2026 ECNP Congress

PS03-3151

Assessing the ADHD LANDSCAPE in Women: Results from Female Psychiatric Patients

Francoise Truong-Berthoz — A. Parhar, N. Canal Diaz, P. Biedermann, C.B. Skoglund · Takeda Pharmaceuticals International AG, Global Medical Affairs, Zurich, Switzerland

2026 ECNP Congress

Background

The prevalence of ADHD in patients with psychiatric disorders is estimated as 6.9%-38.8%.1 However, diagnoses are often missed or delayed in adults with existing psychological disorders as ADHD symptoms frequently overlap with coincident psychiatric disorders.2,3 Delayed diagnosis or untreated ADHD can exacerbate psychiatric comorbidities, impair outcomes, and increase costs.2 Studies have shown women have comparatively more missed diagnoses than men, and have higher psychiatric comorbidity rates.4,5 Understanding the prevalence and presentation of ADHD in female patients with psychiatric disorders may raise diagnosis rates and improve clinical care in women.

Objectives

The LANDSCAPE study (NCT04943796) assessed health outcomes and the prevalence of ADHD in adult patients with psychiatric disorders. This subgroup analysis focuses exclusively on female patients.

Methods

LANDSCAPE was an observational, prospective, multicentre two-part study in adult outpatients with ≥1 existing psychiatric disorder (≥12 months with major depressive disorder, anxiety disorder, bipolar disorder, substance use disorders, borderline personality disorder, and/or binge eating disorder). Part 1 was a cross-sectional study of patients consecutively assessed for ADHD (per DSM-5 and/or DIVA-5 criteria) across sites from Canada, Germany, Spain, Sweden, Switzerland, and the UK. Part 2 was a prospective, longitudinal 9-month study including all patients from Part 1 who had a confirmed diagnosis of ADHD. The primary outcome for this subgroup analysis is quality-of-life (QoL) over 9 months in female patients. Secondary measures include sociodemographic and clinical characteristics, psychological/psychiatric clinical management, functionality level, and QoL at baseline and over follow-up. This sub-analysis focuses primarily on data from Part 2.

Results

Out of 228 included patients in Part 1, 140 were female, of which 77.1% (n=108) were diagnosed with ADHD; 92 of these patients were included in Part 2. Mean (SD) age was 35.4 (10.5) years, BMI was 27.1 (7.4), and approximately half were married (n=44/92, 47.8%) and half were employed (n=46/92, 50.0%). Nearly half of female patients had a family history of ADHD (n=42/92, 45.7%), and nearly one third had previously attempted suicide (n=27/92, 29.3%). The most common psychological comorbidities were major depressive disorder (n=57/92, 62.0%), anxiety disorder (n=43/92, 46.7%), and substance use disorder (n=17/92, 18.5%). Mean (SD) global clinical impression severity scale scores in female patients improved from 3.7 (1.0) to 3.2 (1.1) (p=0.0003) following ADHD diagnosis. Mean (SD) total female ADHD QoL (AAQoL) scores increased from 39.1 (13.1) at baseline to 48.8 (17.2) at 9 months (p<0.0001), whilst degree of functional impairment (FAST total score) was reduced from 38.1 (10.4) to 32.2 (14.7) (p=0.0018), respectively. Routine monitoring visits increased from the 12 months preceding ADHD diagnosis compared to the following 12 months (n=59/92, 64.1% vs. n=68/83, 81.9%) and mean (SD) trips to healthcare professionals increased overall from 8.5 (11.2) to 15.4 (23.0) over the same period, respectively.

Conclusions

ADHD was frequently identified in adult female populations with existing psychiatric disorders, highlighting an important unmet need and likely delayed diagnosis in this population. The high comorbidity burden, functional impairment and poor QoL at baseline emphasize the impact of ADHD under-recognition in women. Improved QoL and FAST scores suggest that earlier diagnosis may improve clinical outcomes.

References

  1. Gerhand S, Saville CW. ADHD prevalence in the psychiatric population. Int J Psychiatry Clin Pract. 2022;26:165-177.
  2. Katzman MA, Bilkey TS, Chokka PR, et al. Adult ADHD and comorbid disorders: clinical implications of a dimensional approach. BMC Psychiatry. 2017;17:302.
  3. Barkley RA, Brown TE. Unrecognized attention-deficit/hyperactivity disorder in adults presenting with other psychiatric disorders. CNS Spectr. 2008;13:977-984.
  4. Skoglund C, Sundström PI, Leksell D, et al. Time after time: failure to identify and support females with ADHD - a Swedish population register study. J Child Psychol Psychiatry. 2024;65:832-844.
  5. Mestres F, Richarte V, Crespín JJ, et al. Sex differences in adults with attention-deficit/hyperactivity disorder: A population-based study. Eur Psychiatry. 2025;68:e90.