Patterns of alcohol use and multiple risk behaviour by gender during early and late adolescence: the ALSPAC cohort

Introduction

Modifiable risk behaviours such as smoking, alcohol intake, drug use, poor diet and physical inactivity, both individually and collectively, account for substantial morbidity and mortality throughout life.^1–4 Critically, risk behaviours are often initiated during adolescence^5,6 and the frequency of engagement in behaviours rises with increasing age during the teenage years,^6–9 often continuing into early adulthood.^10–14 A number of studies have demonstrated clustering of risk behaviours such as smoking, substance use, antisocial behaviour and sexual risk behaviour during adolescence,^15–21 and estimates from the USA, Canada and the UK indicate that between 6 and 13% of adolescents smoke regularly, drink alcohol and use illicit drugs.^8,9,22,23 Moreover, early initiation of risk behaviours is associated with engagement in multiple risk behaviours during both early and late adolescence,^5,24,25 and simultaneous engagement in such behaviours during adolescence is associated with increased morbidity and premature mortality.²⁶

Regular alcohol use and binge drinking among adolescents are risk behaviours of particular concern. Early use of alcohol is associated with multiple risk behaviours and detrimental impacts including sexual risk behaviour, sexually transmitted infections, substance use, criminal and violent behaviour, academic underachievement, mood disorders, injury and high levels of alcohol-related attendances at hospital.^13,27–35 Survey data also demonstrate that ∼70% of young people in the UK consume alcohol and the prevalence of recent use is over 3-fold higher than recent tobacco or cannabis use. The UK has one of the highest levels of alcohol use in young people among European countries, ranking third of 35 countries in estimated alcohol consumption and prevalence of recently being drunk.³⁶

Following upward trends in alcohol use in the UK during the 1990s and early 2000s,^37–40 data indicate that self-reported alcohol consumption and heavy drinking have fallen slightly among men and women across all age groups in recent years, including adolescents.^8,9,41 However, alcohol-related hospital admissions have continued to rise,³⁸ rates of alcohol-related deaths in the UK have increased consistently over recent decades,^37,42,43 and mean alcohol consumption among adolescents has risen steadily over recent years. In addition, reported alcohol consumption has increased in adolescent boys aged 11–13 years.^8,44,45

It is not yet clear whether such trends will continue to be sustained, and the impacts of high levels of use in adolescence, and changing patterns of consumption by gender or socio-demographic group, have yet to be fully clarified. Patterns of alcohol use vary between genders both in the UK and internationally,^46,47 but increases in alcohol consumption particularly among young females in the UK^37,40 have narrowed the gender gap in alcohol intake and binge drinking in young people. Among adolescents, gender-related patterns of alcohol consumption have been reported in relation to use during early adolescence or the type of drink consumed, but gender differences for a number of other measures such as mean alcohol consumption or frequency of recent use are less clear.^8,9,31,48,49

Given evidence demonstrating an association between alcohol use and multiple risk behaviours, it is possible that the pattern of engagement in a range of risk behaviours varies by gender at this time. This may have implications for the design and implementation of public health interventions to address single and multiple risk behaviours as well as interventions to address the resulting burden of disease. Whilst studies have demonstrated that engagement in multiple risk behaviours differs by gender during adolescence,^5,6,16 the majority of studies focus on a relatively narrow range of behaviours,^{6,15,16,19,23,50} and findings vary by age at measurement and the individual risk behaviours considered.

This paper aims to summarize and compare data from a prospective UK birth cohort [the Avon Longitudinal Study of Parents and Children (ALSPAC)] describing the prevalence and pattern of alcohol use and binge drinking by gender during early and later adolescence, alongside analysis of the prevalence of multiple risk behaviour by gender at age 15–16 years. Detailed analyses of data relating to the prevalence and determinants of alcohol use within the ALSPAC cohort at age 10 and 13 years have been previously reported and are included in the current analysis based on categorizations used in the original publications.^48,49,51

Methods

The core sample of the ALSPAC includes 14 541 women who were expecting to deliver infants between 1 April 1991 and 31 December 1992 in the former county of Avon, UK. ALSPAC parents and children have been followed-up regularly since recruitment, via data from questionnaires completed by mothers, children and teachers and via clinic assessments. The population included is representative of a primarily white population with a small proportion of individuals in ethnic minority groups (5%) and diverse socio-economic backgrounds. Ethical approval for the study was granted from the ALSPAC Law and Ethics Committee and the local research ethics committee. Full details about the ALSPAC study and design are described elsewhere (http://www.bristol.ac.uk/alspac).

Results

Discussion

The prevalence of alcohol use among adolescents was low overall at age 10 years, but at 13 years of age, over half of boys and girls had consumed alcohol and one-fifth had engaged in binge drinking. By age 15 years, nearly half of adolescents had engaged in binge drinking and a third engaged in hazardous drinking at age 16 years with no clear difference in the prevalence by gender.

In contrast to binge drinking and hazardous drinking, the prevalence of engagement in a wide range of risk behaviours varied between boys and girls at 15–16 years of age, with antisocial and criminal behaviours, cannabis use and vehicle-related risk behaviours being more prevalent among boys but tobacco smoking, self-harm and physical inactivity being more prevalent among girls. A greater proportion of girls also reported engaging in sex before the age of 16 and having unprotected sex compared with boys. Whilst the prevalence of individual behaviours differed between boys and girls, there was no evidence of a difference in the median number of behaviours between boys and girls. Engagement in the majority of the risk behaviours (particularly substance use and sexual risk behaviour) was associated with alcohol use at 15 and 16 years of age.

The high levels of binge drinking and hazardous alcohol drinking at age 15–16 years are cause for concern. Recent guidance from the Chief Medical Officer recommends that young people do not drink alcohol at all before the age of 15 and that between 15 and 17 years of age, they should drink alcohol on no more than 1 day per week, and should not exceed recommended adult daily limits.⁴⁴ The data that we and others report⁵¹ indicate that although advice is clear, there is disparity between the recommended limits and young people's behaviour, with substantial proportions of adolescents engaging in risk behaviours at greater than recommended levels that might be harmful to health.

Drinking outside of guideline levels at 15–16 years of age has been associated with greater experience of alcohol-associated risk behaviours such as forgetfulness, alcohol-related violence and regretted or unprotected sex,³¹ and high intake has also been associated with increased likelihood of injury, sexually transmitted infections, crime, motor vehicle collisions, car crash fatality and suicide.^{4,13,27,32–34} Our data also indicate that a higher level of alcohol use at 15 years of age is associated with engagement in a number of risk behaviours at 15–16 years of age, as supported by previous studies,^{16,22,29,34,53} although the cross-sectional nature of this analysis precludes any causal inference. The lack of association between alcohol consumption and physical inactivity is comparatively less well studied and warrants further research.

The high prevalence of initiation of alcohol consumption by 13 years of age (52% boys; 54% girls), alongside reports of rising consumption among very young adolescents in the UK⁴⁵ also presents challenges for public health. Early alcohol use has been associated with greater risk of heavy drinking and dependence in adulthood,^12,31,52 whilst binge drinking during adolescence is also associated with a 2- to 3-fold increased risk of binge drinking in adulthood.⁵⁴ Notwithstanding damage to the liver associated with consistent high levels of alcohol consumption,⁵⁵ these findings indicate that the burden of hazardous drinking and dependence may rise among young adults in coming years, concurrent with the burden of behaviours associated with alcohol use, such as unprotected sex and aggressive behaviour.

Currently, the burden of alcohol use and dependence is greater among male adolescents (boys, 7.2%; girls, <2.1%)³ and adults,^56–58 but it is possible that the alcohol-associated health burden among females will become comparatively more evident in the coming years owing to increases in consumption and binge drinking particularly among young females over recent decades.^8,37,40,59 Furthermore, evidence demonstrates that the brain continues to undergo structural and functional changes during adolescence, suggesting that alcohol consumption at this stage in the life course may have important consequences for brain development, whilst the identification of differences between genders in the trajectories of brain development^60–62 raises the possibility that alcohol-related impacts on cognitive developments may differ between males and females.^60,63

The reasons for changing patterns of alcohol use between genders are complex and are variable across cultures internationally suggesting that biological and socio-cultural influences such as gender equality, gender–income equity and changes in working patterns might play a role.^47,64–66 Gender-dependent variation in factors such as abstention from alcohol use, the type of drink consumed, pace of intake or engagement in alcohol-related risk behaviours may influence subsequent impacts to health^8,31,67,68 and such patterns and trends will need to be monitored over the longer term.

In contrast to the similar prevalence of alcohol use and binge drinking among adolescents aged 13 and 15–16 years, we found that engagement in a range of other risk behaviours differed by gender at age 15–16 years and those behaviours more associated with violence and possible injury, such as assault, criminal damage and carrying a weapon, were markedly more prevalent among boys compared with girls. These findings indicate that among boys, there may be a greater propensity for ‘sensation seeking’ or more immediate gratification, although the possibility that there may also be a greater likelihood of reporting of such behaviours among boys cannot be ruled out.

Impulsivity and sensation seeking have been associated with greater likelihood of gambling onset in youth, risky sexual behaviour, smoking, alcohol use and aggression,^69–72 and a number of studies also report clustering of ‘delinquent’ or antisocial behaviour with smoking, alcohol and drug use, crime and risky sexual behaviour during adolescence,^10,16,19 all of which may individually and collectively cause harm to health. Nevertheless, studies show that violence, assault and antisocial behaviour peak at around 15 years in the UK and decline during early adulthood,⁷³ and the long-term impacts of the high prevalence of engagement in such behaviours and differences between genders are not yet clear within this cohort.

Interestingly, we also identified that behaviours with less immediate adverse impacts on health including tobacco smoking, self-harm and physical inactivity were more prevalent among girls compared with boys; a finding supported by national survey data.^8,74,75 Prevalence estimates for physical inactivity and smoking were similar to nationally reported rates, although the prevalence of ever having self-harmed among girls (25%) was higher compared with reported estimates.⁷⁴ The greater engagement in behaviours with longer term impacts on health among girls may reflect different underlying psychological motivations and/or coping mechanisms by gender during adolescence and further research is needed to better understand risk and protective factors for engagement in different types and clusters of behaviours by gender.

The high prevalence of physical inactivity (74%) indicates that this is a norm during adolescence and thus it could be argued that this should not be considered a risk behaviour. However, guidance from the Chief Medical Officer recommends that young people undertake at least 60 min per day of at least moderate physical activity every day, and higher impact exercise at least twice a week to reduce the risk of harm to health.⁷⁶ In our study, the data indicate that the majority of female adolescents and two thirds of male adolescents were not undertaking the minimum recommended amount of physical exercise, which increases the risk of chronic disease later in life.⁷⁶ England-wide survey also demonstrate that physical inactivity decreases up to age 15 years among girls but remains more consistent among boys, exacerbating gender differences at ages 14 and 15 years.⁷⁵ Historically, levels of physical inactivity have also been lower among younger female adults (age 16–24 years) compared with males.⁷⁶

Our data demonstrate that the prevalence of risk behaviours such as unsafe sex and illicit drug use are comparatively low among all of the behaviours examined, yet neither the harms associated with such behaviours, nor the clustering of such behaviours, should be overlooked. Global burden of disease studies estimate that risk behaviours such as unsafe sex, self-inflicted injuries and illicit drug use are key risk factors for incident disability-adjusted life years (DALYs), contributing between 2 and 4% to DALYs among 10–24 year olds globally,³ and the burden of disease, mortality and social impacts associated with clustered behaviours is likely to be markedly higher.

Limitations

Whilst the use of a birth cohort has multiple advantages for analysis of the determinants and impacts of a wide range of exposures over an extended time period in a large sample, there are limitations to these analyses which must be noted. The analysis of simultaneous engagement in a large number of behaviours reduces the sample size owing to missing data, and the ALSPAC cohort is subject to loss to follow-up at each stage. Male cohort members and those from lower socio-economic groups are also less likely to attend assessment interviews,⁴⁸ which could lead to inaccurate prevalence estimates, and self-report measures of behaviour used in this study are subject to reporting bias. Nevertheless, cohort members are given clear assurance of anonymity and confidentiality, and the prevalence estimates of behaviours including ever having consumed an alcoholic drink at or by age 13 years, and physical inactivity at age 15–16 years, were similar to nationally reported rates.^8,75 Since cut-off points for determining measures of behaviour associated with harm to health are unclear during adolescence for certain behaviours, it is also possible that different thresholds may be appropriate at different stages of adolescence.

Implications and conclusions

Taken together, the data presented in this paper highlight high prevalence of alcohol use by 15 years of age with little evidence of a difference by gender. The data also demonstrate high prevalence of physical inactivity, criminal offending and antisocial behaviour and hazardous drinking by 16 years of age, as well as differences between boys and girls in relation to engagement in particular behaviours, but not the number of different behaviours per se.

These findings have implications for policy and practice. First, effective communication of clear harm reduction messages is required to address the high prevalence of hazardous drinking and physical inactivity during adolescence. Health policies and harm reduction messages also need to account for engagement in a wide spectrum of risk behaviours during adolescence which may vary by gender and socio-demographic determinants. Further research is needed to examine the clustering of multiple behaviours, the influence of gender and the social patterning and determinants of engagement in single and multiple risk behaviours to provide insight into effective strategies by which to address risk behaviour and thus to reduce harms to health.

Supplementary data

Supplementary data are available at the Journal of Public Health online.

Funding

Research reported here was supported by the Economic and Social Research Council (grant RES-060-23-0011; R.M. and G.L.); the Centre for the Development and Evaluation of Complex Interventions for Public Health Improvement (DECIPHer) which receives funding from the British Heart Foundation, Cancer Research UK, Economic and Social Research Council (RES-590-28-0005), Medical Research Council, the Welsh Assembly Government and the Wellcome Trust (WT087640MA), under the auspices of the UK Clinical Research Collaboration (RC, RRK, MCS); Medical Research Council (grants G0800612 and G0802736; M.C.S., J.H. and M.H.); and the South West Public Health Training Scheme (G.J.M.).