Pavilion Publishing and Media Ltd
Blue Sky Offices Shoreham, 25 Cecil Pashley Way, Shoreham-by-Sea, West Sussex, BN43 5FF, UNITED KINGDOM
Tel: +44 (0)1273 434 943
Email: [email protected]
Abnormal haemoglobin levels – detected through routine health checks – could be linked to an increased risk of dementia, according to a new study
The study, presented at the European College of Neuropsychopharmacology (ECNP Congress in Munich and published in the Journal of Alzheimer’s Disease. It found that people in the lowest 20% of haemoglobin levels had a 16% higher risk of all-cause dementia than those in the group with the lowest dementia rate, whereas those in the highest 20% had a 7% higher risk.
The study followed 316,542 Korean adults aged 40 and over who had a national health screening in 2004–2005, then used national health insurance records to track new dementia diagnoses until the end of 2019 — up to 15 years later.
For Alzheimer’s disease, the increased risk was mainly seen amongst the 20% of people with the lowest haemoglobin levels, who had a 14% higher risk than the reference group. For vascular dementia (caused by reduced blood flow to the brain), the 20% with the lowest haemoglobin levels had a 19% higher risk, whereas the 20% with the highest haemoglobin levels had an 18% greater risk of developing dementia.
Dementia and association with haemoglobin levels
Although the authors say more work is needed to understand the risk, the findings suggest that abnormal haemoglobin levels may be a visible marker of broader physical vulnerability relevant to brain health. They also stress that this was an observational study and so comes with several caveats. It can identify associations, but it cannot prove that low or high haemoglobin directly causes dementia. Early, undiagnosed dementia processes may also affect nutrition, frailty, weight loss, or anaemia, which could contribute to the observed relationship.
Haemoglobin is already measured in standard blood tests and is often already available in routine medical records. Low haemoglobin is commonly associated with anaemia, while unusually high haemoglobin may reflect smoking, dehydration, lung or heart disease, or other medical conditions.
Presenting the work at the 39th ECNP Congress in Munich, lead researcher Dr Hyun Soo Kim, assistant professor at Dong-A University College of Medicine, Busan, South Korea, said: “The findings do not show that haemoglobin itself causes dementia, but dementia is one of the fastest-growing health challenges in aging societies, and there are not many treatments and no cure. Identifying simple, accessible markers of future risk could help researchers and clinicians better understand how whole-body health relates to brain health over time”.
“A blood test most people already get at a routine check-up may say something about their brain health many years later. In this large Korean cohort, people with unusually low haemoglobin — and, to a smaller degree, those with unusually high haemoglobin — were more likely to develop dementia. This does not prove that haemoglobin causes dementia, but it supports the idea that general physical health, including the body’s ability to carry oxygen, matters for long-term brain health”.
