Discrepancies in Studies on ADHD and COVID-19 Raise Concerns Regarding the Risks of Stimulant Treatments During an Active Pandemic

Two publications by Merzon and colleagues in the Journal of Attention Disorders (JAD) suggest that attention-deficit hyperactivity disorder (ADHD) increases the risk of COVID-19 infections (2020) and severe outcomes (2021). Adherence to stimulant treatments was recommended to attenuate the spread of the pandemic (2020). The conclusions of these timely studies attracted considerable attention, probably due to their wide-scope implications for the public health. But how valid are they? Furthering our earlier critique published in this journal, the current article outlines seven severe gaps in these publications, including inconsistencies in the definitions and rates of ADHD, inadequate definition for ADHD medications, omissions of crucial information, unsuitable analyses, and unmet declarations regarding conflicts of interests and data availability. In fact, the latter, which constitutes a repeated avoidance of data sharing (up to this day, March 28, 2023), seems to have led the editor-in-chief of JAD to propose the write-up of the current article (which he then judged, after the peer review process, as “worthy of publication,” but also that JAD is “not the best placement” of its publication—despite its specific focus on several JAD articles). To complete the picture regarding this burning public health issue, this article also provides a glimpse into the problematic happenings that took place behind the scenes, which included a personal defamation and various stalling tactics, along with an elaborated and fully-referenced response that was sent by the authors of the current article to the reviewers and the editor-in-chief of JAD in real time (Appendix). Together, the discrepancies and problematic ethical conducts that are exposed in the current article suggest that the speculation regarding the link between a neurodevelopmental diagnosis (ADHD) and a respiratory virus (COVID-19) has not been subjected to adequate scientific inquiry. On the contrary, the lack of transparency, the observed gaps, and the existing extensive literature on stimulant-related cardiovascular risks, including the recently published guidelines for starting ADHD medications by one of the authors of the 2021 study, raise concerns regarding the potentially dangerous implications of stimulant use during a global epidemic.