Understanding the nature of association between anxiety phenotypes and anorexia nervosa: a triangulation approach

BMC Psychiatry

E. Caitlin Lloyd¹  Anne M. Haase²  Bas Verplanken³  Marcus R. Munafò⁴  Hannah M. Sallis⁵ 

[1] Centre for Exercise, Nutrition and Health Sciences, School of Policy Studies, University of Bristol, Bristol, UK;Department of Psychiatry, Columbia University Irving Medical Center, New York, NY, USA;Department of Psychiatry, New York State Psychiatric Institute, New York, NY, USA;Centre for Exercise, Nutrition and Health Sciences, School of Policy Studies, University of Bristol, Bristol, UK;Faculty of Health, Victoria University of Wellington, Wellington, New Zealand;Public Health Sciences Division, Fred Hutchinson Cancer Research Centre, Seattle, Washington, USA;Department of Psychology, University of Bath, Bath, UK;MRC Integrative Epidemiology Unit at the University of Bristol, Bristol, UK;School of Psychological Science, University of Bristol, Bristol, UK;National Institute for Health Research Bristol Biomedical Research Centre at the University Hospitals Bristol NHS Foundation Trust and the University of Bristol, Bristol, UK;MRC Integrative Epidemiology Unit at the University of Bristol, Bristol, UK;School of Psychological Science, University of Bristol, Bristol, UK;Population Health Sciences, Bristol Medical School, University of Bristol, Bristol, UK;

关键词: ALSPAC;    Anorexia nervosa;    Anxiety;    Longitudinal;    Mendelian randomization;    Triangulation;   

DOI  :  10.1186/s12888-020-02883-8

来源: Springer

【 摘 要 】

BackgroundEvidence from observational studies suggests an association between anxiety disorders and anorexia nervosa (AN), but causal inference is complicated by the potential for confounding in these studies. We triangulate evidence across a longitudinal study and a Mendelian randomization (MR) study, to evaluate whether there is support for anxiety disorder phenotypes exerting a causal effect on AN risk.MethodsStudy One assessed longitudinal associations of childhood worry and anxiety disorders with lifetime AN in the Avon Longitudinal Study of Parents and Children cohort. Study Two used two-sample MR to evaluate: causal effects of worry, and genetic liability to anxiety disorders, on AN risk; causal effects of genetic liability to AN on anxiety outcomes; and the causal influence of worry on anxiety disorder development. The independence of effects of worry, relative to depressed affect, on AN and anxiety disorder outcomes, was explored using multivariable MR. Analyses were completed using summary statistics from recent genome-wide association studies.ResultsStudy One did not support an association between worry and subsequent AN, but there was strong evidence for anxiety disorders predicting increased risk of AN. Study Two outcomes supported worry causally increasing AN risk, but did not support a causal effect of anxiety disorders on AN development, or of AN on anxiety disorders/worry. Findings also indicated that worry causally influences anxiety disorder development. Multivariable analysis estimates suggested the influence of worry on both AN and anxiety disorders was independent of depressed affect.ConclusionsOverall our results provide mixed evidence regarding the causal role of anxiety exposures in AN aetiology. The inconsistency between outcomes of Studies One and Two may be explained by limitations surrounding worry assessment in Study One, confounding of the anxiety disorder and AN association in observational research, and low power in MR analyses probing causal effects of genetic liability to anxiety disorders. The evidence for worry acting as a causal risk factor for anxiety disorders and AN supports targeting worry for prevention of both outcomes. Further research should clarify how a tendency to worry translates into AN risk, and whether anxiety disorder pathology exerts any causal effect on AN.

【 授权许可】

CC BY