What an ACE score means

The ACE questionnaire asks yes or no to ten kinds of adversity before 18: physical, emotional and sexual abuse; physical and emotional neglect; and five household conditions (domestic violence against a mother, substance misuse, mental illness, an incarcerated member, parental separation or divorce). Each yes adds one point. In the CDC-Kaiser study of 17,337 adults with health insurance and mostly some college, 36% scored zero, 26% one, 16% two, 9.5% three and 12.5% four or more (CDC) [4]. A 25-state survey of 144,017 US adults found 61% with at least one and one in six with four or more [1].

The defining finding of the ACE study was the dose-response shape. Compared with a score of zero, adults with four or more categories had 4 to 12 times the odds of alcoholism, drug misuse, depression and a suicide attempt; 2 to 4 times the odds of smoking, poor self-rated health and sexually transmitted disease; and 1.4 to 1.6 times the odds of severe obesity and physical inactivity [4]. The same paper found graded odds for ischaemic heart disease (2.2), cancer (1.9), stroke (2.4), chronic lung disease (3.9) and diabetes (1.6) at four or more, after adjusting for age, sex, race and education.

A meta-analysis of 37 studies and 253,719 people pooled the odds for four or more ACEs versus none [2]. The weakest links were with physical inactivity (1.3), overweight (1.4) and diabetes (1.5). Stronger ones: heart disease (2.1), cancer (2.3), smoking (2.8), respiratory disease (3.1), anxiety (3.7), depression (4.4), problematic alcohol use (5.8), problematic drug use (10.2) and a suicide attempt (30.1). The authors note that the strongest associations are with behaviours and mental health, the weakest with the diseases those behaviours cause decades later.

In the CDC-Kaiser cohort, people with six or more ACEs died on average at 60.6 versus 79.1 for people with none, almost 20 years earlier*, with 1.7 times the hazard of death before 75 and 2.4 times before 65 [5]. That cohort relied on adult recall. Cohorts that recorded adversity in childhood point the same way: in the 1958 British birth cohort, two or more adversities meant 1.57 times the death rate before 50 for men and 1.80 for women [6], and in a Danish registry of 1.1 million children, the 3% on the highest-adversity trajectory had 4.5 times the death rate between ages 16 and 34 [7].

ACEs reach the adult body through behaviour and through biology. Behaviour first: five or more ACEs meant 2.1 times the odds of current smoking and 5.4 times the odds of starting before 14 [8], 2.1 times the odds of trouble falling or staying asleep and 2.0 times the odds of waking tired [9], and the drinking, inactivity and isolation odds in item 3. In the British cohort the mortality gap was partly explained by adult smoking, drinking and socioeconomic position [6]. Biology too: in the Dunedin cohort, children who were maltreated had 1.8 times the risk of high C-reactive protein at 32, independent of adult stress, health behaviours and weight [10].

The ACE score was built to describe populations. The researchers who created it have written that it is a crude measure with no weighting for severity, frequency or age, that it omits adversities like poverty and discrimination, and that using it to predict or screen an individual’s future health is a misapplication [12]. Adult recall and childhood records also disagree more than people assume: in the Dunedin cohort, retrospective and prospective ACE counts agreed only moderately, with recalled counts better at predicting how people feel and recorded counts better at predicting measured outcomes [13].

Positive experiences count as well as adverse ones. In a Wisconsin survey of 6,188 adults, those who recalled six or seven positive childhood experiences (feeling able to talk to family about feelings, feeling supported, at least two non-parent adults who took an interest, a sense of belonging at school, and so on) had 72% lower odds of depression or poor mental health than those with zero to two, and the association held across every level of ACEs [3]. The adult version of the same finding is the social-ties literature: across 148 studies and 308,849 people, strong social relationships predicted 50% higher odds of survival over the follow-up [14].

For post-traumatic stress after childhood adversity, trauma-focused cognitive behavioural therapy and EMDR are first-line treatments in the UK’s NICE guideline, with the best evidence of any psychological approach (NICE NG116, 2018). Depression that follows maltreatment responds to treatment too, though on average a little less readily: across 16 studies, a history of childhood maltreatment meant 1.43 times the odds of not responding to a given course and 2.27 times the odds of a recurrent or persistent episode [15]. The practical reading is not that treatment fails, but that a first course is more likely to need a second, or a combination.