title: Associations of mortality with own height using son's height as an instrumental variable.
abstract: Height is associated with mortality from many diseases, but it remains unclear whether the association is causal or due to confounding by social factors, genetic pleiotropy,(1) or existing ill-health. The authors investigated whether the association of height with mortality is causal by using a son's height as an instrumental variable (IV) for parents' height among the parents of a cohort of 1,036,963 Swedish men born between 1951 and 1980 who had their height measured at military conscription, aged around 18, between 1969 and 2001. In a two-sample IV analysis adjusting for son's age at examination and secular trends in height, as well as parental age, and socioeconomic position, the hazard ratio (HR) for all-cause paternal mortality per standard deviation (SD, 6.49cm) of height was 0.96 (95% confidence interval (CI): 0.95, 0.96). The results of IV analyses of mortality from all causes, cardiovascular disease (CVD), respiratory disease, cancer, external causes and suicide were comparable to those obtained using son's height as a simple proxy for own height and to conventional analyses of own height in the present data and elsewhere, suggesting that such conventional analyses are not substantially confounded by existing ill-health.
authors.affiliation: MRC Centre for Causal Analyses in Translational Epidemiology (CAiTE), School of Social and Community Medicine, University of Bristol, United Kingdom. David.Carslake@bristol.ac.uk
authors.forename: David
authors.initials: D
authors.lastname: Carslake
authors.forename: Abigail
authors.initials: A
authors.lastname: Fraser
authors.forename: George
authors.initials: G
authors.lastname: Davey Smith
authors.forename: Margaret
authors.initials: M
authors.lastname: May
authors.forename: Tom
authors.initials: T
authors.lastname: Palmer
authors.forename: Jonathan
authors.initials: J
authors.lastname: Sterne
authors.forename: Karri
authors.initials: K
authors.lastname: Silventoinen
authors.forename: Per
authors.initials: P
authors.lastname: Tynelius
authors.forename: Debbie A
authors.initials: DA
authors.lastname: Lawlor
authors.forename: Finn
authors.initials: F
authors.lastname: Rasmussen
mesh_terms: D000293:Adolescent; D000328:Adult; D001827:Body Height; D002423:Cause of Death / Q000639:trends; D016001:Confidence Intervals; D015986:Confounding Factors, Epidemiologic; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D009679:Nuclear Family; D016016:Proportional Hazards Models; D013548:Sweden / Q000453:epidemiology; D055815:Young Adult