anxiety vs panic attack

anxiety

noun
  • An unpleasant state of mental uneasiness, nervousness, apprehension and obsession or concern about some uncertain event. 

  • An uneasy or distressing desire (for something). 

  • A state of restlessness and agitation, often accompanied by a distressing sense of oppression or tightness in the stomach. 

panic attack

noun
  • A sudden period of intense anxiety, mounting physiological arousal, fear, stomach problems and discomfort that are associated with a variety of somatic and cognitive symptoms. 

How often have the words anxiety and panic attack occurred in a corpus of books? (source: Google Ngram Viewer )