Cognitive impairment is a common and dreaded complication of sickle cell disease (SCD), profoundly affecting patients' quality of life, education, and employment. Despite its significance, there is a striking lack of guidance on optimal screening strategies, with existing tools often skewed by biases related to language proficiency and educational background, leaving many patients undiagnosed and unsupported. The Rowland Universal Dementia Assessment Scale (RUDAS) was specifically designed for cognitive screening in multicultural populations. We hypothesized that in adults with SCD, RUDAS performance is less influenced by educational attainment when compared to the Montreal Cognitive Assessment (MoCA). We conducted a cross-sectional study of adults with SCD who underwent cognitive screening at the Henri-Mondor Hospital using RUDAS and MoCA. Educational attainment was scored as the years of schooling for the highest completed diploma (HLE). Abnormal RUDAS (<28) and MoCA (<26) scores were found in 55/73 (75.3%) and 52/73 (71.2%). Both scores increased significantly with HLE (p < 0.001). Adding 1 point for those with the HLE < 12 years significantly mitigated the effect of education on RUDAS but only partially for MoCA (p = 0.26 and p = 0.003). In an independent cohort of 252 adults, this adjustment for HLE significantly lessened the effect of education on RUDAS. These results suggest there is an educational bias in neurocognitive screening of adults with SCD. We propose that the RUDAS adjusted for HLE is a promising novel strategy to systematically identify those in need of comprehensive neurocognitive assessment.
Keywords: MoCA; RUDAS; Sickle cell disease; cognitive impairment; cognitive screening.