Symptoms and signs of β thalassaemia trait: results of the first comparative study

Abstract

OBJECTIVE: Thalassaemia trait is considered a mild and asymptomatic condition. However patients with this disease may be symptomatic. Should these be attributed to the disease? Does pre-knowledge about the diagnosis affect patients' symptoms? Previous studies were affected by the lack of a control arm. This is the first controlled study which compares symptoms of (3 thalassaemia trait with matched controls and also looks at how prior knowledge of the disease affects symptoms. DESIGN, SETTING AND METHODS: We administered a questionnaire to 146 individuals who knew that they had thalasseamia trait (Group 1} and to 248 "normal" volunteers who did not know their "thalassaemic status". Eleven symptoms were assessed. All individuals were examined by the same investigator and had a full blood count from an automated analyzer and a thalassaemia screening with High Performance Liquid Chromatography (HPLC- Bio Rad). RESULTS: The FBC and HPLC data showed that of the 248 "normal" controls , 63 had p thalassaemia trait (Group 2), and a further 96 had MCV< 80 and MCH <27 without thalassaemia (Group 3), presumably due to iron deficiency. 89 had normal red cell indices and normal HPLC (Group 4). Comparison of the four groups showed that "anaemic symptoms" like headache, exercise intolerance and lethargy occurred in significantly higher numbers in Groups 1 and 2 compared to Group 4. Comparison of Group 1 and Group 3 did not show any significant difference suggesting a similar mechanism for symptoms. Group 2 did not differ significantly from Group 1 in anyway. CONCLUSIONS: The p thalasseamia trait can be a symptomatic disorder and the symptoms arc those of anaemia. Symptoms are not affected or caused by being aware of the diagnosis.