Honestly, pursue it as a hobby but don't try to make a career out of it. This is the worst hiring environment I've seen since the dotcom bust, and there are tens of thousands of fresh CS grads that are unemployed.
If you want to go to school because you're interested, then that's cool. But to think you can make a living out of it when you're 30 years older than the tens of thousands of kids that you're competing against... I really don't think it's worth it unless you want to form your own startup that is medical-related.
Thank you for your insight about the hiring environment! What are your thoughts about getting involved in an open-source project or something else to get some more experience?
definitely go for it, it's a great way to get recognition. However, it's a terrible way to learn because getting a mentor to teach you how to make changes will be very tough. But if you can, it's great because it's real work and real code changes.
I have mentored and been mentored and it's a tough process but necessary. It's what is stopping a lot of people learning a new profession later in life in my opinion, who would want to mentor an older person? I mentor young people with lots of energy and they are often very eager to learn.