LONDON — As the FIFA World Cup showcases the athleticism of elite soccer, new research suggests that years of repeated heading and other blows to the head may be linked to subtle but detectable brain changes long before dementia would typically emerge.

Researchers found that former elite soccer players reported significantly more symptoms of depression, anxiety, and executive dysfunction than matched controls and had lower gray matter volume on MRI, despite performing similarly on objective cognitive testing.

“These findings suggest there may be measurable effects on brain health in former elite soccer players even in midlife, before clinically apparent neurodegenerative disease would typically emerge,” lead author Caleigh Lynch, MSc, from Imperial College London and the UK Dementia Research Institute, both in London, England, said in a statement.

The findings were presented on July 12 at the Alzheimer’s Association International Conference (AAIC) 2026.

A Sign of Neurodegeneration?

The study included 142 former elite soccer players aged 30-60 years (median age, 44 years), including 126 men who had played professionally for at least 3 years and 16 women who had competed in the top two tiers of the women’s professional game in the UK. The players reported a median of 3 lifetime concussions (interquartile range, 2-7).

They were compared with 56 healthy control participants of similar age without a history of contact sports, military service, repetitive head impacts, concussion, or neurologic disease.

Participants underwent validated symptom questionnaires, standardized neuropsychological testing, and structural brain MRI with voxel-based morphometry analysis.

Interim analyses revealed that former players reported significantly greater symptom burden across multiple domains, including depression, anxiety, post-concussion symptoms, and self-reported executive dysfunction.

Nearly one third (31%) met the threshold for clinically significant depressive symptoms compared with 9% of control participants, whereas 42% had clinically significant anxiety symptoms compared with 25% of control participants.

Objective neuropsychological testing revealed no statistically significant differences between former players and control participants after adjusting for relevant cofactors.

“The absence of measurable differences on objective cognitive testing is reassuring,” Lynch told Medscape Medical News. “Depression, anxiety, and subjective cognitive complaints are common in the general population and can arise from many causes that are not necessarily related to neurodegenerative disease, so it is difficult to conclude whether these symptoms are directly linked to repetitive head impacts,” she added.

Structural MRI findings, however, identified group-level differences. Compared with control participants, former players had lower gray matter volume in frontal, cingulate, and thalamic brain regions involved in memory, attention, decision-making, and emotional regulation.

Although the differences were statistically significant at the group level, only about 2% of individual scans showed clinically relevant atrophy after review by a neuroradiologist, Lynch noted, and she cautioned against overinterpreting the imaging findings.

“Determining whether these findings reflect early neurodegenerative changes, the cumulative effects of soccer participation and repetitive head impacts, or intrinsic differences among individuals who pursue a professional soccer career is a challenge,” said Lynch.

Participants will undergo repeat evaluations every 2 years, including imaging, symptoms, cognitive, and biomarker assessments, to determine whether the observed differences change over time or predict neurologic outcomes.

No Clinical Implications Yet

In an interview with Medscape Medical News, Maria C. Carrillo, PhD, chief science officer and medical affairs lead for the Alzheimer’s Association, said the findings highlight the importance of paying attention to behavioral symptoms in former soccer players, even before memory impairment develops.

“The neuropsychiatric complaints were the primary complaints, and they should be treated and followed longitudinally. We can start to see some of those behavioral changes even before memory changes, hinting that there is some brain degeneration,” Carrillo said.

Although the findings do not warrant an immediate change in clinical management, Carrillo encouraged clinicians to pay closer attention to former elite soccer players with histories of repetitive hits to the head, treat depression, anxiety, and other neuropsychiatric symptoms as appropriate, and counsel patients about continued exposure to head trauma.

The study had no commercial funding. The authors had no disclosures.