A Danish nationwide population-based cohort study estimated annual PMR incidence rates from 2003 to 2024 and described disease course — including late-onset GCA occurrence and prednisolone (PDN) treatment duration — in adults aged ≥50 identified across primary and secondary care using a novel record-linkage algorithm.
51,401 PMR patients were identified; age-standardised incidence was 112 per 100,000 (95% CI 110.8–112.8). Overall incidence declined 12% over the study period (primary care −53%, secondary care +30%). GCA occurred at 5.4 per 1,000 patient-years (median 68 days after PMR diagnosis). At 5 and 10 years, 28% and 22% of patients remained on PDN (median daily doses 4.1 mg and 5.5 mg, respectively).
- Algorithm-based case identification may introduce misclassification across healthcare sectors. - Observational design limits causal inference about treatment patterns and outcomes. - Reasons for the shift from primary to secondary care incidence are not fully explained.
Most late-onset GCA appears within the first year of PMR diagnosis, so heightened vigilance is warranted early. The high proportion of patients still on prednisolone at 5–10 years supports earlier consideration of steroid-sparing or concomitant therapies.
