Bipolar disorder can affect absolutely anyone. There is always a fine line between a person being well or ill. I think we all experience low moods (such as when a relationship breaks up or when we lose a loved one) or extreme highs too. Its when these High or Lows become extreme in response to life events that they become a disorder, or when the lows become depressive or the highs make you do things you would not normally do when your mood is norml that it becomes an issue.
Bipolar is often inherited. A common trigger is a relationship which creates insecurity.
it doesn't
Some people with bipolar find that their moods vary with the seasons, having depressive episodes in winter and manic episodes in summer. Also, stress can affect it.
No.
Bipolar does run in families, though it doesn't affect everyone.
No
Bipolar disorder is not a disorder that comes in stages. If you are referring to how "bipolar" this person is, well, they are bipolar. So really, how moody they are depends on the day.
Yes, but diagnosis is much more difficult the younger the person is. It can easily be confused with many other things.
No not really. You can tell a bipolar person from another. Bipolar persons will go through many mood swings. The person can feel happy about something one instant and then the next they could be sad or depressed. I would know as my mother is bipolar.
It doesn't. Get lost!
no known effect
can it? yes, dramatically.