Anxiety disorders are among the most common of all psychiatric disorders. The global current prevalence for anxiety disorders is 7.3 %, suggesting that 1 in 14 people around the world at any given time has an anxiety disorder and 1 in 9(11.6 %) will experience an anxiety disorder in a given year (Baxter et al. 2013 ). Per year, the estimated cost (directly and indirectly) of anxiety disorders in the United States alone is over $42 billion (Greenberg et al. 1999 ). More than 50 % of these expenses are due to clinical care stemming from misdiagnosis, inadequate treatment, and emergency care (including psychiatric and nonpsychiatric hospitalization), the net effect of which is reduced productivity and absenteeism from theworkplace (Lepine 2002 ).
Anxiety disorders have a substantial, negative impact on individuals. Effects are seen not only in emotional and physical health but also through impairments ineducational, social, and occupational functioning as well as in overall quality of life (Olatunji et al. 2007 ). A review of over 1,000 subjects aged 16–25 with anxiety disorders found that those with anxiety disorders had a 5.85 times higher rate ofsuicide attempts (Boden et al. 2007 ) than those without an anxiety disorder. There are numerous risk factors implicated in the development of anxiety disorders, including low self-esteem, family history of depression, female sex, childhood sexual abuse, White race, years of education, number of traumatic experiences, and disturbed family environment (Blanco et al. 2014 ).
Anxiety disorders are characterized by excessive fear and the associated behavioral disturbances. Although the experience of some degree of anxiety is normal inlife, anxiety disorders are defined by both the severity and duration of symptoms. In anxiety disorders, the fear is excessive and, in general, lasts for 6 months or longer (APA 2013 ).The National Comorbidity Survey found that lifetime prevalence rates for each anxiety disorder were lower in males compared to females: panic disorder (PD)(2.0 % in males vs. 5.0 % females), specifi c phobia (6.7 % vs. 15.7 %), social anxietydisorder (SAD) (11.1 % vs. 15.5 %), and generalized anxiety disorder (GAD)(3.6 % vs. 6.6 %) (McLean et al. 2011 ). Because each of the anxiety disorders occur approximately half as commonly in men (APA 2013 ; Blanco et al. 2014 ; Mondinet al. 2013 ; Kessler et al. 2005a ), and because the anxiety disorders may differentially impact men (Grant and Potenza 2007 ), the goal of this chapter is to discuss the role of gender in our understanding and treating of anxiety disorders. Specifically, we will be discussing the impact of gender on social anxiety disorder, panic disorder, generalized anxiety disorder, and phobias, with particular emphasis on their epidemiology, etiology, clinical presentation, current treatment guidelines, and future directions for research.