A recent study led by researchers from University College London has revealed a significant link between heart health in midlife and the risk of developing dementia later in life. Published in the European Heart Journal, the research indicates that elevated levels of a protein known as cardiac troponin I during middle age correlate with a higher likelihood of dementia diagnosis years later.
The study analyzed data from nearly 6,000 participants in the long-term Whitehall II study, which has tracked individuals working in the British Civil Service since 1985. Researchers found that participants who exhibited higher troponin levels—indicative of heart muscle damage—were diagnosed with dementia an average of 25 years later. This suggests that silent heart damage may have far-reaching effects on brain health.
In detail, cardiac troponin is released into the bloodstream when the heart muscle sustains damage. While doctors typically monitor high levels of troponin to diagnose heart attacks, elevated but asymptomatic levels may signal ongoing heart issues. These, in turn, can impair blood flow to the brain, potentially leading to cognitive decline and dementia.
Longitudinal Findings on Cognitive Decline
According to the study, participants with the highest troponin levels had a 38% increased risk of developing dementia compared to those with the lowest levels. Researchers tracked cognitive performance over the years, noting that individuals with higher troponin levels experienced a more rapid decline in memory, thinking, and problem-solving abilities. By the time they reached the age of 80, their cognitive abilities were comparable to those of individuals nearly a year and a half older.
The research team, led by Dr. Simon Chen from UCL Psychiatry, noted that the findings represent the longest follow-up study to date examining the relationship between cardiac troponin levels and cognitive health. They also highlighted that the correlation between elevated troponin and dementia risk is more pronounced in midlife than in later years. This suggests that midlife measurements of troponin could serve as critical biomarkers for predicting dementia.
In a subgroup analysis involving 641 participants who underwent MRI scans, researchers found that individuals with the highest troponin levels tended to have a smaller hippocampus—a key brain region for memory—15 years later. These participants also showed reduced gray matter volume, which is essential for processing information. The results indicated that the brain health of these individuals resembled that of people three years older.
Implications for Heart and Brain Health
The senior author of the study, Professor Eric Brunner, emphasized the importance of managing cardiovascular risk factors such as high blood pressure in midlife. He stated, “Poor heart health in middle age puts people at increased risk of dementia in later life.” The research aligns with findings from the 2024 Lancet Commission on dementia, which estimated that 17% of dementia cases could be prevented or delayed through improved management of cardiovascular health.
Professor Gill Livingston, a co-author of the paper, underscored the need for further studies to explore how troponin levels may enhance dementia risk assessment. The findings reinforce the notion that heart and brain health are interconnected, particularly during midlife, a critical period for health interventions.
Professor Bryan Williams, Chief Scientific and Medical Officer at the British Heart Foundation, added, “This study is an important reminder that our heart and brain health are inseparable.” He urged individuals to focus on cardiovascular health throughout their lives by controlling blood pressure, managing cholesterol levels, maintaining physical activity, and avoiding smoking.
The implications of this study are profound, suggesting that proactive measures to improve heart health could also help mitigate the risks of dementia in the aging population. As research continues, understanding the intricate relationship between heart health and cognitive function will be essential for developing effective strategies to combat dementia.
