Delayed diagnosis adversely affects outcome in systemic lupus erythematosus: Cross sectional analysis of the LuLa cohort.

Objective: Despite increased physician's awareness and improved diagnostic and serological testing in the recent years, the interval between the initial symptoms and the diagnosis of Systemic lupus erythematosus (SLE) is still very long. Our aim was to study this delay and its association to the outcome of the disease.

Methods: Information on demographics, onset of first symptoms, first physicians visit and time of diagnosis was assessed by self-reported questionnaires among SLE patients in Germany (LuLa cohort, n = 585) in the year 2012. Disease activity (Systemic Lupus Activity Questionnaire; SLAQ), disease related damage (Brief Index of Lupus Damage; BILD), health related quality of life (Short Form 12) and fatigue (FSS) were chosen as proxies for outcome. Linear regression analysis was used to analyze the association of the delay in diagnosis to the outcome, adjusted for age, disease duration and sex.

Results: Mean duration between the onset of symptoms and the diagnosis of SLE was 47 months (SD 73). The longer the time to diagnosis, the higher the disease activity (β = 0.199, p < 0.0001), the disease-related damage (β = 0.137, p = 0.002) and fatigue (β 0.145, p = 0.003) and the lower the health-related quality of life (physical β = -0.136, p = 0.004, mental β = -0.143, p = 0.004).

Conclusion: In systemic lupus erythematosus, longer time to diagnosis was associated with worse outcome. Concepts in care with the intention to shorten the time to diagnosis are needed to improve the long-term outcome of the disease.