Objective: Attention Deficit-Hyperactivity Disorder (ADHD) and Posttraumatic Stress Disorder (PTSD) are often comorbid and share a common core of symptoms. However, sex and gender-related factors significantly influence their prevalence, clinical presentation, and diagnosis. Here, we conducted a systematic literature review and meta-analysis to examine sex differences in ADHD/PTSD comorbidity during childhood and adulthood. Methods: A scoping review of PsycINFO and PubMed yielded 13 eligible studies with complete outcome data. We conducted fixed-effects meta-analyses of the sex-stratified prevalence of ADHD/PTSD using pooled odds ratios (OR) with a 95% confidence interval (CI). Fixed-effects subgroup analyses were performed using age as a subgroup. Effect size heterogeneity was assessed using the I2 index and Cochran's Q test. Results: In the whole sample (N= 13,585; F= 7005, M= 6580), the diagnosis of ADHD/PTSD was significantly higher in females than in males (OR = 1.32, p = 0.02). Between-study heterogeneity was low-to-moderate and not significant (I2 = 41%; p = 0.06), validating the fixed-effects model. Age-stratified subgroup analyses revealed higher ADHD/PTSD odds in females compared to males only in adult populations (OR=1.41; p = 0.01). Additionally, females were more likely to be diagnosed with both disorders in studies where ADHD was the primary diagnosis (OR = 1.60; p = 0.002), and in studies employing structured clinical interviews as diagnostic tools (OR = 1.46; p = 0.009). Conclusions: Our study is the first to show that the association between ADHD and PTSD is stronger in females, suggesting that ADHD may increase risk for PTSD in a sex-specific manner.

The authors have declared no competing interest.

This work was conducted with support from the Mary Horrigan Connors Center for Women's Health and Gender Biology and the Women's Brain Health Initiative, Brigham and Women's Hospital, Boston, MA, USA. We also acknowledge the support from UM1TR004408 award through Harvard Catalyst/The Harvard Clinical and Translational Science Center (National Center for Advancing Translational Sciences, National Institutes of Health) and financial contributions from Harvard University and its affiliated academic healthcare centers.

I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained.

Yes

The details of the IRB/oversight body that provided approval or exemption for the research described are given below:

The study used (or will use) ONLY openly available human data that were originally located at: doi: 10.4088/JCP.12m07698 doi: 10.1111/acps.12011 doi: 10.1016/j.comppsych.2011.12.001 doi: 10.1007/s00787-007-0607-2 doi: 10.1176/ajp.2006.163.4.716 doi: 10.1080/08039488.2021.1962973 doi: 10.1016/j.psychres.2018.04.017 doi: 10.4236/oalib.1111111 doi: 10.1080/15374410802148178 doi: 10.1002/jts.21668 doi: 10.1080/08039480500520665 doi: 10.1177/1087054716677818

I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals.

Yes

I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance).

Yes

I have followed all appropriate research reporting guidelines, such as any relevant EQUATOR Network research reporting checklist(s) and other pertinent material, if applicable.

Yes