None listed
Conditions
Brief summary
Alcohol consumption by Australian women, especially younger women, has been steadily increasing together with the prevalence of episodic or binge drinking by such subjects. The increase in alcohol intake has been occurring in the setting of an increased public health recognition that the regular consumption of 1-2 standard alcoholic drinks per day may confer protection against coronary artery disease. However, the balance of potential risks and benefits for alcohol consumption have, more often than not, been generated on the basis of data from studies in men. This is especially true with respect to the effects of alcohol on blood pressure and hypertension. There is continuing controversy with respect to the amount of alcohol which will influence blood pressure in women and uncertainty as to the direction of any effect. Population-based epidemiological studies suggest that low level alcohol consumption (4-7 drinks per week) may lower blood pressure in women while higher levels of consumption (2 or more drinks per day) have been associated with higher levels of blood pressure. The present proposal will directly test these assumptions by measuring BP over 24 hr on a carefully controlled basis in women who are drinking at these levels over 4-week periods. The results will be compared to levels of BP measured after 4 weeks of abstinence from all alcohol.
Interventions
During an initial 4-week run-in period, subjects continue their usual regular intake. They are then randomized into a 3 period cross-over study of Latin square design, during which they consume during sequential 4 week study periods:-
(1) 140-210 g/week (2-3 standard drinks/day) of alcohol as red wine (a shiraz cabernet blend of known composition and alcohol content - alcohol 13% v/v, sourced from Orlando Wyndham, Rowland Flat, South Australia) (approx. 2-3 bottles per week with a minimum cons
During an initial 4-week run-in period, subjects continue their usual regular intake. They are then randomized into a 3 period cross-over study of Latin square design, during which they consume during sequential 4 week study periods:- (1) 140-210 g/week (2-3 standard drinks/day) of alcohol as red wine (a shiraz cabernet blend of known composition and alcohol content - alcohol 13% v/v, sourced from Orlando Wyndham, Rowland Flat, South Australia) (approx. 2-3 bottles per week with a minimum consumption of 20 g per day every day and maximum consumption of 30 g per day every day), or (2) 30-70 g/week of alcohol as the same red wine (approx. 0.5 to 1 bottle per week with a minimum consumption of 10 g per day on 3 of the 7 days and maximum consumption of 10 g per day every day), or (3) as a control, an identical red wine but which was de-alcoholised (again sourced from Orlando Wyndham, Rowland Flat, South Australia) (approx. 2-3 bottles per week with equivalent volumes consumed daily matched to the high-alcohol period). During this 4-week period they otherwise remain abstinent from all alcohol. There was no washout period between each 4-week study period. The precise amount of red wine and de-alcoholised red wine within the above ranges is dictated by each subject's usual alcohol intake at entry to the study. Entry to each intervention phase of the study is scheduled so that measurement of blood pressure and lipid levels correspond as closely as possible to the early follicular phase of each subject's menstrual cycle. This is to minimize any confounding from differences in hormone levels within and between subjects resulting from phase of the menstrual cycle. All measurements are performed at the end of the 4-week run-in period and each of the three 4-week study periods. Compliance with the designated changes in alcohol intake are recorded by 7-day retrospective weekly diaries, completed at weekly visits to the clinical trials unit. In addition serum is sampled at the end of the 4-week run-in period and the end of each subsequent study period for both gamma-glutamyl transpeptidase and carbohydrate deficient transferrin as biomarkers of alcohol intake. Twenty-four hour urinary 4-Omethylgallic acid is determined as a biomarker of red wine intake.
Sponsors
University of Western Australia
Study design
Allocation
Randomised controlled trial
Intervention model
Crossover
Primary purpose
Prevention
Masking
Open (masking not used)
Eligibility
Sex/Gender
All
Age
20 Years to 45 Years
Healthy volunteers
Yes
Inclusion criteria
Women 20-45 years of age, pre-menopausal and regularly drinking in the range of 140 to 210 g/wk ethanol (equivalent to approximately 14 and 21 standard drinks). BMI will be < 30 kg/m2 and subjects will be non-smokers. They will be otherwise healthy, free of clinical evidence of vascular disease on examination.
Exclusion criteria
Past history of hypertension, dyslipidaemia, diabetes mellitus or liver disease. Past history of coronary disease, cerebrovascular disease or peripheral vascular disease. Any regular medication, including aspirin, non-steroidal anti-inflammatory drugs or the oral contraceptive pill.
Outcome results
None listed