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Background: Sickle cell trait (SCT) is common among African Americans and has been historically considered to be benign. Recently, SCT has been associated with an increased risk for chronic kidney disease (CKD) and cardiovascular disease in the general population. Our understanding of SCT has been extrapolated largely from data of patients with sickle cell disease (SCD). Notably, in SCD, the outcomes differ by sex. The effect of SCT on cardiovascular risk in the African American CKD population is unknown, and the interaction between SCT and sex on cardiovascular risk has not been investigated.Methods: We performed a 2-center retrospective cohort study of all African American patients with SCT using international classification of disease diagnosis codes and CKD (using the 2012 Kidney Disease Improving Global Outcomes criteria) with at least 1 year of follow-up between January 2005 and December 2017. A reference group of -African American CKD patients without SCT was used as a comparator during the same period. SCT patients and the reference patients were matched at baseline for age, sex, comorbidities, and proteinuria. Primary outcomes were incident coronary artery disease (CAD), incident stroke, and all-cause mortality. Analysis of effect modification between sex and SCT on primary outcomes was performed.Results: We identified 621 African American CKD patients, 217 SCT patients, and 404 reference patients. The mean age was 56 ± 13 years and 66% were female. The mean estimated glomerular filtration rate was 69 ± 30 mL/min. The mean follow-up time was 8 ± 4 years. There were no significant differences in the primary outcomes comparing SCT patients to matched controls. The interaction term between SCT and sex, however, was significant in the CAD model (p < 0.01). Stratification by sex showed no increased risk in females but a significantly increased risk for CAD in male SCT patients (hazard ratio [HR] 2.14; 95% CI 1.18-3.86), which persisted after multivariable analysis (HR 2.13; 95% CI 1.17-3.86).Conclusion: SCT is associated with an increased risk for CAD in African American males with CKD. The excess risk in males with SCT appears to follow the same pattern as risk in males with SCD. Larger studies are needed to confirm these findings. [ABSTRACT FROM AUTHOR]

Background: Compared to the past, patients with sickle cell disease (SCD) currently live longer due to improvements in diagnosis and comprehensive care. Due to these advances, long-term chronic complications pose a greater challenge in the management of patients with SCD. In particular, sickle cell nephropathy (SCN) is associated with significant morbidity and mortality across all age groups. Furthermore, SCN is an understudied condition with relatively few symptoms and therefore requires close surveillance. In this review, we sought to explore the epidemiology, natural history, and treatment options for SCN with an emphasis on the pediatric population. Summary: SCN invariably begins in childhood with evidence of structural changes detected as early as infancy. These indolent changes can progress undetected to advanced chronic kidney disease by late adolescence or early adulthood. The risk factors for progression are not well defined, but significant albuminuria (which is also the most common presentation in childhood) is a key factor in progression. One of the main challenges in understanding SCN in children is the poor correlation between estimated and measured glomerular filtration rates. Another challenge is the lack of large-scale longitudinal studies that track the clinical outcomes of pediatric patients over time. Several studies aim to identify early biomarkers of SCN in children, as albuminuria presents only following significant chronic damage. The utility of angiotensin converting enzyme inhibitors and hydroxyurea in treating albuminuria is addressed here as well as novel treatments that may be of benefit. [ABSTRACT FROM AUTHOR]