Mortality and Resource Use Among Individuals With Chronic Kidney Disease or Cancer in Alberta, Canada, 2004-2015

IMPORTANCE Although the public is aware that cancer is associated with excess mortality and adverse outcomes, the clinical consequences of chronic kidney disease (CKD) are not well understood. OBJECTIVE To compare the clinical consequences of incident severe CKD and the first diagnosis with a malignant tumor, focusing on the 10 leading causes of cancer in men and women residing in Canada. DESIGN, SETTING, AND PARTICIPANTS This population-based cohort study enrolled individuals aged 19 years and older with severe CKD or certain types of cancer between 2004 and 2015 in Alberta, Canada. Data were analyzed in November 2021. EXPOSURES Individuals were categorized as having severe CKD (based on estimated glomerular filtration rate <30 mL/min/1.73 m(2) or nephrotic albuminuria without dialysis or kidney transplantation) or nonmetastatic or metastatic cancer (defined by a diagnosis of lung, breast, colorectal, prostate, bladder, thyroid, kidney or renal pelvis, uterus, pancreas, or oral cancer). MAIN OUTCOMES AND MEASURES All-cause mortality, number of hospitalizations, total number of hospital days, and placement into long-term care were calculated after diagnosis. RESULTS Of 200 494 individuals in the cohort (104 559 women [52.2%]; median [IQR] age, 66.8 [55.9-77.7] years), 51 159 (25.5%) had incident severe CKD, 115 504 (57.6%) had nonmetastatic cancer, and 33 831 (16.9%) had metastatic cancer. Kaplan-Meier 1-year survival was 83.3%(95% CI, 83.0%-83.6%) for patients with CKD, 91.2%(95% CI, 91.0%-91.4%) for patients with nonmetastatic cancer, and 52.8%(95% CI, 52.2%-53.3%) for patients with metastatic cancer. Kaplan-Meier 5-year survival was 54.6%(95% CI, 54.2%-55.1%) for patients with CKD, 76.6%(95% CI, 76.3%-76.8%) for patients with nonmetastatic cancer, and 33.9%(95% CI, 33.3%-34.4%) for patients with metastatic cancer. Compared with nonmetastatic cancer, the age-, sex-, and comorbidity-adjusted relative rate of death was similar for CKD (adjusted relative rate, 1.00; 95% CI, 0.97-1.03; P = .92) during the first year of follow-up and was higher for CKD at years 1 to 5 (adjusted relative rate 1.23; 95% CI, 1.19-1.26). During the first year of follow-up, for patients with CKD, adjusted rates of placement in long-term care (adjusted relative rate, 0.88; 95% CI, 0.82-0.94) and hospitalization (adjusted relative rate, 0.65; 95% CI, 0.64-0.66) were lower than rates for patients with nonmetastatic cancer; however, those rates were higher for the CKD group than for the nonmetastatic cancer group during years 1 to 5 (long-term care placement, adjusted relative rate, 1.36; 95% CI, 1.29-1.43; hospitalization, adjusted relative rate, 1.55; 95% CI, 1.52-1.58). As expected, adjusted rates of long-term care placement and hospitalization were higher for patients with metastatic cancer than for the other 2 groups. CONCLUSIONS AND RELEVANCE In this study, mortality, hospitalization, and likelihood of placement into long-term care were similar for CKD and nonmetastatic cancer. These data highlight the importance of CKD as a public health problem.