Researchers from the Alzheimer Scotland Dementia Research Centre at the University of Edinburgh analysed data on 181,800 people for the years 1994-2008 and found that risk of dementia death went down by a factor of 1.24% per inch height increase.
Lead author Dr Tom Russ, of the University of Edinburgh’s College of Medicine & Veterinary Medicine, said: “In these analyses in which we grouped together 18 studies, we found that shorter adult height was associated with an increased risk of subsequent dementia death and that this association was stronger in men than it was in women.”
“The association between height and dementia death remained when we took into account early life or adult socio-economic status and other relevant factors, including obesity, smoking, cardiovascular disease risk factors, and longstanding illness.”
The authors emphasised that being short does not cause dementia, but how tall a person is could inform the study of possible risk factors for dementia.
Senior author Dr David Batty, of the Department of Epidemiology & Public Health at University College London, added: “Short height in itself of course does not ‘cause’ dementia. Rather, height captures a number of early life factors, including early-life illness, adversity, poor nutrition, and psychosocial stress, and so allows us to examine the effect of these factors on dementia more closely.”
The possibility that early life factors could relate to dementia risk needs to be further examined according to the authors, who called for public health policies to improve early life conditions to continue on a broad front including pre-school education, improved parenting schemes and vaccination programmes.
Dementia is a major global health problem and an estimated 36 million people worldwide have the condition. In the UK, the importance of dementia has been highlighted with the publication of national dementia strategies for Scotland and England and the Prime Minister’s ‘Challenge on Dementia’ in 2012 which outlined the importance of increased research activity in defeating this disease.
Reference: Russ TC, Kivimäki M, Starr JM, Stamatakis E and Batty GD. Height in relation to dementia death: individual participant meta-analysis of 18 prospective cohort studies. British Journal of Psychiatry.