Hello, yes it definitely does affect the various lung illnesses/conditions.
To start off with, think about what happens when a person travels or is in higher altitude, like upon a mountain, where personally I'd never have been one to climb the Annapurna Mountain Range in Nepal, the very idea of even being near anything like that now feels like a boa constrictor has me by the neck.
I think what is important, is the relative air humidity, this means the ratio of water/moisture/humidity in comparison or relation to the temperature.
This very thing is the reason plants either wo'nt grow or very grow little or slow, or else go nuts and become huge like in the tropics, there in the tropics it is because it is very hot but humid at the same time.
So in one country where it is always cold but humid too, the plants will not grow too well, and the combination of humidity and temperature will not be a positive for people with breathing problems caused by lung illnesses, however, in a European country where it is in summer quite hot but the humidity is far higher in relation to actual temperature, it may feel more uncomfortable than it would in an even hotter country, because the heat would balance out the moisture.
I think though, the only way to know, is to visit different places but for most people that's not an option to be had.
My own idea is that a place with a steady temperature is the best, so no fluctuations, an that would be where the temperatures do not decrease in winter time, like on the Azores islands, even in summer it doesn't get too hot there but in winter it doesn't get too cold either.
All of these matters are different for each individual, personally, I like a slightly higher temperature during summer than is the case on the Azores, where it doesn't get much hotter than 25 degrees Celsius from what I've read about it.
I think some of the Canary Islands might have good temperatures too, but they see higher temperatures, these varying inland according to altitudes, etc.
I want to visit Wales, my great grandmother came from Wales, but, when looking at Google Street View, all the pictures showed only rain drenched panoramas and streets/fields, so I was wondering how the climate there would affect me.
There are a number of people writing ion here who live in Wales, I'd like to hear from them what they think it does to them, living there, whether the fresher air compensates for the abundance of rainfall and lack of sun or is it all in all just about the same s it is in other parts of the UK, such as in England.
Anyhow, talking of boa constrictors, as an aside I had this dream or rather almost nightmare the other night, I suddenly found myself with my grandson in an enclosure full of wild cats, lions, and in that very instant of fear, really for your life (mine and his) I had to act and I was angry and ready to die and thought I would be too, but I punched one lion that approached on the nose in anger protecting ma-boy and managed to get us out of there over the fence before the other lions had time to think over what I'd just done (had the audacity to do), as the lion I punched on the nose piddled right off sharp.