What is Comorbidity?

addiction and mental health

What is it all about?

Mental health problems and addiction commonly occur alongside each other. Bearing in mind that an addiction to alcohol or drugs is a mental health problem in its own right, the two together are sometimes referred to as ‘comorbidity’, or ‘dual diagnosis’ or ‘multiple morbidity’. Comorbidity is common because mental health problems are common and so are addiction problems but the mechanisms of how the two interact are not so straight forward.

Mechanisms of comorbidity...

➽ a primary psychiatric illness precipitating or leading to substance misuse

➽ substance misuse worsening or altering the course of a psychiatric illness

➽ intoxication mimicking or causing psychological symptoms

➽ dependence mimicking or causing psychological symptoms

➽ substance withdrawal syndromes leading to psychiatric symptoms or illnesses

➽ substance misuse and mental illness coexisting as two separate conditions by coincidence

➽ any combination of the above

⚠️ Misdiagnosis :: It takes an experienced practitioner to make the correct diagnosis and it is important to do so because…

  • There are complex symptom clusters to unravel

  • There is a need for accurate treatment planning

  • Service users want a clear explanation of their problem

  • It is important to have reliable statistical data

⚠️ Over-diagnosis :: Some questionnaires used to assess anxiety and depression are likely to give false positives if there is also a diagnosis of dependence. Sometimes practitioners make an incorrect diagnosis because they are unsure what to do if they correctly identify a problem.

Trauma - cause and effect

Addiction lifestyles and the drugs used are frequently associated with dangerous situations and accidents.

Trauma can result in the development addictive behaviour as a coping response.

Families of people with addiction problems commonly experience trauma resulting from financial difficulties, guilt, shame, fear and shock.

Children of addicted individuals experience neglect, abuse, guilt and shame.

Practitioners may experience secondary post traumatic stress as a consequence of handling other people’s trauma which may also trigger their own.

Trauma awareness needs to be part of the organisational culture.

Missouridou 2017

The difference between mental illness and mental health disorders

The experience of anxiety or depression or difficult personality characteristics all occur in the general population: these ‘normal’ experiences become labelled disorders only when they are severe or distressing (the disorder zone on the chart). This is in contrast to symptoms of psychosis or dementia which, in the main, are seen as ‘abnormal’ and not commonly experienced in the general population. It follows that psychosis and dementia are easier to identify and more properly seen as mental illness compared to the mental health disorders that are exaggerations of ‘normal’ experiences.

Both mental illness and mental health disorders may be related to substance use or have other causes.

The chart illustrates the difficulty in determining when the normal experience of anxiety, depression, or a personality trait becomes a mental health disorder. Take anxiety as the example: the chart shows that as anxiety increases (red bars) so a person functions better (green bars) up to a point where the anxiety starts to have a negative effect. Put another way, a bit of anxiety or being a bit of an obsessional person is a good thing but too much of it is not. Depression is somewhat different: mild symptoms may bring about new insights and a momentum for change and, in that sense, may improve functioning, but increasing symptoms of depression will quickly reduce a person’s daily effectiveness.

So, when does good mental health morph into a mental health disorder? The chart illustrates how the answer is inevitably an arbitrary one. Most important is that individuals will seek help, including self-help, if they are finding their mental health too distressing to cope with and so, at the point of self-identifying a problem, they can be seen to transition into having a disorder. Practitioners helping these individuals will have their own perspective on the severity of the problem, and therefore the intervention required, as well as taking account of any danger to other people.

It is useful for anyone with a responsibility for data collection to use a recognised classification system. Statistical health data in the UK are generated from the International Classification of Diseases, ICD–11, the global standard for systematic recording, reporting, analysis, interpretation and comparison of health data.

What is the treatment for comorbidity?

It is good practice for agencies to ensure that people with comorbidity are seen by a mental health practitioner who is competent to make an assessment. Rating scales are a good screening tool to indicate whether or not referral to a mental health practitioner is needed. They are not diagnostic and there should always be training in the interpretation of results.

For less severe problems, iSBNT is likely to be an effective intervention. For more severe problems a rule of thumb is for iSBNT to be the intervention for the substance misuse supplemented by the standard treatment for the mental health problem but only where the severity or complexity of the problem demands specialist input. Combinations of different patterns of substance use with the whole range of mental health problems and disorders come under the umbrella of comorbidity. It follows that there can be no one treatment for comorbidity.

What to look out for and who to involve…

  • Delirium is an emergency to be dealt with by the Accident and Emergency department of the local hospital. If caused by thiamine deficiency then immediately give parenteral vitamins or, if unavailable, refer to the Accident and Emergency department.

  • Psychosis requires immediate referral to a mental health emergency clinic or for psychiatric assessment.

  • Dementia requires referral to psychiatric services.

  • Anxiety if not related to obvious ups and downs of life will best be dealt with by a mental health practitioner who can deliver CBT and relaxation techniques suited to anxiety. Panic attacks will need immediate help.

  • Depression if not related to obvious ups and downs of life will best be dealt with by a mental health practitioner who can deliver CBT and pharmacotherapies. Suicidal thoughts or self-harm need immediate re-assessment for possible referral to emergency psychiatric services.

  • Trauma if causing distress will best be dealt with by a mental health practitioner who can deliver CBT or Eye Movement Desensitisation and Reprocessing (EMDR).

  • Personality disorder especially with problems of emotional regulation will best be dealt with by a mental health practitioner who can deliver DBT.

Providing comorbidity services poses particular challenges…

  1. For service users substance use can ameliorate mental health problems and in turn exacerbate them; services may be fragmented making it difficult to engage with different agencies and therapists.

  2. For practitioners there is a need for specialist training to develop the necessary skills, and for the support and supervision needed to deal with comorbidity problems.

  3. For agencies there is a need to ensure suitably trained and experienced staff are available, and to overcome barriers of multi-agency working where there may be little communication and a different ethos.

In this video Rebecca Lee talks about…

  • Drug use and mental illness found in different services

  • The relationship between drug use and mental illness

  • Whether to deal with substance use and mental illness together

  • Treatment and risk management

  • Referral to specialist services

Dr Rebecca Lee is a Consultant Addiction Psychiatrist

What is is the Quadrant model and why is it important?

The fragmentation of addiction services has resulted in a common complaint from service users that they have to attend several different services, with the same questions being asked and sometimes a lack of clarity as to which service is doing what. The Quadrant Model is a useful way of avoiding this. It describes four presentations of comorbidity allocated by low and high substance use severity crossed with low and high severity of mental health. Each quadrant requires one service to provide the care package or at least to be the lead, seeking advice and support from the other services as needed. Where there are a number of addiction services that can do this then any can be the ‘first port of call’. The model…

  • Flags the appropriate agency for help seekers at the point of referral

  • Makes clear which agency has responsibility for co-ordinating care

  • Minimises unnecessary multiple referrals

  • Indicates the skill mix required by services providing comorbidity care

What goes in each box of the Quadrant?

Which disorders go into each quadrant is a matter for consultation and agreement between services - the point is that there needs to be a truly collaborative local way of working. Here are some points to consider…

  1. Where there is a diagnosis of mental illness such as schizophrenia or bipolar, then a mental health team will need to take the lead role and will need support from an addiction team to help minimise the impact of the substance use on the course and the treatment of the mental illness.

  2. Where there is a drug or alcohol induced illness such as psychosis, then this is likely to resolve with treatment of the substance use and so an addiction comorbidity team would be best placed to take the lead role and provide the treatment.

  3. Where a mental health disorder such as anxiety or depression antedates the addiction problem then it is less likely to resolve alongside resolution of the drinking or drug taking, albeit there will be improvements. If the disorder post-dates the addiction then it is more likely to resolve with a period of abstinence or at least stable substance use and so any addiction service could provide the treatment or in more severe cases an addiction comorbidity team.

A good treatment for addiction problems and co-existing mild to moderate mental health symptoms is Social Behaviour and Network Therapy. The art of comorbidity treatment is to understand how the disorders are interwoven and feeding off each other, and make adjustments to standard treatment accordingly.

More pages about comorbidity