Generalized anxiety disorder — overview
TL;DR — GAD is defined by persistent, excessive, difficult-to-control worry with associated arousal symptoms lasting ≥6 months (DeMartini 2019, PMID 30934083). DSM-5 interview estimates across 26 countries are 3.7% lifetime and 1.8% 12-month prevalence; half of lifetime cases had severe role impairment (Ruscio 2017, PMID 28297020). Antidepressants improve response versus placebo (RR 1.41, 95% CI 1.29–1.55; NNTB 7; Kopcalic 2025, PMID 39880377), CBT improves symptoms versus treatment as usual (SMD −0.74, −1.09 to −0.38; Papola 2024, PMID 37851421), and continuation escitalopram reduced relapse from 56% to 19% in responders (Allgulander 2006, PMID 16316482). The diagnosis remains contested: deleting excessiveness would raise global lifetime prevalence from 2.6% to 4.0% (Ruscio 2024, PMID 39364896), and taxometric analyses find dimensional structure (Marcus 2014, PMID 24377439). Pooled anxiety-disorder evidence is distinguished from GAD-specific evidence throughout. In a nine-disorder comparison, GAD had the second-largest pre-post placebo change (d_av 1.23, 95% CI 1.06–1.41), which contextualises—but does not explain—small drug–placebo differences (Bschor 2024, PMID 38809560). A 2026 synthesis estimated all-cause mortality RR 1.48 and natural-cause mortality RR 1.55 (Wagner 2026, PMID 42136520). Among treated respondents in World Mental Health surveys, 70% perceived treatment as helpful; modelling estimated that 29.7% would persist through up to 10 professionals, rather than that everyone must reach a tenth encounter (Stein 2021, PMID 34372811).
The condition in five sentences
Generalized anxiety disorder is defined around diffuse worry rather than a discrete phobic stimulus. It is common, female-predominant, chronic and highly comorbid: cross-national lifetime comorbidity was 81.9%, including 63.0% with mood disorders (Ruscio 2017, PMID 28297020). In primary care, clinicians recognised an emotional problem in 72.5% of pure-GAD patients but named GAD correctly in 34.4% (Wittchen 2002, PMID 12044105). Acute, continuation and collaborative-care studies use different populations, comparators and outcomes, so their effect sizes cannot rank one modality as universally “most effective.” The underlying unresolved question is whether the current threshold identifies a distinct disorder or a clinically useful point on a continuum shared with depression.
Three borders that define this condition's scope
- This condition owns GAD, not anxiety. Panic disorder, social anxiety disorder, specific phobias, agoraphobia and separation anxiety are not curated here; OCD is excluded and is in any case no longer classified as an anxiety disorder in DSM-5. Pooled sources appear where they must, and are labelled pooled each time. A pooled anxiety-disorder effect size is not a GAD effect size — the clearest illustration being the reference placebo-controlled CBT meta-analysis, whose overall Hedges' g=0.56 conceals large effects for GAD and small ones for PTSD, social anxiety and panic (Carpenter 2018, PMID 29451967).
- Comorbid depression is cross-linked, not absorbed. Genetic correlation between GAD and major depression approaches unity in women (rg=+1.00) (Kendler 2007, PMID 17121688), yet pure GAD is common in primary care (3.8% vs 1.6% comorbid) and impairs as much as pure MDD (Wittchen 2002, PMID 12044105; Hoffman 2008, PMID 17146763). Depression is curated separately.
- PTSD is a neighbour, not a subset. Seeded alongside this condition; each cross-links the other rather than restating it.
Map of the condition
Foundations
| Page |
What it settles |
| Diagnosis and classification |
The DSM-5 and ICD-11 criteria, where each element came from, the instruments used to apply them, and a reliability record that has been weak since 1983 |
| The diagnostic boundary |
The live dispute: excessiveness, uncontrollability, duration, symptom count; taxometrics; separability from depression; HiTOP and RDoC; the pooling hazard |
| Epidemiology and burden |
Prevalence from 0.4% to 7.4% depending on criteria, instrument and country; disability; the treatment gap |
Mechanism and measurement
| Page |
What it settles |
| Mechanism and models |
Five psychological models of worry-as-avoidance; intolerance of uncertainty and its transdiagnostic problem; neuroimaging, autonomic and genetic findings |
| Screening and measurement |
GAD-7 sensitivity 0.64 pooled versus 0.89 in development; the HAM-A as trial endpoint; USPSTF screening policy without a screening trial |
Treatment
Course, populations and practice
| Page |
What it settles |
| Course, relapse and long-term outcome |
0.38 five-year remission in clinic cohorts versus 52% symptom-free in a community cohort; comorbidity and personality as prognostic drivers; cardiovascular outcomes |
| Special populations |
Children (CAMS), older adults (an analysis-dependent result), perinatal (4.1%/5.7% GAD-specific) |
| Comorbidity and primary care |
The 34.4% correct-diagnosis rate; collaborative care with NNT ~5 |
| Guidelines |
Universal agreement on first line; disagreement on benzodiazepines, pregabalin, screening and duration; no current APA guideline for GAD |
| Clinical trials landscape |
The placebo problem; MM120 in phase 3; the live NCT pipeline |
| Red flags and safety concerns |
Suicidality including subthreshold; thyroid and other mimics; medication harms with numbers |
| Patient experience and advocacy |
A small but non-singular qualitative literature; preference strong enough to terminate a trial; the organisational landscape |
The numbers worth memorising
| Quantity |
Value |
Source |
| Lifetime prevalence, DSM-5, 26 countries |
3.7% (SE 0.1); 12-month 1.8% |
Ruscio 2017, PMID 28297020 |
| Lifetime prevalence without the excessiveness criterion |
4.0% (vs 2.6% with it) |
Ruscio 2024, PMID 39364896 |
| Severe role impairment, lifetime cases |
50.6% |
Ruscio 2017, PMID 28297020 |
| Lifetime comorbidity |
81.9%; mood 63.0% |
Ruscio 2017, PMID 28297020 |
| Antidepressant response vs placebo |
RR 1.41 (1.29–1.55), NNTB 7; AE-dropout NNTH 17 |
Kopcalic 2025, PMID 39880377 |
| Best-ranked drug effect (HAM-A MD) |
Quetiapine −3.60; duloxetine −3.13; pregabalin −2.79; venlafaxine −2.69; escitalopram −2.45 |
Slee 2019, PMID 30712879 |
| CBT vs treatment as usual |
SMD −0.74 (−1.09 to −0.38); third-wave −0.76; relaxation −0.59 |
Papola 2024, PMID 37851421 |
| CBT at ≥12 months in GAD |
Hedges' g=0.22 (k=10) — smallest among anxiety disorders |
van Dis 2020, PMID 31758858 |
| Relapse off vs on escitalopram |
56% vs 19% over 24–76 weeks |
Allgulander 2006, PMID 16316482 |
| Five-year remission probability (clinic cohort) |
0.38 |
Yonkers 2000, PMID 10974960 |
| Placebo pre-post effect in GAD trials |
d_av 1.23 (1.06–1.41) — second-highest of nine disorders |
Bschor 2024, PMID 38809560 |
| GAD-7 at ≥10, pooled |
Sensitivity 0.64 (0.56–0.72), specificity 0.91 (0.87–0.93) |
Aktürk 2025, PMID 40130828 |
| Collaborative care in primary care |
NNT 5.27 response, 5.50 remission at 12 months |
Roy-Byrne 2010, PMID 20483968 |
| Treatment gap |
75.7% (India); 96.1% not seeking help (Bangladesh); ~50% untreated (WMH) |
Jayasankar 2023, PMID 38298878; Sarkar 2025, PMID 41061374; Ruscio 2017, PMID 28297020 |
| All-cause mortality |
RR 1.48 (1.23–1.78); suicide mortality RR 1.93 (1.17–3.17); natural-cause RR 1.55 (1.19–2.02) |
Wagner 2026, PMID 42136520 (165 studies, 7.4M people with anxiety/stress-related disorders) |
| Treatment perceived helpful, of those treated |
70%; but only 34.6% ever obtain treatment and just 29.7% would persist through enough professionals to reach the modelled ceiling |
Stein 2021, PMID 34372811 |
| Placebo pre-post effect |
d_av 1.23 (1.06–1.41), second of nine psychiatric disorders |
Bschor 2024, PMID 38809560 |
Where this condition is genuinely unresolved
- Should excessive worry remain a required criterion? Published, from the group that produced the cross-national epidemiology, and unanswered (Ruscio 2024, PMID 39364896).
- What works for GAD without comorbid depression? The trials either exclude comorbidity or allow all of it (Kopcalic 2025, PMID 39880377; Chen 2019, PMID 31494377).
- Does screening change outcomes, or only detection? A B recommendation issued with no positive screening trial (USPSTF 2023, PMID 37338866; O'Connor 2023, PMID 37338868).
- What maintains remission over years rather than weeks? Longest acute-phase trial: 28 weeks; disorder measured in decades.
- Is guided digital CBT equivalent to face-to-face CBT in GAD? Two evidence bases, opposite answers (Pauley 2023, PMID 34047264; Liu 2025, PMID 40506439).
Full tiered set with a "dots not yet connected" table: OPEN-QUESTIONS.md.
Reading paths
Related pages
Every page in this condition is listed in the map above. Neighbouring conditions: PTSD and depression.
References
- DeMartini J, et al. Generalized Anxiety Disorder. Ann Intern Med. 2019;170:ITC49-ITC64. PMID 30934083
- Ruscio AM, et al. Cross-sectional Comparison of the Epidemiology of DSM-5 Generalized Anxiety Disorder Across the Globe. JAMA Psychiatry. 2017;74:465-475. PMID 28297020
- Ruscio AM, et al. The case for eliminating excessive worry as a requirement for generalized anxiety disorder. Psychol Med. 2024;54:3447-3458. PMID 39364896
- Marcus DK, et al. The latent structure of generalized anxiety disorder in midlife adults. Psychiatry Res. 2014;215:366-71. PMID 24377439
- Kopcalic K, et al. Antidepressants versus placebo for generalised anxiety disorder (GAD). Cochrane Database Syst Rev. 2025;1:CD012942. PMID 39880377
- Papola D, et al. Psychotherapies for Generalized Anxiety Disorder in Adults. JAMA Psychiatry. 2024;81:250-259. PMID 37851421
- Allgulander C, et al. Prevention of relapse in generalized anxiety disorder by escitalopram treatment. Int J Neuropsychopharmacol. 2006;9:495-505. PMID 16316482
- Bschor T, et al. Differential Outcomes of Placebo Treatment Across 9 Psychiatric Disorders. JAMA Psychiatry. 2024;81:757-768. PMID 38809560
- Lijster JM, et al. The Age of Onset of Anxiety Disorders. Can J Psychiatry. 2017;62:237-246. PMID 27310233
- Wittchen HU, et al. Generalized anxiety and depression in primary care: prevalence, recognition, and management. J Clin Psychiatry. 2002;63 Suppl 8:24-34. PMID 12044105
- Roy-Byrne P, et al. Delivery of evidence-based treatment for multiple anxiety disorders in primary care: a randomized controlled trial. JAMA. 2010;303:1921-8. PMID 20483968
- Carpenter JK, et al. Cognitive behavioral therapy for anxiety and related disorders: A meta-analysis of randomized placebo-controlled trials. Depress Anxiety. 2018;35:502-514. PMID 29451967
- Kendler KS, et al. The sources of co-morbidity between major depression and generalized anxiety disorder in a Swedish national twin sample. Psychol Med. 2007;37:453-62. PMID 17121688
- Hoffman DL, et al. Human and economic burden of generalized anxiety disorder. Depress Anxiety. 2008;25:72-90. PMID 17146763
- Slee A, et al. Pharmacological treatments for generalised anxiety disorder: a systematic review and network meta-analysis. Lancet. 2019;393:768-777. PMID 30712879
- van Dis EAM, et al. Long-term Outcomes of Cognitive Behavioral Therapy for Anxiety-Related Disorders. JAMA Psychiatry. 2020;77:265-273. PMID 31758858
- Yonkers KA, et al. Factors predicting the clinical course of generalised anxiety disorder. Br J Psychiatry. 2000;176:544-9. PMID 10974960
- Aktürk Z, et al. Generalized Anxiety Disorder 7-item (GAD-7) and 2-item (GAD-2) scales for detecting anxiety disorders in adults. Cochrane Database Syst Rev. 2025;3:CD015455. PMID 40130828
- Jayasankar P, et al. Current prevalence and determinants of generalized anxiety disorder from a nationally representative, population-based survey of India. Indian J Psychiatry. 2023;65:1244-1248. PMID 38298878
- Sarkar AA, et al. Prevalence, correlates, and treatment gap of generalized anxiety disorder among adults in Bangladesh. J Anxiety Disord. 2025;116:103077. PMID 41061374
- Chen TR, et al. Pharmacological and psychological interventions for generalized anxiety disorder in adults: A network meta-analysis. J Psychiatr Res. 2019;118:73-83. PMID 31494377
- US Preventive Services Task Force. Screening for Anxiety Disorders in Adults. JAMA. 2023;329:2163-2170. PMID 37338866
- O'Connor EA, et al. Anxiety Screening: Evidence Report and Systematic Review for the US Preventive Services Task Force. JAMA. 2023;329:2171-2184. PMID 37338868
- Pauley D, et al. Two decades of digital interventions for anxiety disorders. Psychol Med. 2023;53:567-579. PMID 34047264
- Liu S, et al. CBT treatment delivery formats for generalized anxiety disorder. Transl Psychiatry. 2025;15:197. PMID 40506439
- Wagner E, et al. Risk of all-cause and cause-specific mortality, and suicide attempt in people with anxiety and stress-related disorders: a systematic review, meta-analysis and meta-regression analysis of 165 studies. World Psychiatry. 2026;25:307-320. PMID 42136520
- Stein DJ, et al. Perceived helpfulness of treatment for generalized anxiety disorder: a World Mental Health Surveys report. BMC Psychiatry. 2021;21:392. PMID 34372811