A couple of months back I posted a query re experiencing shortness of breath after six months on goserelin + zytiga, wondering how this might impact me when I joined my youngest Son (32) for a couple of weeks hiking in Yellowstone and Grand Teton.
There were many, many replies and lots of advice, even including the possibility of taking along small bottles of oxygen, that I did in fact see for sale in lots of places in both parks!!
Having made it back alive and in view of the interest in that original post, I thought I would set out some stuff I learned along the way:
- I have some other lung issues (historic scarring or possible progressive deterioration - can't tell from the x-rays, so I'm monitoring it closely), but the short answer is that careful testing showed that prior to the trip I dropped around 25% oxygen handling capacity in the first six months on Zytiga, and that all of this drop was due to a reduction in my blood's oxygen carrying capacity - if anything, my lungs' physical capacity increased slightly during this same period.
- During two weeks in the US at elevations around 2400m (cf. where I live in Melbourne which is just about at sea level), I noticed my at-rest pulse went up by about 10bps to the mid 70s, but that when I hiked or walked up almost any incline at all, my pulse raced quickly up through the 90s to around 120 and above. That said, I didn't feel dizzy or too bad.... and I wasn't even slightly tempted to increase my carbon footprint by buying an aluminium cylinder of oxygen! I'll keep that for a later stage, at which time I'm sure my climate concerns will be quickly junked!
- During the second week I did start to feel tired in the afternoons and began to feel like I was down the end of a long pipe when I was driving... given I found that Americans drive on the wrong side of the road and at ridiculously high speeds, on pretty shitty roads, this became a rather interesting part of the trip (my Son, like many inner city-dwelling millennials, hasn't yet been possessed of the need to get a driving license, so there was no back up here!!).
- These slightly weird sensations reduced when we got back into Salt Lake City (1280m ASL) and were completely gone by the time we landed in LA. And the good news when I landed in Melbourne, is that I was 3KG lighter and my resting pulse was back in the sixties.... all that extra oxygen feels great!!
I have travelled all over the US many times for business, but this is the first time I have been to these two parks, and I guess I finally have to admit that you guys really do have it over Australia in terms of scenery - just so much water everywhere, and the animals are truly spectacular.... shame about all the tourists though!
Anyway... my take is that Zytiga definitely knocks your oxygen-handling capacity around, but that providing your underlying cardiovascular system is in reasonable nick, you'll survive it... it's easy to let it hold you back, but I saw no evidence that it predisposed me to sudden deterioration. Instead, it seemed to me that after a week or so, the body still increased its oxygen capacity in response to reduced atmospheric oxygen levels, as would normally be expected.
I trust this provides some reassurance to others who notice their breathing being affected.
Stuart
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