Children and young people with attention deficit hyperactivity disorder (ADHD) use healthcare services twice as often in the two years before their diagnosis than those who do not have the condition, a study found.
The results suggest that healthcare professionals should consider a potential diagnosis of ADHD in children who use their services frequently, said researchers at the University of Nottingham and King's College London.
ADHD affects an estimated 3%-5% of children and young people, with a peak age for diagnosis between 7 and 9 years of age. However, the neurodevelopmental disorder was likely to have been "present from an earlier age", with persistent symptoms, according to the authors of the study, published in Archives of Disease in Childhood.
Children With ADHD Often Face Long Delays Being Diagnosed
"ADHD is under-recognised," they noted, and the condition is not well understood. Lead author Dr Vibhore Prasad, a GP from Nottinghamshire, said, "We know that children with ADHD often face long delays in diagnosis," and when a diagnosis of ADHD in children and young people was delayed, or missed, this might impede access to effective treatments.
Identifying early markers of, and wider health presentations associated with, undiagnosed ADHD represented an "opportunity to improve recognition and outcomes", the authors proposed.
For the population-based matched case-control observational study the researchers set out to compare use of healthcare services and reasons for attendance by children and young people with ADHD versus non-ADHD controls.
They used data from the Clinical Practice Research Datalink of 8127 children and young people with an ADHD diagnosis aged 4 to 17 years of age at the time of diagnosis, and 40,136 non-ADHD controls — matched by age, sex, and GP practice — between 1998 and 2015.
The research focused on the reasons why children saw their GP, received prescriptions from the GP, attended hospital for overnight admissions, and had operations in hospital.
The investigation found that children and young people with ADHD used health services significantly more than controls, making "twice as much use" of all these services in the two years before diagnosis when compared to children without ADHD, rate ratios were: GP: 2.0, (95% CI 2.0 to 2.1); hospital 1.8, (95% CI 1.8 to 1.9).
The rates of attendance at GP surgeries and hospitals were higher across almost all presentation categories investigated, which included categories such as skin, respiratory, infections, eye, ENT, and oral. The largest differences were seen in mental and neurodevelopmental presentations, but there were also increased rates of physical conditions, such as asthma and eczema, explained the authors.
Earlier Diagnosis Can Prevent Serious Harms to Young People
"The results are significant because we know that identifying ADHD earlier can lead to effective treatment, including talking treatments and medicines, which can prevent a range of serious harms to young people and future adults," said Dr Prasad.
Senior study author Professor Edmund Sonuga-Barke, from the NIHR Maudsley Biomedical Research Centre, and co-author Dr Johnny Downs, a consultant child and adolescent psychiatrist at King's College London, said the study provided a "powerful reminder" of both the physical and mental health difficulties that young people had to confront in the years leading up to an ADHD diagnosis, and that young people with suspected ADHD "may benefit from coordinated multidisciplinary care that can provide holistic support whilst they are waiting for specialist mental health services".
Michele Reilly, lead of Lambeth ADHD Support Group, said the identification of patterns of GP interaction for families with a child with ADHD had provided "valuable insights" into how families navigated the healthcare system and engaged with their GP prior to an ADHD diagnosis.
The research underscored that ADHD should "not be trivialised and reduced" to core symptoms of hyperactivity, impulsivity, and inattention, said Dr Tony Lloyd, CEO of the neurodiversity charity, ADHD Foundation.
The authors urged that more should be done to develop and test interventions to identify ADHD earlier in primary care. There was also a need to urgently review how health services catered for young people with undiagnosed ADHD, they stressed.