THU0283 DISTINCT CLINICAL FEATURES OF LATE–ONSET SYSTEMIC LUPUS ERYTHEMATOSUS AMONG MALAYSIAN MULTI-ETHNIC COHORT
Authors: S. S. Shaharir, M. S. Mohamed Said, S. Rajalingham, H. Mahadzir, R. Mustafar, A. Abdul Wahab
Journal: Annals of the Rheumatic Diseases (2020)

Background: Systemic Lupus Erythematosus (SLE) commonly affects young women in their reproductive age group. However, there is an increase prevalence of late-onset SLE, parallel to the higher life expectancies among general populations worldwide. It has been reported that up to 25% SLE populations have a later onset of disease and their disease expression and course may be different. Objectives: To determine the clinical features and outcomes of late-onset SLE patients in a multi-ethnic Malaysian cohort. Methods: Medical records of SLE patients who attended regular follow-up clinics in Universiti Kebangsaan Malaysia Medical Centre (UKMMC) from 2011 until June 2019 were reviewed. Late-onset SLE was defined as the onset of SLE symptoms or diagnosis after the age of 50 years old. Information on their socio-demographics and disease characteristics were obtained from the clinical records. Disease damage was assessed using the SLICC/ACR (Systemic Lupus International Collaborating Clinics/American College of Rheumatology) Damage Index (SDI) scores. The disease characteristics and autoantibody profiles were compared between late-onset and younger onset patients. Damage accrual at disease onset and at 5 years was obtained and compared between the two groups. Results: A total of 429 patients were included and majority of them were Malays (n= 225, 52.4%) followed by Chinese (n=180, 42), Indian (n=21, 4.9%) and others (n=3,0.7%). This multi-ethnic SLE cohort was consisted of predominantyly female patients (n=372,86.7%) with disease duration of 9.9 years ± 6.8 years. A total of 13.8% (n=59) had late onset SLE with mean onset of disease at 58.1 ± 6.3 years while younger group was 27.2 ± 9.4 years. The commonest system involvement among the late-onset group was haematological manifestation (69.5%).Compared to the younger-onset SLE, late-onset SLE occurred significantly higher among the Chinese (66.1%) as compared to Malay (32.3%), Indians and other ethnics (1.7%), p&lt;0.01. Patients with late-onset SLE also had significantly less musculoskeletal (37.3% vs 62.4%) and renal (23.7% vs 71.1%), p&lt;0.001 and tend to have less muco-cutanoues manifestations (28.8 vs 42.4%, p=0.06). Meanwhile, pulmonary involvement was more common among the late onset SLE patients (11.9% vs 0.8%, p&lt;0.001). Extractable nuclear antigen (ENA) results were available in 197 patients and patients with late-onset SLE had significantly higher rate of anti-RO positive (63% vs 3.9%), p=0.01. Otherwise, no significant difference in the other autoantibodies expressions including anti-La, anti-Sm, anti-RNP, anti-ribosomal P and anti-phospholipid antibodies. Patients with late-onset SLE tend to have more damage accrual at 5 years as compared to the younger age group (p=0.07). The mortality in the late onset group was 13.6% (n=8) as compared to 2.7% (n=10) in the younger age group, p=0.01. Majority of the cause of death in the later onset SLE was infection (87.5%) while in the younger age group was infection and active disease (90%). Conclusion: Late onset SLE occurs more commonly among Chinese ethnics in Malaysia and Malaysian SLE patients with late onset of the disease have distinct clinical manifestations. Damage accrual at 5 years tend to be higher in the late-onset group and the mortality is significantly higher with the major cause of death is infection. The different disease expression and outcome in late onset SLE suggest different factors in influencing the disease course and hence further studies including their genetic profiles are warranted. References: [1]Paula I. Burgos; Graciela S. Alarcón. Late-onset Lupus: Facts and Fiction. Future Rheumatol. 2008;3(4):351-356. [2]S Stefanidou, C Gerodimos, A Benos et al. Clinical expression and course in patients with late onset systemic lupus erythematosus. Hippokratia. 2013; 17(2): 153–156. Acknowledgments: This research was supported by the “Fundamental Research Grant Scheme (FRGS/1/2018/SKK02/UKM/03/1)” by Ministry of Education Malaysia Disclosure of Interests: Syahrul Sazliyana Shaharir: None declared, Mohd Shahrir Mohamed Said: None declared, Sakthiswary Rajalingham Speakers bureau: Pfizer (500USD), Hazlina Mahadzir: None declared, Ruslinda Mustafar: None declared, Asrul Abdul Wahab: None declared