Table 3.

Association between Black Race as Reported by the Participants or Percentage of African Ancestry and Measured GFR after Controlling for Non-GFR Determinants of Serum Creatinine.^*

Model	No. of Participants	Coefficient for Black Race vs. Non-Black Race (95% CI)	Coefficient for Percentage of African Ancestry, per 10% Increase (95% CI)
		% higher iGFR
Base model
ln (iGFR) = [race or African ancestry] + ln (serum creatinine) + age + sex	1248	12.8 (9.7 to 15.9)†	1.6 (1.2 to 1.9)†
Base model with potential explanatory variables considered individually
ln (iGFR) = [race or African ancestry] + ln (serum creatinine) + age + sex + any of the following:
Body-mass index	1248	13.8 (10.7 to 17.0)	1.7 (1.3 to 2.0)
Body-surface area	1248	13.1 (9.9 to 16.3)	1.6 (1.2 to 2.0)
Height	1248	12.0 (9.0 to 15.1)	1.5 (1.1 to 1.8)
Weight	1248	13.4 (10.3 to 16.6)	1.6 (1.3 to 2.0)
ln (bioelectrical impedance analysis phase angle)	1231	10.5 (7.5 to 13.6)	1.3 (0.9 to 1.6)
Bioelectrical impedance analysis–quantified fat-free mass	1226	12.4 (9.2 to 15.6)	1.5 (1.2 to 1.9)
24-Hr urinary excretion of creatinine	1248	10.7 (7.7 to 13.7)	1.3 (1.0 to 1.7)
Base model with several potential explanatory variables considered simultaneously
ln (iGFR) = [race or African ancestry] + ln (serum creatinine) + age + sex + height + fat-free mass + ln (bioelectrical impedance analysis phase angle) + 24-hr urinary excretion of creatinine	1226	8.7 (5.8 to 11.7)	1.1 (0.8 to 1.5)

^*The association between Black race or African ancestry and measured GFR persists even after consideration of non-GFR determinants of serum creatinine as potential explanatory variables.

^†The percent difference was obtained by exponentiating the coefficient for Black race or percentage of African ancestry in models with serum creatinine level, age, and sex in the full study sample (1248 participants).