Disease patterns of rheumatology outpatients seen in a tertiary hospital serving a multi- ethnic, urban Asian population in Singapore

AimsTo describe the spectrum of diseases seen in an outpatient setting in the Singapore General Hospital, the largest tertiary referral centre in Singapore. MethodsIn this cross-sectional study, medical records of patients scheduled for an appointment at the rheumatology specialist outpatient clinics over a 4-month period (10 August 2010-31 December 2010) were reviewed. Primary diagnoses documented by the attending physician at the latest visit were recorded. ResultsAmong 4180 patients (29.5% male; mean [SD] age: 53.5 [15.1] years; 77.0% Chinese, 8.0% Malay, 8.8% Indian and 6.2% others), the spectrum of diseases seen was as follows [disease - definite n (%), probable n (%)]: Arthritis: rheumatoid arthritis - 958 (22.9%), 68 (1.6%); osteoarthritis - 452 (10.8%), 39 (0.9%); crystal arthritis - 417 (10.0%), 18 (0.4%); spondyloarthritis - 227 (5.4%), 61 (1.5%); psoriatic arthritis - 158 (3.8%), 9 (0.2%); other inflammatory arthritis - 153 (3.7%), 94 (2.2%); Connective tissues diseases: systemic lupus erythematosus - 412 (9.9%), 26 (0.6%); vasculitis - 105 (2.5%), 22 (0.5%); Sjogren's syndrome - 81 (1.9%), 32 (0.8%); overlap syndromes - 73 (1.8%); scleroderma - 50 (1.2%), 4 (0.1%); undifferentiated connective tissue diseases - 45 (1.1%), 106 (2.5%); myositis - 41 (1.0%), 12 (0.3%); antiphospholipid syndrome - 22 (0.5%), 7 (0.2%); polymyalgia rheumatica - 16 (0.4%); Others: soft tissue rheumatism - 155 (3.7%); osteoporosis - 61 (1.5%); other non-rheumatologic conditions - 189 (4.5%); other rheumatologic conditions - 67 (1.6%). ConclusionRheumatoid arthritis, osteoarthritis and crystal arthritis were the three most common rheumatological diseases seen in a tertiary referral centre serving a multi-ethnic urban Asian population in Singapore.