Objective To estimate the risk of mortality in the Finnish incident SLE cohort in a 16-year period compared with the general population. Methods Adults with new-onset SLE between 1 January 2000 and 31 December 2014 identified from the national drug reimbursement register and their individually matched controls from the Population Register Centre were followed up until death or 31 December 2015. Data on deaths were retrieved from the national causes of death register. Comorbidities and education were obtained by linkage to the other national registries. Results A total of 1006 patients with incident SLE and 3005 population controls were found (mean follow-up 8.6 years). Of these, 98 SLE patients subsequently died. Their 5 -, 10-, and 15-year survival rates were 95.0% (95% CI: 93.3, 96.2), 88.8% (86.2, 91.0), and 82.1% (77.6, 85.8), respectively. Crude hazard ratio (HR) was 1.61 (95% CI: 1.26, 2.06), adjusted for education level was almost the same 1.61 (95% CI: 1.26, 2.05). After adjustment for comorbidities and education at baseline, the difference in mortality disappeared: HR 1.14 (95% CI: 0.88, 1.48). The leading causes of death were cardiovascular diseases (CVDs) (33%), malignancies (27%) and neurological diseases (10%). Subhazard ratio for CVD deaths was 1.28 (95% CI: 0.85, 1.93), adjusted for comorbidities and education 0.88 (95% CI: 0.56, 1.39). Conclusions These results suggest that the increased mortality in SLE patients is highly associated with comorbidities present at diagnosis. This underlines the importance to screen and treat comorbidities and disease actively without delays.

The objective of the study was to examine the risk of other morbidities among patients with systemic lupus erythematosus (SLE). A total of 1006 adult new-onset SLE patients were identified during 1.1.2000- 31.12.2014 from the register of Social Insurance Institution. For each case three general population controls matched according to age, sex and place of residence at the index day were sampled from the population register. Both groups were followed up from the index date until the end of 2017 or until death. The national register on specialized care was explored to gather broadly their 12 organ-specific morbidities, which were found among 91.2% of SLE patients and 66.7% of comparators. The rate ratio (RR) was elevated in almost all disease groups. Musculoskeletal, cardiovascular and genitourinary conditions were the most common comorbidities with RRs of 1.82 (1.68 to 1.97), 1.91 (1.76 to 2.08) and 1.91 (1.73 to 2.09), respectively. Men with SLE had a significantly higher risk for diseases of the genitourinary system and endocrine, nutritional and metabolic diseases compared to women with SLE. The risk of concurrent morbidities is essential to note in the care of SLE patients.