Association of Anemia in Nondialysis CKD with Health-Related Quality of Life and Clinical Outcomes

The prevalence of anemia, a common complication of chronic kidney disease (CKD), increases with disease progression. Symptoms associated with CKD-related anemia include fatigue and weakness, contributing to a lower health-related quality of life and physical functioning among individuals living with nondialysis-dependent CKD compared with the general population.

The links between anemia, physical activity, health-related quality of life, progression of CKD, and mortality in patients with moderate-to-severe CKD have not been fully established. Junichi Hoshino, MD, PhD, and colleagues utilized data from the CKD Outcomes and Practice Patterns Study to identify associations between hemoglobin and health-related quality of life and physical activity, as well as associations between hemoglobin and physical activity and progression of CKD and mortality in patients with stage 3-5 nondialysis CKD. Results of the study were reported online in the Journal of Renal Nutrition [doi.org/10.1053/j.jrn.2019.11.003].

The study utilized prospectively collected data from 2121 patients with nondialysis CKD. Eligible patients were ≥18 years of age and were treated at 43 nephrologist-run clinics in Brazil and the United States participating in the CKD Outcomes and Practice Patterns Study. Cross-sectional associations were assessed of hemoglobin levels with health-related quality of life and physical activity levels. The study also assessed the association between hemoglobin and levels of physical activity with progression and all-cause mortality. Linear, logistic, and Cox regression analyses were adjusted for country, demographics, smoking, estimated glomerular filtration rate, serum albumin, very high proteinuria, and 13 comorbidities.

In patients with severe anemia (hemoglobin <10 g/dL), health-related quality of life was worse relative to patients with hemoglobin >12 g/dL; health-related quality of life was also worse in patients with mild-to-moderate anemia (hemoglobin 10-12 g/dL) relative to those with hemoglobin >12 g/dL. At hemoglobin levels >12 g/dL, the odds of being highly physically active were substantially greater.

There was a strong association between lower hemoglobin and greater progression of CKD and mortality; the association remained robust even following extensive adjustment.  There was a strong association between physical inactivity and greater mortality, and there was a weak association between physical inactivity and progression of CKD.

In conclusion, the researchers said, “This multicenter international study provides real-world observational evidence for greater health-related quality of life, physical activity, lower CKD progression, and greater survival in nondialysis-CKD patients with hemoglobin levels >12 g/dL, exceeding current treatment guideline recommendations. These findings help inform future studies aimed at understanding the impact of new anemia therapies and physical activity regimens on improving particular dimensions of nondialysis-CKD patient well-being and clinical outcomes.”