At least 6 million Americans suffer from panic attacks and panic disorder both conditions classified as anxiety disorders. According to the Anxiety and Depression Association of America (ADAA), about 2-3% of Americans experience panic disorder in a given year and it is twice as common in women as in men. Panic disorder typically affects individuals when they’re in their 20s but is also seen in young children, adolescents, and older adults.
The cognitive effects of anxiety may include thoughts about suspected dangers, such as fear of dying. "You may ... fear that the chest pains are a deadly heart attack or that the shooting pains in your head are the result of a tumor or an aneurysm. You feel an intense fear when you think of dying, or you may think of it more often than normal, or can't get it out of your mind."
Secondly, the psychobiological conceptualization of panic disorder emphasizes the influence of psychological factors (Meuret, White, Ritz, Roth, Hofmann, & Brown, 2006). This psychological factor refers to a fear of bodily sensations, or a certain set of beliefs that lead individuals to be especially afraid of physical symptoms, such as believing that a racing heart could mean heart disease. Sometimes this is discussed as anxiety sensitivity or a belief that anxiety is harmful. Again, having the belief that physical symptoms are harmful may increase the likelihood of experiencing a panic attack, but it does not make having a panic attack inevitable. Instead, panic attacks can seem abnormal if they occur at the wrong time, when there is no real reason to be afraid. It is important to consider, however, that anxiety can also be adaptive or helpful in contexts where there is true threat.
Genetics and family history (e.g., parental anxiety) may predispose an individual for an increased risk of an anxiety disorder, but generally external stimuli will trigger its onset or exacerbation. Genetic differences account for about 43% of variance in panic disorder and 28% in generalized anxiety disorder. Although single genes are neither necessary nor sufficient for anxiety by themselves, several gene polymorphisms have been found to correlate with anxiety: PLXNA2, SERT, CRH, COMT and BDNF. Several of these genes influence neurotransmitters (such as serotonin and norepinephrine) and hormones (such as cortisol) which are implicated in anxiety. The epigenetic signature of at least one of these genes BDNF has also been associated with anxiety and specific patterns of neural activity.
Separation anxiety disorder: Separation anxiety is often thought of as something that only children deal with; however, adults can also be diagnosed with separation anxiety disorder. People who have separation anxiety disorder have fears about being parted from people to whom they are attached. They often worry that some sort of harm or something untoward will happen to their attachment figures while they are separated. This fear leads them to avoid being separated from their attachment figures and to avoid being alone. People with separation anxiety may have nightmares about being separated from attachment figures or experience physical symptoms when separation occurs or is anticipated.