Advantages and Limitations of Naturalistic Study Designs and their Implementation in Alcohol Hangover Research

Alcohol hangover versus dehydration revisited: The effect of drinking water to prevent or alleviate the alcohol hangover

The alcohol hangover is a combination of negative mental and physical symptoms which can be experienced after a single episode of alcohol consumption, starting when blood alcohol concentration (BAC) approaches zero. A popular theory suggests that dehydration is the primary cause of alcohol hangover and that the consumption of water could alleviate hangover symptoms. Here, the current evidence on the relationship between hangover severity, thirst, and water consumption is summarized. The positive correlations of the amount of water consumed with both hangover severity and thirst suggest that both dehydration and the hangover are co-occurring after-effects of alcohol consumption. While hangovers were typically relatively enduring, dehydration effects were usually mild and short-lasting. Survey data revealed that water consumption during or directly after alcohol consumption had only a modest effect in preventing next-day hangover. Also, the amount of water consumed during hangover was not related to changes of hangover severity and thirst. Thus, water consumption was not effective to alleviate the alcohol hangover. Taken together, these data suggests that alcohol hangover and dehydration are two co-occurring but independent consequences of alcohol consumption.

Performance on a relational integration task is impaired during hangover

Recently, researchers have proposed an updated model of executive functions that includes relational integration, the mental ability to bind information into more complex structures. Hangover is known to disrupt other core components of executive functions, but little is known about how it influences relational integration. Therefore, this study aimed to investigate how hangover influences performance on a relational integration task. Twenty-seven participants completed an online relational integration task and mood- and emotion-regulation questionnaires during a hangover and no-hangover condition in this naturalistic design study. Results indicated that relational integration was impaired in hangover (p < 0.001, ηp2 = 0.562) relative to the no-hangover condition. In addition, participants experienced greater difficulties in regulating emotions (p < 0.001, d = 0.85) and lower mood (p < 0.001, d = 0.88) during hangover. These results suggest that relational integration is impaired in hangover and add weight to the argument that cognitive impairments in hangover may be due to the hangover-related impact on domain-general processing resources.

An evening of alcohol consumption negatively impacts next-day immune fitness in both hangover-sensitive drinkers and hangover-resistant drinkers

BACKGROUND

Survey research found poorer baseline immune fitness for self-reported hangover-sensitive drinkers compared to hangover-resistant drinkers. However, up to now a limited number of clinical studies revealed mixed results regarding the relationship between the concentrations of biomarkers of systemic inflammation in blood or saliva with hangover severity, and could not differentiate between hangover-sensitive drinkers and hangover-resistant drinkers. The aim of this study was to assess immune fitness and saliva biomarkers of systemic inflammation at multiple timepoints following an alcohol day and alcohol-free control day.

METHODS

The study had a semi-naturalistic design. In the evening before the test days, participants were not supervised. They could drink ad libitum drinking on the alcohol test day and refrained from drinking alcohol on the control day. Activities and behaviors on the alcohol and control day were reported the follow morning. On both test days, from 09:30 to 15:30, hourly assessments of immune fitness (single-item scale) and overall hangover severity (single-item scale) were made and saliva samples were collected for biomarker assessments.

RESULTS

N = 14 hangover-resistant drinkers and n = 15 hangover-sensitive drinkers participated in the study. The amount of alcohol consumed on the alcohol day did not significantly differ between the hangover-resistant group (mean (SD) of 13.5 (7.9) alcoholic drinks) and the hangover-sensitive group (mean (SD) of 12.4 (4.4) alcoholic drinks). All hangover-sensitive drinkers reported having a hangover following the alcohol day (overall hangover severity score 6.1 (on a 0-10 scale) at 09:30, gradually decreasing to 3.3 at 15:30), whereas the hangover-resistant drinkers reported no hangover. On the control day, immune fitness of the hangover-sensitive group was significantly poorer than the hangover-resistant group. On the alcohol day, both groups showed a significant reduction in immune fitness. The effect was evident throughout the day, but significantly more pronounced in the hangover-sensitive group than the hangover-resistant group. No significant differences between the groups were found at any time point on the two test days for saliva concentrations of Interleukin (IL)-1β, IL-6, IL-8, and tumor necrosis factor (TNF)-α.

CONCLUSIONS

Whereas hangover-sensitive drinkers reported a hangover following an alcohol day and hangover-resistant drinkers did not, both groups reported significantly reduced immune fitness throughout the day. However, the reduction in immune fitness among hangover-sensitive drinkers was significantly more pronounced in comparison to the hangover-resistant group.

Test-retest reliability of single-item assessments of immune fitness, mood, and quality of life

The use of single-item assessments is increasingly important and popular, as these enable quick real-time assessments in clinical practice or research. In this study we investigated the test-retest reliability of single-item assessments of mood ("stress", "anxiety", "depression", "fatigue", "loneliness", "being active", "optimism", and "happiness"), quality of life, and immune fitness in N = 108 participants. The analysis revealed high test-retest correlations between the single-item assessments (r = 0.67 to 0.90), moderate to excellent intraclass correlations (r = 0.672 to 0.889), and the Bland-Altman analysis revealed agreement between all test-retest assessments, except for depression. Taken together, it can be concluded that the single-item assessments of mood, quality and immune fitness have a good test-retest reliability. This strengthens the rationale for using these single item assessments.

Differences in Next-Day Adverse Effects and Impact on Mood of an Evening of Heavy Alcohol Consumption between Hangover-Sensitive Drinkers and Hangover-Resistant Drinkers

The combination of negative mental and physical symptoms which can be experienced after a single episode of alcohol consumption, starting when blood alcohol concentration (BAC) approaches zero, are collectively referred to as the alcohol hangover. Previous research revealed that 10 to 20% of drinkers claim not to experience next-day hangovers. Past studies were usually limited to single timepoint assessments. The aim of the current semi-naturalistic study was to compare the next-day effects of an evening of alcohol consumption of self-reported hangover-resistant drinkers (n = 14) with those of a group of self-reported hangover-sensitive drinkers (n = 15) at hourly timepoint throughout the day (09:30 until 15:30). Assessments of 23 hangover symptoms, mood (Profiles of Mood States-Short Form), and daytime sleepiness (Karolinska Sleepiness Scale) were made hourly after both an alcohol day and an alcohol-free control day. Additional morning assessments were made for mood (State-Trait Anxiety Inventory-Y, Beck’s Depression Inventory-II), risk-taking behavior (RT-18), past night sleep (Groningen Sleep Quality Scale), alcohol consumption, and activities during the test days. No significant differences were found regarding the amount of alcohol consumed and the total sleep time of the two groups. The hangover-sensitive group reported having a hangover as well as the presence of a variety of hangover-related symptoms, which were most severe in the morning and then gradually decreased during the day. The most frequently reported and most severe symptoms were sleepiness and fatigue, concentration problems, and headache. In contrast, the hangover-resistant group reported the absence of a hangover and the presence and severity of next-day symptoms did not significantly differ from the control day, except for increased fatigue and reduced vigor. The next-day effects on sleepiness-related complaints and vigor were significantly more pronounced among hangover-sensitive drinkers compared to hangover-resistant drinkers. In conclusion, contrary to hangover-resistant drinkers, hangover-sensitive drinkers report a variety of hangover symptoms that gradually ease during the day, but are still present in the afternoon.

Which therapist perceptions best predict client outcomes? A naturalistic examination

Examining associations between therapists' perceptions of therapy sessions and client-reported outcomes in naturalistic settings (real-life therapy settings) can provide valuable guidance for the assessment, treatment, and monitoring of clients. This study included data of 1334 sessions from 127 clients (86 individual and 41 couple cases) and 15 therapists, collected at a therapy training center. Clients reported their personal functioning and individual symptoms before each session. Therapists rated clients' participation, receptivity, session progress, goal progress, and therapeutic alliance at the end of each therapy session. Multilevel Structural Equation Modeling analyses revealed that therapist-rated client participation and goal progress predicted better personal functioning, beyond clients' previous personal functioning scores. In contrast, none of therapist-rated session variables predicted clients' individual symptoms, beyond previous symptom scores. Power analyses suggested sufficient statistical power to detect small effect sizes. Findings of the current study have clinical implications for treatment planning and progress monitoring.

Man flu is not a thing - Gender-specific secondary analysis of a prospective randomized-controlled trial for acute rhinosinusitis

BACKGROUND

'Man flu' is a popular term to describe hypersensitivity to acute rhinosinusitis (ARS) in men. While this pop-cultural description may influence the social perspective of ARS, so far, no prospective observational data on the gender-specific natural development of ARS is available.

METHODS

Secondary data analyses were performed from the placebo arm of a prospective, interventional phase IV clinical trial. Objective measurement of ARS symptoms were assessed with the Major Symptom Score (MSS), a clinician-rated assessment tool. The Sino-Nasal Outcome Test-22 (SNOT-22) was used for symptom self-report. Repeated measures analysis of variance (ANOVA) with gender as a group variable were used to investigate changes in MMS and SNOT-22 total score and subscales over time.

RESULTS

While MMS scores did not differ at baseline, women showed a significantly greater reduction than men with a medium effect size (p = .040) over time. In the patient-reported symptom score, women showed a significantly higher symptom load at baseline (p = .038), but also a significantly faster subjective improvement of symptoms than men during the course of time with a medium effect size (p = .020). However, when separately assessing the SNOT-22 subscales, a significant time*gender effect was only found for emotional symptoms (p = .047). No gender effect was found for neither nasal, otological, or sleep symptoms (all p > .05).

DISCUSSION

Although a certain gender difference was found both in the clinician- as well as patient-rated ARS symptoms, the hypothesis of a 'man flu' should be disregarded. Gender differences in ARS symptomatology should be carefully evaluated without stigmatizing symptom distress based on gender perceptions.

Adverse Drug Reactions in Relation to Clozapine Plasma Levels: A Systematic Review

Clozapine is the gold standard for treatment-resistant schizophrenia. Serious and even life-threatening adverse effects, mostly granulocytopenia, myocarditis, and constipation, are of great clinical concern and constitute a barrier to prescribing clozapine, thus depriving many eligible patients of a lifesaving treatment option. Interestingly, clozapine presents variable pharmacokinetics affected by numerous parameters, leading to significant inter- and intra-individual variation. Therefore, therapeutic drug monitoring of plasma clozapine levels confers a significant benefit in everyday clinical practice by increasing the confidence of the prescribing doctor to the drug and the adherence of the patient to the treatment, mainly by ensuring effective treatment and limited dose-related side effects. In the present systematic review, we aimed at identifying how a full range of adverse effects relates to plasma clozapine levels, using the Jadad grading system for assessing the quality of the available clinical evidence. Our findings indicate that EEG slowing, obsessive-compulsive symptoms, heart rate variability, hyperinsulinemia, metabolic syndrome, and constipation correlate to plasma clozapine levels, whereas QTc, myocarditis, sudden death, leucopenia, neutropenia, sialorrhea, are rather unrelated. Rapid dose escalation at the initiation of treatment might contribute to the emergence of myocarditis, or leucopenia. Strategies for managing adverse effects are different in these conditions and are discussed accordingly.

An on-premise study to investigate the effects of mixing alcohol with caffeinated beverages

OBJECTIVE

The purpose of this on-premise study was to determine if mixing alcohol with caffeinated mixers had an impact on objective and subjective intoxication.

METHODS

The study was conducted across eight drinking occasions in the City of Bristol, UK. Participants (N = 1041) were recruited outside popular night-time entertainment venues and interviewed regarding their alcohol consumption for that particular evening, including whether or not they had consumed caffeinated beverages with alcohol. Subjective intoxication was rated on an 11-point scale and objective intoxication determined with a breath alcohol test. Depending on their consumption on the night of the interview, participants also reported whether they consumed alcohol mixed with caffeinated mixers or alcohol-only on other consumption occasions.

RESULTS

Between-subjects analyses found that alcohol-caffeine consumers consumed more alcohol and had higher objective and subjective intoxication than those who consumed alcohol-only. These results remained significant regardless of whether or not they mixed alcohol with caffeinated mixers or consumed alcohol-only on the night of the interview. Within-subject analyses revealed that alcohol-caffeine consumers drank the same or less alcohol on alcohol-caffeine occasions compared to alcohol-only occasions.

CONCLUSIONS

These findings provide support that alcohol-caffeine use does not increase overall alcohol consumption, and may be one manifestation of a high risk-taking personality.

The Relationship between Alcohol Hangover Severity, Sleep and Cognitive Performance; a Naturalistic Study

Alcohol hangover (AH) has been associated with poor sleep due to the negative effects of alcohol intoxication on sleep quantity and sleep quality. The aim of the current study was to further explore the relationship between AH severity and sleep using a naturalistic study design. A further aim was to determine whether quantitative aspects of sleep were a mediating influence on the relationship between AH severity and cognitive performance. As part of the naturalistic study design, 99 drinkers were recruited following a night of drinking in an Australian state capital, with breath alcohol concentration (BrAC) measured as participants were leaving the entertainment district. The following morning at home, participants answered online questions regarding their drinking behaviour on the previous evening, current AH symptoms and sleep quality. Participants also completed an online version of the Trail-Making Test B (TMT-B) to assess cognitive performance. The findings reveal the duration of nightly awakenings to be negatively related to six individual AH symptoms as well as overall AH severity. The number of nightly awakenings, sleep quality and total sleep time correlated with four AH symptoms including overall AH severity. Total AH severity accounted for a moderate amount of variance (11%) in the time to complete the TMT-B. These findings confirm that alcohol consumption negatively affects sleep, which is related to higher next-day hangover severity ratings and poorer cognitive performance.

The Effects of a Digital Mental Health Intervention in Adults With Cardiovascular Disease Risk Factors: Analysis of Real-World User Data

Background

The American Heart Association has identified poor mental health as a key barrier to healthy behavior change for those with cardiovascular disease (CVD) risk factors such as high blood pressure, high cholesterol, and diabetes. Digital mental health interventions, like those delivered via the internet to computers or smartphones, may provide a scalable solution to improving the mental and physical health of this population. Happify is one such intervention and has demonstrated evidence of efficacy for improving aspects of mental health in both the general population and in users with chronic conditions.

Objective

The objectives of this analysis of real-world data from Happify users with self-reported CVD risk factors, including high blood pressure and cholesterol, diabetes, and heart disease, were to examine whether these users would report improvements in subjective well-being and anxiety over time (H1) and use of Happify as recommended would be associated with significantly greater improvement in subjective well-being and anxiety over time compared to less-than-recommended usage (H2).

Methods

Data were obtained from existing Happify users who reported the aforementioned CVD risk factors. The sample included 1803 users receiving at least 6 weeks’ exposure to Happify (ranging from 42 days to 182 days) who completed at least one activity and two assessments within the app during that time. Subjective well-being was assessed with the Happify Scale, a 9-item measure of positive emotionality and life satisfaction, and anxiety was assessed with the Generalized Anxiety Disorder 2 (GAD-2). To evaluate H1, changes over time in both outcomes were assessed using mixed effects linear regression models, controlling for demographics and usage. For H2, an interaction term was added to the models to assess whether usage as recommended was associated with greater improvement over time.

Results

Both hypotheses were supported. For both the Happify scale and GAD-2, the initial multivariable model without an interaction demonstrated an effect for time from baseline, and the addition of the interaction term between time and recommended use was significant as well.

Conclusions

This analysis of real-world data provides preliminary evidence that Happify users with self-reported CVD risk factors including high blood pressure or cholesterol, diabetes, and heart disease experienced improved well-being and anxiety over time and that those who used Happify as recommended experienced greater improvements in these aspects of mental health than those who completed fewer activities. These findings extend previous research, which demonstrated that engagement with Happify as recommended was associated with improved well-being among physically healthy users and in those with chronic conditions, to a new population for whom mental health is especially critical: those at risk of developing CVD.

Behavioural activation and trial-based cognitive therapy may be beneficial to reduce suicidal ideation in major depressive disorder: A post hoc study from a clinical trial

WHAT IS KNOWN AND OBJECTIVE

The suicidality spectrum is a clinical challenge because of the difficulty of its management and its association with mortality. Few studies have investigated psychotherapies for reducing the components of suicidality. In this study, we compared the effect of behavioural activation (BA), trial-based cognitive therapy (TBCT) - both added to antidepressant (AD) treatment - and treatment as usual (TAU) in mitigating suicidal ideation in patients with major depressive disorder (MDD).

METHODS

A post hoc study was conducted with data from a randomized clinical trial. Secondary analyses compared the treatments using scores from the items that evaluated suicidal ideation with the HAM-D (HAM-D-3) and BDI (BDI-9). A composite measurement was constructed by summing the scores from the two items (HAM-D-3 plus BDI-9).

RESULTS AND DISCUSSION

Seventy-six patients were analysed (BA + AD = 24; TBCT + AD = 26 and TAU = 26). In HAM-D-3, the BA + AD group showed a statistically greater reduction than the TAU group. In BDI-9, the three groups did not show significant differences. In the HAM-D-3 plus BDI-9, TBCT + AD reduced ideations more than the TAU group. There were no differences among the psychotherapies in any of the measures. Sensitivity analyses showed improvement in suicidal ideation in both psychotherapies compared to TAU.

WHAT IS NEW AND CONCLUSION

This is one of the few studies that evaluated the effect of BA and TBCT in lowering suicidal ideation. Adding these therapies to ADs seems to decrease suicidal ideation. We suggest the possible beneficial effects of BA and TBCT in the management of suicidal ideation in patients with recurrent MDD. Our findings need further studies to confirm these results.

The 5HTOL/5HIAA Ratio as a Biomarker of Alcohol Hangover

Assessment of the presence and severity of alcohol hangovers relies on the subjective method of self-report. Therefore, there is a need of adequate biomarkers that (1) correlate significantly with hangover severity, and (2) correspond to the level of hangover-related performance impairment objectively. In this naturalistic study, n = 35 social drinkers participated. Urine samples were obtained the morning after alcohol consumption and after an alcohol-free control day. Concentrations of 5-hydroxytryptophol (5-HTOL), 5-hydroxyindoleacetic acid (5-HIAA) and the 5-HTOL/5-HIAA ratio were determined. The results confirm previous findings that 5-HTOL and the 5HTOL/5-HIAA ratio are useful biomarkers of recent alcohol consumption. Significant correlations were found with the amount of alcohol consumed, total drink time, and estimated BAC. However, urine concentrations of 5-HTOL and 5-HIAA (and their ratio 5HTOL/5-HIAA) did not significantly correlate with hangover severity. In conclusion, urine 5-HTOL, 5-HIAA, and the 5HTOL/5-HIAA ratio cannot be considered to be suitable biomarkers of alcohol hangover.

Immune Responses after Heavy Alcohol Consumption: Cytokine Concentrations in Hangover-Sensitive and Hangover-Resistant Drinkers

This study investigated immunological changes during an alcohol hangover, and the possible difference between hangover-resistant and hangover-sensitive drinkers in terms of immune reactivity. Using a semi-naturalistic design, N = 36 healthy social drinkers (18 to 30 years old) provided saliva samples on a control day (after drinking no alcohol) and on a post-alcohol day. Hangover severity was rated directly after saliva collection. Cytokine concentrations, interleukin (IL)-1β, IL-6, IL-8, IL-10 and tumor necrosis factor (TNF)-α, and hangover severity were compared between both test days and between hangover-sensitive and -resistant drinkers. Data from N = 35 drinkers (17 hangover-sensitive and 18 hangover-resistant) were included in the statistical analyses. Relative to the control day, there were significant increases in saliva IL-6 and IL-10 concentrations on the post-alcohol day. No significant differences in cytokine concentrations were found between hangover-sensitive and hangover-resistant drinkers, nor did any change in cytokine concentration correlate significantly with hangover severity. In line with previous controlled studies assessing cytokines in blood, the current naturalistic study using saliva samples also demonstrated that the immune system responds to high-level alcohol intake. However, further research is warranted, as, in contrast to previous findings in blood samples, changes in saliva cytokine concentrations did not differ significantly between hangover-sensitive and hangover-resistant drinkers, nor did they correlate significantly with hangover severity.

The Use of Single-Item Ratings Versus Traditional Multiple-Item Questionnaires to Assess Mood and Health

Collecting real-world evidence via ‘at home’ assessments in ambulatory patients or healthy volunteers is becoming increasingly important, both for research purposes and in clinical practice. However, given the mobile technology that is frequently used for these assessments, concise assessments are preferred. The current study compared single-item ratings with multiple-item subscale scores of the same construct, by calculating the corresponding Bland and Altman 95% limits of agreement interval. The analysis showed that single-item ratings are usually in good agreement with assessments of their corresponding subscale. In the case of more complex multimodal constructs, single-item assessments were much less often in agreement with multiple-item questionnaire outcomes. The use of single-item assessments is advocated as they more often incorporate assessments of all aspects of a certain construct (including the presence, severity, and impact of the construct under investigation) compared to composite symptom scores.

The Alcohol Hangover Research Group: Ten Years of Progress in Research on the Causes, Consequences, and Treatment of the Alcohol Hangover

The alcohol hangover is defined as the combination of negative mental and physical symptoms, which can be experienced after a single episode of alcohol consumption, starting when blood alcohol concentration (BAC) approaches zero. Here, we present the book "The alcohol hangover: causes, consequences, and treatment", written to celebrate the 10th anniversary of the Alcohol Hangover Research Group (AHRG), summarizing recent advances in the field of alcohol hangover research.

Does Alcohol Hangover Affect Emotion Regulation Capacity? Evidence From a Naturalistic Cross-Over Study Design

AIMS

The aim of this study was to investigate the effects of alcohol hangover on emotion regulation.

METHODS

Forty-five non-smoking, healthy participants aged between 18 and 30 years completed a lab-based emotion regulation task assessing cognitive reappraisal and an emotion regulation questionnaire (State-Difficulties in Emotion Regulation Scale [S-DERS]) when hungover (morning following a night of heavy drinking) and under a no-hangover condition in a naturalistic, within-subjects design study.

RESULTS

Participants reported poorer emotion regulation overall (P < 0.001, d = 0.75), and for the subscales 'Non-Acceptance', 'Modulation' and 'Clarity' (Ps ≤ 0.001, ds ≥ 0.62), but not 'Awareness' on the S-DERS, in the hangover versus the no-hangover condition. Hangover did not impair emotion regulation ability as assessed using the lab-based task (Ps ≥ 0.21, ds ≤ 0.40), but there was a general negative shift in valence ratings (i.e. all images were rated more negatively) in the hangover relative to the no-hangover condition (P < 0.001, d = 1.16).

CONCLUSION

These results suggest that emotion regulation in everyday life and emotional reactivity may be adversely affected by alcohol hangover, but some emotion regulation strategies (e.g. deliberate cognitive reappraisal) may be unaffected.

University Students' Hangover May Affect Cognitive Research

University students are the most employed category of participants in cognitive research. However, researchers cannot fully control what their participants do the night before the experiments (e.g., consumption of alcohol) and, unless the experiment specifically concerns the effects of alcohol consumption, they often do not ask about it. Despite previous studies demonstrating that alcohol consumption leads to decrements in next-day cognitive abilities, the potential confounding effect of hangover on the validity of cognitive research has never been addressed. To address this issue, in the present study, a test-retest design was used, with two groups of university students: at T0, one group was constituted by hungover participants, while the other group was constituted by non-hungover participants; at T1, both groups were re-tested in a non-hangover state. In particular, the tests used were two versions of a parity judgment task and an arithmetic verification task. The results highlight that: (a) the response times of university students experiencing a hangover are significantly slower than those of non-hangover students and (b) the response times of hungover students are slower than those of the same students when re-tested in a non-hangover state. Additionally, it was also observed that the prevalence of hungover students in the university campus varies depending on the day of the week, with a greater chance of enrolling hungover participants on specific days. In light of the latter result, the recruitment of university students as participants in cognitive experiments might lead researchers to erroneously attribute their results to the variables they are manipulating, ignoring the effects of the potential hangover state.

Prevalence of Hangover Resistance According to Two Methods for Calculating Estimated Blood Alcohol Concentration (eBAC)

Hangover resistance may be linked to an increased risk of continuing harmful drinking behaviours as well as involvement in potentially dangerous daily activities such as driving while hungover, mainly due to the absence of negative consequences (i.e., hangover symptoms) the day after alcohol consumption. The aim of this study was to examine the occurrence of claimed alcohol hangover resistance relative to estimated blood alcohol concentration (eBAC). A total of 1198 participants completed an online survey by answering questions regarding their demographics, alcohol consumption and occurrence of hangover. Two methods were used to calculate eBAC, one based on the modified Widmark Equation (N = 955) and the other from an equation averaging the total body water (TBW) estimates of Forrest, Watson, Seidl, Widmark and Ulrich (males only) (N = 942). The percentage of participants who claimed to be hangover resistant decreased rapidly with increasing eBAC and only a small number of hangover resistant drinkers remained at higher eBACs. Comparisons of the eBACs calculated by the two methods revealed significantly higher BACs when using the modified Widmark equation. These findings suggest that additional research for eBAC calculations is needed to improve accuracy and comprehensiveness of these equations for future alcohol hangover research.

The Impact of Mood and Subjective Intoxication on Hangover Severity

The aim of this study was to investigate whether baseline mood and/or mood while drinking have an impact on alcohol hangover severity. A survey was held among N = 331 young adults (mean age = 23.6 years, range = 18-35 years). Demographics, alcohol consumption, subjective intoxication, and hangover severity were assessed for the past three days. In addition, mood (baseline, while drinking, and during hangover) was also assessed. N = 143 participants reported to be hungover on the day of assessment, N = 122 participants reported to have been hungover the previous day ('yesterday'), and N = 87 participants reported to have been hungover two days before the assessment ('2 days ago'). The analyses revealed that baseline mood and mood while drinking had no relevant effect on the amount of consumed alcohol and did not significantly contribute to hangover severity. However, hangover severity was associated with significantly increased negative affect, particularly with higher levels of subjective stress on the day of the hangover.

Effects of Rapid Recovery on Alcohol Hangover Severity: A Double-Blind, Placebo-Controlled, Randomized, Balanced Crossover Trial

The aim of this study was to evaluate the efficacy of putative hangover treatment, Rapid Recovery, in mitigating alcohol hangover (AH) symptom severity. Using a double-blind, randomized, placebo-controlled, balanced crossover design, 20 participants attended the laboratory for two evenings of alcohol consumption, each followed by morning assessments of AH severity. Participants were administered Rapid Recovery and placebo on separate visits. In the first testing visit, participants self-administered alcoholic beverages of their choice, to a maximum of 1.3 g/kg alcohol. Drinking patterns were recorded and replicated in the second evening testing visit. In the morning visits, AH severity was assessed using questionnaires measuring AH symptom severity and sleep quality, computerized assessments of cognitive functioning as well as levels of blood biomarkers of liver function (gamma-glutamyl transferase (GGT)) and inflammation (high-sensitive C-reactive protein (hs-CRP)). There were no differences in the blood alcohol concentrations (BAC) obtained in the Rapid Recovery (mean = 0.096%) and placebo (mean = 0.097%) conditions. Participants reported significantly greater sleep problems in the Rapid Recovery compared to placebo condition, although this difference was no longer significant following Bonferroni's correction. There were no other significant differences between Rapid Recovery and placebo. These data suggest that Rapid Recovery has no significant effect on alcohol hangover nor on associated biomarkers.

The Association between Ethanol Elimination Rate and Hangover Severity

Assessments in blood and saliva suggests that the amount of ethanol present in the first hours after alcohol consumption and into the following morning is associated with hangover severity. The current analysis determines how ethanol elimination rate is related to hangover severity reported throughout the day. n = 8 subjects participated in two studies. The first was a naturalistic study comprising an evening of alcohol consumption. Hangover severity was assessed hourly from 10 a.m. to 4 p.m., using a 1-item hangover severity scale ranging from 0 (absent) to 10 (extreme). The second study comprised a highly controlled alcohol challenge to reach a breath alcohol concentration (BrAC) of 0.05%. Breathalyzer tests were conducted every 5 min until BrAC reached zero. The ethanol elimination rate, expressed in BrAC%/hour, was computed by dividing the peak BrAC (%) by the time to BrAC of zero (h). At 11:00, 13:00, and 14:00, there were significant negative partial correlations, controlling for estimated BrAC, between ethanol elimination rate and hangover severity. The findings suggest that drinkers with a faster ethanol elimination rate experience less severe hangovers. The observations should be confirmed in a larger sample of subjects who participate in a single study that assesses both hangover severity and ethanol elimination rate.

The Impact of Alcohol Hangover on Simulated Driving Performance During a 'Commute to Work'-Zero and Residual Alcohol Effects Compared

Driving is increasing across the world and road traffic accidents are a major cause of serious injuries and fatalities. The link between alcohol consumption and impaired driving has long been established and has led to legislation in many countries, with enforcement of legal limits based on blood alcohol concentration levels. Alcohol hangover research is an emerging field with a range of laboratory and naturalistic studies now clearly demonstrating the significant impairments that can result from hangover, even when alcohol levels are measured at or close to zero the day following a social drinking occasion. Driving is a commonplace activity but requires competency with a range of complex and potentially demanding tasks. Driving impaired can have serious consequences, including death and serious injury. There have been only limited alcohol hangover driving studies. The studies presented examined the consequences of alcohol hangover with a driving simulator contrasting a group with zero residual alcohol (N = 26) next day and another with residual alcohol (N = 26) assessed with breathalyzer in the morning before undertaking a 20 min commute to work. All participants completed a morning drive after a night without alcohol consumption and another after a night of social drinking. The driving scenarios were relatively demanding including traffic and pedestrians, traffic lights and other potential hazards in a mixed rural and urban journey. Subjective hangover and workload were assessed in addition to a range of driving performance variables, including divided attention, steering control and driving violations. Analyses contrasted driving in the no alcohol condition with the residual alcohol condition. The combined groups data (N = 52) was contrasted with the zero and residual alcohol groups. Significant contrasts were found for a range of driving measures, including divided attention, vehicle control, and driving violations as well as perceived workload. The pattern of impairment was broadly similar across both groups, indicating that whether or not residual alcohol was present, consistent driving impairment was seen. The relatively high number of significant variables may reflect the increased cognitive demand of the 20 min commute drive including busy and complex urban environments. This was also reflected in the significant increase in perceived workload recorded across the 6 dimensions of the National Aeronautics and Space Administration Task Load Index (NASA-TLX). Associations between subjective measures and driving performance with hangover suggested a potential lack of awareness of impairment, though were limited in number. The overall findings indicate that the levels of impairment seen reflect those seen with alcohol impaired driving, even when breath alcohol is zero.

The Effects of Alcohol Hangover on Executive Functions

Recent research has suggested that processes reliant on executive functions are impaired by an alcohol hangover, yet few studies have investigated the effect of hangovers on core executive function processes. Therefore, the current study investigated the effect of hangovers on the three core components of the unity/diversity model of executive functions: the ability to switch attention, update information in working memory, and maintain goals. Thirty-five 18-to-30-year-old non-smoking individuals who reported experiencing a hangover at least once in the previous month participated in this study. They completed tasks measuring switching (number-switching task), updating (n-back task), and goal maintenance (AX Continuous Performance Test, AX-CPT) whilst experiencing a hangover and without a hangover in a 'naturalistic' within-subjects crossover design. Participants made more errors in the switching task (p = 0.019), more errors in both the 1- (p < 0.001) and 2-back (p < 0.001) versions of the n-back, and more errors in the AX-CPT (p = 0.007) tasks when experiencing a hangover, compared to the no-hangover condition. These results suggest that an alcohol hangover impairs core executive function processes that are important for everyday behaviours, such as decision-making, planning, and mental flexibility.

Alcohol Hangover and Multitasking: Effects on Mood, Cognitive Performance, Stress Reactivity, and Perceived Effort

The aim of this study was to examine the effects of hangover on mood, multitasking ability, and psychological stress reactivity to cognitive demand. Using a crossover design and semi-naturalistic methodology, 25 participants attended the laboratory in the morning following a night of (i) alcohol abstinence and (ii) alcohol self-administration during a typical night out (with order counterbalanced across participants). They completed a four-module multitasking framework (MTF, a widely used laboratory stressor) and a battery of questionnaires assessing mood, hangover symptom severity, and previous night’s sleep. The effects of the MTF on mood and perceived workload were also assessed. Participants in the hangover condition reported significantly lower alertness and contentment coupled with a higher mental fatigue and anxiety. Multitasking ability was also significantly impaired in the hangover condition. Completion of the cognitive stressor increased reported levels of mental demand, effort, and frustration, and decreased perceived level of performance. MTF completion did not differentially affect mood. Lastly, participants rated their sleep as significantly worse during the night prior to the hangover compared with the control condition. These findings confirm the negative cognitive and mood effects of hangover on mood. They also demonstrate that hangover is associated with greater perceived effort during task performance.

The Effects of Alcohol Hangover on Mood and Performance Assessed at Home

The current study evaluated the next day consequences of a social night of drinking compared to a no alcohol night, with standardised mood and portable screen-based performance measures assessed in the morning at participants' homes, and a breathalyser screen for zero alcohol. A mixed sex group (n = 20) took part in the study. Participants reported consuming on average 16.9 units (135 g) alcohol, resulting in a hangover rating of 60 (out of 100) compared to 0.3 following the no alcohol night. Statistical significance comparisons contrasting the hangover with the no alcohol condition revealed an increase in negative mood and irritability during hangover and an (unexpected) increase in risk and thrill seeking. Performance scores showed an overall slowing of responses across measures, but with less impact on errors. The results support the description of hangover as a general state of cognitive impairment, reflected in slower responses and reduced accuracy across a variety of measures of cognitive function. This suggests a general level of impairment due to hangover, as well as increased negative mood. The use of a naturalistic design enabled the impact of more typical levels of alcohol associated with real life social consumption to be assessed, revealing wide ranging neurocognitive impairment with these higher doses. This study has successfully demonstrated the sensitivity of home-based assessment of the impact of alcohol hangover on a range of subjective and objective measures. The observed impairments, which may significantly impair daily activities such as driving a car or job performance, should be further investigated and taken into account by policy makers.

The Effects of SJP-001 on Alcohol Hangover Severity: A Pilot Study

Background. Despite a clear market need and many hangover products available, currently there is no hangover treatment that is supported by substantial scientific evidence demonstrating its efficacy and safety. A pilot study was conducted to investigate the effects of a potential new hangover treatment, SJP-001, and its constituents (220 mg naproxen and 60 mg fexofenadine) on hangover severity. Methods. N = 13 healthy social drinkers (36.3 ± 8.9 years old) participated in a double-blind, factorial design, cross-over study. On each test day, they consumed their own choice of alcohol up to a self-reported level sufficient to elicit a next-day hangover. Treatments were administered prior to onset of drinking. Next morning, hangover severity was assessed with the Acute Hangover Scale (AHS). Subjects were included in the efficacy analysis only if they reported a hangover after placebo. Results. N = 5 subjects (60% male, 35.2 ± 9.0 years old) were included in the analysis. They consumed a mean (SD) of 4.6 ± 1.1 units of alcohol and had an average peak breath alcohol concentration (BrAC) of 0.065% across conditions. Compared to placebo, SJP-001 significantly improved the AHS overall hangover severity score (0.8 ± 0.3 versus 1.5 ± 0.9, p = 0.042). Compared to placebo, SJP-001 also reduced scores on the individual item ‘hangover’, although the observed improvement (−1.6) did not reach statistical significance (p = 0.102). The differences from placebo after naproxen alone and fexofenadine alone were not statistically significant. SJP-001 also improved scores for the individual hangover symptoms tired, thirsty, headache, dizziness, nausea, and loss of appetite, but these effects did not reach statistical significance. Discussion. Compared to placebo, SJP-001 significantly reduced overall hangover severity. The effects of SJP-001 should be further examined in a double-blind, placebo-controlled trial with a larger sample size and controlled administration of sufficient amounts of alcohol to provoke a more substantial alcohol hangover.

Alcohol Hangover Differentially Modulates the Processing of Relevant and Irrelevant Information

Elevated distractibility is one of the major contributors to alcohol hangover-induced behavioral deficits. Yet, the basic mechanisms driving increased distractibility during hangovers are still not very well understood. Aside from impairments in attention and psychomotor functions, changes in stimulus-response bindings may also increase responding to distracting information, as suggested by the theory of event coding (TEC). Yet, this has never been investigated in the context of alcohol hangover. Therefore, we investigated whether alcohol hangover has different effects on target-response bindings and distractor-response bindings using a task that allows to differentiate these two phenomena. A total of n = 35 healthy males aged 19 to 28 were tested once sober and once hungover after being intoxicated in a standardized experimental drinking setting the night before (2.64 gr of alcohol per estimated liter of body water). We found that alcohol hangover reduced distractor-response bindings, while no such impairment was found for target-response bindings, which appeared to be unaffected. Our findings imply that the processing of distracting information is most likely not increased, but in fact decreased by hangover. This suggests that increased distractibility during alcohol hangover is most likely not caused by modulations in distractor-response bindings.

Sensitivity to Experiencing Alcohol Hangovers: Reconsideration of the 0.11% Blood Alcohol Concentration (BAC) Threshold for Having a Hangover

The 2010 Alcohol Hangover Research Group consensus paper defined a cutoff blood alcohol concentration (BAC) of 0.11% as a toxicological threshold indicating that sufficient alcohol had been consumed to develop a hangover. The cutoff was based on previous research and applied mostly in studies comprising student samples. Previously, we showed that sensitivity to hangovers depends on (estimated) BAC during acute intoxication, with a greater percentage of drinkers reporting hangovers at higher BAC levels. However, a substantial number of participants also reported hangovers at comparatively lower BAC levels. This calls the suitability of the 0.11% threshold into question. Recent research has shown that subjective intoxication, i.e., the level of severity of reported drunkenness, and not BAC, is the most important determinant of hangover severity. Non-student samples often have a much lower alcohol intake compared to student samples, and overall BACs often remain below 0.11%. Despite these lower BACs, many non-student participants report having a hangover, especially when their subjective intoxication levels are high. This may be the case when alcohol consumption on the drinking occasion that results in a hangover significantly exceeds their "normal" drinking level, irrespective of whether they meet the 0.11% threshold in any of these conditions. Whereas consumers may have relative tolerance to the adverse effects at their "regular" drinking level, considerably higher alcohol intake-irrespective of the absolute amount-may consequentially result in a next-day hangover. Taken together, these findings suggest that the 0.11% threshold value as a criterion for having a hangover should be abandoned.

Relationship between Alcohol Hangover and Physical Endurance Performance: Walking the Samaria Gorge

Alcohol hangover is a potentially debilitating state. Several studies have demonstrated that it does not seem to impair strength or short-term endurance, but its effects on continuous exercise performance/long-term endurance have never been investigated. Therefore, the aim of the current study was to assess hiking performance of participants who walked the 15.8 km Samaria Gorge in Crete, Greece. Participants completed a survey in the morning before walking the Gorge, and in the afternoon after completion of the walk. Demographics, data on previous evening alcohol consumption, sleep, hangover symptoms, and walking performance were assessed. Data from N = 299 participants with a mean (SD) age of 38.9 (11.0) years were analyzed. N = 223 participants (74.6%) consumed alcohol the evening before walking the Samaria Gorge, and N = 176 (78.9%) of those reported a hangover. They consumed a mean (SD) of 3.0 (1.8) alcoholic drinks (10 g alcohol each) with a corresponding next-morning hangover severity of 4.6 (2.4) on a 0–10 scale. Participants with a hangover reported feeling significantly more exhausted after the walk compared to participants with no hangover. The groups did not significantly differ in duration of the walk, and the number and duration of breaks. Overall hangover severity, assessed either before, during, or after walking the Samaria Gorge was not significantly correlated with any walking outcome. In conclusion, hungover participants experienced significantly more exhaustion when performing physical activity at the same level as non-hungover participants.