Public health significance of mixed anxiety and depression: beyond current classification.
BACKGROUND
The public health significance of mixed anxiety-depressive disorder (MADD) and the distinctiveness of its phenomenology have yet to be established.


OBJECTIVE
To determine the public health significance of MADD, and to compare its phenomenology with ICD-10 anxiety, depressive, and comorbid anxiety and depressive disorders.


METHODS
Weighted analysis of data from the Great Britain National Psychiatric Morbidity survey was conducted with a representative household sample of 8580 persons aged 16-74 years.


RESULTS
The 1-month prevalence of MADD was 8.8%. A fifth of all days off work in Britain occurred in this group. The symptom profile of MADD was similar to 'pure' ICD-10 anxiety and depression, but with a lower overall symptom count. The disorder was associated with significant impairment of health-related quality of life. Differences in health-related quality of life measures between diagnostic groups were accounted for by overall symptom severity, which remained strongly associated with health-related quality of life measures after adjusting for diagnostic group. The finding that half of the anxiety, depression and MADD cases and a third of the comorbid depression and anxiety cases grouped into a single latent class challenges the notion of these conditions as having distinct phenomenologies. Mixed presentations may be the norm in the population.


CONCLUSIONS
The data support the pathological significance of MADD in its negative impact upon population health. Dimensional approaches to classification may provide a more parsimonious description of anxiety and depressive disorders compared with categorical approaches.
Das-Munshi
Jayati
J
Section of Epidemiology, Institute of Psychiatry, King's College London, De Crespigny Park, London SE5 8AF, UK. spsljdm@iop.kcl.ac.uk
Goldberg
David
D
Bebbington
Paul E
PE
Bhugra
Dinesh K
DK
Brugha
Traolach S
TS
Dewey
Michael E
ME
Jenkins
Rachel
R
Stewart
Rob
R
Prince
Martin
M
D000293:Adolescent; D000328:Adult; D000368:Aged; D001007:Anxiety / Q000175:diagnosis* / Q000453:epidemiology / Q000534:rehabilitation; D001008:Anxiety Disorders / Q000175:diagnosis; D003863:Depression / Q000175:diagnosis* / Q000453:epidemiology / Q000534:rehabilitation; D003866:Depressive Disorder / Q000175:diagnosis; D003937:Diagnosis, Differential; D005260:Female; D006306:Health Surveys; D006801:Humans; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D011569:Psychiatric Status Rating Scales; D011634:Public Health; D011788:Quality of Life; D006113:United Kingdom / Q000453:epidemiology