Multidimensional factors affecting mortality and causes of death in patients with systemic lupus erythematosus: a Finnish cohort study with more than 20 years of follow-up.

OBJECTIVE

To study multidimensional factors affecting long-term mortality and causes of death in patients with systemic lupus erythematosus (SLE).

METHOD: A cohort of 224 SLE patients from the Helsinki University Hospital was established in the early 2000s. Personal interviews, examinations, and chart reviews followed a protocol that included demographics, clinical data, education, socioeconomic factors, lifestyle, and laboratory tests. Causes of death were obtained from the official death certificate statistics of Statistics Finland.

RESULTS

The mean age of the patients was 47.4 years, and the median follow-up duration was 20.5 years. Eighty-two patients (36.6%) had died. Survival rates at 5, 10, and 20 years were 94.8%, 85.3%, and 63.1%, respectively. The overall standardized mortality ratio was 2.73 (95% confidence interval 2.20-3.39). In univariate analyses, baseline factors associated with mortality included age, disease duration, body mass index (BMI), education, income, damage score, comorbidities, renal failure, and smoking history. In multivariable analyses, independent predictors of mortality were age, damage score, and renal failure, and a trend was observed for BMI and smoking history. Common primary causes of death included cardiovascular diseases (CVDs) (29 patients, 35%), malignancies (22, 27%), and SLE (10, 12%). Infections were the immediate cause of death in 16 cases (20%).

CONCLUSION

Multidimensional factors are associated with increased long-term mortality in SLE, and independent predictors include age, damage score, and renal failure. To improve the outcome of SLE, our results emphasize active treatment of CVDs and their risk factors, major organ manifestations of the disease and infections, and targeted cancer screening.