Age-dependent decline in renal function in patients with lung cancer

The aim of this study was to clarify the effect of aging on renal function. Serum creatinine (SCr), blood urea nitrogen (BUN) and 24-h creatinine clearance (measured-CrCl) were examined in lung cancer patients and the measured-CrCl were compared with CrCl estimates by employing two commonly used equations. In total, 787 lung cancer patients who were diagnosed between 2001 and 2010 were retrospectively analyzed. SCr and urine creatinine, BUN and measured-CrCl were evaluated prior to treatment. The Cockcroft-Gault (CG) and modification of diet in renal disease (MDRD) formulae were also used to estimate CrCl. SCr, BUN and measured-CrCl showed a significant decline in the elderly. In the 787 lung cancer patients, a significant correlation coefficient was found between measured-CrCl and age. However, in patients aged 80 years or older, no significant correlation coefficient was found between measured-CrCl and age. In the comparison between the measured CrCl and the CrCls estimated by the two formulae, the CG-CrCl levels were lower than those of the measured-CrCl, whereas the MDRD-CrCl levels were higher. Age is a crucial factor influencing renal function in patients with lung cancer. Particularly in the elderly, a decline in CrCl and greater individual variability in CrCl, as well as discrepancies in measured-CrCl and estimated CrCls are significant factors.