Objective: Polymyalgia rheumatica (PMR) is a common rheumatologic disease in the elderly population. Studies on the relationship between PMR and cancer have yielded mixed results and have been limited by multiple factors. This study examined the association between PMR and development of cancer in a community cohort.
Methods: A population-based cohort of 359 patients with PMR diagnosed between 1/1/1970 and 12/31/1999 and followed to 12/31/2013 was assembled along with a comparison cohort of 357 subjects. Records of the PMR and comparator subjects were reviewed for details concerning diagnosis of cancer. The cumulative incidence of malignancy in patients with and without PMR, adjusted for the competing risk of death, was estimated and compared using methods of Gray. Cox proportional hazards models were used to assess the trends in malignancy over time.
Results: There was no significant difference in the prevalence of malignancy prior to PMR incidence date/index date between the two groups with prior malignancies in 41 (11%) of patients with PMR, and 50 (14%) of non-PMR subjects (p-value=0.31). As well, there was no difference in the cumulative incidence of malignancy at 10 years following PMR incidence between patients with PMR and non-PMR subjects (cumulative incidence at 10 years ± SE: PMR 13.8 ± 2.0, control 13.1 ± 2.0; p-value=0.89).
Conclusion: There is no increased risk of malignancy in patients who are diagnosed with PMR when compared to subjects without PMR in this population-based cohort.
Keywords: cancer; polymyalgia rheumatica.