Analysis of trends and causes of death in SLE patients over a 40-years period in a cohort of patients in the United Kingdom

Abstract

Background

Systemic Lupus Erythematosus (SLE) an autoimmune rheumatic disease with a complex pathogenesis, remains potentially life-threatening. SLE patients have increased morbidity and premature mortality compared to non-SLE patients. The five-year survival rate has improved from <50% in the 1950s to >90% in the 1980s. Lupus patients still have a mortality risk three times that of the general population.

Objectives

To provide a detailed analysis of the causes of death, main characteristics and trends in the management of the deceased SLE patients from the lupus clinic at the University College London Hospital (UCLH); during the past four decades.

Methods

This was a non-interventional, retrospective study based on historical real-world data from paper and electronic records of patients followed up at UCLH. The analysis focused on data collected between 1st January 1978 and 31th December 2018. We collected the: causes of death, duration of disease, key laboratory and clinical parameters and the treatment received. We compared the results from the four decades to ascertain trends in the causes of mortality. All statistical analyses were performed using the Statistical Package for Social Sciences (SPSS), version 22.0. The 95% confidence intervals for the means of data were calculated.

Results

111 SLE patients (15%), died during follow-up. Their median age was 51 years (interquartile range (IQR) = 38–63 years) and the median duration of disease, 15 years (IQR = 8.5–24 years). The main causes of death in the past 40 years were infection (31.7%), cancer (26.7%) and cardiovascular disease (CVD) (21.8%). 93.6% of these patients were immunosupressed. During the 40-year period, there were several therapeutic developments notably the introduction of mycophenolate mofetil (MMF) and rituximab; the latter initially only given to patients when more conventional inmunosupressants had failed, but more recently offered to patients at diagnosis. There was a statistically significant increase in the use of hydroxycloroquine (HCQ), MMF and rituximab. In contrast, the use of Azathioprine (AZA) and steroids, hardly changed over time.

Conclusions

This retrospective review shows how epidemiological factors, causes of death and treatment of SLE patients have changed during the last 40 years in the UCLH cohort.