Article Text
Abstract
Background Systemic lupus erythematosus (SLE) is a disease characterised by auto-antibody production. A wide variety of antibodies to extractable nuclear antigens (ENA) and double-stranded DNA (dsDNA) are frequently observed. This study aimed to assess the clinical significance of these antibodies within a large lupus cohort across 40 years of follow-up, with particular importance placed upon progression and time to damage.
Methods A retrospective review of patient medical records from the University College London Hospital (UCLH) lupus clinic since inception in 1978 was performed. All patients were required to fulfil revised ACR criteria for a diagnosis of SLE. ENA (including anti-Ro, anti-La, anti-RNP, anti-Sm) and anti-dsDNA were recorded as positive if they had ever been found to be present. A variety of clinical manifestations were recorded. Furthermore, the time from diagnosis to the first onset of SLICC criteria damage was measured. Statistical analysis was performed using chi squared and Student’s t test with a p-value<0.05 felt to be statistically significant.
Results A total of 170 patients were identified (mean age at diagnosis was 30 years old; 93% female; mean follow-up time was 22 years). 139 (82%) had sustained damage, and 54 (32%) had died. 59% (100/170) were anti-dsDNA positive, 13% (22/170) were anti-Sm positive, 28% (47/170) were anti-RNP positive, 38% (64/170) were anti-Ro positive, and 12% (20/170) were anti-La positive. There was a significant association between anti-dsDNA positivity and developing damage (see table 1). There was no difference in mean time to damage for all antibodies analysed. These antibodies did not show significant association with death. Anti-dsDNA positivity associated with renal damage (p<0.0001), and there was a statistically significant association between anti-Sm positivity and alopecia (p=0.049).
Conclusion Within this large lupus cohort followed up over 40 years, a significant association between anti-dsDNA and damage is observed. No association was found between antibody positivity and death, or time to damage.