Prevalence of anemia in patients with chronic kidney disease attended at a nephrology outpatient clinic and its association with the outcome of renal replacement therapy over five years: a retrospective cohort study, Municipality of São Paulo, 2010-2018.

The prevalence of anemia at admission among patients with chronic kidney disease at a nephrology outpatient clinic was 41.8%.

• The study included 534 patients admitted to a nephrology outpatient clinic in São Paulo between 2010 and 2018.
• Anemia was defined as hemoglobin concentration <13 g/dL for men and <12 g/dL for women.
• This was described as a 'high prevalence of anemia in chronic kidney disease' in patients referred from Primary Health Care.

Hypertension and diabetes were the leading causes of chronic kidney disease in the study population.

• Hypertension accounted for 35.2% of CKD etiologies.
• Diabetes mellitus accounted for 27.5% of CKD etiologies.
• These were identified from demographic and clinical data analyzed using frequencies and absolute values.

4.1% of patients progressed to renal replacement therapy over five years of follow-up.

• The outcome of renal replacement therapy was assessed over a five-year period.
• The study cohort consisted of 534 patients admitted between 2010 and 2018.
• Progression to renal replacement therapy was compared between patients with and without anemia at admission.

Anemia at admission was associated with a significantly higher risk of progression to renal replacement therapy over five years.

• Hazard ratio (HR) for anemia at admission was 3.24 (95% CI 1.38–7.61).
• This association was identified using Kaplan-Meier curves with log-rank test and Cox regression survival analysis.
• Patients with and without anemia at admission were compared for clinical data and need for renal replacement therapy over five years.

Hemoglobin level was an independent predictor of progression to renal replacement therapy.

• HR for hemoglobin level was 0.766 (95% CI 0.593–0.989), indicating that higher hemoglobin was associated with lower risk of the outcome.
• This was identified through Cox regression survival analysis.
• Hemoglobin level was described as 'an independent variable associated with the outcome.'