Systematic Review and Meta-Analysis: Predictors of Adult Psychiatric Outcomes of Childhood...

Psychiatric disorders are highly prevalent in adults with childhood-onset attention-deficit/hyperactivity disorder (ADHD). Currently, little is known about childhood predictors for these outcomes.

PubMed, PsychInfo, Web of Science, and EMBASE were searched until June 2024. Eligible studies investigated childhood predictors of persistent ADHD, substance use disorders (SUDs), conduct disorder, antisocial personality disorder, major depressive disorder (MDD), and/or anxiety disorders in adults diagnosed with childhood ADHD (PROSPERO #CRD42022320887). Meta-analytic models were tested when N ≥3 for a predictor with similar effect measures, otherwise predictors were discussed narratively when N ≥2. The Newcastle-Ottawa Scale (NOS) was used to assess study quality.

The selected 36 studies included 119 predictors, with 10 predictors eligible for meta-analyses. History of stimulant treatment (odds ratio [OR] = 1.88, 95% CI = 1.28-2.75, p = .001) was associated with increased, and higher childhood IQ with decreased (OR = 0.99, 95% CI = 0.98-1.00, p =.039), risk of ADHD persistence in adulthood. ADHD persistence was associated with increased risk of SUDs (OR = 2.12, 95% CI = 1.53-3.17, p =.004) and MDD (OR = 3.19, 95% CI = 1.71-5.95, p <.001). Narratively reviewed predictors of fair/good quality studies showed potential predictors for ADHD persistence (ie, ADHD combined type, hyperactive/impulsive symptoms, anxiety disorders, externalizing problems, social dysfunctioning, and socioeconomic status).

We confirmed earlier reported childhood predictors (ie, stimulant treatment history, ADHD persistence) and identified potential new predictors (ie, childhood anxiety disorders, social problems, socioeconomic status) for psychiatric outcomes of ADHD. However, the available literature is hampered by methodological shortcomings. Future studies should focus on studying combined effects of potential predictors.

This study systematically evaluated previous research on risk factors for adult psychiatric outcomes of children diagnosed with ADHD. Results showed that those adults who were treated with stimulant medication were twice as likely to still have ADHD in adulthood. Those adults who still had ADHD were at greater risk for also having a substance use disorder and depressive disorder.

Predictors of Long-term Psychiatric Outcomes of Childhood ADHD in Adulthood: a Systematic Review and Meta-Analysis; https://www.crd.york.ac.uk/PROSPERO/view/CRD42022320887.