A new study confirms earlier reports that anaemia – a condition caused by having too little haemoglobin, the oxygen-carrying component of red blood cells – increases the risk for dementia. It found that having high haemoglobin levels does so as well.
Dutch researchers looked at 12,305 people without dementia at the start of the study, measuring their haemoglobin levels and following them for an average of 12 years. Over the period, 1,520 developed dementia, including 1,194 with Alzheimer’s disease. The study is in Neurology.
The scientists divided the haemoglobin levels into five groups, low to high. Compared with those in the middle one-fifth, those in the highest fifth had a 20 per cent increased risk for any dementia type, and a 22 per cent increased the risk for Alzheimer’s. Those in the lowest were at a 29 per cent increased risk for dementia and a 36 per cent increased the risk for Alzheimer’s.
The researchers controlled for education level, blood pressure, diabetes, lipid-lowering medication, alcohol intake and other health and behavioural characteristics.
“We don’t have the intervention studies that would show that modifying haemoglobin could prevent dementia,” said the lead author, Frank J. Wolters, a researcher at Erasmus University Medical Center in Rotterdam, “and we can’t recommend interventions based on this study. In the meantime, given the other beneficial effects of treating anaemia, this study provides an extra incentive.”
Source: The New York Times