Patients With Late-Onset SLE Have Clinical Differences From Those With Early-Onset SLE

Early- vs late-onset systemic lupus erythematosus (SLE) is linked to higher rates of organ damage, except for kidney involvement, according to research results published in Advances in Rheumatology.

Researchers aimed to compare clinical and serologic features in patients with early- vs late-onset SLE.

A sex- and year at diagnosis-matched case control study was conducted using medical records of patients with SLE between January 1994 and June 2020. Patients aged 18 years and older at diagnosis with a follow-up of at least 1 year were included in the study.

Demographic information, clinical manifestations, serology and laboratory findings, disease duration and treatment and outcomes were all recorded. Disease activity was determined by the SLE Disease Activity Index 2000 (SLEDAI-2K), and organ damage was recorded using the Systemic Lupus International Collaborating Clinics/American College of Rheumatology (SLICC/ACR) damage index (SDI).

Patients were divided into the early- and late-onset groups if SLE was diagnosed at age younger than 50 years and older than 50 years, respectively. Patients with early-onset SLE were matched 2:1 with those with late-onset SLE, according to sex and year of diagnosis (±1 year).

A total of 62 patients with early- and 124 late-onset SLE were included in the study, with a mean follow-up of 5 years. Mean age of diagnosis for early- and late onset SLE was 30.9 years and 56.3 years, respectively.

Compared with early-onset SLE, those with late-onset SLE were found to have a higher frequency of serositis (P <.001) and hemolytic anemia (P =.034), and a lower frequency of malar rashes (P =.001), arthritis (P =.009), leukopenia (P =.022) and lymphopenia (P =.034).

In addition, patients with late- vs early-onset SLE were found to have a higher frequency of cardiomyopathy (P =.046), lupus endocarditis (P =.049) and interstitial lung disease (P =.020) at diagnosis, but a lower frequency of cutaneous vasculitis (P =.026).

Patients with late- vs early-onset SLE received a lower rate of antimalarials (53.2% vs 67.7%; P =.053), but a higher rate of immunosuppressive medications (35.5% vs 25.8%; P =.170).

Patients with late- vs early-onset SLE had higher SDI scores (P <.001); however, after adjusting for baseline clinical and laboratory values at the time of diagnosis, kidney involvement, antidouble stranded DNA antibody (anti-dsDNA), and mean number of ACR classification criteria were lower in patients with late- vs early-onset SLE (P =.002, P =.049, and P =.008, respectively).

The incidence rate per 100-person years of death was higher in patients with late vs-onset SLE (3.2 vs 1.1; P =.015), irrespective of comorbidities at time of diagnosis (9.1 vs 3.2; P =.037).

Study limitations included the exclusion of a large number of patients with early-onset SLE, which may not have represented the entire population.

Overall, the study authors concluded, “[T]he late-onset SLE patients had less renal involvement and received less aggressive treatment, but had a higher mortality rate than the early-onset patients.”