People from north ‘more at risk’ of dementia

People living further north have a greater risk of developing dementia, new research by Edinburgh University has suggested.

A study published in the journal Epidemiology today looked at rates of dementia in Scotland and Sweden and found a higher occurrence of dementia among people living in northern parts. The findings could halve dementia rates, the authors claim.

Dementia is any illness affecting the brain which makes it harder to remember things or think as clearly as before. It can be caused by alcohol-related brain damage, damage to arteries which reduce blood flow to the brain, or Alzheimer’s disease. There are 856,700 people in the UK with dementia, 70,000 of them in Scotland. The number is expected to increase by 40 per cent in the next 12 years.

The Edinburgh University study in Scotland, carried out at the Alzheimer Scotland Dementia Research Centre, mapped the disease among people born in 1921, and revealed a change in risk depending on where they currently live. While there was a substantial change the further north people live, there was no change linked to where they had grown up, so experts say it is likely to be caused by common environmental factors such as sunlight exposure and vitamin D.

Dr Tom Russ, of the University of Edinburgh’s Alzheimer Scotland Dementia Research Centre and the Division of Psychiatry, says: “If this geographical variation in dementia risk is the result of one or more environmental risk factors, and if these could be improved in the whole population, our findings suggest that it might be possible to halve dementia rates.”

Jim Pearson, Deputy Director for Policy at Alzheimer Scotland said: "Irrespective of the exact environmental factors involved, this study highlights the importance of providing good services and support to our remote and rural areas, many of which are in the north of Scotland. Nobody should have to face dementia alone, particularly as a result of where they live."

The findings coincide with other work the university is doing on healthy ageing