Height-corrected low bone density associates with severe outcomes in sickle cell disease: SCCRIP cohort study results

Area of Science:

• Pediatric Hematology
• Bone Metabolism Research
• Sickle Cell Disease Complications

Background:

• Low bone mineral density (BMD) is a prevalent issue in individuals with sickle cell disease (SCD).
• Previous studies often overlook the impact of short stature on BMD measurements in pediatric SCD cohorts.
• Accurate BMD assessment in children with SCD requires adjustments for growth variations.

Purpose of the Study:

• To determine the prevalence of low BMD in pediatric patients with SCD, specifically adjusting for height.
• To identify demographic and clinical factors associated with low height-adjusted BMD (Ht-aBMD) in this population.
• To establish a baseline for future longitudinal studies on BMD and SCD progression.

Main Methods:

• Analysis of 306 children and adolescents (6-18 years) from the Sickle Cell Clinical Research and Intervention Program (SCCRIP) cohort.
• Calculation of areal BMD and height-adjusted areal BMD (Ht-aBMD) z-scores using reference data from healthy African American children.
• Logistic regression used to assess associations between low Ht-aBMD (z-scores ≤ -2) and clinical/demographic characteristics.

Main Results:

• 18% of the pediatric SCD cohort exhibited low Ht-aBMD z-scores, indicating low BMD even after height adjustment.
• Low Ht-aBMD was significantly associated with adolescence (OR, 7.7), hip osteonecrosis (OR, 4.0), and chronic pain (OR, 10.4).
• Lower hemoglobin levels were also associated with lower Ht-aBMD z-scores (OR, 0.74).

Conclusions:

• A significant proportion of pediatric SCD patients experience low BMD, underscoring the need for height-adjusted assessments.
• Adolescence, hip osteonecrosis, and chronic pain are key clinical factors linked to reduced BMD in pediatric SCD.
• Prospective evaluation of Ht-aBMD in the maturing SCCRIP cohort will further elucidate its relationship with SCD morbidity.