RESUMO
AIMS: To investigate the prevalence, treatment status, and effect of anemia on medical costs, quality of life (QOL), and productivity loss in Japan. METHODS: This cross-sectional study used a database containing claims, health check-ups, and questionnaire data. Adults with hemoglobin data at 2020 check-ups were included. QOL and productivity loss were evaluated using EuroQol 5-Dimension (EQ-5D) and Work Productivity and Activity Impairment questionnaire data available for a subset of the population. Nationwide anemia prevalence, including both diagnosed as having anemia and undiagnosed but with low hemoglobin levels, were estimated. Treatment status was described by hemoglobin levels. Differences in medical costs, QOL, and productivity loss were compared between individuals with and without anemia. Subgroup analyses were performed using the Charlson Comorbidity Index (CCI). RESULTS: The study population included 554,798 individuals. Anemia prevalence was estimated at 15.1% with 55.3% undiagnosed. In patients with anemia, 85.3% were untreated; 79.5% of the treated patients received only oral iron drugs. In patients with anemia, monthly medical costs were ¥17,766 higher, EQ-5D score was 0.0118 lower, and productivity loss was 2.6% higher than in those without anemia. The trends were consistent even in limited patients with CCI = 0. Nationwide annual excess medical costs, deficit QOL, and productivity loss in patients with anemia were estimated at ¥3.32 trillion, 138,000 quality-adjusted life-years, and ¥1.13 trillion, respectively. LIMITATIONS: As the study population only included individuals who underwent health check-ups, they may be healthier than general population. Whether the differences in medical costs, QoL, and productivity loss are caused by anemia or other underlying differences in patient characteristics is unclear, given the likelihood of residual confounding. CONCLUSIONS: The results suggest that more than half of patients with anemia were undiagnosed and untreated. Patients with anemia had higher medical costs, lower QOL, and greater productivity loss than those without anemia.
