Cancer-Specific Mortality in Chronic Kidney Disease: Longitudinal Follow-Up of a Large Cohort

Background and objectives Chronic kidney disease (CKD) is known to be associated with increased all-cause and cardiovascular mortality, but no large studies examined the cancer-specific mortality in non dialysis-dependent CKD patients. Such outcome data are needed for proper allocation of resources and would help to develop better preventive services. Design, setting, participants, & measurements Between 1998 and 1999, 123,717 adults were recruited from four health screening centers in Taiwan. The estimated glomerular filtration rate was calculated using the four-variable Modification of Diet in Renal Disease Study equation for the Chinese. Mortality was ascertained by computer linkage to the national death registry after a median follow-up of 7.06 years. Cox proportional hazards regression models were used to estimate the impact of CKD on cancer-specific mortality. Results A higher risk for overall cancer mortality was found in CKD patients compared with non-CKD patients (adjusted hazard ratio, 1.2). CKD was associated with increased mortality from liver cancer, kidney cancer, and urinary tract cancer, with an adjusted hazard ratio of 1.74, 3.3, and 7.3, respectively. A graded relationship between the severity of renal impairment and cancer mortality was also found. Conclusions Patients with CKD had a higher mortality risk of liver cancer, kidney cancer, and urinary tract cancer. This is the first large study that showed an inverse association between renal function and liver cancer mortality. The increased mortality could be caused by higher cancer incidence or worse response to cancer treatment. Future research is warranted to clarify the mechanism. Clin J Am Soc Nephrol 6: 1121-1128, 2011. doi: 10.2215/CJN.09011010