POS0962 DIFFERENCE IN CLINICAL AND SEROLOGICAL CHARACTERISTICS OF ADULT ONSET STILL’S DISEASE BETWEEN ELDERLY-ONSET AND YOUNG-ONSET PATIENTS

Background Adult-Onset Still’s Disease (AOSD) is a systemic autoinflammatory disease of unknown etiology characterized by fever, skin rash, and arthritis. AOSD generally develops in young adults, with the mean age at onset 30 to 40 years old female dominant. However, distribution diagnosis has recently shifted towards older patients AOSD, as well other rheumatic musculoskeletal diseases. The clinical manifestations elderly-onset have not been yet, understanding characteristics elderly essential for appropriate management. Objectives To clarify AOSD. Methods We reviewed consecutive who had visited Keio University Hospital from 2012 2022 retrospectively. divided them into two groups according age. was defined ≥ 65 years. compared their characteristics, laboratory findings, image examination data. All statistical analyses were performed using JMP 15 (SAS Institute Inc, Cary, NC, USA). Results included 103 analysis. Among them, 20 (19%) developed or categorized elderly-onset. median young-onset 78 47 years, proportion 75% 82%, respectively. significantly increased 2000s, highest 30% after 2010s (Figure 1). In group, frequency serositis, interstitial lung disease, Pouchot Score higher than young–onset group (70% vs 8%, p<0.001; 26% 6%, p=0.009; 7 6, p=0.014, respectively). On another front, typical sore throat, splenomegaly less frequent (40% 74%, p=0.039; 40% vs. 67%, p=0.026; 21% 50%, p=0.025, respectively, Table duration hospitalization longer (48 days, p=0.03), yearly incidence (0.86/year 0.24/year, p<0.001). Hospitalization flare recurrence comparable between (44% p=0.632), while due infectious complications more frequently observed group. 1. Clinical Younger-onset (n=83) Elderly-onset (n=20) p Value Age (years ) <0.001* Sex (Female %) 62(75%) 14(82%) 0.501 Death (n (%)) 4(4.8%) 2(10.0%) 0.330 Observation period （year） 7.8(3.4-14.7 3.5(1.9-5.8 0.008* Length (Day 27(0, 56 79(36.5, 169.5 <0.001 Characteristics High fever (>39℃) 46(92%) 17(85%) 0.399 Pharyngalgia 53(67% 8(40% 0.026* Typical rash 57(74% 0.004* Myalgia 30(65%) 8(44%) 0.128 Arthralgia 72(87%) 19(95%) 0.302 Lymphadenopathy 58(88%) 14(70%) 0.058 Hepatomegaly 53(94.6%) 16(80.0%) 0.073 Splenomegaly 33(50% 4(21% 0.025* Serositis 6(8% 14(70% Pleuritis 14(70.0% Pericarditis 7(35% 0.003* Interstitial 4(6% 5(26% 0.009* White blood cell (/µL) 15450 (11700-19335) 16250 (10978-19958) 0.838 CRP (mg/dL) 15.8(7.9-19.7) 14.1(7.1-24.0) 0.620 Ferritin (ng/mL) 3373 (990-9020) 4565 (1306-13640) 0.747 score 6(4-6 7(5-7.8 0.013* Figure Trends Conclusion increasing recent Patients characteristic features comparison those Attention should be made Reference [1]Maruyama A, Kokuzawa, Yamauchi Y, et al. creatures Adult-onset disease. Modern Rheumatology, 2021;31(4):862–868 Acknowledgements: NIL. Disclosure Interests None Declared.