Androgen deprivation therapy and the risk of iron-deficiency anaemia among patients with prostate cancer: a population-based cohort study

Objectives The administration of androgen deprivation therapy (ADT) to patients with metastatic prostate cancer might be associated with some adverse effects such as anaemia; however, few studies have been performed in East Asian populations. This study aimed to investigate the association between ADT and iron-deficiency anaemia (IDA) among patients with prostate cancer in a population-based nationwide cohort. Design Cohort study. Setting Taiwan. Participants Data for the cohort study were retrieved from the Taiwan National Health Insurance Research Database. Propensity score matching was used to select 7262 patients with prostate cancer who received ADT as the study group and 3631 patients who did not receive ADT as the control group. Primary and secondary outcome measures This study individually tracked patients over a 3-year study period and identified those who were subsequently diagnosed with IDA following the index date. Results The incidence rates of IDA in the study and control groups were 1.66 (95% CI CI 1.45 to 1.86) and 1.01 per 100 person-years (95% CI 0.78 to 1.25), respectively. Furthermore, proportional Cox regression revealed an HR of 1.62 (95% CI 1.24 to 2.12) for IDA in the study group after adjusting for patients' age, monthly income, geographic location, residential urbanisation level and incidence of hyperlipidaemia, diabetes, hypertension, coronary heart disease, inflammatory bowel disease, other cancers and gastrointestinal bleeding. Conclusion Compared with its non-use among patients with prostate cancer, ADT use was associated with a higher risk of IDA.