Views 1,212
Citations 0
Original Investigation
March 2016

Familial Liability for Eating Disorders and Suicide AttemptsEvidence From a Population Registry in Sweden

Author Affiliations
  • 1Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden
  • 2Department of Psychiatry, University of North Carolina at Chapel Hill
  • 3Department of Psychological and Brain Science, Indiana University, Bloomington
  • 4Astrid Lindgren Children’s Hospital, Karolinska University Hospital, Stockholm, Sweden
  • 5Department of Nutrition, University of North Carolina at Chapel Hill

Copyright 2016 American Medical Association. All Rights Reserved. Applicable FARS/DFARS Restrictions Apply to Government Use.

JAMA Psychiatry. 2016;73(3):284-291. doi:10.1001/jamapsychiatry.2015.2737

Importance  Suicide attempts are common in individuals with eating disorders. More precise understanding of the mechanisms underlying their concomitant occurrence is needed.

Objective  To examine the association between eating disorders and suicide attempts and whether familial risk factors contribute to the association.

Design, Setting, and Participants  A Swedish birth cohort including individuals born in Sweden between January 1, 1979, and December 31, 2001, was followed up from age 6 years to December 31, 2009 (N = 2 268 786). Information was acquired from Swedish national registers. All individuals were linked to their biological full siblings, maternal half siblings, paternal half siblings, full cousins, and half cousins. Data analysis was conducted from October 5, 2014, to April 28, 2015.

Main Outcomes and Measures  Eating disorders were captured by 3 variables (any eating disorder, anorexia nervosa, and bulimia nervosa) identified by any lifetime diagnoses recorded in the registers. Suicide attempts were defined as any suicide attempts, including death by suicide, recorded in the registers. We examined the association between eating disorders and death by suicide separately, but the study was underpowered to explore familial liability for this association.

Results  Of 2 268 786 individuals, 15 457 females (1.40% of all females) and 991 males (0.09% of all males) had any eating disorder, 7680 females (0.70%) and 453 males (0.04%) had anorexia nervosa, and 3349 females (0.30%), and 61 males (0.01%) had bulimia nervosa. Individuals with any eating disorder had an increased risk (reported as odds ratio [95% CI]) of suicide attempts (5.28 [5.04-5.54]) and death by suicide (5.39 [4.00-7.25]). The risks were attenuated but remained significant after adjusting for comorbid major depressive disorder, anxiety disorder, and substance use disorder (suicide attempts: 1.82 [1.72-1.93]; death by suicide: 2.04 [1.49-2.80]). Similar results were found for anorexia nervosa (suicide attempts: crude, 4.42 [4.12-4.74] vs adjusted, 1.70 [1.56-1.85]; death by suicide: crude, 6.46 [4.38-9.54] vs adjusted, 2.67 [1.78-4.01]) and bulimia nervosa (suicide attempts: crude, 6.26 [5.73-6.85] vs adjusted, 1.88 [1.68-2.10]; death by suicide: crude, 4.45 [2.44-8.11] vs adjusted, 1.48 [0.81-2.72]). Individuals (index) who had a full sibling with any eating disorder had an increased risk of suicide attempts (1.41 [1.29-1.53]). The risk was attenuated for any eating disorder in more-distant relatives (maternal half siblings, 1.10 [0.90-1.34]; paternal half siblings, 1.21 [0.98-1.49]; full cousins, 1.11 [1.06-1.18]; half cousins, 0.90 [0.78-1.03]). This familial pattern remained stable after adjusting for the index individuals’ eating disorders. Similar patterns were found for anorexia nervosa and bulimia nervosa.

Conclusions and Relevance  These results suggest an increased risk of suicide attempts in individuals with lifetime eating disorders and their relatives. The pattern of familial coaggregation suggests familial liability for the association between eating disorders and suicide. Psychiatric comorbidities partially explain this association, suggesting particularly high-risk presentations.