Isoquercetin for thromboinflammation in sickle cell disease: a randomized double-blind placebo-controlled trial.

ABSTRACT: Data from a small trial in patients with cancer suggest that isoquercetin (IQ) treatment lowered thrombosis biomarkers and prevented clinical thrombosis, but, to our knowledge, no studies of IQ have been conducted to target thromboinflammation in adults with sickle cell disease (SCD). We conducted a randomized, double-blind, placebo-controlled trial in adults with steady-state SCD (hemoglobin SS [HbSS], HbSß0thal, HbSß+thal, or HbSC). The primary outcome was the change in plasma soluble P-selectin (sP-selectin) after treatment compared with baseline, analyzed in the intention-to-treat population. Between November 2019 and July 2022, 46 patients (aged 40 ± 11 years, 56% female, 75% under hydroxyurea treatment) were randomized to receive IQ (n = 23) or placebo (n = 23). IQ was well tolerated and all the adverse events (AEs; n = 21) or serious AEs (n = 14) recorded were not attributable to the study drug. The mean posttreatment change for sP-selectin showed no significant difference between the treatment groups (IQ, 0.10 ± 6.53 vs placebo, 0.74 ± 4.54; P = .64). In patients treated with IQ, whole-blood coagulation (P = .03) and collagen-induced platelet aggregation (P = .03) were significantly reduced from the baseline. Inducible mononuclear cell tissue factor gene expression and plasma protein disulfide isomerase reductase activity were also significantly inhibited (P = .003 and P = .02, respectively). Short-term fixed-dose IQ in patients with SCD was safe with no off-target bleeding and was associated with changes from the baseline in the appropriate direction for several biomarkers of thromboinflammation. The trial was registered at www.clinicaltrials.gov as #NCT04514510.

Cognitive deficits are associated with unemployment in adults with sickle cell anemia.

An estimated 25-60% of adults with sickle cell disease (SCD) are unemployed. Factors contributing to the high unemployment rate in this population are not well studied. With the known risk of cognitive deficits associated with SCD, we tested the hypothesis that unemployment is related to decrements in intellectual functioning. We conducted a retrospective chart review of 50 adults with sickle cell anemia who completed cognitive testing, including the Wechsler Adult Intelligence Scale-IV, as part of standard care. Employment status was recorded at the time of testing. Medical variables examined as possible risk factors for unemployment included disease phenotype, cerebral infarction, and pain frequency. The mean age of the sample was 30.7 years (range = 19-59); 56% were women. Almost half of the cohort (44%) were unemployed. In a multivariate logistic regression model, lower IQ scores (odds ratio = 0.88; p = .002, 95% confidence interval, CI [0.82, 0.96]) and lower educational attainment (odds ratio = 0.13; p = .012, 95% CI [0.03, 0.65]) were associated with increasing odds of unemployment. The results suggest that cognitive impairment in adults with sickle cell anemia may contribute to the risk of unemployment. Helping these individuals access vocational rehabilitation services may be an important component of multidisciplinary care.