Intended for healthcare professionals


People with intellectual disabilities

BMJ 2004; 329 doi: (Published 19 August 2004) Cite this as: BMJ 2004;329:414
  1. Sally-Ann Cooper, professor of learning disabilities (SACooper{at},
  2. Craig Melville, senior lecturer in learning disabilities (cam13h{at},
  3. Jillian Morrison, professor of general practice (jmm4y{at}
  1. Section of Psychological Medicine, Division of Community Based Sciences, Gartnavel Royal Hospital, Glasgow G12 0XH
  2. Section of Psychological Medicine, Division of Community Based Sciences, Gartnavel Royal Hospital, Glasgow G12 0XH
  3. Section of General Practice, Division of Community Based Sciences, University of Glasgow, Glasgow G12 9LX

    Their health needs differ and need to be recognised and met

    People with intellectual disabilities comprise about 2% of the UK population. Demographics are, however, changing and the population of people with intellectual disabilities increased by 53% over the 35 year period 1960-95, which equals 1.2% per year.1 A further 11% increase is projected for the 10 year period 1998-2008. These changes are the result of improved socioeconomic conditions, intensive neonatal care, and increasing survival. The health needs of people with intellectual disabilities have an impact on primary healthcare services and all secondary healthcare specialties.

    People with intellectual disabilities experience health inequalities compared with the general population. Although their life expectancy is increasing, it remains much lower than for the rest of the population.25 The standardised mortality ratio has been found to be 8.4 for people with severe intellectual disabilities in United States and 4.9 for people with intellectual disabilities of all levels in Australia.4 5 Additionally, people with intellectual disabilities have higher levels of health needs than the general population,69 and these are often unrecognised and unmet.6 10 11 This contributes to ongoing health inequality, chronic ill health, and premature death. Many biological, psychological, social, and developmental factors, as well as life experience, contribute to this inequality. People with intellectual disabilities also experience access barriers in using health services.12

    People with intellectual disabilities have a different pattern of health need. For example, epilepsy, gastro-oesophageal reflux disorder, sensory impairments, osteoporosis, schizophrenia, dementia, dysphagia, dental disease, musculoskeletal problems, accidents, and nutritional problems are all much more commonly experienced.12 Conversely, health problems related to smoking, alcohol, and use of illegal drugs are uncommon.12 Some problem behaviours, such as self injury and pica, are specific to intellectual disabilities and may be associated with particular genetic syndromes. The commonest causes of death also differ.12 For the general population, the leading cause of death is cancer, followed by ischaemic heart disease, then cerebrovascular disease. For people with intellectual disabilities, respiratory disease followed by cardiovascular disease related to congenital heart disease are the leading causes of death, with cancer ranked lower. Their pattern of cancers is also different, with lower rates of lung, prostate, and urinary tract cancers, and higher rates of oesophageal, stomach, and gall bladder cancer and leukaemia.12

    Reducing health inequalities has been the focus of policy. However, current strategies are based on the health needs of the general population. As the pattern of health need and causes of death differ for people with intellectual disabilities, most current policies and public health initiatives will widen rather than close the health inequality gap.

    This is not the only group to experience health inequalities. For example, people from ethnic minorities or those living in poverty or areas of social deprivation also experience inequality. Some needs may be relevant across groups, such as improving accessibility of services. However, the extent of inequality is greater for people with intellectual disabilities than for other excluded groups, as shown by their standardised mortality ratio. This combined with the markedly different pattern and spectrum of health need (rather than just the excess of unmet health need) indicates a requirement for specific action. This may entail redistribution of finite healthcare resources and difficult decisions regarding competing interests.

    Developing guidelines can improve health by influencing policy, commissioning of services, and practice. However, guidelines can also unintentionally increase health inequalities.13 The amount of evidence relating to people with intellectual disabilities is less than for other groups, hence relevant issues are unlikely to be selected for development of guidelines. Assumptions are made that reports or guidelines apply to all members of the population, but panels are unlikely to have included expertise on the differing health needs of people with intellectual disabilities. Hence everyone benefits except people with intellectual disabilities. Similar unintentional discrimination can be found throughout the NHS in the United Kingdom.12 Further discrimination in Scotland is caused by the Adults with Incapacity (Scotland) Act 2000. This prohibits research with adults who do not have capacity to consent unless their nearest relative or welfare guardian consents, but almost no one has a welfare guardian, and many adults with intellectual disabilities have no contact with a relative.

    These inequalities and discrimination exist despite legislation explicitly outlawing discrimination—for example, the Australian Disability Discrimination Act 1992, the Americans with Disabilities Act 1990, the UK Disability Discrimination Act 1995, and the Human Rights Act 1998. These laws require services to make reasonable adjustments and accommodations. However, the reality is that legislation does not yet seem to have translated into improved health status for people with intellectual disabilities.

    We need to change these inequalities. High quality research needs to be supported to develop the evidence base. We need to ask obligatory questions during the development of every piece of work. “How might this affect specifically people with intellectual disabilities?” “Could it possibly disadvantage some people with intellectual disabilities?” “What additional supports or reasonable adjustments are required so that it equally benefits people with intellectual disabilities?” Additionally, the population with intellectual disabilities requires specifically targeted public health interventions.


    • Competing interests None declared.


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