I have trouble believing that bipolar can be outgrown. Without actually reading the actual study, I have to wonder if they followed many individuals doing a longitudinal study or did they evaluate a spectrum of people across ages. How can you know if people "grow out of it" if you don't follow them through decades? I know I had depression and what I think was hypomania as a child, starting in 2nd grade. Between the ages of 18 to 37, my life was quiet and stable although looking back I can see short periods of hypomania. When faced with a tragedy, the death of my only child, Serena, depression followed by hypomania returned full force. I believe I have had bipolar all my life but was lucky to have been in almost a full remission for many years. If someone had asked me questions about bipolar symptoms during those years I would have said that I was fine. (I had been diagnosed with depression as a child, but not bipolar until I was 48.)