In the US, outcomes for people with type 1 diabetes (autoimmune and insulin-dependent) really have not improved substantially against other countries. In many ways, we have regressed. I personally have type 1 diabetes and care is so much different abroad.
This is just one symptom of our malady within the US healthcare system: it is about profit and not about improving the health, livelihood, and longevity of the general population.
I naturalized as a citizen with universal healthcare over stuff like insulin prices, although this was not the primary reason. I studied healthcare systems for hundreds of hours to figure out where I would need to establish myself. If anyone wants help or advice regarding healthcare systems and/or citizenship matters, I am here to help. Check my email on my profile.