Table 5: Longitudinal multivariate analysis of blood lead level and other predictors of progressive change in the estimated glomerular filtration rate (D-GFR), using generalized estimating equations, during the 24-month longitudinal study period ( ).

VariableEstimate (interactive effect)* value

Age (each increment of 1 yr)−0.268<0.001
Gender (female versus male)−3.261<0.001
Smoking (no versus yes)−0.6310.604
Body-mass index (each increment of 1 kg/m2)−0.0180.861
Previous cardiovascular diseases (no versus yes)−0.2200.818
MAP (mmHg) (each increment of 1 mmHg) 0.025
Cholesterol (mg/dL) (each increment of 1 mg/dL)−0.0060.406
Triglycerides (mg/dL) (each increment of 1 mg/dL) 0.024
HbA1c (%) (each increment of 1%)−0.0020.976
Serum creatinine (mg/dL) (each increment of 1 mg/dL)−7.550<0.001
Blood lead level (μg/dL) (each increment of 1 μg/dL)−0.2980.010
Daily protein intake (g/kg) (each increment of 1 g/kg) 1.143 0.539
Daily protein excretion (g) (each increment of 1 g)−0.4000.045

The interactive effect of variables was calculated by a generalized estimating equation. Negative values for the interactive effect indicate a decline in the glomerular filtration rate, and positive values indicate an increase. Cardiovascular diseases included ischemic heart disease, congestive heart failure, stroke, and diabetic foot. MAP: mean arterial pressure.