ADHD gender gap tied to delayed diagnosis and poor outcomes

Females diagnosed with ADHD later in life are more likely to experience adolescent mental health struggles, teenage pregnancy, secondary school absences, and have more hospital appointments than those diagnosed in early childhood, finds new research. ADHD, a common neurodevelopmental condition, is less likely to be diagnosed in females than males. Females are also more likely than males to be diagnosed later on in life.

Now, a new study by Cardiff University has uncovered new insights into how late diagnosis of ADHD in females can have profound impacts on their mental health and well-being. The research also showed that this group does experience difficulties in early childhood, before their ADHD is recognized and diagnosed. The research, “Antecedents and outcomes of a later attention deficit hyperactivity disorder (ADHD) diagnosis in females,” was published in British Journal of Psychiatry.

Dr. Joanna Martin, Senior Research Fellow at the Wolfson Centre for Young People’s Mental Health and the Centre for Neuropsychiatric Genetics and Genomics at Cardiff University, said, “ADHD is less likely to be diagnosed in girls than in boys, partly due to under-recognition. Not only are girls less likely to be diagnosed with ADHD, but they are also more likely to be diagnosed later in life—leaving them without early interventions and support, and making them more vulnerable to increased risks of developing various mental health problems.

“A better understanding is needed of the impacts and risks of later ADHD diagnosis, and any related potential health, social and educational outcomes, especially in females, who are a historically neglected group in ADHD research and clinical practice.

“In this study, we aimed to address this knowledge gap around the impact of diagnosis, and more specifically, late diagnosis of ADHD in girls and women, using an analysis of health and education linked data from young people across Wales.”

The researchers used nationwide register data from the Secure Anonymised Information Linkage (SAIL) databank—a detailed data repository that covers routinely collected primary and secondary health care, education, and social care data for Wales—to analyze early and late ADHD diagnosis, and mental health, educational and other outcomes later in life. The researchers found:

• Compared with earlier ADHD diagnosis, later diagnosis in females was associated with increased anxiety, depression, self-harm, alcohol use, drug use, bipolar disorder, schizophrenia, anti-anxiety and antidepressant prescriptions, teenage pregnancy, school absences, and more outpatient, inpatient, and emergency contacts.
• These associations were stronger in females than males for depression, self-harm, drug use, bipolar disorder, antidepressant prescriptions, and outpatient, inpatient, and emergency contacts.
• Compared to females without ADHD, females with a later ADHD diagnosis already had clear evidence of neurodevelopmental, mental health and educational difficulties, increased health care use, and socioeconomic deprivation in early childhood, prior to being diagnosed with ADHD.

“Our results demonstrate that later ADHD diagnosis is associated with significant negative outcomes by adolescence, which disproportionately disadvantages females.

“We know that recognition and treatment of ADHD improves long-term social, educational and occupational outcomes, and reduce risks of depression, suicide, substance abuse, accidents, and criminality. Our study adds to this knowledge and is essential for addressing the gender gap in diagnosis and intervention.

“Future studies are needed to examine further differences in ADHD diagnosis timing in adolescence compared to adulthood, as well as to develop improved gender-inclusive assessment tools to aid ADHD diagnosis, especially in females. These are important priorities in my research,” added Dr. Martin.