New Research: Sex Differences Impact ADHD Symptoms, Treatment Efficacy
September 15, 2026
Sex differences exert a significant and complex impact on ADHD symptoms, treatment, and risk of co-occurring conditions, according to the findings of several recent studies.
Most recently, researchers from Denmark found that individuals with ADHD faced relatively greater risk of developing 13 physical conditions, and that risk ratio was significantly affected by the sex of the patient.1 Research on the impact of menstrual cycle hormones on ADHD symptoms further illuminated the notable influence of sex on ADHD symptomatology and impairment.2 Finally, a study on the efficacy of cognitive behavioral therapy (CBT) for adolescents with ADHD also revealed differences across the sex divide.
Sex Impacts Risk of Physical Conditions
People with ADHD demonstrate a higher risk for 13 physical conditions, including endocrine, metabolic, and eye conditions, according to a study that used medical records of more than 800,000 Danish individuals. The study, published in the Journal of Attention Disorders, found that individuals diagnosed with ADHD showed a higher risk for all conditions, apart from malignant neoplasms, beginning in adolescence.
Having an ADHD diagnosis did not raise this risk equally for men and women, however.
In the general population, females were at a higher risk of most physical conditions beginning in adolescence. Specifically, females were nine times more likely to have an endocrine, nutritional, or metabolic disorder beginning in young adulthood. However, when researchers measured rates in females with an ADHD diagnosis, the relative prevalence fell by half.
In another case, males in the general population had a 15% higher risk than females of developing eye and adnexa diseases in childhood. Among those with an ADHD diagnosis, though, this trend was reversed; females had double the risk of males.
Sex and Hormonal Fluctuations Impact Symptoms
One notable difference in ADHD presentations between males and females stems from fluctuating symptoms over the menstrual cycle. The impact of estrogen on ADHD has been a primary research focus for Michelle Martel, Ph.D., chair of the psychology department at the University of Kentucky, who wrote this in the ADDitude article “Hormonal Changes in Women with ADHD: 4 Gaping Holes in Research:” “Each menstrual cycle brings hormonal peaks and valleys that significantly influence ADHD symptoms. Our recent research confirms that anxiety, mood, and attention all worsen as estrogen falls during the luteal phase.”
Prompted by the promising findings of a small study in 2018,4 Martel conducted a larger-scale study on ADHD symptoms and menstrual hormones. She recently presented her findings at the U.S. Psychiatric and Mental Health Congress.
Martel’s team collected daily measurements of hormone levels and ADHD symptoms from 97 female college students with an ADHD diagnosis and found ADHD symptoms, including impulsivity and inattention, increased in the days preceding and beginning their period.
“These studies have dramatic assessment and treatment implications,” Martel stated in a press release. “We should be paying attention to these things when we’re doing assessments, and then also we may want to change our treatments or personalize our treatments based on where women and girls are across their lifespan.”
Sex Impacts Efficacy of Treatment
A third study exploring yet another facet of sex differences focused on the varying impact of CBT on adolescent males and females with ADHD. Data from 200 teens who participated in randomized control trials in Norway or the Netherlands was analyzed.
According to parent reports, CBT significantly improved ADHD symptoms generally, however this improvement varied depending on the patient’s sex as well as accompanying symptoms of depression.
- CBT led to a significantly smaller reduction in ADHD symptoms for girls with higher levels of depression symptoms, compared to boys with these symptoms.
- For girls, receiving individual CBT (versus group CBT), led to double the improvement in ADHD symptoms.
Each of these studies sheds light on the highly complex and variable nature of ADHD symptoms, treatment, and co-occurring conditions and the still poorly understood ways in which sex differences may affect these realms.
Sources
1Villumsen, M. D., Bilenberg, N., & Steinhausen, H.-C. (2026). Sex Differences in the Association Between Attention-Deficit Hyperactivity Disorder and Physical Diseases in Childhood and Adolescence Using Nationwide Birth Cohorts. Journal of Attention Disorders, 0(0). https://doi.org/10.1177/10870547261448260/
2Harper K. How menstrual periods can affect ADHD symptoms and treatment. Scientific American. May 2026. https://www.scientificamerican.com/article/adhd-symptoms-can-fluctuate-with-the-menstrual-cycle/
3Hanes, T. K., Andersen, A. C., Boyer, B. E., & Wagner, K. (2026). Gender Differences in Cognitive Behavioral Therapy Outcomes for Adolescents With ADHD: Examining the Impact of Internalizing Symptoms. Journal of Attention Disorders, 30(7), 945-954. https://doi.org/10.1177/10870547251415431
4Roberts B, Eisenlohr-Moul T, Martel MM. Reproductive steroids and ADHD symptoms across the menstrual cycle. Psychoneuroendocrinology. 2018;88:105-114. doi:10.1016/j.psyneuen.2017.11.015.