[Kobal2]

Many of Abysia's mages start old, as indicated by that white, bearded face on their stat page. They also have fire magic, which shortens their lifespans further, and make the advanced states of old age come even sooner than for average humans.
So come late winter, unless you have Growth scales (and even worse if you have Death scales), they're going to catch a cold and lose an arm here, a mind there.

The common cold is right nasty in the Dominionverse :]

Besides Growth scales, the only way to avoid this is to have them cast spells to go back to youth (there's a Blood spell that does that), or forge them some Boots of Youth (which won't make them grow any younger, but will freeze their age and prevent winter afflictions). Both options are a bit too expensive to use on *all* of your mages, but they're worth it to preserve people with nice random picks, or ones you empowered.