A mild decrease of renal function is related to increased hemoglobin level during 5-year follow-up period

BACKGROUND/AIMS: We analyzed chronological changes in hemoglobin according to renal function changes over a 5-year follow-up period. METHODS: We enrolled 5,266 adults with a glomerular filtration rate (GFR) > or = 60 mL/min/1.73 m2 at an initial examination at a routine health check-up; a follow-up examination was conducted 5 years later. We categorized the subjects according to GFR ratio (groups 1, 2, and 3, defined as GFRratio > or = 1.00, 0.75 to 0.99, and or = 90 mL/min/1.73 m2 at the initial examination (all p or = 60 mL/min/1.73 m2, a mild decrease in GFR over a 5-year follow-up period was associated with an increase in hemoglobin levels.