Association of Red Cell Distribution Width with Pediatric Obstructive Sleep Apnea and Post-Tonsillectomy Bleeding

Introduction: Obstructive sleep apnea (OSA) is common in pediatric patients, and while polysomnography is the gold standard for diagnosis, it is costly and time-consuming, making biomarkers a useful alternative. Red cell distribution width (RDW), which measures variation in red blood cell size, has been suggested as a potential biomarker. This study evaluates RDW as a potential biomarker for pediatric OSA diagnosis and explores its association with post-tonsillectomy bleeding.

Methods: A retrospective study from 2006 to 2024 in the TriNetX database identified patients ≤17 years with RDW values either ≤14.5% (low RDW, LRDW) or >14.5% (high RDW, HRDW). Cohorts were propensity score matched by age, sex, race, and ethnicity. Outcomes of OSA were analyzed using ICD-10 code G47.33. OSA patients who underwent tonsillectomy were further analyzed. Tonsillectomy procedures were identified with CPT codes 42820, 42821, 42825, and 42826, SNOMED codes 173422009 and 28913000, and ICD-10-PCS code 0CTP. Matched OSA patients with LRDW and HRDW who underwent tonsillectomy were analyzed for two-week post-tonsillectomy bleeding outcomes.

Results: After matching, 523,301 patients were included in the LRDW and HRDW cohorts. HRDW patients had similar odds of having OSA as LRDW patients (N=12,230, 2.3% vs. N=12,342, 2.4%; OR=0.99, 95% CI=0.97-1.02, p=.47). 578 HRDW patients were matched with 578 LRDW patients who had OSA and underwent tonsillectomy. Mean age at OSA diagnosis was 6.5 years (SD=4.4). The mean RDW was 12.9% (SD=0.7) in the LRDW cohort and 18% (SD=4.5) in the HRDW cohort. The LRDW group were more likely to bleed post-tonsillectomy (N=45, 6.9%) compared to the HRDW group (N=27, 4.1%; OR=1.72, 95% CI=1.05-2.77, p=.029). No significant differences in coagulation panel results were observed between the HRDW and LRDW cohorts.

Conclusions: While RDW does not appear to predict OSA, lower RDW is associated with a higher risk of post-tonsillectomy bleeding in children with OSA, independent of coagulation parameters. RDW may help predict bleeding risk in pediatric OSA patients, though further research is needed to confirm its clinical utility.