20 year follow up and survival analysis in a cohort of patients with Haemoglobin E beta Thalassaemia.

Abstract

INTRODUCTION & OBJECTIVES: Haemoglobin E beta thalassaemia (EBT) is the commonest beta thalassaemia syndrome in the world and is extremely phenotypically variable. Unlike for transfusion dependent thalassaemia (TDT) there are no clear guidelines for the management of this disease. We have followed up a cohort of 109 patients with EBT for 20 years. Objective of the study was to study the 20-year survival and factors that affect survival. METHODS: Study was conducted at Kurunegala Thalassaemia centre. Transfusions were stopped in 1997 in all 109 patients. Since then they were assessed every three months by the clinical team for the next 20 years. Relevant haematological, biochemical, radiological assessments were done periodically. RESULTS: 32 (30%) of patients were dead at 20 years. Kaplan Meir survival curve identified the median survival to be 51 years. Splenectomy had been done in 73/109 (67%) patients. Splenectomy allowed 66% to be off transfusions even 9.7± 1.3 years post- surgery. However, 33% had to return to transfusions. The commonest cause of death in the cohort was infections (34.3%). Most (72%) infective deaths happened in those who were splenectomised. Transfusions needed to be restarted in 60%, of whom 33% went back to (>8 per year) regular transfusions at a mean 8.4 ±0.8 years after stopping transfusions. CONCLUSION: In this first ever long term follow up study of EBT, significantly shortened survival is observed. Though splenectomy allows prolonged transfusion free phases in many it increases risk of infective deaths. Overall the disease is far less benign than previously thought with a high prevalence of morbidity and mortality.