Aetiology

Aetiology of PMR is unknown (1).

The disease can be regarded as one extremity of a disease spectrum with giant cell arteritis at the opposite pole. In effect, giant cell arteritis represents the basic pathological lesion underlying temporal arteritis and polymyalgia rheumatica.

Possible susceptibility factors for polymyalgia rheumatica include:

• genetic causes
• environmental factors
• although rare, familial aggregation has been described (1)

The occurrence and severity of polymyalgia rheumatica is associated with HLA-DRB1*04 and DRB1*01 alleles (2).

Reference:

• (1) Kermani TA, Warrington KJ.Polymyalgia rheumatica. Lancet. 2013;381(9860):63-72
• (2) Cutolo M, Cimmino MA, Sulli A. Polymyalgia rheumatica vs. late-onset rheumatoid arthritis.  Rheumatology 2009; 48(2):93-95