1. Department of Geriatric Cardiology, the First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi, P.R. China
2. These authors contributed equally to the work and should be regarded as co-first authors.
3. Department of Evidence-based Medicine, the First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi, P.R. China
4. Department of Obstetrics and Gynecology, the First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi, P.R. China.