Thats extremely doubtful.

Depression is one of the few illnesses that, just by its nature, exponentially grows in magnitude.  One of the ways it does this is its stigma.  (ex. A person suffering from depression will usually have guilt because of the stigma surrounding the illness as one of their symptoms-so reaching out regarding their illness will be exceptionally difficult.  Simultaneously: Others will not want to reach out to the victim because they do not understand the illness and realize instead the stigma, thus driving the victim even further into isolation.  Even JK Rowling cant break this.

It doesn't surprise me that she has issues by depression; in fact, psychological disorders are fairly commonplace in creative people.  It is not at all hard to find a famous writer, author, poet, actor, artist, comic, or musician with depression.-Likely because you will develop a complex that people do not understand you; and in the case of Jk Rowling, Robin Williams, and John Denver they really weren't.