Dual diagnosis

Dual Diagnosis (DD) is defined by the HSE as ‘the co-morbid disorders due to substance use and/ or addictive behaviours along with the presence of mental disorder(s)’.[i] Put simply, dual diagnosis is the co-occurrence of substance misuse and mental health problems. The disorders of substance use include disorders of alcohol use.

Dual diagnosis is now considered to be more the norm than the exception. Research shows that many people seeking help for addiction problems also present with complex needs and are struggling with anxiety and/ or depression or other serious mental health problems.[ii] Evidence indicates that 30-50% of people with severe mental illness have co-existing substance use problems, and the same study outlined that 85% of those attending an alcohol service had reported suffering from a psychiatric disorder in the previous year.[iii] Indeed, those with dual diagnosis are at increased risk of suicide compared to those with only substance-use or mental disorders.[iv]

A HSE report on dual diagnosis highlighted that co-morbid disorders present many challenges for health care professionals and services, is difficult to treat, and also has poorer outcomes such as increased risk of suicide and self-harm, higher rates of hospitalisation, longer duration of admission and increased risk of violence and offending. 

Dual Diagnosis is well known to be associated with poor outcomes due to the absence of, or limited level of services to cater to the complex needs of those with substance misuse and mental health problems.[v] For many years Alcohol Action Ireland has advocated that mental health – and indeed addiction treatment services  – take a ‘no wrong door’ approach to this issue and provide trauma-informed services for people with dual diagnosis and all alcohol-related problems.  

It is hoped this will now change following the publication of the HSE Model of Care for Dual Diagnosis developed by the National Working Group under the National Clinical Programme for Dual Diagnosis and endorsed by the College of Psychiatrists of Ireland.

While these are very welcome developments, concern remains that people with both problems will be excluded from getting an integrated service. This is because, depending on their location in the country, people who need both interventions still will not have access to the new service. Work in the area of dual diagnosis now needs to move towards the practical delivery of comprehensive services and a rapid extension of HSE work in this area.