Why even a cousin with Alzheimer’s raises your risk

HAVING a grandparent or even a cousin with Alzheimer’s disease may raise your risk of developing it.

Many people who have lost a parent to dementia have the nagging fear they may have inherited the condition.

But having more distant relatives with Alzheimer’s disease could be a warning sign, according to a study.

Someone with two grandparents diagnosed with the condition has a 25 per cent higher risk of developing it, researchers found. Two cousins with Alzheimer’s disease can raise someone’s risk by 17 per cent.

The study found a risk from ‘second-degree’ family members, such as grandparents and uncles, and ‘ third-degree’ relatives, such as cousins, being diagnosed with Alzheimer’s.

Experts at the University of Utah analysed medical records and death certificates for 270,800 people in the US, looking at four generations in each case. They found someone with a parent or sibling with Alzheimer’s disease, plus a second- degree relative such as a grandparent, could see their risk of being diagnosed rise 21 times.

The study, published in the journal Neurology, also found risk of Alzheimer’s doubles if three or more second- degree relatives have had it. These relwhen atives include grandparents, blood-related aunts and uncles and half-siblings.

Someone’s danger of the memory-robbing condition also leaps 43 per cent when three of their third-degree relatives have had it. That includes cousins, greatgrandparents, great uncles and great aunts.

Among 5,320 people in this category, 148 people had the disease researchers would have expected 103 to be diagnosed.

More than half of people with Alzheimer’s have a specific gene that triples the risk of getting it, and other genes passed down through families are also thought to increase the risk.

However, some results were based on small numbers of people and the authors stress that lifestyle changes, such as losing weight and reducing high blood pressure, can slash the risk of Alzheimer’s disease by a third.

Dr Lisa Cannon-Albright, of the University of Utah, said: ‘We found that having a broader view of family history may help better predict risk. These results potentially could lead to better diagnoses and help patients and their families in making healthrelated decisions.’

Dr James Pickett, of Alzheimer’s Society, said risk of developing the disease was ‘complex’, but added: ‘By following good lifestyle advice, even people with a strong family history could significantly reduce their risk.’

‘Broader view of family history’