Acute neurocognitive and subjective effects of oral methamphetamine with low doses of alcohol: A randomised controlled trial

BACKGROUND

Methamphetamine is often recreationally co-consumed with alcohol due to desirable off-target effects; however, the acute neurocognitive and subjective consequences of combined use are unclear.

METHODS

In a randomised, placebo-controlled, counterbalanced, cross-over study design, the effects of acute oral methamphetamine (0.42 mg/kg) were assessed with and without low doses of alcohol (target 0.04% blood-alcohol concentration, BAC) on subjective intoxication, alertness, physiological outcomes and neurocognition during the ascending and descending phases of the BAC curve. Sixteen healthy adults (mean age = 30.4 years, SD ± 4.4, 67% male) completed four experimental sessions over 4 weeks involving a one-week washout period.

RESULTS

Cardiovascular measures [heart rate (beats/minute), blood pressure (mmHg)] were predictably elevated following methamphetamine, but unaffected by combined alcohol use. Methamphetamine and alcohol produce divergent effects on subjective alertness and sedation across time, yet their combination produced predominantly sustained stimulative effects independent of the biphasic alcohol curve. At a peak BAC of 0.029%, alcohol alone impaired performance across most functional neurocognitive domains relative to placebo and methamphetamine only, and the addition of methamphetamine attenuated these effects. Methamphetamine alone produced isolated improvement in psychomotor speed consistent with peak drug effects.

CONCLUSION

Methamphetamine combined with alcohol does not substantially alter the physiological or metabolic profile compared to either drug alone. Strong stimulative effects of methamphetamine appear to mask the biphasic sedative and performance effects of low doses of alcohol, which may underlie motivations for co-consumption in recreational settings and increase propensity for harm.

Effect of CannEpil® on simulated driving performance and co-monitoring of ocular activity: A randomised controlled trial

BACKGROUND

Medicinal cannabis products containing Δ9-tetrahydrocannabinol (THC) are increasingly accessible. Yet, policy guidelines regarding fitness to drive are lacking, and cannabinoid-specific indexations of impairment are underdeveloped.

AIMS

To determine the impact of a standardised 1 mL sublingual dose of CannEpil^®, a medicinal cannabis oil containing 100 mg cannabidiol (CBD) and 5 mg THC on simulated driving performance, relative to placebo and whether variations in vehicle control can be indexed by ocular activity.

METHODS

A double-blind, within-subjects, randomised, placebo-controlled, crossover trial assessed 31 healthy fully licensed drivers (15 male, 16 female) aged between 21 and 58 years (M = 38.0, SD = 10.78). Standard deviation of lateral position (SDLP), standard deviation of speed (SDS) and steering variability were assessed over time and as a function of treatment during a 40 min simulated drive, with oculomotor parameters assessed simultaneously. Oral fluid and plasma were collected at 30 min and 2.5 h.

RESULTS

CannEpil did not significantly alter SDLP across the full drive, although increased SDLP was observed between 20 and 30 min (p < 0.05). CannEpil increased SDS across the full drive (p < 0.05), with variance greatest at 20-30 min (p < 0.001). CannEpil increased fixation duration (p < 0.05), blink rate (trend p = 0.051) and decreased blink duration (p < 0.001) during driving. No significant correlations were observed between biological matrices and performance outcomes.

CONCLUSIONS

CannEpil impairs select aspects of vehicle control (speed and weaving) over time. Alterations to ocular behaviour suggest that eye tracking may assist in determining cannabis-related driver impairment or intoxication. Australian and New Zealand Clinician Trials Registry, https://anzctr.org.au(ACTRN12619000932167).

Effects of alcohol intoxication on driving performance, confidence in driving ability, and psychomotor function: a randomized, double-blind, placebo-controlled study

RATIONALE

Alcohol-induced driving impairment can occur with any departure from a zero-blood alcohol concentration (BAC). Because intoxication is characterised by impaired judgement, drivers under the influence of alcohol may overestimate their capacity to safely operate a vehicle.

OBJECTIVES

This study examined the effects of alcohol on driving performance, four-choice reaction time (FCRT), and self-rated confidence in driving ability. It specifically focused on alcohol doses equal to commonly enforced legal BAC limits (i.e. 0.05% and 0.08%).

METHODS

A randomized, double-blind, placebo-controlled design was utilised. Seventeen participants were tested in three conditions: placebo and two alcohol conditions aiming for BACs of 0.05% and 0.08%. Participants underwent a baseline FCRT task and a 1-h simulated highway driving task before completing another FCRT task and rated their confidence in their driving ability.

RESULTS

The high and low alcohol dose conditions resulted in a mean BAC of 0.07%, and 0.04%, respectively (n = 17). The high BAC treatment significantly increased standard deviation of lateral position (SDLP) by 4.06 ± 5.21 cm and standard deviation of speed (SDS) by 0.69 ± 0.17 km/h relative to placebo, while confidence in driving ability remained unchanged across treatments. FCRT performance was impaired by the high BAC treatment (all < 0.01), but there we no significant differences between placebo and low BAC conditions.

CONCLUSIONS

The findings of this study show that driving performance and associated psychomotor functioning become significantly impaired below legally permissible driving limits in some jurisdictions. We identified a dissociation between driving performance and subjective awareness of impairment. Despite a significantly diminished driving ability at 0.07% BAC, drivers were unaware of their impairment.

The Combined Effects of Alcohol and Benzodiazepines on Driving-Related Neurocognitive Skills: A Systematic Review

OBJECTIVE

Research concerning the combined effects of alcohol and benzodiazepines on driving-related skills is largely inconsistent. Because as many as 88% of benzodiazepine users report the additional consumption of alcohol, this review aims to provide an updated and concise synthesis of the available high-quality research.

METHOD

We searched EBSCOhost, PubMed, Scopus, and Web of Science until April 1, 2020, for double-blind, placebo-controlled, repeated-measures intervention trials that examined the effects of alcohol (any dose provided as blood alcohol concentration [BAC]) in combination with oral benzodiazepines on neurocognitive tasks related to driving.

RESULTS

We identified evidence of a substance and timing-dependent interaction for measures of reaction time, tracking, divided attention, and visual functioning. Administering alcohol in conjunction with or shortly after a benzodiazepine resulted in a stronger interactive effect than when administration occurred further apart. An additive and/or synergistic effect often occurred when a therapeutic dose of benzodiazepine was combined with alcohol at a BAC below .05%.

CONCLUSIONS

Combined alcohol and benzodiazepine use was associated with significant impairments in driving-related neurocognitive skills. There is a clear need for more high-quality research in this area to better elucidate the mechanisms of alcohol and benzodiazepine interactions. Drivers may be unaware of impairments following the combination of these drugs at legal driving limits. Thus, drivers should be warned to take caution when consuming even small amounts of alcohol while under treatment with benzodiazepines.

Driver monitoring systems (DMS): The future of impaired driving management?

OBJECTIVE

Driver monitoring systems (DMS) are the next generation of vehicle safety technology. Broadly, these refer to the embedded, aftermarket wearable or vehicle-mounted devices that collect observable information about the operator to make real-time assessment of their capacity to perform the driving task. Integrating biobehavioral monitoring (primarily ocular metrics) with driving performance assessments, these systems function to infer driver state in real time to identify operator conditions that negatively affect driving (such as fatigue, inattention, or distraction).

METHOD

We review available methods used to infer driver state, as referenced against accepted models for optimal performance. Modeling our observations on deviation from predetermined performance thresholds used to trigger graded safety alerts, we suggest that many psychoactive substances produce alterations to biobehavioral processes including attentional and motor control, which affect performance indices in a manner already arguably captured by these technologies.

RESULTS

Using these existing frameworks, there is considerable potential to similarly catalogue the effect of many common intoxicants known to negatively affect driving ability. This will provide safety-relevant and practical biological models for the development of next-generation multimodal DMS that integrate ocular and physiological variables sensitive to the effects of common and emergent psychoactive substances.

CONCLUSION

These devices have tangible potential application across all areas of transportation, including aviation, rail, and all commercial and private vehicle systems.

Gaze Entropy Measures Reveal Alcohol-Induced Visual Scanning Impairment During Ascending and Descending Phases of Intoxication

OBJECTIVE

Visuospatial awareness is critical for everyday activities like driving. Higher order processes, such as visuospatial working memory (VSWM) and top-down modulation of gaze control, enable goal-driven visual scanning. Although available evidence suggests that alcohol differentially affects VSWM during the ascending and descending phases of the blood alcohol concentration (BAC) curve, it remains unclear whether such impact extends to a systemic disruption of visual scanning behavior.

METHOD

In a placebo-controlled and repeated-measures design, the present study investigated the influence of moderate alcohol intake (0.6 g/kg) on VSWM and gaze behavior by using gaze entropy measures to quantify visual scanning efficiency. Thirty-eight (18 female, 20 male) healthy participants completed a VSWM task across three consecutive sessions (baseline, ascending, descending) while their eye movements were simultaneously recorded.

RESULTS

Performance in VSWM was affected during the descending session, where response accuracy declined significantly. Stationary gaze entropy (SGE) and gaze transition entropy (GTE) measures significantly reduced during both ascending and descending sessions. Fixation rate and duration were also affected by alcohol, but only during the ascending session.

CONCLUSIONS

Reduction in SGE suggests a less explorative distribution of gaze, whereas low GTE is indicative of reduced visual scanning efficiency. These findings reflect the detrimental effects of alcohol on top-down control of gaze behavior, which may limit visual scanning efficiency. Deficits in visual scanning efficiency across the blood alcohol concentration curve may reduce visuospatial awareness and contribute to unintentional injuries during periods of intoxication.

P9: THE ROLE OF PROCALCITONIN IN SEPSIS

Purpose of Study

This study will discuss the pathogenesis of sepsis, procalcitonin as a diagnostic prognostic marker for sepsis, other biomarkers of sepsis and sepsis treatment.

Methods Used

as required.

Summary of Results

Sepsis is a systemic immune response to infection by microbial organisms. Its complications are one of the leading causes of mortality. Mortality rate in sepsis remains high despite the current advances in medical science. Serum biomarkers like procalcitonin may aid in the early diagnosis of sepsis and therapeutic intervention.Procalcitonin belongs to a class of molecules, called “hormokines,” given the hormonal origin of the protein and the inflammation-related functions of its propeptides. Procalcitonin is a potent amplifier of the inflammatory cascade. It has shown that it induces pro-inflammatory like effects on leukocytes (increased the expression of surface markers), increases leukocyte-derived cytokines and also augments nitric oxide. Procalcitonin was found to be a more accurate diagnostic parameter for sepsis. A systemic review and meta-analysis revealed that procalcitonin has a mean sensitivity of 77% and specificity of 79%. Elevated level of procalcitonin was found to be a better predictor of mortality and identify patients at higher risk of adverse outcomes.Procalcitonin is found to be superior to C-reactive protein, TNF-α, Interleukins and Lactate levels in terms of accuracy at identifying sepsis and assessing the severity of sepsis. Implementation of a procalcitonin-guided antibiotic therapy in clinical setting was associated with a reduced duration of antibiotic therapy in septic patients without compromising clinical or economical outcomes.

Conclusions

Procalcitonin has been proved to be more reliable biomarker in diagnosing sepsis and predicting clinical outcome. Integrating use of procalcitonin in the early golden hours of sepsis diagnosis and antibiotic stewardship program would be beneficial.

This review identified the association of procalcitonin and sepsis. There is still a need for better understanding of how procalcitonin fits in the immune response, therefore further studies should be towards exploring the immunological role of procalcitonin in sepsis.

Drivers' visual scanning impairment under the influences of alcohol and distraction: a literature review

Alcohol intoxication and distraction are two of the leading factors associated with impaired driving and fatalities, especially among younger drivers. However, it is currently unclear how these conditions affect mechanisms of visual attention considered essential for driving. The present article first reviews the literature to provide an overview of visual attention as it relates to driving. Secondly, the effects of alcohol and distraction on neurocognitive mechanisms of visual attention are summarised to provide a background which informs discussion of selected driving studies. Visual scanning impairment is identified as a consequence of both alcohol and distraction. Thus, experimental studies combining the use of simulated driving and eye tracking technologies are selected and critically reviewed to assess the relationship between eye movements and driving errors as possible indicators of visual scanning impairment. Seven of the eight studies selected investigated the effects of distraction while only one addressed alcohol. Evaluation of these studies suggests that distraction may affect visual scanning by increasing cognitive load which interferes with visual processing. The evidence for effects of alcohol on drivers' visual scanning capacity is currently scarce due to the lack of research with a specific focus on impairments of eye movement in intoxicated drivers. Lack of consistency between studies is identified as a current issue which makes it difficult to compare the results of different studies. Finally, we note that our strict selection of driving studies to avoid greater disparity between them is a limitation of the present review.

A population-based estimate of the burden of diarrhoeal illness in the United States: FoodNet, 1996-7

This study was performed to better understand and more precisely quantify the amount and burden of illness caused by acute diarrhoea in the United States today. A telephone-based population survey was conducted between 1 July, 1996, and 31 June, 1997, in sites of the Foodborne Diseases Active Surveillance Network (FoodNet). The overall prevalence of acute diarrhoea in the 4 weeks before interview was 11%, giving a rate of 1.4 episodes of diarrhoea per person per year. The rate of diarrhoeal illness defined as a diarrhoeal episode lasting longer than 1 day or which resulted in significant impairment of daily activities was 0.7 per person per year. It can be concluded that acute diarrhoea is common and represents a significant burden of illness in the United States. Our data on self-reported diarrhoea, when generalized to the entire nation, suggests 375 million episodes of acute diarrhoea each year in the United States. Many of these episodes are mild. However, our data also indicate that there are approximately 200 million episodes of diarrhoeal illness each year in the United States.

Prevalence of high-risk food consumption and food-handling practices among adults: a multistate survey, 1996 to 1997. The Foodnet Working Group

Risk factors for foodborne diseases include consumption of high-risk foods and unsanitary food-handling practices; however, little is known about the prevalence of these risk factors in the general population. A survey was done in five FoodNet sites (California, Connecticut, Georgia, Minnesota, Oregon) to determine the prevalence of these risk factors in the population. A total of 7,493 adults were interviewed by telephone between 1 July 1996 and 30 June 1997. Results showed that 1.5% drank raw milk, 1.9% ate raw shellfish, 18% ate runny egg, 30% preferred pink hamburger, 93% said they almost always washed their cutting board after cutting raw chicken, and 93% said they almost always washed their hands after handling raw meat or poultry, during 5 days before interview. The results differed by state and demographic group. Consumption of raw shellfish (3.2%) and undercooked hamburger (43%) were more common in Connecticut than other states. Raw milk consumption was more common among people who lived on a farm (8.6%) compared with people who lived in a city or urban area (1.1%). Preference for undercooked hamburger was more common among men (35%), young adults (18 to 25 years, 33%), people with college education (38%), and among people with household income of more than $100,000/year (49%). African-Americans were less likely to prefer undercooked hamburger compared to other racial groups (10% versus 30%). Young adults compared to older adults were less likely to wash their hands after handling raw chicken (88% versus 95%), and men washed their hands less often than women (89% versus 97%). Although there were statistical differences between demographic groups, they are insufficient to warrant targeted educational programs.

Incidence of foodborne illnesses reported by the foodborne diseases active surveillance network (FoodNet)-1997. FoodNet Working Group

In 1997, the Foodborne Diseases Active Surveillance Program (FoodNet) conducted active surveillance for culture-confirmed cases of Campylobacter, Escherichia coli O157, Listeria, Salmonella, Shigella, Vibrio, Yersinia, Cyclospora, and Cryptosporidium in five Emerging Infections Program sites. FoodNet is a collaborative effort of the Centers for Disease Control and Prevention's National Center for Infectious Diseases, the United States Department of Agriculture's Food Safety and Inspection Service, the Food and Drug Administration's Center for Food Safety and Applied Nutrition, and state health departments in California, Connecticut, Georgia, Minnesota, and Oregon. The population under active surveillance for foodborne infections was approximately 16.1 million persons or roughly 6% of the United States Population. Through weekly or monthly contact with all clinical laboratories in these sites, 8,576 total isolations were recorded: 2,205 cases of salmonellosis, 1,273 cases of shigellosis, 468 cases of cryptosporidiosis, 340 of E. coli O157:H7 infections, 139 of yersiniosis, 77 of listeriosis, 51 of Vibrio infections, and 49 of cyclosporiasis. Results from 1997 demonstrate that while there are regional and seasonal differences in reported incidence rates of certain bacterial and parasitic diseases, and that some pathogens showed a change in incidence from 1996, the overall incidence of illness caused by pathogens under surveillance was stable. More data over more years are needed to assess if observed variations in incidence reflect yearly fluctuations or true changes in the burden of foodborne illness.

The investigation and outcome of reported cases of elder abuse: the Forsyth County Aging Study

This study summarizes the outcome of all investigations of elder abuse conducted in Forsyth County, North Carolina, during a 3-year period ending December 1991. Of the 123 cases investigated, 23 were confirmed as elder abuse. There were no statistically significant differences in age, sex, race, living arrangements, mental status, mobility, or source of report between confirmed and unconfirmed cases. Unconfirmed compared to confirmed cases were more likely to reside in a nursing home and/or to be ill. The most frequently substantiated charge was exploitation of resources (46%). Only 3% of charges of physical abuse were substantiated. Among confirmed cases, 70% were offered and accepted protective services.