living (unit activity). Three ECG-derived feature sets served as primary outcome measures, including 1) the RR interval (i.e., heart rate), 2) a group of ECG interval proxies (i.e., PR, QS, QT and QTc intervals), and 3) the full ECG waveform. Discriminatory power between cocaine and non-cocaine conditions for each of the three outcomes measures was expressed as the area under the receiver operating characteristics (AUROC) curve.
All three outcomes successfully discriminated cocaine use from unit activity, exercise, tobacco, and methylphenidate conditions with a mean AUROC values ranging from 0.66 to 0.99 and with least squares means values all statistically different/higher than 0.5 among all subjects F(3, 99) = 3.38, p =0.02 and among those with tobacco use F(4, 84) = 5.39, p = 0.0007.
These preliminary results support discriminatory power of wearable ECG sensors for detecting cocaine use.
•Electrocardiographic (ECG) changes occur with cocaine use.•On-body ECG sensors can discriminate cocaine use from non-cocaine conditions.•ECG-derived features exhibit varying degrees of specificity.•Cocaine may exhibit ECG signatures unique from those of other sympathomimetics.•Remote wireless sensors are promising mHealth tools for cocaine use detection.
The goal of this study was to infer the effectiveness of midazolam as a comparator in preserving the blind in ketamine studies for mood disorders through patient-level analyses of efficacy trial ...outcomes. In this integrative data analysis (k = 9, N = 367 patients with mood disorders), clinical outcomes were compared across four groups: ketamine (midazolam-controlled), ketamine (saline-controlled), midazolam, and saline. Ketamine doses ranged from 0.5 to 0.54 mg/kg and midazolam doses ranged from 0.02 to 0.045 mg/kg. The baseline-to-Day 1 effect size was d = 0.7 (95% CI: 0.4-0.9) for ketamine (midazolam) versus midazolam and d = 1.8 (95% CI: 1.4-2.2) for ketamine (saline) versus saline. The effect of ketamine relative to control was larger in saline-controlled studies than in midazolam-controlled studies (t(276) = 2.32, p = 0.02). This was driven by a comparatively larger effect under midazolam than saline (t(111) = 5.40, p < 0.0001), whereas there was no difference between ketamine (midazolam) versus ketamine (saline) (t(177) = 0.65, p = 0.51). Model-estimated rates of response (with 95% CI) yielded similar results: ketamine (midazolam), 45% (34-56%); ketamine (saline), 46% (34-58%); midazolam, 18% (6-30%); saline, 1% (0-11%). The response rate for ketamine was higher than the control condition for both saline (t(353) = 7.41, p < 0.0001) and midazolam (t(353) = 4.59, p < 0.0001). Studies that used midazolam as a comparator yielded smaller effects of ketamine than those which used saline, which was accounted for by greater improvement following midazolam compared to saline.
Rationale
Reducing nicotine content of inhaled tobacco products may prevent nicotine addiction, but the threshold for nicotine reinforcement has not been systematically evaluated in controlled human ...laboratory studies.
Objectives
The current study uses a novel double-blind placebo-controlled intravenous (IV) nicotine self-administration (NSA) model to determine threshold for subjective effects of nicotine and nicotine reinforcement using a forced choice self-administration procedure.
Methods
Young adults (
n
= 34) had 5 laboratory sessions after overnight nicotine abstinence. In each session, participants sampled and rated the subjective effects of an IV dose of nicotine (0.0125, 0.025, 0.05, 0.1, or 0.2 mg nicotine/70 kg bodyweight) versus saline (placebo), then were given a total of 10 opportunities to self-administer either the IV dose of nicotine or placebo.
Results
Mixed effect models revealed a significant effect of nicotine dose for positive (i.e., “stimulatory” and “pleasurable”;
p
< .0001) effects, but not “aversive” effects during sampling period. Post hoc comparisons showed that higher doses (i.e., 0.1 and 0.2 mg) were associated with greater stimulatory, pleasurable, and physiological effects than placebo and lower doses. Mixed effect models revealed that only the highest dose (i.e., 0.2 mg) was consistently preferred over placebo. Sex differences were generally weak (
p
= .03–.05).
Conclusions
Using our IV nicotine NSA model, the threshold for detecting positive effects of nicotine in young adult smokers is about 0.1 mg, but a higher dose of nicotine, 0.2 mg, is required to produce a consistent nicotine reinforcement. Regarding the regulatory impact, our findings further support the value of nicotine reinforcement threshold as a tobacco regulatory target.
Smartbands can be used to detect cigarette smoking and deliver real time smoking interventions. Brief mindfulness interventions have been found to reduce smoking.
This single arm feasibility trial ...used a smartband to detect smoking and deliver brief mindfulness exercises.
Daily smokers who were motivated to reduce their smoking wore a smartband for 60 days. For 21 days, the smartband monitored, detected and notified the user of smoking in real time. After 21 days, a 'mindful smoking' exercise was triggered by detected smoking. After 28 days, a 'RAIN' (recognize, allow, investigate, nonidentify) exercise was delivered to predicted smoking. Participants received mindfulness exercises by text message and online mindfulness training. Feasibility measures included treatment fidelity, adherence and acceptability.
Participants (N=155) were 54% female, 76% white non-Hispanic, and treatment starters (n=115) were analyzed. Treatment fidelity cutoffs were met, including for detecting smoking and delivering mindfulness exercises. Adherence was mixed, including moderate smartband use and low completion of mindfulness exercises. Acceptability was mixed, including high helpfulness ratings and mixed user experiences data. Retention of treatment starters was high (81.9%).
Findings demonstrate the feasibility of using a smartband to track smoking and deliver quit smoking interventions contingent on smoking.
PDF
