According to a study results, systemic lupus erythematosus (SLE) patients have impaired memory and learning abilities.
The memory domain has been shown to be impaired frequently in patients with SLE, Dr. D. Paran, of Tel-Aviv Medical Center, Israel, and colleagues note. Several studies have attempted to characterize the pattern or profile of cognitive impairment in SLE, aiming to understand better the pathogenesis of these deficits.
The study evaluated total of 40 consecutive, unselected patients who were compared to 40 healthy matched controls. Median disease duration was 8 years in the SLE patients (median age 33 years).
Overall, 10 patients had antiphospholipid antibodies without antiphospholipid syndrome, 12 patients had the antiphospholipid syndrome, and 18 patients were antiphospholipid antibody negative. The Beck Depression Inventory detected depression in 16 out of the 40 patients.
The authors reported that SLE patients were found to have impairments in several aspects of the memory domain, as measured by the Rey Auditory Verbal Learning Test. The learning curve was significantly less steep in SLE patients (p = 0.036) when compared with controls.
Compared to control group, in the SLE group, the rate of words omitted from trial to trial was higher (p = 0.034) and retrieval was less efficient (p = 0.004). These findings remained significant after omitting patients with stroke or depression.
There was no correlation of memory impairment with SLE disease duration, disease activity, damage, steroid treatment, or the use of medication. Also memory measures did not correlate with the presence of depression.
Cognitive impairment has been associated with various autoantibodies including antineuronal and lymphocytotoxic antibodies, anti-ribosomal P antibodies, the persistent presence of antiphospholipid antibodies and possible anti-NR2 antibodies, as well as increased levels of serum matrix metalloproteinase 9 (MMP-9), suggesting an association with small vessel cerebral ischemic events, Dr. Paran and colleagues report.
In our cohort, 22 patients had antiphospholipid antibodies on repeated tests, 12 of whom had the antiphospholipid syndrome, suggesting that the high prevalence of these antibodies may account, at least in part, for the high prevalence of memory impairment.