Prevalence of and factors related to anemia among Japanese adult women: Secondary data analysis using health check-up database

The issue of anemia is important in terms of a woman's preconception health. This study aimed to conduct an exploratory investigation of the prevalence of and factors related to anemia in non-pregnant Japanese women. Secondary data analysis was conducted using a database of women aged 20-49 years old who had attended an annual health check-up at a hospital in Tokyo (n = 10,598). A multiple logistic regression analysis was performed to identify factors related to anemia in two age groups: women aged 34 and under and those aged 35 and over. Anemia was defined as hemoglobin concentration levels <12.0 g/dL. The overall proportion of women with Hb <12.0 g/dL was 17.1%. Women aged 35 and over with a current medical history of uterine myoma were found to be at a higher risk of anemia. Women aged 35 and over who were overweight had a lower risk of anemia than women with normal weights. Current and past smoking habits affected hemoglobin levels among women aged 35 and over. In both age groups, those who drank alcohol habitually were at a lower risk than those who did not. Related factors of anemia should take into consideration a woman's age and lifestyle.