Incidence of rheumatoid arthritis, psoriatic arthritis and polymyalgia rheumatica in an inland area of central Italy: results of the CAMPO-RHE study

Objective: The aim of the CAMPO-RHE study was to determine the incidence of rheumatoid arthritis (RA), psoriatic arthritis (PsA) and polymyalgia rheumatica (PMR) in patients attending a rheumatologic outpatient’s clinic of a new institution in Campobasso, Italy. Methods: Campobasso is a small town of approximately 50,000 inhabitants located in the inland territory of central Italy (Molise), and Public Health is managed from a single health authority. In Italy, all citizens are registered with a National Health System of General Practitioner (GP) Physicians. Between the 1stof June 2014 and the 31stof May 2016, all consecutive adult patients, sent by a GP, of Campobasso with any diagnosis of musculoskeletal symptoms/signs/complaints were evaluated in a single rheumatology outpatient clinic of our Academic Unit. The clinic represents the first and unique reference for GPs about rheumatic diseases in the territory. Subjects were classified using the 2010 EULAR criteria for RA, the CASPAR criteria for PsA and the 2012 ACR classification criteria for PMR. Results: 1003 adult patients, sent by GPs, with articular or musculoskeletal complaints visited our clinic. Of these, 409 inhabitants of the municipality of Campobasso were evaluated for the study. During the 2-year study period we diagnosed 18, 19 and 12 new cases of RA, PsA and PMR respectively, with a new incident cases rate of 21.4, 22.59 and 27.43/100,000/year on the population at risk. Conclusion: The results of our study could contribute to better define the incidence of these rheumatic diseases classified with the new classification criteria.