 A patient with a greater muscle mass will have a higher creatinine concentration.While a baseline serum creatinine of 2.0 mg/dL (177 μmol/L) may indicate normal kidney function in a male body builder, a serum creatinine of 1.6 mg/dL (110 μmol/L) can indicate significant renal disease in an elderly female.The trend of serum creatinine concentrations over time is more important than absolute creatinine concentration.