Combat Dementia in Military Personnel: A Novel Neurocognitive Profile of Relentless War

We introduce the term "combat dementia" as a novel neurocognitive phenotype that emerges in military personnel as a consequence of prolonged and continuous exposure to combat environments. In a prospective cohort (2014–2025; n = 297), neuropsychological testing (MoCA), cognitive event-related potentials, quantitative EEG, and multidisciplinary clinical evaluation were performed. Three phenotypes of cognitive impairment were distinguished for clinical analysis: (A) post-traumatic brain injury (TBI) with MRI/CT-verified macrostructural changes (classical organic variant); (B) without TBI and PTSD, with no macrostructural alterations on MRI/CT, but with persistent network-level microstructural pathology verified by specific neurophysiological markers (persistent variant, i.e., "combat dementia"); (C) associated with PTSD/cumulative psychotrauma, without neuroimaging evidence of macrostructural lesions or neurophysiological indicators of stable microstructural pathology, but with predominantly functional changes verified by neurophysiological markers and potentially reversible dynamics (transitional/borderline variant). Three distinct trajectories of cognitive decline were identified: macrostructural organic (A), microstructural persistent (B), and transitional/borderline (C). Phenotype C, occupying an intermediate position between A and B, illustrates a possible transformation from functional network-level alterations to stable microstructural pathology, thereby explaining the increased risk of dementia in cases of chronic PTSD. Key predictors of accelerated decline included age and continuous frontline exposure exceeding 14 months, which was associated with nearly a threefold increase in the risk of progression to more severe stages of cognitive impairment. Summarized longitudinal observations (6/12 months; subgroups of 3–10 years) confirm the stability of phenotype B and its distinction from phenotypes A and C; an extended analysis will be presented in subsequent publications. Recognition of combat dementia as an independent clinical entity is critically important for the development of new screening strategies, rehabilitation programs, and nosological classification of cognitive disorders in military populations. The findings delineate a novel domain in neuropsychiatry, with implications not only for Ukraine but also for the international community in shaping humanitarian and social policy, as well as rehabilitation systems and military medical expertise.