Table 4: Longitudinal multivariate analysis of body lead burden 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) <0.001
Gender (female versus male) <0.001
Smoking (no versus yes) 0.813
Body-mass index (each increment of 1 kg/m2) 0.852
History of cardiovascular diseases (no versus yes) 0.686
MAP (mmHg) (each increment of 1 mmHg) 0.033
Cholesterol (mg/dL) (each increment of 1 mg/dL) 0.811
Triglycerides (mg/dL) (each increment of 1 mg/dL) 0.075
HbA1c (%) (each increment of 1%) 0.793
Serum creatinine (mg/dL) (each increment of 1 mg/dL) <0.001
Body lead burden (μg) (each increment of 1  g) 0.009
Daily protein intake (g/kg) (each increment of 1 g/kg) 0.460
Daily protein excretion (g) (each increment of 1 g) 0.035

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.