Clinical and health-related quality of life outcomes of transfusion-dependent thalassaemia patients in Singapore

Introduction: Transfusion-dependent thalassaemia is associated with complications related to iron overload from frequent red cell transfusions which affect quality of life. We collected data on the clinical outcomes, complications, socioeconomic status and health-related quality of life (HRQoL) of transfusion-dependent thalassaemia patients in Singapore, and analysed the associations between clinical and socioeconomic factors with development of transfusion-related complications and HRQoL scores. Materials and methods: This was a cross-sectional study of transfusion-dependent thalassaemia patients treated at four major public hospitals in Singapore. Clinical information was obtained from retrospective reviews of medical records. Socioeconomic data and patient-reported compliance to iron chelators were obtained from prospective interviews of patients or caregivers using a questionnaire. A validated, disease-specific HRQoL instrument, the TranQOL, was administered to patients and caregivers during a routine clinic or transfusion visit. Results: Liver iron loading was the most common transfusion-related complication and occurred in 79% of patients. Cardiac iron loading was noted in 28.3% and endocrine complications were present in 34.2%. Liver iron loading was significantly associated with higher mean ferritin level. Cardiac iron loading was significantly associated with increasing age, higher mean ferritin level and type of iron chelator. Endocrine complications were associated with increasing age, higher mean ferritin level, type of iron chelator and poorer patient-reported compliance to iron chelators. The lowest TranQOL scores were reported by caregiver parents of patients aged less than 18 years. Lower TranQOL scores were significantly associated with increasing age, especially in the 31-50 age cohort, and with reception of social assistance. Conclusion: The main morbidities noted in transfusion-dependent thalassaemia patients in Singapore are from complications associated with iron loading. The cohort of older thalassaemia patients aged 31-50 experienced significantly higher rates of cardiac iron loading, endocrine complications and lower TranQOL scores compared to younger age cohorts.