A recent study conducted by researchers at University College London has established a significant connection between heart health in middle age and the risk of developing dementia later in life. The findings, published in the European Heart Journal, indicate that individuals exhibiting signs of heart damage during their midlife years are more likely to experience cognitive decline as they age.
The research demonstrated that middle-aged individuals with elevated levels of a protein known as cardiac troponin I in their blood were at an increased risk of dementia. This protein is released into the bloodstream when heart muscle sustains damage. The study tracked nearly 6,000 participants from the long-term Whitehall II study, which has monitored British Civil Service employees since 1985. Notably, researchers identified higher troponin levels in dementia patients compared to their healthy counterparts, with elevated levels detectable up to 25 years prior to a dementia diagnosis.
According to the study, those with the highest baseline troponin levels had a 38% greater likelihood of developing dementia over the course of the study than those with lower levels. This correlation persisted even after adjusting for variables such as sex, ethnicity, and education.
Implications for Future Research
Professor Eric Brunner, the senior author from the UCL Institute of Epidemiology and Health Care, emphasized the importance of monitoring heart health during midlife. He stated, “Poor heart health in middle age puts people at increased risk of dementia in later life.” The study highlights how accumulation of brain damage associated with dementia can develop gradually over decades, suggesting that managing cardiovascular risk factors may mitigate this risk.
The 2024 Lancet Commission on dementia, co-authored by Professor Gill Livingston, estimated that approximately 17% of dementia cases could potentially be prevented or delayed through improved cardiovascular health. These risk factors include managing blood pressure, cholesterol, physical inactivity, and obesity.
Participants in the Whitehall II study underwent a high-sensitivity troponin test between the ages of 45 and 69, with no prior indications of dementia or cardiovascular disease at the time of testing. Over an average follow-up period of 25 years, participants completed cognitive assessments at various intervals, revealing that those with higher troponin levels experienced a more rapid decline in memory and cognitive abilities.
Brain Health Connections
Further analysis involving brain MRI scans of 641 participants indicated that individuals with elevated troponin levels exhibited a smaller hippocampus—an area critical for memory—after 15 years. These participants also showed reduced gray matter volume, typically associated with cognitive processing. The brain scans suggested that the cognitive function of those with high troponin levels was equivalent to that of individuals approximately three years older.
Lead author Dr. Simon Chen highlighted the study’s significance, noting, “Our study represents the longest follow-up to date to investigate links between raised cardiac troponin levels and cognitive decline and dementia.” He added that midlife troponin levels may serve as a more effective biomarker for predicting dementia risk than those measured later in life.
Professor Bryan Williams, Chief Scientific and Medical Officer at the British Heart Foundation, reiterated the study’s implications for heart and brain health, stating, “This study is an important reminder that our heart and brain health are inseparable.” He recommended ongoing attention to heart health throughout life, advising individuals to manage blood pressure, control cholesterol levels, stay active, maintain a healthy weight, and avoid smoking.
The findings underscore the critical intersection of cardiovascular health and cognitive function, highlighting the need for further research to explore the potential of troponin as a predictive tool for dementia risk.
