ADHD linked to premature death risk
medwireNews: Patients with attention deficit/hyperactivity disorder (ADHD) have a significantly increased mortality rate, especially if they are diagnosed in adulthood, a study published in The Lancet shows.
This was most prominent in girls and women, although the effect of ADHD on mortality in girls and women was not significantly greater than in boys and men.
“Our findings emphasise the importance [of] diagnosing ADHD early, especially in girls and women, and treating any co-existing antisocial and substance use disorders”, said lead study author Søren Dalsgaard (Aarhus University, Denmark) in a press statement.
“It is however important to emphasise that although the relative risk of premature death is increased in ADHD, the absolute risk is low.”
From among 1,922,248 people in Danish national registries, Dalsgaard and co-workers identified 32,061 with a clinical diagnosis of ADHD. They note that diagnosis of ADHD in Denmark is “more restrictive” than in countries such as the USA, so patients have relatively severe symptoms and/or impairment.
During follow-up to a maximum age of 32 years, 107 ADHD patients died, giving an all-cause mortality rate of 5.85 per 10,000 person–years, compared with 2.21 per 10,000 person–years in individuals without ADHD.
Of the ADHD patients who died, 68.4% did so of unnatural causes, with 77.8% of these being accidents.
After accounting for multiple confounders, patients with ADHD alone had a significantly increased mortality risk ratio (MRR) of 1.5. This rose to 2.17 among the 16.9% of patients with comorbid oppositional defiant disorder or conduct disorder and to 5.63 among the 12.3% with comorbid substance use disorder. Patients with all three diagnoses had an MRR of 8.29.
The MRR of girls and women with ADHD was 3.01, whereas that of boys and men was 1.93. After exclusion of those without the above comorbidities, the MRR remained significant for girls and women, at 2.85, but lost significance for boys and men, at 1.27.
Patients’ age at diagnosis affected their mortality risk, with the MRR rising from 1.86 for those diagnosed before 6 years of age, to 1.58 and 4.25 for those diagnosed at the ages of 6 to 17 years and older than 17 years, respectively.
In a linked commentary, Stephen Faraone (SUNY Upstate Medical University, Syracuse, New York, USA) calls it “disconcerting” that the median age at ADHD diagnosis was 12.3 years, despite symptom onset at 6 years or younger being mandatory for inclusion in the registry.
He suggests that “failure to identify and treat ADHD in a timely manner might worsen the course of the disorder and increase the risk to enter one of the pathways to premature death.”
Faraone concludes: “For clinicians, early identification and treatment should become the rule rather than the exception.”
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