Diagnosed With RA, Taking Steroids. Knee Stiffness And Swelling. How Long Will I Be Able To Survive?

hi, i m 45 yrs old mother diagnosed with ra last year. Initial 3 months i was on steroids but i m taking hcqs every night and those vitamin and mineral supplements . i am very much active doing walking+ stretching for 45 minutes daily my left knee is the most affected part from the begining . i feel stiffness occasionally and there is little swelling also on the side of the both knees. my doctor always motivates me by saying i m responding well but i worried little if not much about my health and how long i will be able to survive with ra.