The prevalence and burden of subthreshold generalized anxiety disorder: a systematic review

Abstract

BackgroundTo review the prevalence and impact of generalized anxiety disorder (GAD) below the diagnostic threshold and explore its treatment needs in times of scarce healthcare resources.MethodsA systematic literature search was conducted until January 2013 using PUBMED/MEDLINE, PSYCINFO, EMBASE and reference lists to identify epidemiological studies of subthreshold GAD, i.e. GAD symptoms that do not reach the current thresholds of DSM-III-R, DSM-IV or ICD-10. Quality of all included studies was assessed and median prevalences of subthreshold GAD were calculated for different subpopulations.ResultsInclusion criteria led to 15 high-quality and 3 low-quality epidemiological studies with a total of 48,214 participants being reviewed. Whilst GAD proved to be a common mental health disorder, the prevalence for subthreshold GAD was twice that for the full syndrome. Subthreshold GAD is typically persistent, causing considerably more suffering and impairment in psychosocial and work functioning, benzodiazepine and primary health care use, than in non-anxious individuals. Subthreshold GAD can also increase the risk of onset and worsen the course of a range of comorbid mental health, pain and somatic disorders; further increasing costs. Results are robust against bias due to low study quality.ConclusionsSubthreshold GAD is a common, recurrent and impairing disease with verifiable morbidity that claims significant healthcare resources. As such, it should receive additional research and clinical attention.

A systematic review of reviews on the prevalence of anxiety disorders in adult populations

“…In this review, older age groups showed the lowest estimates of past‐year subthreshold GAD (3%) (Haller et al. 2014). …”

“…2006; Haller et al. 2014). In one review, response rates across studies ranged from 45.9% to 99.5% (Steel et al.…”

“…15–35 years Prev. lowest in East Asia [2.8% (2.2–3.4%)] and highest in North America & North Africa/Middle East [7.7%, (6.8–8.8%) vs.7.7% (6.0–10%)] Haller 2014 Search: 2006 # incl. studies: 18 Meta‐analysis: no Pop‐based studies of subthreshold DSM/ICD GAD in adults 15–96 years Range: 90–17,739 General population and primary care sample Clinical and community settings Mostly North American and European data Diagnostic criteria 12‐month median prev.…”

“…studies 91 Meta‐analysis: yes Original studies Limited or no data from Central Asia, Andean Latin America, Oceania, Central sub‐Saharan Africa, Central Europe, South‐east Asia Possibly biased population samples (ex. conflict region studies may have oversampled those exposed to conflict) Review NR 10 Haller 2014 Search: 2006 # incl. studies: 18 Meta‐analysis: no Clarify subthreshold GAD vs. nonpathological anxiety – use impairment criterion for this Should treatment strategies used for threshold disorders be used for subthreshold cases?…”

The relationship between chronic physical conditions, multimorbidity and anxiety in the general population: A global perspective across 42 countries

“…Anxiety is a common and disabling mental health condition [1]. It can greatly impair a person's functioning, quality of life and well-being [2].…”