Table 5.

Independent associations of tricuspid regurgitation velocity in multiple linear regression analysis models adjusted for age, sex, site, and chronic transfusion program.

	Beta (95% CI)	Standardized beta	P
Analysis based on all participants with erythropoietin available*
Erythropoietin, IU/L, natural log	0.06 (0.02-0.11)	0.19	.003
Hemolytic component	0.05 (0.03-0.07)	0.27	< .001
Analysis based on participants with value for hemoglobin F available†
Hemoglobin F (%)	0.006 (0.001-0.01)	0.19	.023
Hemolytic component	0.06 (0.03-0.08)	0.35	< .001

^*n = 294; R-square = 0.19; variables entered into the analysis initially include erythropoietin, hemoglobin oxygen saturation, hemolytic component, and hydroxyurea therapy.

^†n = 142; R-square = 0.21; variables entered into the analysis initially include hemoglobin F percentage, hemoglobin oxygen saturation, hemolytic component, and hydroxyurea therapy. With hemoglobin F category in the model, P value for hemoglobin F = .002.