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Burrow N.R., Koyama A.K., Choudhury D., Yu W., Pavkov M.E., Nee R., Cheung A.K., Norris K.C., Yan G.: Age-Related Association between Multimorbidity and Mortality in US Veterans with Incident Chronic Kidney Disease. American Journal of Nephrology DOI 10.1159/000526254
It is well known that prevalent chronic kidney disease (CKD) is associated with excess morbidity and mortality compared to non-CKD. Few studies have examined this association in incident CKD.
Using an electronic health record database, Burrows and colleagues carried out a descriptive analysis of co-morbidity and mortality in a large cohort of nearly exclusively male patients (n = 892,005) receiving care in the US Veterans Administration (VA) facilities between 2004 and 2018. Incident CKD was defined by estimated glomerular filtration rate (eGFR) values only and occurred when the eGFR-creatinine (by the 2009 CKD-EPI equation, including the racial coefficient) fell below 60 mL/min/1.73 m2 for the second time at least 3 months apart, excluding CKD category 4–5. This cohort only included incident categories 3A or 3B. Urine protein excretion was not routinely collected; only 38% of the cohort had proteinuria (albuminuria) testing. Extensive co-morbidity and mortality data were collected. As expected, most subjects were elderly (average age at CKD incidence 72.3 ±9.9 years). Medication use was collected, but apparently not including statins. No data on a control group of non-CKD patients were included.
Multi-morbidity was very common (95% had 2 or more co-morbidities, averaging 4) and cardiovascular disease (CVD) morbidity was associated with high mortality among younger cohort members, while dementia was associated with higher mortality among older members of the cohort. A high burden of co-morbidity was especially indicative of a high mortality risk among the younger members of the cohort. Clearly, co-morbidity is of great concern among an incident CKD group of subjects. The lack of a “control” group without incident CKD is a weakness of this otherwise informative, descriptive study. One can only speculate how the results would have differed if a non-racially adjusted equation for eGFR had been used or if the definition for incident CKD had utilized an age-adapted criterion for eGFR-defined CKD. The lack of a systematic evaluation of albuminuria is a weakness the authors acknowledge. Such under-appreciation of the importance of albuminuria for assessing CVD risk is, unfortunately, common in many primary care settings. Nevertheless, despite its overt weaknesses, this is a useful descriptive study of the many challenges facing the care of patients with incident CKD (at least in American VA facilities).
