A growing body of research identifies the harmful effects that adverse childhood experiences (ACEs; occurring during childhood or adolescence; eg, child maltreatment or exposure to domestic violence) have on health throughout life. Studies have quantified such effects for individual ACEs. However, ACEs frequently co-occur and no synthesis of findings from studies measuring the effect of multiple ACE types has been done. In this systematic review and meta-analysis, we searched five electronic databases for cross-sectional, case-control, or cohort studies published up to May 6, 2016, reporting risks of health outcomes, consisting of substance use, sexual health, mental health, weight and physical exercise, violence, and physical health status and conditions, associated with multiple ACEs. We selected articles that presented risk estimates for individuals with at least four ACEs compared with those with none for outcomes with sufficient data for meta-analysis (at least four populations). Included studies also focused on adults aged at least 18 years with a sample size of at least 100. We excluded studies based on high-risk or clinical populations. We extracted data from published reports. We calculated pooled odds ratios (ORs) using a random-effects model. Of 11 621 references identified by the search, 37 included studies provided risk estimates for 23 outcomes, with a total of 253 719 participants. Individuals with at least four ACEs were at increased risk of all health outcomes compared with individuals with no ACEs. Associations were weak or modest for physical inactivity, overweight or obesity, and diabetes (ORs of less than two); moderate for smoking, heavy alcohol use, poor self-rated health, cancer, heart disease, and respiratory disease (ORs of two to three), strong for sexual risk taking, mental ill health, and problematic alcohol use (ORs of more than three to six), and strongest for problematic drug use and interpersonal and self-directed violence (ORs of more than seven). We identified considerable heterogeneity (I2 of >75%) between estimates for almost half of the outcomes. To have multiple ACEs is a major risk factor for many health conditions. The outcomes most strongly associated with multiple ACEs represent ACE risks for the next generation (eg, violence, mental illness, and substance use). To sustain improvements in public health requires a shift in focus to include prevention of ACEs, resilience building, and ACE-informed service provision. The Sustainable Development Goals provide a global platform to reduce ACEs and their life-course effect on health. Public Health Wales.

An increasing number of studies are identifying associations between adverse childhood experiences (ACEs) and ill health throughout the life course. We aimed to calculate the proportions of major risk factors for and causes of ill health that are attributable to one or multiple types of ACE and the associated financial costs. In this systematic review and meta-analysis, we searched for studies in which risk data in individuals with ACEs were compared with these data in those without ACEs. We searched six electronic databases (MEDLINE, CINAHL, PsycINFO, Applied Social Sciences Index and Abstracts, Criminal Justice Databases, and the Education Resources Information Center) for quantitative studies published between Jan 1, 1990, and July 11, 2018, that reported risks of health-related behaviours and causes of ill health in adults that were associated with cumulative measures of ACEs (ie, number of ACEs). We included studies in adults in populations that did not have a high risk of ACEs, that had sample sizes of at least 1000 people, and that provided ACE prevalence data. We calculated the pooled RR for risk factors (harmful alcohol use, illicit drug use, smoking, and obesity) and causes of ill health (cancer, diabetes, cardiovascular disease, respiratory disease, anxiety, and depression) associated with ACEs. RRs were used to estimate the population-attributable fractions (PAFs) of risk attributable to ACEs and the disability-adjusted life-years (DALYs) and financial costs associated with ACEs. This study was prospectively registered in PROSPERO (CRD42018090356). Of 4387 unique articles found following our initial search, after review of the titles (and abstracts, when the title was relevant), we assessed 880 (20%) full-text articles. We considered 221 (25%) full-text articles for inclusion, of which 23 (10%) articles met all selection criteria for our meta-analysis. We found a pooled prevalence of 23·5% of individuals (95% CI 18·7-28·5) with one ACE and 18·7% (14·7-23·2) with two or more ACEs in Europe (from ten studies) and of 23·4% of individuals (22·0-24·8) with one ACE and 35·0% (31·6-38·4) with two or more ACEs in north America (from nine studies). Illicit drug use had the highest PAFs associated with ACEs of all the risk factors assessed in both regions (34·1% in Europe; 41·1% in north America). In both regions, PAFs of causes of ill health were highest for mental illness outcomes: ACEs were attributed to about 30% of cases of anxiety and 40% of cases of depression in north America and more than a quarter of both conditions in Europe. Costs of cardiovascular disease attributable to ACEs were substantially higher than for most other causes of ill health because of higher DALYs for this condition. Total annual costs attributable to ACEs were estimated to be US$581 billion in Europe and $748 billion in north America. More than 75% of these costs arose in individuals with two or more ACEs. Millions of adults across Europe and north America live with a legacy of ACEs. Our findings suggest that a 10% reduction in ACE prevalence could equate to annual savings of 3 million DALYs or $105 billion. Programmes to prevent ACEs and moderate their effects are available. Rebalancing expenditure towards ensuring safe and nurturing childhoods would be economically beneficial and relieve pressures on health-care systems. World Health Organization Regional Office for Europe.

Studies suggest strong links between adverse childhood experiences (ACEs) and poor adult health and social outcomes. However, the use of such studies in non-US populations is relatively scarce. Retrospective cross-sectional survey of 1500 residents and 67 substance users aged 18–70 years in a relatively deprived and ethnically diverse UK population. Increasing ACEs were strongly related to adverse behavioural, health and social outcomes. Compared with those with 0 ACEs, individuals with 4+ ACEs had adjusted odds ratios of the following: 3.96 [95% confidence interval (CI): 2.74–5.73] for smoking; 3.72 (95% CI: 2.37–5.85) for heavy drinking; 8.83 (95% CI: 4.42–17.62) for incarceration and 3.02 (95% CI: 1.38–6.62) for morbid obesity. They also had greater risk of poor educational and employment outcomes; low mental wellbeing and life satisfaction; recent violence involvement; recent inpatient hospital care and chronic health conditions. Higher ACEs were also associated with having caused/been unintentionally pregnant aged <18 years and having been born to a mother aged <20 years. ACEs contribute to poor life-course health and social outcomes in a UK population. That ACEs are linked to involvement in violence, early unplanned pregnancy, incarceration, and unemployment suggests a cyclic effect where those with higher ACE counts have higher risks of exposing their own children to ACEs.

Whilst alcohol and drug use among young people is known to escalate during short holidays and working breaks in international nightlife resorts, little empirical data are available on the impact of longer backpacking holidays on substance use. Here we examine changes in alcohol, tobacco and drug use when UK residents go backpacking in Australia. Matched information on alcohol and drug use in Australia and the UK was collected through a cross sectional cohort study of 1008 UK nationals aged 18–35 years, holidaying in Sydney or Cairns, Australia, during 2005. The use of alcohol and other drugs by UK backpackers visiting Australia was common with use of illicit drugs being substantially higher than in peers of the same age in their home country. Individuals showed a significant increase in frequency of alcohol consumption in Australia compared to their behaviour in the UK with the proportion drinking five or more times per week rising from 20.7% (UK) to 40.3% (Australia). Relatively few individuals were recruited into drug use in Australia (3.0%, cannabis; 2.7% ecstasy; 0.7%, methamphetamine). However, over half of the sample (55.0%) used at least one illicit drug when backpacking. Risk factors for illicit drug use while backpacking were being regular club goers, being male, Sydney based, travelling without a partner or spouse, having been in Australia more than four weeks, Australia being the only destination on their vacation and drinking or smoking five or more days a week. As countries actively seek to attract more international backpacker tourists, interventions must be developed that target this population's risk behaviours. Developing messages on drunkenness and other drug use specifically for backpackers could help minimise their health risks directly (e.g. adverse drug reactions) and indirectly (e.g. accidents and violence) as well as negative impacts on the host country.