A Dutch study in a forensic sample of adult males with ADHD has found that diagnosis had often been missed earlier in life, possibly because their ADHD was masked by other factors.
106 adult males with ADHD (mean age 29.4 years) were recruited from an outpatient clinic, having been referred by probation, court or primary healthcare services (women were not included in the analysis due to low numbers). The presence and severity of ADHD symptoms and other psychiatric disorders were determined by a psychiatrist. Using this, along with information from family members and patient records, the researchers aimed to establish whether adults with ADHD in this forensic sample had received an earlier diagnosis, and, using regression analysis, sought to identify factors which might predict a missed diagnosis of ADHD in childhood or adolescence.
The researchers found that over half of participants (56%) had had an ADHD diagnosis missed earlier in life. They also found that a missed diagnosis of ADHD was more likely in older men (odds ratio [OR] 1.08), those with hyperactive/impulsive or combined subtype ADHD (OR 15.69), fewer reported ADHD symptoms in childhood (OR 0.14) and adolescence (OR 0.94), and comorbid mood disorders (OR 4.93). Previous mental health care was a strong predictor of having correctly received a diagnosis of ADHD earlier in life (OR 12.52), but even so, of those who had been previously seen by mental health services, diagnosis was missed in 42% of cases.
In a post-hoc regression analysis which did not include mental health care as a predictor, missing diagnosis was also predicted by prior contact with the police or court (OR 0.31), severity of dysfunction in childhood (OR 0.61) and adolescence (OR 1.70), and comorbid anxiety disorder (OR 11.21), possibly due to a reduced likelihood of being referred to mental health services.
Limitations to the study are more likely to have influenced results of the predictors of missed diagnosis, rather than the primary result of the frequency of missed diagnosis. Overall, the researchers concluded that both general and forensic mental health workers should be aware that a diagnosis of ADHD can often have been missing in adults exhibiting criminal behaviour, where ADHD symptoms can be masked by various factors.
Read more about undetected ADHD diagnoses in criminal adults here
Buitelaar NJ, Ferdinand RF. ADHD undetected in criminal adults. J Atten Disord 2016; 20: 270-278.