Results of a study in which longitudinal data on alcohol consumption across the life course of individuals was analysed have shown that frequent drinking increases in mid- to older- age, particularly among men. The study, from a research team based in various institutions in England and Scotland, is published today in the journal BMC Medicine.



This is the first attempt to synthesise longitudinal data on alcohol consumption from several overlapping cohorts in order to obtain information on how drinking frequency changes over a lifetime. Most studies on alcohol consumption pattern take a ‘snapshot’ at a single moment in time by drawing data from cross-sectional population surveys. In the UK, for example, these would include the General Lifestyle Survey, the Health Survey for England and the Scottish Health Survey. While useful in identifying high risk groups and allowing comparison of different age groups, these types of studies cannot gauge how consumption changes in an individual over time. Lead author on the current study, Dr. Annie Britton, from University College London said "Understanding how drinking behaviour fluctuates throughout life is important to identify high risk groups and trends over time. Research on the health consequences of alcohol needs to incorporate changes in drinking behaviour over the life course. The current evidence base lacks this consideration. Failure to include such dynamics in alcohol is likely to lead to incorrect risk estimates."



To try to address this issue, the research team on the current study took data from nine UK-based prospective cohorts in which at least three repeated alcohol consumption measures were taken from individuals. The combined sample size achieved from this approach was 59,397, and included 174,666 alcohol observations, with the data spanning from adolescence to very old age (90 years plus). The researchers harmonised the data from the different cohorts and used statistical modelling to determine how drinking frequency changed with age in both men and women.



The results of the study indicated that, for men, mean alcohol consumption rose sharply during adolescence, peaking at about 20 units per week at around 25 years of age. Consumption then declined, reaching a plateau in middle age and then declining from around 60 years to 5-10 units, the equivalent of 3-5 pints of beer per week. A similar pattern was observed for women, although overall consumption was less. However, frequent drinking, that is daily or on most days of the week, became more common in mid-to older-age, particularly in men. More than 50% of men in this bracket reported frequent drinking.



The results of this study are relevant to design of public health initiatives and interventions, as doctors in the UK and elsewhere are increasingly seeing cases of alcohol misuse among elderly people. Dr Britton concluded: "We have shown that people change the way they consume alcohol as they age, and as such, studies reliant on a single measure of alcohol intake are likely to be biased. It is essential that the dynamic nature of exposure to alcohol over the life span is incorporated into the estimates of harm."