Prevalence studies have indicated that people with learning disability (mental retardation) are at significantly higher risk of developing psychiatric and behavioural disorders. This is one of the main reasons for the failure of community placements. With the promotion of the concept of normalisation and integration, patients' mental health needs are increasingly acknowledged by our community. This paper focuses on the development and provision of specialised psychiatric services for people with the dual diagnosis of learning disability and psychiatric problems. The models of service delivery and resource implications are discussed, with overseas figures quoted for reference. A hospital-based system with multidisciplinary input and strong community ramifications is recommended for the local setting in Hong Kong.
Keywords: Community, Learning disability, Psychiatric service
History tells us that the 'medicalisation' of learning disability (mental retardation) probably started as early as the 17th century, and 'psychiatrisation' by the 19th century. (1) However, most psychiatrists later lost interest in this field and learning disability almost disappeared from the psychiatric scene. This was partly due to the therapeutic pessimism that followed the developments in neuropathology which saw learning disability as an incurable brain disorder and partly due to the domination in psychiatry by psychoanalysis that saw normal intellectual and language abilities as a prerequisite to successful treatment. As a result, the progress in this branch of psychiatry was slow until the past 2 to 3 decades when there was a reactivation of psychiatric enthusiasm in this area.
The resurgence of interest is firstly attributed to the general recognition of the right of people with learning disability to appropriate care in both physical and mental health. Secondly, the concept of normalisation has become widely accepted. People with learning disability are expected to live in the community and to use community facilities. Poor mental state is one of the major reasons for the failure of their integration into the community and this could mean further rejection and social discrimination. At the same time, the role of psychiatrists has also changed dramatically during the past 20 years, from simply making the diagnosis and the administration of residential facilities to more active and direct clinical involvement, including the treatment of psychiatric and behavioural disorders, promotion of mental health, family intervention and contribution to planning and management of services.
RISK FACTORS FOR PSYCHIATRIC PROBLEMS
Individuals with learning disability are at higher risk of developing mental health problems. There are many factors to account for this increased vulnerability, including:
* Brain damage resulting in learning disability may also predispose the individual to mental disorder.
* Some syndromes are known to be associated with behavioural abnormalities and psychopathology. For example, Down's syndrome has been associated with early onset of Alzheimer's disease and Lesch-Nyhan syndrome is associated with self-injurious behaviours.
* Low self-image and chronic frustration caused by repeated failures and multiple disabilities.
* Limited repertoire of coping strategies and defence mechanisms.
* Stigmatisation, rejection, and social isolation.
* Inappropriate expectation, and inconsistent care or overprotection by multiple carers.
* Poor access to community resources resulting in a restricted and disadvantaged lifestyle.
SCALE OF THE PROBLEM: THE POPULATION TO BE SERVED
People with learning disability are growing in number. Children who might have died in infancy now survive to adulthood, and adults are living longer because of better living conditions and more advanced health care. …