Estimating alcohol content of drinks: common errors in applying the unit system

Gender-related disparities in the frequencies of PD-1 and PD-L1 positive peripheral blood T and B lymphocytes in patients with alcohol-related liver disease: a single center pilot study

Background

Exposure to excessive alcohol consumption dysregulates immune signaling. The programed cell death 1 (PD-1) receptor and its ligand PD-L1 play a critical role in the protection against immune-mediated tissue damage. The aim of our study was evaluation of the PD-1/PDL-1 expression on peripheral T and B lymphocytes, its correlation with markers of inflammation and the severity of liver dysfunction in the course of alcohol-related liver disease (ALD).

Material and Methods

Fifty-six inpatients with ALD (38 males, 18 females, aged 49.23 ± 10.66) were prospectively enrolled and assigned to subgroups based on their: (1) gender, (2) severity of liver dysfunction (Child-Pugh, MELD scores, mDF), (3) presence of ALD complications, and followed for 30 days. Twenty-five age- and gender-matched healthy volunteers served as the control group. Flow cytometric analysis of the PD-1/PD-L1 expression on peripheral lymphocyte subsets were performed.

Results

General frequencies of PD-1/PD-L1 positive T and B subsets did not differ between the ALD and control group. When patients were analyzed based on their gender, significantly higher frequencies of PD1/PD-L1 positive B cells in ALD females compared to controls were observed. ALD females presented with significantly higher frequencies of PD-1+ and PD-L1+ B cells, as well as PD-L1+ all T cell subsets in comparison with ALD males. The same gender pattern of the PD-1/PDL1 expression was found in the subgroups with mDF > 32 and MELD > 20. No correlations of PD-1+ and PD-L1+ lymphocyte percentages with mDF, CTP and MELD scores, nor with complications of ALD were observed. Significant correlations of PD-L1 positive B cell frequencies with conventional markers of inflammation were found.

Conclusions

Gender-related differences in the frequencies of PD-1/PD-L1 positive T and B cells were observed in patients with ALD. Upregulation of PD-1+/PD-L1+ lymphocytes paralleled both the severity of alcoholic hepatitis and liver dysfunction in ALD females.

Can student health professionals accurately estimate alcohol content in commonly occurring drinks?

OBJECTIVES

Correct identification of alcohol as a contributor to, or comorbidity of, many psychiatric diseases requires health professionals to be competent and confident to take an accurate alcohol history. Being able to estimate (or calculate) the alcohol content in commonly consumed drinks is a prerequisite for quantifying levels of alcohol consumption. The aim of this study was to assess this ability in medical and nursing students.

METHODS

A cross-sectional survey of 891 medical and nursing students across different years of training was conducted. Students were asked the alcohol content of 10 different alcoholic drinks by seeing a slide of the drink (with picture, volume and percentage of alcohol by volume) for 30 s.

RESULTS

Overall, the mean number of correctly estimated drinks (out of the 10 tested) was 2.4, increasing to just over 3 if a 10% margin of error was used. Wine and premium strength beers were underestimated by over 50% of students. Those who drank alcohol themselves, or who were further on in their clinical training, did better on the task, but overall the levels remained low.

CONCLUSIONS

Knowledge of, or the ability to work out, the alcohol content of commonly consumed drinks is poor, and further research is needed to understand the reasons for this and the impact this may have on the likelihood to undertake screening or initiate treatment.

Alcohol Policy: Gaps between Legislative Action and Current Research

This paper compares alcohol policies under debate in U.S. state legislatures with policies that have been the focus of research attention. We reviewed the research literature to identify empirical studies of each policy and types of outcome variables analyzed. The two most evaluated alcohol control policies are the minimum legal drinking age and excise tax. Eight other policies had 20 or more studies evaluating them. The remaining alcohol policies received little attention in the research literature. Alcohol consumption and traffic crashes were the most frequent outcomes used in alcohol policy studies. Most studies evaluated policy changes at the state or national level, with few studies of local or institutional policies. During 1997 some 463 alcohol control bills were introduced at state legislatures. Many specific alcohol policies under debate in state legislatures have little research evidence to guide policy decision-making, pointing to areas where future research is needed.

Prognostic Significance of the Systemic Inflammatory and Immune Balance in Alcoholic Liver Disease with a Focus on Gender-Related Differences

Objectives

Mechanisms of immune regulation in alcoholic liver disease (ALD) are still unclear. The aim of our study was to determine an impact of Th17 / regulatory T (Treg) cells balance and its corresponding cytokine profile on the ALD outcome. Possible gender-related differences in the alcohol-induced inflammatory response were also assessed.

Materials and Methods

147 patients with ALD were prospectively recruited, assigned to subgroups based on their gender, severity of liver dysfunction and presence of ALD complications at admission, and followed for 90 days. Peripheral blood frequencies of Th17 and Treg cells together with IL-1beta, IL-6, IL-17A, IL-23, and TGF-beta1 levels were investigated. Flow cytometry was used to identify T cell phenotype and immunoenzymatic ELISAs for the corresponding cytokine concentrations assessment. Multivariable logistic regression was applied in order to select independent predictors of advanced liver dysfunction and the disease complications.

Results

IL-17A, IL-1beta, IL-6 levels were significantly increased, while TGF-beta1 decreased in ALD patients. The imbalance with significantly higher Th17 and lower Treg frequencies was observed in non-survivors. IL-6 and TGF-beta1 levels differed in relation to patient gender in ALD group. Concentrations of IL-6 were associated with the severity of liver dysfunction, development of ALD complications, and turned out to be the only independent immune predictor of 90-day survival in the study cohort.

Conclusions

We conclude that IL-6 revealed the highest diagnostic and prognostic potential among studied biomarkers and was related to the fatal ALD course. Gender-related differences in immune regulation might influence the susceptibility to alcohol-associated liver injury.

Association of serum adiponectin, leptin, and resistin concentrations with the severity of liver dysfunction and the disease complications in alcoholic liver disease

Background and aims. There is growing evidence that white adipose tissue is an important contributor in the pathogenesis of alcoholic liver disease (ALD). We investigated serum concentrations of total adiponectin (Acrp30), leptin, and resistin in patients with chronic alcohol abuse and different grades of liver dysfunction, as well as ALD complications. Materials and Methods. One hundred forty-seven consecutive inpatients with ALD were prospectively recruited. The evaluation of plasma adipokine levels was performed using immunoenzymatic ELISA tests. Multivariable logistic regression was applied in order to select independent predictors of advanced liver dysfunction and the disease complications. Results. Acrp30 and resistin levels were significantly higher in patients with ALD than in controls. Lower leptin levels in females with ALD compared to controls, but no significant differences in leptin concentrations in males, were found. High serum Acrp30 level revealed an independent association with advanced liver dysfunction, as well as the development of ALD complications, that is, ascites and hepatic encephalopathy. Conclusion. Gender-related differences in serum leptin concentrations may influence the ALD course, different in females compared with males. Serum Acrp30 level may serve as a potential prognostic indicator for patients with ALD.

Understanding standard drinks and drinking guidelines

INTRODUCTION AND AIMS

For consumers to follow drinking guidelines and limit their risk of negative consequences they need to track their ethanol consumption. This paper reviews published research on the ability of consumers to utilise information about the alcohol content of beverages when expressed in different forms, for example in standard drinks or units versus percentage alcohol content.

DESIGN AND METHODS

A review of the literature on standard drink definitions and consumer understanding of these, actual drink pouring, use of standard drinks in guidelines and consumer understanding and use of these.

RESULTS

Standard drink definitions vary across countries and typically contain less alcohol than actual drinks. Drinkers have difficulty defining and pouring standard drinks with over-pouring being the norm such that intake volume is typically underestimated. Drinkers have difficulty using percentage alcohol by volume and pour size information in calculating intake but can effectively utilise standard drink labelling to track intake. Standard drink labelling is an effective but little used strategy for enabling drinkers to track their alcohol intake and potentially conform to safe or low-risk drinking guidelines.

Labelling alcoholic drinks: percentage proof, original gravity, percentage alcohol or standard drinks?

Drivers who wish to stay 'under the limit', problem drinkers wishing to control their drinking and literally anyone who drinks alcohol and is concerned about their health are all increasingly exhorted to monitor their alcohol intake by counting 'standard drinks' (each containing 8-14 g, depending on the country in question). Unfortunately, the evidence presented in this paper suggests that this system permits many errors. In particular, it requires two assumptions to be met: (1) that drinks of the same beverage type (i.e. beer, wine, fortified wine or spirits) normally contain the same percentage of alcohol by volume; and (2) that people serve, or are served, alcoholic drinks in standard serves. It is shown that in practice the strength of drinks available for sale of a given beverage type varies widely and that 'atypical' strengths form a significant proportion of alcohol sales. Furthermore, whether drinking occurs in a private residence or on licensed premises, it is usual for quantities greater than the supposed Australian standard of 10 g to be served. In practice, most people are unaware of the strengths of different beverages or the rough equivalences between them. Even if they are taught the standard drink system, they cannot make allowances for 'atypical' variations in strength. It is suggested these problems could be readily overcome if all alcohol containers were labelled in terms of standard drinks. The benefits of such a labelling system are discussed with regard to health promotion, accident prevention and the accuracy of surveys of alcohol use.

Alcohol, cardiovascular diseases and all causes of death: a review of the epidemiological evidence

This paper reviews the epidemiological evidence on the association of alcohol consumption with the major cardiovascular diseases (hypertension, stroke and coronary heart disease), and all causes of death. The focus is on light and moderate consumption and several important methodological issues are apparent with the epidemiological evidence on alcohol and mortality. The epidemiological data justify the following recommendations on alcohol consumption. The evidence does not support the unqualified claim that light and moderate drinking confers overall health benefits. However, in persons over 35 years of age, there is no consistent evidence that daily consumption of up to 2-3 drinks in men or up to 1-2 drinks in women increases the risk of dying. Non-drinkers should not be encouraged to change their drinking status. The consumption of more than 2-3 drinks per day in men and more than 1-2 drinks per day in women should be actively discouraged. Further research on the effects of light and moderate alcohol consumption on cardiovascular disease and all causes of death are required, particularly in young people, women and the elderly.

A drink is a drink? Variation in the amount of alcohol contained in beer, wine and spirits drinks in a US methodological sample

BACKGROUND

Empirically based estimates of the mean alcohol content of beer, wine and spirits drinks from a national sample of US drinkers are not currently available.

METHODS

A sample of 310 drinkers from the 2000 National Alcohol Survey were re-contacted to participate in a telephone survey with specific questions about the drinks they consume. Subjects were instructed to prepare their usual drink of each beverage at home and to measure each alcoholic beverage and other ingredients with a provided beaker. Information on the brand or type of each beverage was used to specify the percentage of alcohol.

RESULTS

The weighted mean alcohol content of respondents' drinks was 0.67 ounces overall, 0.56 ounces for beer, 0.66 ounces for wine and 0.89 ounces for spirits. Spirits and wine drink contents were particularly variable with many high-alcohol drinks observed.

CONCLUSIONS

While the 0.6-ounce of alcohol drink standard appears to be a reasonable single standard, it cannot capture the substantial variation evident in this sample and it underestimates average wine and spirits ethanol content. Direct measurement or beverage-specific mean ethanol content estimates would improve the precision of survey alcohol assessment.

Shape of glass and amount of alcohol poured: comparative study of effect of practice and concentration

OBJECTIVE

To determine whether people pour different amounts into short, wide glasses than into tall, slender ones.

DESIGN

College students practised pouring alcohol into a standard glass before pouring into larger glasses; bartenders poured alcohol for four mixed drinks either with no instructions or after being told to take their time.

SETTING

University town and large city, United States.

PARTICIPANTS

198 college students and 86 bartenders.

MAIN OUTCOME MEASURES

Volume of alcohol poured into short, wide and tall, slender glasses.

RESULTS

Aiming to pour a "shot" of alcohol (1.5 ounces, 44.3 ml), both students and bartenders poured more into short, wide glasses than into tall slender glasses (46.1 ml v 44.7 ml and 54.6 ml v 46.4 ml, respectively). Practice reduced the tendency to overpour, but not for short, wide glasses. Despite an average of six years of experience, bartenders poured 20.5% more into short, wide glasses than tall, slender ones; paying careful attention reduced but did not eliminate the effect.

CONCLUSIONS

To avoid overpouring, use tall, narrow glasses or ones on which the alcohol level is premarked. To avoid underestimating the amount of alcohol consumed, studies using self reports of standard drinks should ask about the shape of the glass.

Low-risk drinking guidelines: the scientific evidence

In 1997 the Addiction Research Foundation of Ontario and Canadian Centre on Substance Abuse released updated guidelines for low-risk alcohol consumption. This paper presents the scientific rationale behind this statement. Important comprehensive overviews on the consequences of alcohol use were studied. Formal meta-analyses on morbidity and mortality were examined wherever possible. Individual elements from similar guidelines were investigated for their scientific foundation. Limited original analyses defined risk levels by average weekly consumption. The evidence reviewed demonstrated that placing limits on both daily intake and cumulative intake over the typical week is justifiable for the prevention of important causes of morbidity and mortality. Gender-specific limits on weekly consumption were also indicated. In these updated guidelines intended for primary prevention, days of abstinence are not necessarily recommended. Intoxication should be avoided and abstinence is sometimes advisable. Available evidence does not strongly favour one alcoholic beverage over another for cardiovascular health benefits.

Low-risk drinking guidelines: the scientific evidence

In 1997 the Addiction Research Foundation of Ontario and Canadian Centre on Substance Abuse released updated guidelines for low-risk alcohol consumption. This paper presents the scientific rationale behind this statement. Important comprehensive overviews on the consequences of alcohol use were studied. Formal meta-analyses on morbidity and mortality were examined wherever possible. Individual elements from similar guidelines were investigated for their scientific foundation. Limited original analyses defined risk levels by average weekly consumption. The evidence reviewed demonstrated that placing limits on both daily intake and cumulative intake over the typical week is justifiable for the prevention of important causes of morbidity and mortality. Gender-specific limits on weekly consumption were also indicated. In these updated guidelines intended for primary prevention, days of abstinence are not necessarily recommended. Intoxication should be avoided and abstinence is sometimes advisable. Available evidence does not strongly favour one alcoholic beverage over another for cardiovascular health benefits.

The use of an alcometer in clinical forensic practice

Forensic physicians are at times required to provide a professional opinion on a person's degree of intoxication through alcohol, particularly with regard to fitness for interview by the police. Inherent to these assessments is an estimation of the blood alcohol concentration (BAC). Most forensic physicians rely on taking a history regarding recent alcohol consumption and a clinical assessment to estimate the BAC. We report a study in which the BAC of 118 detainees was estimated and compared with the BAC measured by an alcometer. Our estimations were accurate in 66% of cases. Most errors resulted from underestimating the BAC. Additionally, we attempted to determine fitness for interview using a single measurement of the BAC without a clinical assessment. 19% of those who were assessed as unfit for interview had a BAC of less than the UK legal limit for driving (currently 80 mg%) and 37% considered fit, had a BAC above that level. We conclude that the routine use of alcometers would enhance the practice of forensic medicine but could not replace its role in the assessment of levels of alcohol intoxication.

The alcohol content of self-report and 'standard' drinks

A stubborn problem in alcohol epidemiology is that of standardization of unit of measurement. Consistent use of the 'standard drink' in research reports is hampered by difficulties in the assessment of the alcohol content of, particularly, self-reported drinks. Alcohol content of a drink depends on strength of the beverage and volume of the glass or container from which the beverage is taken. Both factors vary considerably between times, regions and individuals. Interview protocols and questionnaires rarely take into account the fact that people consume alcoholic beverages from a large variety of glasses and containers. In the present study the common presumption is tested of equality of alcohol content of standard and self-reported drinks. The test consisted of measuring the amount of wine, fortified wine and spirits people usually pour in the glass typical for the beverage type. The sample was drawn from the general Dutch population in 1985. The results show that on average self-reported drinks taken at home contained more than the presumed standard (10 g per drink). The deviation was highest for spirits (+26%), followed by fortified wines (+14%) and least for wine (+4%). There seemed to be a positive relationship between deviation from 'standard' and strength of the alcoholic beverage. This result is in line with data on the coverage of sales data: aggregate, survey-based spirits consumption shows the lowest coverage of sales. The effect of the difference between actual and presumed content of drinks on estimates of consumption is an overall increase of 7.5%, higher for women (+12%) than for men (+6%). Results are discussed with respect to the use of the concept of 'standard unit' in research protocols and health education campaigns.

Influencing the labelling of alcoholic beverage containers: informing the public

In 1990, a small research project costing about Aus. $4500 conducted in a Perth shopping centre directly influenced the development of a national policy within 4 months of its completion. The policy in question is a recommendation by Australia's Ministerial Council on Drug Strategy that all alcoholic beverage containers should carry labels indicating the number of 'standard drinks' they contain. The purpose of this paper is to describe the events leading up to so unusual an event with a view to discerning what factors may have been critical for its occurrence. The paper attempts to analyse the nature of the interactions between the research team and the policy makers. It is argued that the critical factors included there being a favourable policy climate created by the National Campaign Against Drug Abuse, the support of influential public servants and, in turn, politicians, the consultative process which lead to the study's design and the manner in which the findings were disseminated.

Male alcohol consumption and fecundity in couples attending an infertility clinic

The relationship between male alcohol intake and fertility was studied for 258 couples attending an infertility clinic. 21% consumed less than 1 unit per week on average, 10% consumed between 1 and 5 units per week, 23% consumed between 6 and 10 units per week, 27% consumed 11 to 20 units per week and 19% consumed more than 20 units per week. There was no significant association between alcohol consumption and any semen parameter. 110 men had a female partner who was apparently normal. There was no significant difference in the alcohol intake between the 'normal' and 'abnormal' female groups. Couples were followed-up for up to 32 months. Sixteen women had a treatment independent conception within the 'normal' female group. There was no significant association between the amount of alcohol consumed per week and the fertility outcome.

The effect of 'standard drink' labelling on the ability of drinkers to pour a 'standard drink'

Australia's National Health Policy on Alcohol has recommended that beverage containers be labelled so that alcohol content is 'readily understandable by the public'. Health promotion to increase the responsible use of alcohol now relies extensively on the concept of a standard drink--usually defined as 10 g of ethyl alcohol. Numerous difficulties confront a drinker who wishes to apply the standard drink system to monitor alcohol intake. This report describes a series of experimental tests of the proposal that these difficulties are minimised if alcohol containers have their alcohol content indicated in terms of standard drinks in addition to the usual percentage alcohol by volume method. Subjects were drinkers recruited from a Perth shopping mall and were tested only on beverage types they had consumed within the previous week. They were required to pour what they judged to be a single standard drink from a 750 ml bottle of either wine or beer. Beer drinkers achieved greater accuracy in this task when the bottles had standard drink labels, even when the glass size and beverage strength were varied. Wine drinkers had equal difficulty with this task whether standard drink or percentage labels were used. The addition of a 'ladder' up the side of a wine bottle with graduations in standard drinks would be necessary for wine drinkers to achieve a high level of accuracy. We conclude that labelling drink containers with their alcohol content in terms of standard drinks would better equip all drinkers to follow the advice of health educators.