Anxiety and Depression: Why They Commonly Co-Occur
Updated: Oct 8
Author: Ukrainian Psychological Hub · Published: October 1, 2026 · Editorial Policy
Anxiety and depression commonly occur together because their risk structures overlap and because each can shape the conditions in which the other becomes more likely. That does not make them the same disorder, and it does not mean that one always causes the other. A large systematic review and meta-analysis by Saha and colleagues found robust comorbidity between mood and anxiety disorders across many diagnostic pairs and study designs, while a longitudinal meta-analysis by Jacobson and Newman found that anxiety predicted later depression and depression predicted later anxiety at the group level.
The phrase “anxiety and depression” can describe several different realities: ordinary anxiety plus low mood during a difficult period, anxiety symptoms within a depressive episode, depressive symptoms in someone with an anxiety disorder, two fully diagnosable disorders occurring together, or a different clinical presentation that requires its own assessment. WHO’s current anxiety-disorders guidance distinguishes anxiety disorders from occasional anxiety, and WHO’s depression guidance distinguishes depressive disorder from ordinary changes in mood. A symptom combination is therefore not automatically a diagnosis.
This article owns the broad anxiety–depression co-occurrence intent: why the two commonly appear together, what the strongest evidence says about shared and bidirectional pathways, how symptom overlap is handled clinically, and what comorbidity means for assessment and treatment planning. It does not replace disorder-specific diagnosis or treatment pages.
For the anxiety-disorder family itself, see Anxiety Disorders: Symptoms, Types, Diagnosis, and Treatment.
Anxiety and Depression at a Glance
Anxiety is an emotion and a symptom domain before it is a diagnosis. Fear can be an adaptive response to immediate threat; worry can be a normal attempt to anticipate future problems; stress can temporarily increase arousal, vigilance, sleep difficulty, and irritability. An anxiety disorder is a disorder-specific clinical pattern in which fear, anxiety, worry, or avoidance becomes persistent or excessive enough to cause substantial distress or impairment. The American Psychiatric Association’s current overview describes generalized anxiety disorder, panic disorder, agoraphobia, social anxiety disorder, specific phobia, separation anxiety disorder, and selective mutism as distinct anxiety disorders rather than interchangeable versions of one condition.
Depression likewise refers to more than feeling sad. NIMH describes depression as an illness that can cause significant changes in mood, thinking, sleep, appetite, energy, and daily functioning, while WHO emphasizes persistent depressed mood or loss of pleasure or interest. Those features can coexist with anxiety, but anxiety does not by itself establish a depressive disorder.
Comorbidity means that two diagnosable disorders occur in the same person during a defined time frame. It is descriptive. The term does not prove that one disorder caused the other, that both share one mechanism, or that they should be treated with one identical protocol.
What “Anxiety and Depression” Can Mean
Normal emotions occurring together
A person can feel anxious and low at the same time without having either an anxiety disorder or a depressive disorder. Bereavement, relationship conflict, financial uncertainty, illness, sleep loss, work strain, caregiving, and other stressors can produce fear, worry, fatigue, reduced motivation, tearfulness, or discouragement. Clinical assessment asks whether the pattern has the duration, severity, functional impact, and disorder-specific features needed for a diagnosis.
Symptoms that cross diagnostic boundaries
Sleep disturbance, concentration difficulty, fatigue, irritability, reduced activity, and physical tension are not exclusive to one disorder. The same symptom can arise through different processes. Fatigue, for example, can follow hyperarousal and poor sleep in chronic anxiety, psychomotor and motivational changes in depression, a medical condition, medication effects, substance use, or several factors at once. Symptom overlap helps explain why people can experience both syndromes, but it cannot establish which diagnosis is present.
Two disorders present at the same time
A person can meet diagnostic requirements for an anxiety disorder and a depressive disorder concurrently. The important clinical question is then not which label “wins,” but which specific disorders are present, which symptoms are most impairing or risky, how the timeline developed, and whether one treatment plan can address both without neglecting disorder-specific needs.
A mixed presentation that is not simply two full diagnoses
Classification also recognizes that some people have clinically significant mixed symptoms without meeting full requirements for a separate anxiety disorder and a separate depressive disorder. The WHO ICD-11 Clinical Descriptions and Diagnostic Requirements includes Mixed depressive and anxiety disorder within depressive disorders. That category should not be treated as a casual synonym for “I feel anxious and depressed,” and it is not the same thing as having two independently established disorders.
How Common Is Anxiety–Depression Comorbidity?
The most defensible answer is that it is common, but there is no single percentage that applies to every population, age group, diagnosis, time frame, or setting. Saha et al.’s systematic review and meta-analysis included 171 studies and generated 90 separate pooled analyses after sorting estimates by diagnostic breadth, time frame, temporal order, and adjustment. Every pooled odds ratio was above 1, and the median odds ratio across those analyses was 6.1. The important conclusion is the consistency of the association, not a universal prevalence figure.
Absolute percentages vary because a lifetime estimate is different from a 12-month estimate, community samples differ from treatment-seeking samples, and “anxiety disorder” can mean a broad family or a specific diagnosis. Studies also use different interviews, thresholds, ages, and exclusion rules. A single dramatic percentage stripped from that context is poor clinical communication.
The Netherlands Study of Depression and Anxiety offers a useful clinical-course perspective. Ter Meulen and colleagues’ 2021 synthesis of 76 NESDA papers found extensive comorbidity and frequent transitions between depressive and anxiety disorders in that cohort, with greater symptom burden and functional impairment among people with comorbidity. NESDA is highly informative, but it is still one research program with its own recruitment design; its exact proportions should not be generalized to every population.
Why Anxiety and Depression Commonly Co-Occur
No single mechanism explains the relationship. The evidence fits a layered model in which broad vulnerability, specific learning histories, stressful environments, behavior patterns, cognitive processes, biological liability, and the consequences of living with one disorder can converge. The weight of each layer differs across people.
Shared broad vulnerability
Some characteristics increase risk across multiple forms of internalizing psychopathology rather than pointing to one diagnosis. A prominent example is neuroticism, a trait reflecting a tendency toward frequent and intense negative emotional states. Jeronimus and colleagues’ meta-analysis of 59 longitudinal studies with more than 443,000 participants found that neuroticism prospectively predicted common mental disorders, including anxiety and depression. Adjustment for baseline symptoms and psychiatric history reduced the association substantially, which is precisely why neuroticism should be understood as a broad risk indicator rather than a deterministic cause.
Shared vulnerability helps explain statistical co-occurrence while preserving diagnostic differences. Two disorders can draw on some of the same risk architecture and still have distinct organizing features, triggers, time courses, and treatment targets.
Shared genetic liability
Genetic evidence also supports partial overlap. A 2022 cross-trait genomic analysis by Mei and colleagues reported a significant positive genetic correlation between major depressive disorder and anxiety/stress-related disorders. Genetic correlation describes shared population-level genetic influences; it does not mean there is an “anxiety-and-depression gene,” and it cannot tell an individual why their symptoms developed.
Genetic liability is therefore one contributor within a larger developmental system. Environment, learning, relationships, physical health, stress exposure, sleep, substances, and prior episodes can alter whether vulnerability becomes clinically expressed and what form it takes.
Intolerance of uncertainty
Difficulty tolerating uncertainty can feed both anxious anticipation and depressive rumination. McEvoy and colleagues’ 2019 meta-analysis found a substantial transdiagnostic association between intolerance of uncertainty and symptoms across generalized anxiety disorder, social anxiety disorder, panic disorder, agoraphobia, OCD, depression, and eating disorders. The association was heterogeneous, so intolerance of uncertainty is better treated as one cross-cutting process than as a universal explanation.
In daily life this process can look like repeated attempts to obtain certainty about health, relationships, performance, the future, or one’s own emotional state. When certainty remains impossible, worry may intensify. If repeated checking, reassurance, or avoidance increasingly constricts life, low mood and loss of reinforcement can follow. That sequence is plausible and clinically common, but it should not be assumed in every case.
Repetitive negative thinking
Worry and rumination differ in emphasis but share a repetitive, difficult-to-disengage quality. Worry often leans toward anticipated threat and “what if” scenarios; depressive rumination often circles loss, failure, self-evaluation, or why one feels bad. In some people the content shifts while the repetitive thinking style remains. This creates a bridge between anxious and depressive symptom networks without making worry and rumination identical.
Avoidance and behavioral narrowing
Anxiety can encourage avoidance of feared situations, uncertainty, body sensations, evaluation, travel, conflict, or decisions. Avoidance may reduce distress immediately, which makes it more likely to be repeated. Over time, a person can lose access to social connection, mastery, movement, work opportunities, and rewarding experiences. That narrowing can create conditions in which depressive symptoms become more likely.
The learning mechanism is examined in more detail in Anxiety and Avoidance: How Avoidance Maintains Fear. Avoidance is a maintaining process in many fear and anxiety presentations, but it is not a diagnosis and its role varies by disorder.
Functional consequences can become part of the cycle
A long period of anxiety can make ordinary tasks feel effortful. Sleep may deteriorate. Concentration can become less reliable. Social plans may be canceled. Work or school performance can suffer. A person may start judging themselves for these consequences. In turn, reduced activity, lost confidence, isolation, and a sense of being trapped can intensify depressive symptoms. The clinically useful point is the feedback loop, not a claim that anxiety mechanically produces depression.
Depression can create conditions that amplify anxiety
The pathway can also run in the other direction. Depression can reduce energy, initiative, concentration, social contact, and confidence. Tasks accumulate, finances or academic demands may become harder to manage, and previously ordinary decisions may feel less controllable. These real consequences can increase uncertainty and threat anticipation. Some people also become anxious about whether they will recover, whether they can function, or whether others will notice changes in them.
Shared biology does not imply one brain disorder
Research on genes, stress systems, neurotransmission, and brain networks supports overlapping biology across internalizing disorders, but the findings do not collapse anxiety and depression into one disease. Biological studies are influenced by diagnostic heterogeneity, medication exposure, episode status, age, and study design. At present there is no single biomarker, neurotransmitter level, brain scan, or circuit test that explains why a particular person has both conditions.
Which Usually Comes First?
There is no universal sequence. In some cohorts anxiety disorders begin earlier on average and often precede depression, particularly because several anxiety disorders commonly begin in childhood or adolescence. The NESDA synthesis found anxiety frequently preceded depression in its cohort. That observation is useful for developmental thinking, but it is not a rule for individuals.
The broader longitudinal literature supports reciprocity. Jacobson and Newman’s meta-analysis of 66 studies involving 88,336 people found that anxiety symptoms predicted later depressive symptoms and depressive symptoms predicted later anxiety symptoms. At the diagnostic level, anxiety diagnoses predicted later depressive diagnoses and depressive diagnoses predicted later anxiety diagnoses with very similar effect sizes. The evidence therefore argues against a one-way story.
For an individual, the timeline still matters. Clinicians often ask when worry, panic, avoidance, depressed mood, loss of interest, sleep change, and functional decline first appeared; whether there were symptom-free periods; what happened around each change; and which problem currently creates the greatest impairment or safety concern.
Can Anxiety Cause Depression?
Anxiety can be a risk factor for later depression, and there are plausible pathways from persistent anxiety to depressive symptoms. Long-lasting fear or worry can produce exhaustion, avoidance, social restriction, loss of valued activity, disrupted sleep, and a sense that life is becoming smaller. Those consequences can increase depressive risk.
The careful formulation is “anxiety can contribute to the development of depression in some people,” not “anxiety inevitably turns into depression.” Longitudinal association is not proof of one direct causal mechanism. Shared vulnerabilities may produce both conditions, outside stressors may affect both, and depression may emerge through pathways that are only partly related to the earlier anxiety.
Can Depression Cause Anxiety?
Yes, depression can also precede later anxiety at the population level. Reduced functioning may generate new uncertainty, practical stress, and fear about the future. Loss of confidence can make social or performance situations feel more threatening. Physical sensations associated with sleep disruption, appetite change, inactivity, or medication can also become objects of worry.
Again, the direction is probabilistic rather than inevitable. The longitudinal meta-analysis found bidirectional prediction, so a clinician should not assume that the diagnosis mentioned first is automatically the “root cause” of everything that follows.
Anxiety and Depression Share Symptoms Without Becoming the Same Disorder
Overlap is one reason self-diagnosis can be difficult. Both anxiety and depression can involve sleep disturbance, fatigue, concentration problems, irritability, reduced social functioning, and physical complaints. People can also experience both agitation and low energy at different times. These common features are clinically meaningful but diagnostically nonspecific.
Patterns that organize anxiety
Anxiety presentations are organized around fear, worry, threat anticipation, panic, or avoidance, depending on the disorder. Generalized anxiety disorder centers on difficult-to-control worry across multiple domains. Panic disorder centers on recurrent unexpected panic attacks plus persistent concern or behavior change related to further attacks. Social anxiety disorder centers on fear of negative evaluation in social situations. Specific phobia, agoraphobia, separation anxiety disorder, and selective mutism have their own organizing patterns.
Patterns that organize depression
Depressive disorders are organized around a sustained depressive syndrome in which depressed mood and/or loss of interest or pleasure is central, accompanied by changes that can involve energy, sleep, appetite, thinking, movement, self-evaluation, and thoughts about death. WHO and NIMH both emphasize that clinically significant depression extends beyond ordinary fluctuations in mood.
The same symptom can carry different meaning
Difficulty concentrating during anxiety may reflect attention repeatedly captured by possible threat. During depression it may accompany slowed thinking, low motivation, poor sleep, or persistent negative thought. A person with both conditions may experience several of these processes together. Diagnosis depends on the whole pattern, not on assigning each symptom to a single box.
Important Diagnostic Boundaries
Generalized anxiety disorder and depression
GAD and depressive disorders often co-occur, but broad worry and a depressive syndrome remain different clinical patterns. NIMH’s GAD overview describes persistent, difficult-to-control anxiety and dread as central to GAD and notes that depression commonly co-occurs. The question is whether each syndrome meets its own diagnostic requirements, not whether fatigue or sleep difficulty appears on both symptom lists.
For the narrower disorder-to-disorder comparison, see GAD vs Depression: Worry, Mood, Energy, and Comorbidity.
Panic attacks, panic disorder, and depression
A panic attack can occur during depression without establishing panic disorder. Panic disorder requires its own pattern of recurrent unexpected attacks and persistent concern or behavior change related to further attacks. Depression can coexist with panic disorder, but the presence of one diagnosis does not automatically imply the other.
The panic-specific comorbidity boundary is covered in Panic Disorder and Depression: Comorbidity, Symptoms, and Treatment Planning.
OCD and PTSD are neighboring diagnoses, not anxiety-disorder subtypes
Obsessive-compulsive disorder and post-traumatic stress disorder can include intense anxiety and can co-occur with depression, but current major classification systems place them outside the main anxiety-disorders family. Their core mechanisms and treatment pathways should not be absorbed into a generic “anxiety and depression” label.
Bipolar disorders matter in the differential
A history of manic or hypomanic episodes changes the diagnostic picture and treatment implications. Periods of unusually elevated or irritable mood, markedly reduced need for sleep, increased activity, pressured speech, racing thoughts, or risky behavior warrant careful clinical assessment rather than assuming that all mood symptoms represent unipolar depression with anxiety.
Medical conditions and substances can contribute
Palpitations, tremor, breathlessness, sleep disruption, fatigue, agitation, cognitive changes, and low energy can also occur with medical conditions, medication effects, withdrawal states, stimulant use, alcohol or other substances, and sleep disorders. Online symptom matching cannot safely rule those possibilities in or out. New, severe, atypical, rapidly changing, or medically concerning symptoms deserve appropriate medical evaluation.
How Clinicians Assess Anxiety and Depression Together
Assessment starts by separating symptoms from diagnoses. The American Psychiatric Association explains that DSM diagnostic criteria are designed for trained professionals using clinical judgment and include duration, exclusions, differential diagnosis, and comorbidity. WHO’s ICD-11 CDDR likewise provides clinical diagnostic requirements rather than a checklist for self-diagnosis.
The timeline
A useful assessment reconstructs the sequence: when anxiety first became persistent; when low mood or loss of interest appeared; whether panic, avoidance, social fear, generalized worry, or another anxiety pattern came first; whether depression followed a period of functional restriction; and whether symptoms emerged together after a major stressor. A timeline can reveal clinically relevant relationships without pretending to prove causation.
Severity, impairment, and safety
Clinicians ask how symptoms affect sleep, self-care, work, study, parenting, relationships, movement, finances, and social life. They also assess hopelessness, suicidal thoughts or behavior, self-harm, substance use, and the person’s ability to remain safe. Comorbidity can increase burden, but risk assessment depends on the individual rather than on a label alone.
Screening is not diagnosis
Questionnaires can estimate symptom severity or identify people who may benefit from further assessment. They cannot establish a formal diagnosis by themselves. APA’s DSM-5-TR assessment-measures resource includes disorder-specific severity measures, illustrating the distinction between measurement and clinical diagnosis. A high anxiety or depression score should be interpreted in context, including medical, substance-related, developmental, and psychiatric differentials.
For the assessment process in the anxiety cluster, see How Is Anxiety Diagnosed? Assessment, History, and Differential Diagnosis.
Why Comorbidity Can Matter Clinically
When anxiety and depressive disorders co-occur, the person may face several maintaining systems at once: avoidance can reduce exposure to rewarding activity; low motivation can make exposure or behavioral change harder to initiate; poor sleep can intensify both threat sensitivity and mood symptoms; and reduced functioning can generate fresh stress. The treatment plan therefore needs to identify what is driving current disability rather than simply adding two generic treatment packages together.
In the NESDA program, Ter Meulen and colleagues reported greater severity, chronicity, impairment, and multimorbidity in comorbid cases than in single-disorder cases. That finding supports careful clinical attention to comorbidity, while the observational design limits causal conclusions.
Comorbidity also matters because apparent treatment “resistance” can sometimes reflect an unrecognized second problem. A person receiving depression-focused care may still be constrained by untreated panic-related avoidance or social fear; someone receiving anxiety-focused care may have a depressive syndrome that limits energy, hope, and engagement. Reassessment is important when progress stalls.
Treatment When Anxiety and Depression Co-Occur
There is no universal rule that anxiety must always be treated first or that depression must always be treated first. The best sequence depends on the specific diagnoses, severity, safety, functional impairment, temporal sequence, prior treatment response, medical context, feasibility, and the person’s preferences.
This is reflected directly in NICE depression guidance: when depression is accompanied by anxiety symptoms, treating the depression is usually the first priority; when a person has an anxiety disorder plus comorbid depression or depressive symptoms, NICE advises consulting the relevant anxiety guideline and considering treatment of the anxiety disorder first. NICE guidance for GAD and panic disorder similarly recommends identifying the primary problem collaboratively and considering which condition is more severe and which treatment is more likely to improve overall functioning.
Psychotherapy
Cognitive behavioral therapies have strong evidence across depressive and many anxiety disorders, but the active procedures are not identical for every diagnosis. Exposure is central for many fear-based disorders; interoceptive exposure is particularly relevant to panic; behavioral activation is prominent in depression; social-anxiety work may target self-focused attention, feared evaluation, and safety behaviors; GAD treatment may emphasize worry processes and uncertainty. The existence of a shared CBT family does not erase disorder-specific techniques.
Transdiagnostic psychological treatments deliberately target processes shared across anxiety and depression. A 2023 meta-analysis by Cuijpers and colleagues included 45 randomized trials with 5,530 participants and found that transdiagnostic treatments were probably effective in the short term, with comparable effects on anxiety and depression outcomes. Heterogeneity was high and long-term evidence was thinner, so the finding supports transdiagnostic treatment as an evidence-based option rather than proving that one protocol is sufficient for every comorbid presentation.
Medication
Some antidepressant medications, including several SSRIs and SNRIs, are used for depressive disorders and for particular anxiety disorders. NIMH’s GAD resource notes that SSRIs and SNRIs are commonly used for both depression and GAD. That overlap can be useful when conditions co-occur, but indications, dosing, adverse effects, interactions, onset of benefit, discontinuation effects, and monitoring requirements differ across medicines and people.
Medication choice is therefore a clinical decision, not a search for the drug that treats the word “anxiety” plus the word “depression.” A prescriber needs the actual diagnoses, current medications and substances, medical history, prior responses, pregnancy considerations where relevant, bipolar-spectrum history, suicide risk, and patient preferences.
Integrated treatment versus sequential treatment
Some people benefit from an integrated plan that addresses both symptom domains from the start. Others benefit from prioritizing the problem that is currently most severe, risky, or functionally limiting, while monitoring the second condition. A clear formulation prevents “treat both” from becoming a vague promise and turns it into specific targets: panic attacks, avoidance, generalized worry, sleep, behavioral withdrawal, anhedonia, rumination, or another maintaining process.
What Can Help While You Are Seeking Assessment or Treatment?
Self-management can support care when it is used as support rather than as a substitute for assessment. A regular sleep-wake schedule, gradual return to meaningful activity, physical movement appropriate to health status, regular meals, reduced substance-related destabilization, and staying connected with trusted people can reduce some maintaining pressures. The aim is not to “think positively”; it is to rebuild predictable rhythms and access to reinforcement while reducing patterns that keep fear or withdrawal in control.
If avoidance has become extensive, abrupt self-directed exposure can be counterproductive when it is poorly planned or medically inappropriate. Evidence-based exposure is structured around the specific fear pattern and learning goals. If depression is severe, basic activation may need to begin with very small, realistic actions. Treatment should match the actual problem rather than forcing every person into the same self-help sequence.
Keeping a brief timeline can also help a clinical visit: when symptoms began, what changed first, what situations trigger anxiety, what activities have been lost, how sleep has changed, what medicines or substances are involved, what has helped before, and whether there are periods of unusually elevated mood or reduced need for sleep. This information is often more useful than arriving with a self-assigned diagnostic label.
When Urgent Help Matters
Depression can include thoughts of death or suicide, and severe anxiety can coexist with acute risk. WHO and NIMH both identify suicide risk as clinically important in depression. If you are in immediate danger, have an imminent plan to harm yourself or someone else, cannot remain safe, or are experiencing a potentially serious medical emergency, contact your local emergency service or crisis service now.
Urgent medical evaluation is also appropriate when symptoms such as chest pain, severe shortness of breath, fainting, new neurological deficits, severe confusion, or other acute physical signs could represent a medical emergency. Anxiety can produce intense physical symptoms, but symptom resemblance is not enough to rule out a medical cause online.
Frequently Asked Questions
Can you have anxiety and depression at the same time?
Yes. Anxiety symptoms and depressive symptoms can occur together, and a person can meet criteria for an anxiety disorder and a depressive disorder at the same time. Each diagnosis still requires its own clinical assessment.
Why do anxiety and depression so often occur together?
They share some broad vulnerabilities, including negative emotionality and partially overlapping genetic liability, and they can be connected through processes such as uncertainty, repetitive negative thinking, avoidance, sleep disruption, stress, and functional loss. Longitudinal evidence also shows that each can increase risk for the other over time. No single pathway explains every case.
Which usually comes first, anxiety or depression?
There is no universal order. Anxiety often begins earlier in some cohorts and diagnostic groups, but longitudinal meta-analysis shows bidirectional prediction: anxiety can precede depression and depression can precede anxiety.
Can anxiety turn into depression?
Persistent anxiety can contribute to later depression in some people through direct and indirect pathways, including avoidance, exhaustion, sleep disruption, social restriction, and loss of rewarding activity. It does not inevitably “turn into” depression, and shared risk factors can also explain why both develop.
Can depression cause anxiety?
Depression can precede later anxiety. Reduced functioning, uncertainty, practical stress, loss of confidence, and concern about recovery can increase threat anticipation. The relationship remains probabilistic rather than a one-way causal rule.
Are anxiety and depression one diagnosis?
No. Anxiety disorders and depressive disorders occupy distinct diagnostic territories. ICD-11 also includes Mixed depressive and anxiety disorder for a specific mixed presentation, but that diagnosis is not a synonym for having two separate disorders or for ordinary anxious and depressed feelings.
Can a GAD-7 or PHQ-9 score diagnose both conditions?
No. Screening and symptom-severity questionnaires can identify elevated symptoms and help monitor change, but a score does not establish a formal diagnosis or resolve differential diagnosis.
Can one treatment help both anxiety and depression?
Sometimes. Some psychotherapies and antidepressant medications have evidence across both domains, and transdiagnostic therapies can improve anxiety and depression. Treatment still needs to account for the specific disorders and mechanisms present, because disorder-specific interventions may remain necessary.
Does comorbidity mean the condition is more severe?
Comorbid groups often show greater average symptom burden and impairment in clinical research, but an individual’s severity cannot be inferred from the word “comorbid.” Severity, functioning, safety, chronicity, and treatment needs must be assessed directly.
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