The patient population
Allergic conditions are extremely common – up to 30% of the population may be affected, with a higher prevalence in younger age groups. Most people affected have mild disease and may not require the services of an allergy specialist.
The treatment of patients with allergy has evolved over recent years. Developments include the introduction of anti-IgE monoclonal antibodies for certain types of urticaria, and the increasing availability of evidence-based immunotherapy. These have led to a need to change the types of service offered, so that as well as the traditional clinical model of a one-stop shop for diagnosis and advice, patients are also attending for regular treatment therapies.
In addition to patients who have allergic conditions, a substantial number of people referred to allergy services will not be diagnosed as having an allergy. This group of patients (in whom allergy is excluded), comprise about 30% of the current workload in adult allergy clinics but would not be reflected in a population survey of people who have allergies. Exclusion of allergy is an essential part of the service that should be considered in service design.
Prevention of disease
Allergy involves sensitisation to external agents. The rise in the numbers of people with allergy can be linked to improved public health, clean water supplies and living cleaner healthier lives. There is evidence to show reduced exposure to micro-organisms has led to the emergence of the allergic phenotype.
There is also emerging evidence that dietary strategies may mitigate the incidence of food allergy, eg the early introduction of peanuts may reduce the chance of an at-risk child developing clinical nut allergies. Allergy specialists need to engage with relevant research programmes and then act as advocates for changes in policy where new evidence emerges.
The other main risk factor for allergies and asthma is maternal smoking. This links with other specialties and national policy on smoking control.
Planning effective services
The BSACI Standards of Care Committee (SOCC) conducts national audits of allergy practice and prepares guidelines to support the implementation of best clinical practice.
Each clinical commissioning group is expected to commission appropriate services for patients with allergic conditions. However, the shape of these services will vary from place to place to a greater degree than for services that are commissioned and provided in all hospitals. The patchy distribution of current allergy services means that there is a variety of service delivery models. The general direction of travel is for hub-and-spoke arrangements, with the central hub providing leadership and support for its satellite services. Clinical governance and subregional services may be led by the hub, with regular meetings between providers to ensure effective awareness and dissemination of expertise, and updating of relevant protocols.
The next decade will see the need for specialist allergy services increase further. This will be partly due to a continuing increase in prevalence of allergic conditions, but also because new targeted therapies will develop from current research into mainstream therapeutic use. Food desensitisation is one such intervention, which is showing promise as a way to reduce the likelihood of reaction to small exposures of foods.