title: Mortality after parental death in childhood: a nationwide cohort study from three Nordic countries.
abstract: BACKGROUND
  Bereavement by spousal death and child death in adulthood has been shown to lead to an increased risk of mortality. Maternal death in infancy or parental death in early childhood may have an impact on mortality but evidence has been limited to short-term or selected causes of death. Little is known about long-term or cause-specific mortality after parental death in childhood.
  
  
  RESULTS
  This cohort study included all persons born in Denmark from 1968 to 2008 (n = 2,789,807) and in Sweden from 1973 to 2006 (n = 3,380,301), and a random sample of 89.3% of all born in Finland from 1987 to 2007 (n = 1,131,905). A total of 189,094 persons were included in the exposed cohort when they lost a parent before 18 years old. Log-linear Poisson regression was used to estimate mortality rate ratio (MRR). Parental death was associated with a 50% increased all-cause mortality (MRR = 1.50, 95% CI 1.43-1.58). The risks were increased for most specific cause groups and the highest MRRs were observed when the cause of child death and the cause of parental death were in the same category. Parental unnatural death was associated with a higher mortality risk (MRR = 1.84, 95% CI 1.71-2.00) than parental natural death (MRR = 1.33, 95% CI 1.24-1.41). The magnitude of the associations varied according to type of death and age at bereavement over different follow-up periods. The main limitation of the study is the lack of data on post-bereavement information on the quality of the parent-child relationship, lifestyles, and common physical environment.
  
  
  CONCLUSIONS
  Parental death in childhood or adolescence is associated with increased all-cause mortality into early adulthood. Since an increased mortality reflects both genetic susceptibility and long-term impacts of parental death on health and social well-being, our findings have implications in clinical responses and public health strategies. Please see later in the article for the Editors' Summary.
authors: Section for Epidemiology, Department of Public Health, Aarhus University, Aarhus, Denmark.
authors: Jiong
authors: J
authors: Li
authors: Section for General Practice, Department of Public Health, Aarhus University, Aarhus, Denmark; Research Unit for General Practice, Department of Public Health, Aarhus University, Aarhus, Denmark.
authors: Mogens
authors: M
authors: Vestergaard
authors: Clinical Epidemiology Unit, Department of Medicine, Karolinska Institute, Stockholm, Sweden.
authors: Sven
authors: S
authors: Cnattingius
authors: National Institute for Health and Welfare (THL), Helsinki, Finland.
authors: Mika
authors: M
authors: Gissler
authors: Section for Epidemiology, Department of Public Health, Aarhus University, Aarhus, Denmark.
authors: Bodil Hammer
authors: BH
authors: Bech
authors: Section for General Practice, Department of Public Health, Aarhus University, Aarhus, Denmark; Research Programme for Mental Child Health, Department of Public Health, Aarhus University, Aarhus, Denmark.
authors: Carsten
authors: C
authors: Obel
authors: Section for Epidemiology, Department of Public Health, Aarhus University, Aarhus, Denmark; Department of Epidemiology, School of Public Health, University of California, Los Angeles, California, United States of America.
authors: Jørn
authors: J
authors: Olsen
mesh_terms: D000293:Adolescent; D001601:Bereavement; D002423:Cause of Death; D002648:Child; D046688:Child Mortality; D002675:Child, Preschool; D015331:Cohort Studies; D003718:Denmark / Q000453:epidemiology; D005260:Female; D005387:Finland / Q000453:epidemiology; D006801:Humans; D007223:Infant; D007226:Infant Mortality; D008016:Life Change Events; D008297:Male; D063129:Parental Death / Q000706:statistics & numerical data*; D012307:Risk Factors; D013548:Sweden / Q000453:epidemiology; D013997:Time Factors