What is dual diagnosis?
(written by Helen Sheppard, DipSW)

There are many different definitions of the term ‘dual diagnosis’ and some debate over its usefulness (Rorstad & Checinski, 1996). Dual diagnosis is a misleading and unhelpful label but has commonly come to refer to the co-existence of a severe mental illness and substance use. In practice individuals rarely receive a formal diagnosis of both mental illness and substance misuse (Manley 1998).

One criticism is that the term focuses on medical problems and diagnoses when the reality is that people who suffer both mental ill health and problematic substance use often have multiple social problems (Barker, 1998; Bean, 1998).  People who present with these co-existing problems often face serious social disadvantages and therefore social workers have a crucial role in working with, and supporting, these people.

Evidence shows that people with a mental ill health and substance problems, compared to people with a mental health problem alone, are more likely to:

• have a higher risk of suicide
• have more severe mental health problems
• be homelessness or insecurely housed
• have an increased risk of being violent and being victimized
• have more contact with the criminal justice system
• suffer family problems and a history of childhood abuse
• slip through the net of care

They are also less likely to follow medication regimes and engage in other forms of intervention and treatment (Bannerjee et al. (2002).

The Department of Health (2002: 7) refers to the term covering a “broad spectrum of mental health and substance misuse problems that an individual might experience concurrently”.  Examples include a man with anxiety and depression who drinks alcohol for social confidence or the woman who uses heroin to help her to cope with hearing voices.

In addition some people’s mental health problems may have been induced by substance use, for example ‘amphetamine psychosis’ or ‘alcohol psychosis’.  What is difficult to determine is whether or not the person would have developed mental health problems anyway. (For further reading about theories and models of dual diagnosis see Rassool 2002.)

For more information on the relationship between particular substances and mental ill health go to http://www.rethink.org/dualdiagnosis/.

Working with both issues | Assessment issues | Treatment issues | Websites