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EPIDEMIOLOGY of Non-Transfusion Dependent Thalassaemias: An Emerging Global Concern 25 OCTOBER 2012. Painting by: Loizos Loizou. For β- thalassaemia major: Identification and recognition of essential components for effective CONTROL strategies;
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EPIDEMIOLOGY of Non-Transfusion Dependent Thalassaemias: An Emerging Global Concern 25 OCTOBER 2012 Painting by: Loizos Loizou
For β-thalassaemia major: Identification and recognition of essential components for effective CONTROL strategies; II. Significant advances and initial optimistic outcome of research on FINAL CURE; III. From childhood fatal disease to a chronic one with high survival rates and good quality of life; IV. POLITICAL COMMITMENT – PREREQUISITE – NATIONAL PROGRAMMES LIMITED GLOBALLY. Prevention Management
Haemoglobin disorders, beyond β-thalassaemia major – most prevalent in the developing world • Under-recognition of clinical importance of other Hb Disorders: • β-thalassaemia intermedia and α-thalassaemia; • abnormal (or variant) haemoglobins, and; • combined forms. • Recognition of the problem and its magnitude came from improvements • (in more recent years) of: • Health Infrastructures; • Nutrition; • Public Health Sector: • Communicable diseases prevention; • Reduced Infant Mortality rates/ Under 5-years of age of mortality; • Policies for Non-Communicable diseases (WHO Strategic Plan) • Adoption of one WHA (WHA59. R20) and one EB (EB118.R1) resolutions • on SCD and thalassaemia and Haemoglobin disorders, respectively • EPIDEMIOLOGIC TRANSITION
The Story Beyond β-thalassaemia major – Milder Phenotypes • IMPROVEMENTS AT NATIONAL LEVEL HAVE ALLOWED: • BETTER SURVIVAL - PREVIOUSLY DIED UNDIAGNOSED/ • MISDIAGNOSED • REGIONAL AND GLOBALCOLLABORATIONS HAVE STRENGTHENED • OBSERVATIONS, STUDIES AND COMPILATION OF INFORMATION: MOLECULAR BASIS, GENETIC BACKGROUNDS NATURAL HISTORY AND CLINICAL PHENOTYPES.
BEYOND TRANSFUSION DEPENDENT THALASSAEMIAS – MILDER FORMS Primary forms include: • β-thalassaemia intermedia • Hb E/β-thalassaemia • Hb H disease, and • Combined forms (Extensive interactions between different Hb genes). • Molecular studies and genotype/phenotype work have confirmed - in recent years: • Extensive phenotype variation from mild to moderate to severe TRANSFUSION DEPENDENCY C.K.Li – 1st Pan-South China Workshop – Nanning 2012
P. Fucharoen – 1st Pan-South China Workshop - Nanning September 2012
β-thalassaemia intermedia β-thalassaemia intermedia “severe”β-thalassaemia intermedia
EPIDEMIOLOGY: • 7,000,000 children are born annually with either a congenital abnormality or genetic disease; • Up to 90% of the births occur in Low and medium • Resourced countries; • Approximately 25% are comprised of five (5) disorders: • two (2) of which are the monogenic diseases: • Inherited Haemoglobin disorders • & • G-6-P Dehydrogenase Deficiency 64TH WORLD HEALTH ASSEMBLY – May 2011
World map of Hb disorders 7% of the global population are carriers of an abnormal Haemoglobin (Hb) gene (World Bank 2006, report of a joint WHO – March of Dimes meeting 2006)
EPIDEMIOLOGY: • It is estimated that about: • 7% of the global population carriers a pathological Haemoglobin gene; • In excess of 300,000 children with either thalassaemia or sickle cell disease are born annually; • > 80% of annual homozygous births occur in Low- and Medium Resourced Countries; • > 80% are affected with Sickle Cell Disease – About 70,000 with thalassaemia of highly variable clinical course and depending on the mixture of inherited alleles; • > 80% of SCD patients die annually • For β-thalassaemia major age distribution, carrier rates, anticipated births and • number of registered patients: reflect lack of or suboptimal prevention and • management strategies – NO DATA OR ESTIMATIONS FOR MILDER PHENOTYPES WHO-TIF Joint Meeting - 2007
Stock of foreign-born in selected EU countries and the US between 1997 and 2006
MIGRATIONS HbE β-Thal.
Survival by 10-yr birth cohort, all UK 1975-84 1965-74 1955-64 ALIVE (%) Before 1955 Modell et al., Lancet 2000; 9220:2051-2
Ethnicity and region of residence Thal UK Thalassaemia register, 2002
Newborn Screening Programmes • Haemoglobinopathies - a public health concern in UK • 7.1% (4.2 million) of UK population “at risk” • 10% of UK births from “at risk” group
Ethnicity and Year of Birth of Current UK Thalassaemia patients UK Thalassaemia register 2002
EPIDEMIOLOGICAL WORK IS NEEDED: • BETTER SUPPORT AND STRENGTHEN PROGNOSIS; • DEVELOP APPROPRIATE MANAGEMENT AND • MONITORING PROTOCOLS; • GUIDE POLICY MAKERS TO PLAN AND DEVELOP • APPROPRIATE SERVICES, INCLUDING REGISTRIES • SUPPORT OF COMPILATION OF MORE ROBUST • INFORMATION ON NATURAL HISTORY, MEDICAL • COMPLICATIONS, MORBIDITY AND MORTALITY • RATES CONTRIBUTING TO THE • GLOBAL DISEASE BURDEN OF DISORDERS