The haemoglobin disorders are common and treatable, and all couples at risk of having affected children can be detected by carrier screening, counselled, and given the option of prenatal diagnosis. This EC Concerted Action aimed to develop means to evaluate treatment and prevention in order to improve service delivery.
Haemoglobin disorders are common and treatable, and all couples at risk of having affected children can be detected by carrier screening, counselled, and given the option of prenatal diagnosis. This European Community Concerted Action developed means to evaluate treatment and prevention in order to improve service delivery. The feasibility of establishing and regularly updating registers of patients and prenatal diagnoses, and their value as tools for service audit was explored.
In most countries it proved feasible to set up patient registers, though this was more difficult for sickle cell disease than for beta thalassaemia. Most patient registers are still incomplete, but they have already demonstrated the value of the approach. It also proved feasible to make complete registers of prenatal diagnoses.
Collected figures show more known patients with haemoglobin disorders, and more affected births, in the north than in the south of Europe: the majority of those in the north have sickle cell disease, the majority in the south have thalassaemia. Data on deaths show greatly improved patient survival, related to regular treatment with the iron chelating agent Desferal.
The majority of informed couples at risk for thalassaemia, and about half those at risk from sickle cell disease, request prenatal diagnosis and selective abortion of affected pregnancies. Since these services have become available (in all countries) the number of affected births has fallen by over 75% in Italy and Greece, but the fall has been much less in the north. Enquiries into the circumstances surrounding new affected births show that in the majority of cases the parents had not been informed of the risk, and so had not had the option of prenatal diagnosis. There is evidence that access to the services by the population at risk is greatly improved by the availability of trained genetic nurses or counsellors.
Public health approaches to inherited disease are relatively poorly developed, despite steady progress in methods for detecting carriers of inherited disorders, and in patient care. The haemoglobin disorders (the thalassaemias and sickle cell disease) provide a model for developing such approaches as they are common, treatable, and preventable on a population scale. This project arose from a WHO-sponsored survey of the epidemiology of and services provided for these disorders in Europe, which revealed great unevenness of service delivery between and within European countries.