Declaration of interest
That risk factors measured in middle age may not fully explain future dementia risk implicates exposures acting earlier in life. Height may capture early-life illness, adversity, nutrition and psychosocial stress.
To investigate the little-explored association between height and dementia death.
Individual participant meta-analysis using 18 prospective general population cohort studies with identical methodologies (1994-2008; n = 181 800).
Mean follow-up of 9.8 years gave rise to 426 and 667 dementia deaths in men and women respectively. The mean heights were 174.4 cm (s.d. = 7.3) for men and 161.0 cm (s.d. = 6.8) for women. In analyses taking into account multiple covariates, increasing height was related to lower rates of death from dementia in a dose-response pattern (P⩽0.01 for trend). There was evidence of a differential effect by gender (P = 0.016 for interaction). Thus, the association observed in men (hazard ratio per s.d. decrease in height 1.24, 95% CI 1.11-1.39) was markedly stronger than that apparent in women (HR = 1.13, 95% CI 1.03-1.24).
Early-life circumstances, indexed by adult height, may influence later dementia risk.
The Health Survey for England is part of a programme of surveys commissioned by the UK National Health Service (NHS) Information Centre for Health and Social Care, and carried out since 1994 by the Joint Health Surveys Unit of the National Centre for Social Research and the Department of Epidemiology and Public Health at University College London. Currently employed by the University of Edinburgh and the UK NHS, T.C.R. was supported by Alzheimer Scotland during the preparation of this manuscript. T.C.R., J.M.S. and G.D.B. are members of both the Alzheimer Scotland Dementia Research Centre funded by Alzheimer Scotland and the University of Edinburgh Centre for Cognitive Ageing and Cognitive Epidemiology, part of the cross-council Lifelong Health and Wellbeing Initiative (G0700704/84698). Funding from the Biotechnology and Biological Sciences Research Council, the Engineering and Physical Sciences Research Council, the Economic and Social Research Council (ESRC) and the UK Medical Research Council (MRC) is gratefully acknowledged. E.S. is funded by a National Institute for Health Research career development fellowship and M.K. is supported by the MRC (K013351), the US National Institutes of Health (R01HL036310, R01AG034454) and a professorial fellowship from the ESRC.
- Royal College of Psychiatrists