Short arms or legs mean a strong candidate for dementia

People with shorter arms and legs may be at a higher risk for developing dementia later in life compared to people with longer arms and legs, possibly due to poor nutrition in early life, which can affect limb growth, according to a study published in the journal Neurology.

The finding tracks several studies earlier that showed how early life environment plays an important role in susceptibility to chronic disease later in life.

“Body measurements such as knee height and arm span are often used as biological indicators of early life deficits, such as a lack of nutrients,” said Tina L Huang, PhD, who was with Johns Hopkins University in Baltimore, when the study started.  Huang is now with the Jean Mayer United States Department of Agriculture (USDA), Human Nutrition Research Center on Aging at Tufts University in Boston.

“Because the development of the brain region most severely affected by Alzheimer’s disease coincides with the greatest change in limb length, we thought it was possible that men and women with shorter limbs could be at greater risk for developing dementia and Alzheimer’s disease,” she said.

Huang says there is a strong correlation between height and socio-economic background, and trends are reflected as early as the first two years of life.

“Reduced height for age, or stunting, is thought to be most closely tied to environment and the quality of diet in early life, which corresponds with periods of the fastest leg growth,” said Huang.

“As a result, environment in the first years of life may play an important role in determining future dementia risk.”

“Our findings are consistent with other studies that have been done in Korean populations, where shorter limb length was associated with greater risk of dementia,” said Huang.

The study was supported by grants from the National Institute on Aging, the National Heart, Lung and Blood Institute and the National Institute of Health.