Cognitive impairment is a complication of sickle cell disease (SCD) that can severely impact patients’ lives. However, research in this area is lacking. This study, published in Blood, compared the cognitive function of patients with SCD to that of a healthy control group.
Patients with mild to severe SCD were recruited from the University of Pittsburgh Medical Center Adult Sickle Cell Program. Sex- and age-matched controls were referred by program participants and recruited from the community. Of note, unlike past studies, this study included patients with all types of SCD comorbidities.
Of the 86 patients with SCD and the 66 controls, most were female and had a mean age of 36 years old. On average, the patients with SCD had severe disease, were less educated, and were more likely to smoke. Moreover, 14% had a history of stroke, and 20% were receiving chronic exchange transfusions.
Ultimately, it was found that patients with SCD had significantly lower scores in 5 of 10 cognitive domains, including attention and processing, language, and executive function. The deficits in attention and processing held even after adjusting for hemoglobin level, pre-morbid verbal IQ, and smoking history.
Moreover, the severity of the cognitive deficits did not seem to depend directly on disease severity, as no significant differences in cognitive domain scores were found between patients with mild SCD and those with severe disease. However, patients with SCD and a history of stroke did have significantly worse executive function scores than those without a history of stroke.
As a whole, these findings underscore the disparities in cognitive function between patients with SCD and those without SCD. Given that the severity of cognitive deficits in patients with SCD does not seem to directly depend on disease severity, more research is needed to better understand the pathogenesis of cognitive impairment in this population .
Source: Portela, G., Butters, M., Brooks, M. M., Candra, L., Rosano, C., & Novelli, E. M. (2021). Comprehensive assessment of cognitive function in patients with sickle cell disease reveals deficits in memory and processing speed. Blood, 138(Supplement 1), 975. https://doi.org/10.1182/blood-2021-151576