title: Association between income trajectories in childhood and psychiatric disorder: a Swedish population-based study.
abstract: Childhood family income variation is an understudied aspect of households' economic context that may have distinct consequences for children. We identified trajectories of childhood family income over a 12-year period, and examined associations between these trajectories and later psychiatric disorders, among individuals born in Sweden between 1987 and 1991 (n=534 294).
  
  
  
  We used annual income data between the ages of 3-14 years and identified 5 trajectories (2 high-income upward, 1 downward and 2 low-income upward trajectories). Psychiatric disorders in the follow-up period after age 15 were defined from International Classification of Disease (ICD)-codes in a nationwide patient register. Multiadjusted risks for all psychiatric disorders, as well as for specific psychiatric diagnoses, were calculated as HRs with 95% CIs.
  
  
  
  Of the 5 identified income trajectories, the constant low and the downward trajectories were particularly associated with later psychiatric disorder. Children with these trajectories had increased risks for psychiatric disorder, including mood, anxiety, psychotic disorders and attention deficit/hyperactivity disorder. The association remained, even after adjusting for important variables including parental psychiatric disorder. In contrast, the relationship was reversed for eating disorders, for which children in higher income trajectories had elevated risks.
  
  
  
  Findings show that children growing up in a household characterised by low or decreasing family income have an increased risk for psychiatric disorder. Continued work is needed to reduce socioeconomic inequalities in psychiatric disorders. Policies and interventions for psychiatric disorders should consider the socioeconomic background of the family as an important risk or protective factor.
authors.affiliation: Department of Community Health Sciences, Fielding School of Public Health and California Center for Population Research, University of California Los Angeles, Los Angeles, California, USA.|Division of Social Medicine, Department of Public Health Sciences, Karolinska Institutet, Stockholm, Sweden.
authors.forename: Emma
authors.initials: E
authors.lastname: Björkenstam
authors.affiliation: Department of Sociology, New York University, New York, New York, USA.
authors.forename: Siwei
authors.initials: S
authors.lastname: Cheng
authors.affiliation: Division of Social Medicine, Department of Public Health Sciences, Karolinska Institutet, Stockholm, Sweden.
authors.forename: Bo
authors.initials: B
authors.lastname: Burström
authors.affiliation: Department of Community Health Sciences, Fielding School of Public Health and California Center for Population Research, University of California Los Angeles, Los Angeles, California, USA.
authors.forename: Anne R
authors.initials: AR
authors.lastname: Pebley
authors.affiliation: Department of Epidemiology, Fielding School of Public Health, University of California, Los Angeles, California, USA.|Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden.|Department of Sociology, Stockholm University, Stockholm, Sweden.
authors.forename: Charlotte
authors.initials: C
authors.lastname: Björkenstam
authors.affiliation: Division of Public Health Epidemiology, Department of Public Health Sciences, Karolinska Institutet, Stockholm, Sweden.|Center for Epidemiology and Community Medicine, Stockholm County Council, Stockholm, Sweden.
authors.forename: Kyriaki
authors.initials: K
authors.lastname: Kosidou
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007182:Income / Q000706:statistics & numerical data*; D008297:Male; D001523:Mental Disorders / Q000453:epidemiology*; D012042:Registries; D012307:Risk Factors; D012959:Socioeconomic Factors; D013548:Sweden / Q000453:epidemiology
keywords: CHILD HEALTH; LONGITUDINAL STUDIES; MENTAL HEALTH; POVERTY; Social and life-course epidemiology