Sorry, I know I'm a Guest and only stumbled onto whilst checking out something else, but it's a topic close to our hearts.

It's not a disease, but it is believed to be hereditary. If you have siblings or children over 40 tell them to get checked out regularly as well. If caught early there is no problem. In UK checks are free, and throughout most of Europe, USA, Canada, Aussie etc. opthalmologists do pressure tests as a matter of routine.