Causes of Anxiety disorders

People with anxiety try to make others happy and feel bad when they don’t do their tasks. They are also cautious and pay attention to the details. Anxiety is the result of a combination of several factors

Genetic predisposition

Some people who experience anxiety may have a genetic predisposition toward anxiety than the others
Some people develop panic attacks, and some people couldn’t have panic attacks in any circumstance. But, if you have a parent or relative suffering from anxiety doesn’t mean you will develop anxiety. 
We all born with some variation of innate tendencies, if you have Panic attacks, this is one of yours.

Personality traits

Research suggests that children with particular characteristics are more likely to develop anxiety than the others
Some of the traits are: 
Children who are easily concerned, inhibited, shy or lack of self-esteem. 
They tend to develop anxiety as a child, during adolescence or as adults. Also, they may have grown up in an atmosphere which failed to teach them that the world is a safe place and they can pursue their happiness.
Maybe there was an early death in their family, their parents got a divorce or were alcoholic. Perhaps parents were anxious themselves and overprotective in response to their anxiety disorder.
Response to the challenge of adulthood
When they experience a period of high stress and stressful changes such as:
Feeling trapped in a bad job or relationship, change in living arrangements. The death of someone they love, buying or selling home, having babies, etc.
A situation that had a cumulative stressful effect on the person to the point when it is hard to cope with them all. 
People begin to develop panic attacks in their twenties or thirties.
In the years of establishing an independent life themselves are most likely to experience this kind of changes.
These factors have one thing in common:
They are not under your control. 
They are developmental events which happen to some people.
The factors which have caused your panic attacks are not something you could have controlled
So there is no reason to feel guilty, ashamed, or apologetic about having panic attacks. They are not the result of living poorly, making bad decisions or of being “stupid,” or acting like a coward.
It is your problem, not your fault.
Everyone is different. Often, it is a combination of factors that cause you to experience anxiety. You can’t also always identify the circumstances or factors which cause anxiety.
And the most important thing is to recognize the symptoms and to seek advice and help because it is a very treatable problem.