Background The Epidemiology of Rheumatoid Arthritis (RA) is changing over time provided by several studies showing an increase in frequency and change in joint presentation.(1) Moreover, the characteristics of the disease may differ among different ethnicities and populations that necessitate studying each population to define its own pattern of RA.
Objectives Our aim was to define disease characteristics in a cohort of Egyptian RA patients by retrospective analysis of their medical records through a period of 20 years.
Methods Medical records of all cases who fulfilled the ACR 1987 criteria for diagnosis of RA starting from January 1995 till July 2015 were reviewed (n=3219). All patients were receiving medical follow–up at the Rheumatology outpatient clinic, Kasr AlAiny Hospital. Demographic data and disease characteristics were documented and statistically analyzed.
Results A total of 3219 patients fulfilling the ACR 1987 criteria of RA were identified in the duration (1995–2015), 84% were females with mean age 48.8±13.8 that was not significantly lower than that of males 49.1±15.7 (p-value=0.62).The mean age of onset was 36.1±13.4 years and the mean disease duration was 12.9±7.9 years.
Rheumatoid factor (RF) was detected in 49.9% of cases; erosions were found at diagnosis in 19.6% of patients.77.1% of RA cases presented with polyarticular and 22.9% with oligoarticular patterns.
There was a significant increase by 0.12% in newly diagnosed cases annually (P-value=0.01) throughout the period studied (20y) (Fig. 1), however there was a significant decrement by 0.4% annually in females (p-value=0.02). On the other hand there was a significant steady increase in the mean age of onset by 0.2 year annually (P-value<0.001). While, there was a steady decline in erosions by 0.5% annually (p-value=0.01)
Females were more prone to have erosions although this was not found to be statistically significant; on the other hand RF was significantly higher in the erosive group (32.6%). Similarly the mean age at disease onset and age at diagnosis were statistically significantly higher in the erosive group (p-value=0.002 and p-value<0.001 respectively).
Regarding Extra-articular manifestations at the time of diagnosis, there was a significant decline in the presence of subcutaneous nodules and Sicca symptoms by0.4% & 0.5% annually respectively (P-value=0.03).
Conclusions The present study describes the demographic and disease characteristics of RA in the largest retrospective study as regards Egyptian RA patients.
Gibofsky, A. (2012). Overview of epidemiology, pathophysiology, and diagnosis of rheumatoid arthritis. The American journal of managed care, 18(13 Suppl), S295–302.
Disclosure of Interest None declared