[Detection of Red Blood Cell Life Span and Analysis of Influencing Factors in Female Blood Donors]

To determine the red blood cell life span (RBCS) in female blood donors using a carbon monoxide (CO) breath test and analyze the influencing factors of RBCS.

Female blood donors who donated whole blood at Fujian Blood Center from December 2023 to June 2024 were collected, and RBCS was measured using a CO breath test. The donors were grouped by age and body mass index (BMI), and hematological parameters were analyzed to establish 95% confidence interval. The donors were categorized into ferritin decline group and normal ferritin group based on their iron status, and the RBCS difference between the two groups were compared. The correlation between RBCS and iron metabolism indicators was analyzed and followed by linear regression analysis.

The distribution of RBCS in 365 female blood donors was skewed. There were no significant differences in RBCS between different age groups and different BMI groups (P >0.05). The 95% confidence interval for RBCS was 67.7-173.2 days. The RBCS of ferritin decline group was 115.1(96.9,133.5) days, which was significantly longer than 107.1(88.5,127.7) days of normal ferritin group (P < 0.05). RBCS was significantly negatively correlated with serum iron and transferrin saturation (r =-0.412, -0.431), and positively correlated with unsaturated iron binding capacity (r =0.348). The multiple linear regression analysis of RBCS indicated that, in addition to hemoglobin and endtidal carbon monoxide, serum iron was also an important factor affecting RBCS (P < 0.05).

As the availability of iron decreases, RBCS is prolonged, which may be an early compensatory response to iron deficiency in the body.