Elderly Onset Rheumatoid Arthritis in Black South Africans

Abstract

Introduction: Rheumatoid arthritis (RA) differs between young and elderly onset disease. We aimed to study differences in joint involvement, disease activity, functional status, serology and extra-articular manifestations between young onset RA (YORA) (≤59 years) and elderly onset (EORA) (≥60 years) in South Africans. Methods: A retrospective records review of RA patients fulfilling the 2010 American College of Rheumatology RA classification criteria at a tertiary hospital in Gauteng, South Africa. Consecutive case records for the period 2015 to 2023 were reviewed. Results: The overall cohort of 482 patients, 358 with YORA and 124 with EORA, had a median age (IQR) at onset of 50 (37-60) years, were predominantly female (84.4%) with median symptom duration of 18 months. Median age (IQR) at onset was 44 (35-52) years in YORA compared to 65 (62-70) years in EORA. With no significant differences in sex distribution (83.2% vs. 87.9% females, NS), symptom duration (18 (6-36) months vs. 23 (7.75-48) months, NS), or with respect to joint pain and swelling between the groups. There was a trend towards more early morning stiffness (EMS) in the YORA group (84.4% vs 76.6%, p=0.05). Patients with EORA had significantly more metacarpophalangeal (MCP) joint involvement (86.3% vs 77.9%, p=0.04), and more disability as assessed by the American College of Rheumatology functional classification, compared to patients with YORA. There were no differences in disease activity, serology or extra-articular manifestations between the groups. Conclusion: In Black South Africans with RA, YORA presents with a trend towards more EMS, while EORA with significantly more MCP joint involvement and functional disability