Answer to Question 1
Prevalence rates for anxiety disorders are lower for individuals over 60 than those who are under 60, although there is some evidence that this rate may increase as individuals reach ages of 70 or 80 and encounter the inevitable fears of old age, disease and death. In addition it is relatively uncommon for an individual to develop an anxiety disorder later in life. Older adults diagnosed with anxiety disorder most likely developed the condition at an earlier age. The diagnostic process is also complicated by age. Some physical disorders associated with age, such as cardiovascular problems, have symptoms similar to some anxiety disorders. For example, hearing loss can lead one to behave in a way that looks like social avoidance. Now, if an elderly person has a physical trauma, such as a fall or a car accident, that leads her to go out less, should this be seen as a symptom of agoraphobia or a sensible precaution due to failing abilities?
Answer to Question 2
Lumpers are theorists who suggest that there should be no subdivisions of anxiety disorders. For them, anxiety is anxiety and the particular manner in which it manifests is not particularly relevant. These theorists believe it is quite likely there is one etiological model that can account for all forms of anxiety disorders, and variations are only a matter of individual differences and life experiences. Splitters, on the other hand, suggest that we need different diagnostic categories for several variations of anxiety disorders. For them, the differences seen in anxiety disorder are due to different etiologies and, likely, different treatments. Splitters believe diagnostic distinctions will guide the research and treatment of what, for them, are different diseases.
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