The metabolism of alcohol: on the validity of the Widmark equations, in obesity and in racial and ethnic groups

Access schedules mediate the impact of high fat diet on ethanol intake and insulin and glucose function in mice

Alcoholism and high fat diet (HFD)-induced obesity individually promote insulin resistance and glucose intolerance in clinical populations, increasing risk for metabolic diseases. HFD can also stimulate alcohol intake in short-term clinical studies. Unfortunately, there is currently a disconnect between animal models and the clinical findings, as animal studies typically show that HFD decreases ethanol intake while ethanol intake mitigates HFD-induced effects on insulin and glucose dysfunction. However, most previous animal studies utilized forced or continuous HFD and/or ethanol. In three experiments we sought to determine whether HFD (HFD = 60% calories from fat) vs. control diet (chow = 16% fat) alters voluntary two-bottle choice ethanol intake in male C57Bl/6J mice given differing access schedules for 6-7 weeks, and we assessed the resultant impact on metabolic function via insulin and glucose tolerance tests. Experiment 1: Unlimited Access Ethanol + HFD (UAE + HFD; n = 15; 10% ethanol v/v, ad libitum diet and ethanol) or UAE + Chow (n = 15). Experiment 2: Limited Access Ethanol + HFD (LAE + HFD; n = 15; ethanol = 4 h/day; 3 days/week, ad libitum diet) or LAE + Chow (n = 15) with increasing ethanol concentrations (10%, 15%, 20%). Experiment 3: Intermittent HFD with limited access to ethanol (iHFD-E; HFD = single 24-h session/week; ethanol = 4 h/day; 4 days/week) (n = 10). UAE + HFD mice consumed significantly less ethanol and were insulin-resistant and hyperglycemic compared with UAE + Chow mice. LAE + HFD mice consumed ethanol similarly to LAE + Chow mice, but exhibited hyperglycemia, insulin resistance, and glucose intolerance. iHFD-E mice displayed binge eating-like behaviors and consumed significantly more ethanol than mice given ad libitum chow or HFD. iHFD-E mice did not have significantly altered body composition, but developed insulin insensitivity and glucose intolerance. These findings suggest that access schedules influence HFD effects on ethanol consumption and resultant metabolic dysfunction, ethanol intake does not improve HFD-induced metabolic dysfunction, and binge eating-like behaviors can transfer to binge drinking behaviors.

The influence of nocturnal alcohol ingestion on snoring

Nocturnal alcohol ingestion is known to increase obstructive sleep apnea. It is assumed that snoring also increases under the influence of alcohol although only few data are available to support this hypothesis. The aim of this study was to investigate the influence of nocturnal alcohol ingestion on the properties of snoring. Twenty healthy male reported non-snorers (n = 10) and snorers (n = 10) underwent night-time polysomnography at three randomly assigned nights with a blood alcohol concentration (BAC) of 0.0, 0.5 and 0.8 per thousand, respectively. Snoring events were recorded by a room and body contact microphone simultaneously. Loudness and incidence of snoring were calculated and correlated to the total sleep time (TST), body position and sleep stages. Snorers revealed an increase of the apnea-hypopnea-index (AHI) under increasing BAC, whereas no decrease in the nocturnal SAO(2) was detected. Non-snorers had no increase in the AHI but a decrease in SAO(2). Snoring individuals revealed a dose-dependent increase of incidence (TSI) and loudness (LSI) of snoring with regard to the TST. The TSI increased by a factor of 1.6 at 0.5 per thousand BAC and by 4.2 at 0.8 per thousand BAC compared to the 0.0 per thousand- BAC-night. The LSI increased threefold at 0.5 per thousand BAC and 14-fold at 0.8 per thousand BAC. Snoring increased to a bigger extent in a supine position compared to non supine and during REM stage as well as Non REM 3/4 stage. Non-snorers did not present any effect of alcohol on the snoring properties with regard to TST, body position and sleep stage. The results indicate that nocturnal alcohol ingestion affects individuals with a reported history of snoring to a greater extent than non-snorers. Non-snorers did not turn into snorers under increasing alcohol influence. The recommendation, to avoid alcohol intake prior to sleep, gains of special clinical importance for individuals already snoring.

The intoxication power of alcoholic beverages: image and reality

Because of the newness of wine coolers and their youthful appeal, questions have arisen of whether consumers have a realistic understanding of coolers' intoxication power. Questionnaires were given to 459 undergraduates to determine how accurately they could estimate the number of drinks (beer, light beer, wine, wine coolers, and whiskey) they would have to consume to become legally intoxicated. Results indicate that, although responses differ by race and gender, respondents have a poor understanding of the intoxication power of alcohol in general and of hard liquor and wine coolers in particular. Whereas liquor's intoxication power was overestimated, the intoxication power of wine coolers was underestimated relative to other types of drinks by the total sample and underestimated in absolute terms by females.

Interindividual variations in the disposition and metabolism of ethanol in healthy men

Forty-eight healthy men each drank a dose of ethanol, 0.68 g/kg of body weight, as neat whisky at about 09.00, after fasting overnight. The drink was finished within 20 min and the concentrations of ethanol in samples of capillary blood were determined at 30-60 min intervals for 7 hr. Rectilinear regression lines were fitted to the elimination phase of blood concentration time profiles and blood-ethanol parameters were calculated as described by Widmark. In 23, 14, 8 and 3 subjects the peak blood ethanol concentrations were reached at 30, 60, 90 and 120 min timed from starting to drink. The highest concentration of ethanol in blood was 0.92 +/- 0.022 mg/ml (mean +/- SE) and the coefficient of variation (CV) was 16.8%. The blood concentration of ethanol extrapolated to zero-time was 0.98 +/- 0.009 mg/ml (CV = 6.5%) and the apparent volume of distribution (Vd) was 0.695 +/- 0.0064 L/kg (CV = 6.4%). The rate of ethanol elimination from blood was 0.126 +/- 0.0018 mg/ml/hr (CV = 9.9%) and the body clearance was 87.5 +/- 1.1 mg/kg/hr (CV = 8.7%). The apparent volume of distribution of ethanol was inversely related to the subject's body weight (r = -0.59 +/- 0.118, p less than 0.001). The elimination rate from blood was lower in those subjects with larger distribution volume; the parameters were negatively correlated (r = -0.52 +/- 0.126, p less than 0.001). The results show that blood-ethanol parameters calculated according to Widmark's method have low intersubject variability when the dose of ethanol administered and the condition of the test subjects are carefully controlled.(ABSTRACT TRUNCATED AT 250 WORDS)

Pharmacokinetics of ethanol: a review

The pharmacokinetics of ethanol in man are reviewed from a historical perspective from the earliest attempts at kinetic analysis of urinary data in 1899 to the present nonlinear analysis of blood alcohol concentration (BAC) and time data. Review of the various kinetic theories that have been utilized to describe the kinetics of alcohol metabolism is provided. Extensive review is made of recent investigations supporting the application of Michaelis-Menten enzyme kinetics to describe alcohol metabolism. Results of direct, nonlinear least-squares computer fitting of BAC following intravenous and oral feeding of alcohol both in the fasting and fed states are presented with appropriate theory. The kinetics of the oral absorption of alcohol and the relationship among stomach emptying rate, the apparent absorption rate, and the area under the BAC-time curve are discussed and data presented. The kinetics of multiple Michaelis-Menten pathways are discussed with application to the (potential) contributions of the MEOS and/or ADH systems to the observed BAC curve and resultant kinetic parameters. Several methods of obtaining pharmacokinetic (Michaelis-Menten) parameters from BAC curves and their interpretation and usage in comparative studies are presented.