Casting wider nets for anxiety and depression: disability-driven cross-diagnostic subtypes in a large cohort.
In search of empirical classifications of depression and anxiety, most subtyping studies focus solely on symptoms and do so within a single disorder. This study aimed to identify and validate cross-diagnostic subtypes by simultaneously considering symptoms of depression and anxiety, and disability measures.



A large cohort of adults (Lifelines, n = 73 403) had a full assessment of 16 symptoms of mood and anxiety disorders, and measurement of physical, social and occupational disability. The best-fitting subtyping model was identified by comparing different hybrid mixture models with and without disability covariates on fit criteria in an independent test sample. The best model's classes were compared across a range of external variables.



The best-fitting Mixed Measurement Item Response Theory model with disability covariates identified five classes. Accounting for disability improved differentiation between people reporting isolated non-specific symptoms ['Somatic' (13.0%), and 'Worried' (14.0%)] and psychopathological symptoms ['Subclinical' (8.8%), and 'Clinical' (3.3%)]. Classes showed distinct associations with clinically relevant external variables [e.g. somatization: odds ratio (OR) 8.1-12.3, and chronic stress: OR 3.7-4.4]. The Subclinical class reported symptomatology at subthreshold levels while experiencing disability. No pure depression or anxiety, but only mixed classes were found.



An empirical classification model, incorporating both symptoms and disability identified clearly distinct cross-diagnostic subtypes, indicating that diagnostic nets should be cast wider than current phenomenology-based categorical systems.
University of Groningen, University Medical Center Groningen,Interdisciplinary Center Psychopathology and Emotion regulation (ICPE),Groningen,The Netherlands.
R B K
RB
Wanders
University of Groningen, University Medical Center Groningen,Interdisciplinary Center Psychopathology and Emotion regulation (ICPE),Groningen,The Netherlands.
H M
HM
van Loo
Department of Methodology and Statistics,Tilburg University,Tilburg,The Netherlands.
J K
JK
Vermunt
Department of Psychometrics and Statistics,University of Groningen,Groningen,The Netherlands.
R R
RR
Meijer
Department of Psychiatry,University of Groningen, University Medical Center Groningen,Groningen,The Netherlands.
C A
CA
Hartman
Department of Psychiatry,University of Groningen, University Medical Center Groningen,Groningen,The Netherlands.
R A
RA
Schoevers
University of Groningen, University Medical Center Groningen,Interdisciplinary Center Psychopathology and Emotion regulation (ICPE),Groningen,The Netherlands.
K J
KJ
Wardenaar
University of Groningen, University Medical Center Groningen,Interdisciplinary Center Psychopathology and Emotion regulation (ICPE),Groningen,The Netherlands.
P
P
de Jonge
D000203:Activities of Daily Living; D000293:Adolescent; D000328:Adult; D000368:Aged; D000379:Agoraphobia / Q000503:physiopathology / Q000523:psychology; D001007:Anxiety / Q000503:physiopathology / Q000523:psychology*; D001008:Anxiety Disorders / Q000503:physiopathology / Q000523:psychology*; D015331:Cohort Studies; D003863:Depression / Q000503:physiopathology / Q000523:psychology*; D003865:Major Depressive Disorder / Q000503:physiopathology / Q000523:psychology*; D004185:Disability Evaluation; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009426:Netherlands; D016584:Panic Disorder / Q000503:physiopathology / Q000523:psychology; D000072861:Phobia, Social / Q000503:physiopathology / Q000523:psychology; D012919:Social Behavior; D055815:Young Adult
Anxiety; depression; disability; latent variable mixture modelling; subtypes