Assessment of Anemia Prevalence Among Non-Pregnant Women in Urban Areas of Shanghai and Tokyo: A Retrospective Observational Study

Introduction: Anemia, one of the most common and widespread disorders in the world, is a public health problem, and among various causes, iron deficiency is the most common cause of anemia, affecting more than 2.2 billion people worldwide. In developing countries, insufficient dietary intake is a main cause whereas eating habits like vegetarian diet or avoidance of red meat is associated with anemia in developed countries. Shanghai has been sharing many characteristics with Tokyo not only in rapid economic growth and westernization but also in more volition on personal life and late marriage in women of child-bearing age. Here in this study, with the large-scale database in both areas, the prevalence of anemia was elucidated among non-pregnant women age in urban areas of representative Asian countries undergoing routine annual health checkups. Methods: All participants in this retrospective observational study were limited to women aged between 20 and 44. A total of 2,006 health checkup data (from May to September 2016) from residents of Xinqiao, Sheshan and Maogang towns in Songjiang District by stratified cluster sampling were collected. These three towns are located in the southwestern part of Shanghai and their population is approximately 230,000 in total. A total 877 health checkup data (from February to July 2017) from 1,087 employees in the dispensing pharmacies in Tokyo area were collected. Anemia was defined as a hemoglobin (Hb) concentration lower than 12.0 g/dL, which was further categorized as mild (10.0