Taller men may have a lower risk of dementia

New European research has found that men who are taller in young adulthood may have a lower risk of dementia in old age.

Carried out by researchers at Bispebjerg and Frederiksberg Hospital, the University of Copenhagen, and the University of Southern Denmark, the new large-scale study looked at data on 666,333 Danish men born between 1939 and 1959, including 70,608 brothers and 7,388 twins, which was gathered from Danish national registries.

The researchers not only looked at the men's body height, but also whether other factors could impact the risk of dementia.

Lead author Terese Sara Høj Jørgensen explained that "We wanted to see if body height in young men is associated with diagnosis of dementia, while exploring whether intelligence test scores, educational level, and underlying environmental and genetic factors shared by brothers explain the relationship."

The findings, published in eLife, showed that a total of 10,599 men developed dementia later in life. In addition, the researchers also found that there appeared to be a 10 per cent reduction in the risk of developing dementia for around every 6cm of height in individuals above the average height.

After the researchers took intelligence and education into account in their analysis, the association between height and dementia risk was only slightly reduced.

They also found that there was a relationship between height and dementia even when they looked at brothers who were different heights, which they say suggests that genetics and family characteristics alone do not explain why shorter men had a greater dementia risk.

"Together, our results point to an association between taller body height in young men and a lower risk of dementia diagnosis later in life, which persists even when adjusted for educational level and intelligence test scores," says senior author Merete Osler says.

"Our analysis of the data concerning brothers confirms these findings, and suggests the association may have common roots in early-life environmental exposures that are not related to family factors shared by brothers."

Osler added that they cannot be sure if the findings are generalisable to women, as previous studies which have investigated whether there are differences between genders in regard to the relationship between height and dementia have so far proved inconclusive.