# Factors associated with the SARS-CoV-2 immunoglobulin-G titer levels in convalescent whole-blood donors: a Chinese cross-sectional study

## TL;DR

This study finds that BMI, smoking, and exercise affect IgG antibody levels in male SARS-CoV-2 convalescent blood donors, but not in females.

## Contribution

Identifies gender-specific factors influencing IgG titer levels in convalescent blood donors for potential donor screening optimization.

## Key findings

- BMI, smoking, and exercise frequency predict IgG levels in male convalescent donors.
- These factors do not predict IgG levels in female convalescent donors.
- Findings may help optimize donor selection for treating severe or immunocompromised patients.

## Abstract

Blood transfusions from convalescent Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infected patients could be used to treat patients with severe infections or immunocompromised patients. However, it is necessary to select the optimal donors to maximize the utilization of resources. In this study, we investigated the associations among body mass index (BMI), tobacco smoking, exercise frequency and duration, and alcohol consumption with the SARS-CoV-2 immunoglobulin-G (IgG) antibody titer levels with in the Chinese convalescent blood donor population. Here we show that BMI, smoking habits, and exercise frequency appear to be predictive factors for IgG levels in convalescent male blood donors. However, these variables were not observed as predictive of IgG levels in female convalescent blood donors. The findings could be used to optimize the screening for potential blood donors to treat immunocompromised or severely ill COVID-19 patients.