Suffering From Arthritis, Relieved Of Pain When Went To A Place Higher In Altitude. Opinion?

How is it that the higher you go in altitude the less pain you have from arthritis , including it eliminating any pain at all? I live in south Louisiana and spend about 23 out of 24 hours a day in bed on ice or heat, paying people to do everything for me and I just went to Branson, MO,,,,,,,,,,,, I actually drove the entire way, at first with a TENS UNIT on and pain medicine, only to find that once in Branson, MO, I awoke with zero pain.......climbed a strenuous hike up a mountain and rock climbing for 3 1/2 hours and still had no pain.....I had no pain for a total of 19 hours until I reached Arkadelphia or thereabouts, the closer I got to Louisiana, the more I felt like I needed a to be shot to be put out of my misery. I could barely sit. I was going out of my mind in pain! Physical and emotional! And now that I am back in Lafayette, I have been avoiding even washing a load of laundry and even considering paying someone to do everything, which is the way I was doing before the trip. HOW AND WHY DOES ALTITUDE AFFECT THE PAIN CAUSED BY ARTHRITIS??? Thanks, Laureen Olson