POS0547 METEOROLOGICAL VARIABLES HAVE DIFFERENT INFLUENCE ON CORE MEASURES OF DISEASE ACTIVITY IN PATIENTS WITH RHEUMATOID ARTHRITIS

Background: The notion that weather conditions may influence the symptoms and course of rheumatic and musculoskeletal diseases goes back to ancient times. However, despite the seemingly obvious relationship, previous studies assessing how meteorological variables affect pain and disease activity have yielded contradictory results. Objectives: To evaluate whether meteorological variables influence disease activity in patients with rheumatoid arthritis (RA). Methods: We assessed correlations between clinical measures of disease activity (pain, patient global assessment [PGA], tender- and swollen 28 joint counts [TJC and SJC]) and individual meteorological variables: temperature (temp.), effective (eff.) temperature, saturation vapor pressure (SVP), absolute humidity (AH), relative humidity (RH), dew point, vapor pressure (VP) and precipitation. Assessments documented in the Care for Rheumatoid Arthritis database of our institution were matched with these meteorological variables on a daily basis for a period of 12 years between 2005 and 2017 and analyzed utilizing generalized estimating equations. Patients with <5 visits in the study period, those with <1 visit/quarter or with no pain (VAS=0) in ≥3 consecutive visits and those living outside of the catchment area were excluded. Patients were grouped into remission or low (≤11) vs. moderate or high (>11) disease activity based on the simplified disease activity index (SDAI). Results: A total of 461 patients with an average disease duration at first visit of 5.7±7.4 years, average age of 55.3±14.5 years and a mean SDAI of 22.1±12.7 were analyzed. Among patients with moderate or high disease activity, higher temp./eff. temp. and SVP were associated with lower pain, TJC and SJC (Figure 1); on the contrary, higher RH was associated with higher pain and higher SJC. In those in remission or low disease activity, higher RH, AH, VP or dew point were associated with lower PGA. Higher precipitation was associated with lower SJC. Figure 1. Association of meteorological parameters and clinical measures of disease activity . PGA: patient’s global assessment, SDAI: simplified disease activity index, SJC: swollen joint count, TJC: tender joint count. * p≤ 0.05, ** p≤ 0.01, *** p≤ 0.001 Conclusion: In this large association study of meteorological parameters with RA, both temperature and humidity parameters were modestly inversely associated with pain, TJC and SJC. Disclosure of Interests: None declared