@munchie, I really don't think anyone doctor or patient really knows the answer to your question. I've had two occurrences of PMR with 6 years in between them. The first one lasted 3 and half years before I could taper off of the 20 mg prednisone used at the start to control the pain and inflammation. The second one last 1 and half years before I could taper off of the same 20 mg dosage. I'm sure others have similar experiences. My Mayo rheumatologist also told me that the disease/condition stays with you but just is under control or in remission.

Here's some more info I found that kind of infers the same ... "However, they do not cure the disease. The low-dose corticosteroids used in PMR are almost certainly ineffective in the prevention of vasculitis progression. It has been found that remission of PMR seemed to be achieved with a 15-mg/d dose of prednisone for most patients. Jun 20, 2012" -- Polymyalgia Rheumatica: A Severe, Self-Limiting Disease: https://www.uspharmacist.com/article/polymyalgia-rheumatica-a-severe-self-limiting-disease

@kmeikle1 - The 2 year average comes from the articles similar to the one above from 2012 that contains this excerpt - "Approximately 50% to 75% of patients can discontinue corticosteroid therapy after 2 years of treatment, and patients with PMR should be monitored regularly and carefully for symptoms and signs suggestive of GCA development.11".

Definition of remission and relapse in polymyalgia rheumatica: data from a literature search compared with a Delphi-based expert consensus: https://ard.bmj.com/content/70/3/447