Abstract Background/Aims Seasonal variations in inflammatory rheumatic diseases have been well-described for many autoimmune diseases; however, there is no data for adult-onset Still’s disease (AOSD) in the literature. Our aim with this study is to evaluate whether there is a seasonal distribution of AOSD occurrence and possibly investigate any relationship between this distribution and the course of the disease. Methods A total of 62 patients, who were diagnosed with AOSD according to the Yamaguchi criteria in our clinic, were included in this study. The clinical symptoms of the patients until the first diagnosis, the season and month in which the symptoms began, demographics (age and gender), laboratory findings at diagnosis, and disease course during follow-up were recorded. The relationship between the months that the patients’ symptoms started and the clinical course was analysed. Results 80.6% of the patients were female with calculated mean age at diagnosis of 40.32 + 14.88 years. Fever (98.4%), rash (77.4%), arthritis (67.7%) and sore throat (54.4%) were the most common reported clinical findings at diagnosis. Disease courses were as follows: monophasic in 35, polyphasic in 18, and chronic persistent in 5. The total follow-up period was 53.5 + 57.15 months for the entire cohort. Macrophage activation syndrome (MAS) developed in 6 patients either during initial or follow-up period. Two of these patients died due to multiorgan failure. AOSD onset was most commonly seen in March (19.4%), April (12.9%) and December (12.9%), whereas it was found to be rare in August and September, with 1.6% for each. Among all admissions, AOSD seems to occur most frequently in spring (40.3%) and least frequently in summer times (11%). No significant relationship was found between the seasonal distribution and disease course (p:0.635). MAS cases developed in March (2), May (2) and December (2). Conclusion There are evidence that show seasonal distribution in some rheumatic diseases: either in occurence and/or relapse. Thus, seasonal variation in humidity, temperature along with other reasons such as increased infections, can be triggering factors. Our study is the first that demonstrates the seasonal distribution in AOSD and investigates any relationship with disease courses. Disclosure R. Yildirim: None. M. Dinler: None. B. Uludogan: None. N. Yasar Bilge: None. T. Kasifoglu: None.
Yildirim et al. (Wed,) studied this question.