Table 3.

Multiplicative interaction tests between baseline corrected serum calcium and baseline eGFR in its association with subsequent kidney function decline (95%-CI).

	All patients (n = 15,755)	P*
Additional change in eGFR decline per each mg/dL higher albumin-corrected calcium for each mL/min/1.73 m2 higher unit of eGFR (negative = smaller effect)
Raw data	−0.021 (−0.032; −0.009)	<0.001
Model 1	−0.019 (−0.030; −0.008)	0.001
Model 2	−0.019 (−0.030; −0.008)	0.001

Model 1 adjusted for age, sex, blood pressure, DM, CVD serum albumin and hemoglobin. Model 2 adjusted for covariates in model 1 plus serum phosphorus, active vitamin D therapy and calcium supplements. *P-value for difference in the change in the rate of kidney function decline with one unit higher serum calcium.