A population health approach to rare disease – tools fit for purpose?

The significant burden on the health service and on the quality of life of a large number of Irish people caused by common diseases like heart disease, diabetes and cancer has driven a range of stakeholders to push for ever-more effective and comprehensive public health policies. These sorts of population health challenges are well established as the ‘bread and butter’ of public health policy-making. The full battery of population health tools in prevention, treatment and chronic disease management are employed. This has resulted in significant improvements not only in these disease areas but also in overall population health.

But what can be gained from a population health approach to rare diseases on the island of Ireland?

Population health burden – big or small?
The term ‘rare disease’ can, on the surface, give the impression that the overall burden of rare diseases to population health is small. The European definition considers a disease to be rare if it occurs with a prevalence of less than or equal to 5 per 10,000 European population. While each rare disease is indeed ‘rare’, there are over 6000 diseases considered rare so, in fact, rare disease patients form a rather large group. At European level, it is estimated that between 6 and 8 % of the population is affected by a rare disease. Applying this figure to the Republic of Ireland would produce a very rough estimate of 275,000 people.

Rare diseases are diverse but as a group they exhibit some common characteristics

-    around 80% of rare diseases are genetic in origin
-    the prevalence distribution of rare diseases is skewed – 80% of all rare disease patients are affected by just 350 rare diseases.
-    most rare diseases are life threatening or associated with significant disability
-    rare diseases are a significant contributor to the overall national level of physical, sensory and intellectual disability in children and adults
-    around 50 to 75% of all rare diseases affect children
-    all childhood cancers are considered rare diseases
-    around 30% of children with a rare disease die before their 5th birthday
-    rare diseases are responsible for 35% of deaths in the first year of life
-    around 11% of all paediatric hospital admissions are for children with genetic disorders and 18.5% are for children with other congenital malformations
-    late diagnosis, absent diagnosis or incorrect diagnosis are commonplace and have significant implications for those with treatable disease

Sources: EURORDIS, 2005; Ayme & Hivertleds, 2011; Posada de la Paz & Croft, 2010; NCMG, 2010; French National Plan on Rare Diseases 2004-2008. .

Taken as a group these characteristics imply a very significant mortality, disability and morbidity burden associated with rare disease.

How can public health contribute to reducing the burden of rare disease on the island of Ireland?

At European level, the experience of those countries where public health initiatives for rare diseases exist shows that a specific national approach and European collaboration can improve health and social outcomes for people with rare diseases.

It is really interesting  to then consider the fit between the ‘essential public health operations’ in the context of what is now understood about the population health burden of rare disease.

These ten established essential operations include epidemiological surveillance and assessment of population health; the identification of health problems and hazards, health protection and preparedness for public health emergencies. The low level of epidemiological knowledge on rare disease has been identified in both the French and Belgian national rare disease plans as a major obstacle to the development of evidence-based service planning. Disease prevention and health promotion are also viewed as essential public health operations and these would have particular relevance in the rare disease context in terms of antenatal care, congenital anomaly and genetic counselling. The monitoring of patient outcomes and quality of care including population screening also have an important role to play in informing appropriate service delivery for rare disease patients. Grass-roots public health work such as community needs assessment, patient group and community engagement, and facilitating effective cross-sectoral working are also vital to a strategic national approach. This is particularly relevant in the case of children and adults affected by disabling rare disease that affects many facets of their lives.   

The European Project for Rare Diseases National Plans Development (EUROPLAN), supported by the Programme of Community action in the field of Public Health, has developed resources to facilitate the establishment and implementation of National Plans in the field of rare diseases. Such plans or strategies are recommended to be established by the end of 2013.  Health authorities of 27 EU member states signed a document, stating their willingness to fulfil this deadline including Ireland and the UK.

The UK Rare Diseases Plan is due to be released for consultation shortly. Meanwhile, the Institute of Public Health is working to support the Department of Health develop a national rare disease plan for Ireland.