Anxiety Disorder Causes and Risk Factors

Genetic and Biological Factors

Anxiety disorders have a strong hereditary component, with heritability estimates ranging from 30% to 50%, meaning that genetic predisposition accounts for approximately one-third to one-half of the risk for developing these conditions, according to the American College of Physicians 1

The median age of onset for anxiety disorders is approximately 11 years, though specific disorders emerge during predictable developmental phases, as reported by the American Academy of Child and Adolescent Psychiatry 2
Separation anxiety typically onsets during preschool and early school-age years, social anxiety develops in later school-age and early adolescent years, and generalized anxiety, panic disorder, and agoraphobia typically onset in later adolescence and young adulthood, according to the American Academy of Child and Adolescent Psychiatry 2
Anxiety disorders increase in both frequency and severity during pregnancy and the postpartum period, affecting not only the mother but also the infant and family, as noted by the American College of Physicians 1
Behavioral inhibition, autonomic hyperreactivity, or negative affectivity in childhood may foreshadow later anxiety disorder development, as reported by the American Academy of Child and Adolescent Psychiatry 2

Stressful or traumatic exposures play important etiologic roles in anxiety disorder development, according to the American Academy of Child and Adolescent Psychiatry 2
Insecure attachment patterns contribute to anxiety disorder risk, as reported by the American Academy of Child and Adolescent Psychiatry 2
Parent and parenting factors influence the onset and development of anxiety disorders, according to the American Academy of Child and Adolescent Psychiatry 2

Before diagnosing a primary anxiety disorder, clinicians must rule out alternative medical causes including thyroid disease, cardiac disorders, respiratory conditions, and drug-related effects, as recommended by the American College of Physicians and the American Society of Clinical Oncology 1, 3
Hormone-secreting tumors can produce anxiety symptoms, as reported by the National Comprehensive Cancer Network 4
Certain medications, particularly bronchodilators, can induce anxiety, according to the National Comprehensive Cancer Network 4
Alcohol withdrawal causes anxiety symptoms, as noted by the American College of Physicians 1
Narcotic withdrawal produces anxiety, as reported by the National Comprehensive Cancer Network 4
Stimulant use (including caffeine and illicit substances) triggers anxiety, according to the American College of Physicians 1
Hyperthyroidism mimics anxiety disorder symptoms, as noted by the American College of Physicians 1
Unrelieved pain and other distressing physical symptoms can manifest as anxiety, as reported by the American College of Physicians and the American Society of Clinical Oncology 1, 3

Anxiety disorders are highly comorbid with each other, demonstrating both homotypic continuity (one anxiety disorder predicting another anxiety disorder) and heterotypic continuity (anxiety predicting other psychiatric conditions), as reported by the American Academy of Child and Adolescent Psychiatry 2
The estimated prevalence of anxiety disorders in patients with major depressive disorder is 56%, suggesting shared underlying vulnerability, according to the American College of Physicians 1
Anxiety disorders frequently co-occur with substance use disorders, posttraumatic stress disorder, bipolar disorder, ADHD, learning and language disorders, behavior disorders, obsessive-compulsive disorder, eating disorders, and personality disorders, as reported by the American Academy of Child and Adolescent Psychiatry 2
The presence of an anxiety disorder is significantly associated with at least one suicide attempt in large-scale epidemiologic studies, as noted by the American College of Physicians 1

There is a slight gender imbalance with a slightly higher prevalence among women (odds ratio: 1.5–2.2), as reported by the International College of Neuropsychopharmacology 5
Anxiety disorders increase in frequency and severity during pregnancy and the postpartum period specifically in women, as noted by the American College of Physicians 1