Comorbidity research
selected articles
How common is comorbidity?
Our opinion
All of the surveys below are about associations between mental health and addiction and do not imply causal links. The important thing to note is that comorbidity is not a single entity, rather there are many different combinations of substance use with mental health problems.
Surveys :: How common is comorbidity in the general population?
The Epidemiological Catchment Area Study in the US was conducted some time ago but is still one of the largest and most detailed surveys of comorbidity. 20,291 individuals were interviewed. People with mental health problems were nearly three times more likely also to have an addiction disorder compared to those without a mental health problem.
*PD personality disorder Source: Kessler RC et al (2005)
This more recent Australian national survey of 8,841 individuals was aimed at identifying mental health problems and the related disability. Overall 5.1% of the population had a past year substance use disorder and comorbidity was most common for mood and anxiety disorders…
The COSMIC study in the UK surveyed people attending community mental health teams (CMHT) and drug and alcohol services. Of CMHT patients, 44% (95% CI 38.1-49.9) reported a past-year problem of drug use and/or harmful alcohol use; 75% (95% CI 68.2-80.2) of drug service and 85% of alcohol service patients (95% CI 74.2-931) had a past-year psychiatric disorder. There appeared to be little scope for referral between substance use and mental health services. Some of the high prevalence of mental health problems may have been due to current substance use.
Averaged across survey data from six countries 20% of those peoples with alcohol problems and 26% with alcohol dependence also had a lifetime history of any mood disorder; for anxiety disorders the averages wee 25% and 32%. For people with drug dependence 35% met lifetime criteria for a mood disorder and 45% for an anxiety. There were strong associations across the board for conduct disorder (children) and antisocial behaviour…
Surveys :: Does severity of addiction increase comorbidity?
In this analysis increasing problems of personality, as indicated by the number of personality disorders, is associated with more mental health problems…
Meta-analysis :: Are traumatic events associated with substance misuse?
Thege et al (2017) Relationship between interpersonal trauma exposure and addictive behaviors: a systematic review. BMC Psychiatry 17:164
This meta-analysis of non help-seekers found an overall association of 35.1% between trauma and substance use. The association was 39.7% for trauma exposure in childhood compared to 29.7% for adult exposure. In a small proportion of cases, 1.3%, trauma had a negative association, meaning it seemed to have a protective, rather than causative, effect. Findings are mixed but broadly support stronger associations where there is more frequent trauma. It can be expected that help-seekers, notably the military and emergency services personnel, will have higher rates of positive association. Also bear in mind the typically long time lag between trauma and substance use or other mental health problems. Over the years many mediating factors could have influenced the route into or away from substance use.
How good are comorbidity interventions?
Our opinion
From a treatment point of view it is useful to get a timeline on when problems arose. Commonly an early experience of mental health problems can trigger substance use and vice-versa: for example, personality disorders and anxiety disorders antedate substance use, whereas mood disorders more commonly post date substance use.
Meta-analysis :: Clinical outcomes from Dialectical Behaviour Therapy (DBT)
Stoffers-Winterling JM et al (2022) Psychotherapies for borderline personality disorder: a focused systematic review and meta-analysis. British Journal of Psychiatry 221: 538-552
Pharmacotherapy is not associated with convincing, sustainable effects on Borderline Personality Disorder (Emotionally Expressive Disorder) and treatment is focused on psychotherapy. Individual therapies are less effective than individual work with group work add ons such as skills training. The analysis did not compare different interventions with each other and so it is not clear if other interventions are as effective as DBT.
Project MATCH in the USA was a large trial of addiction treatments. Twelve Step Facilitation did significantly better than both CBT and Motivational Enhancement on continuous abstinence, which is an exacting outcome measure…
For those not continuously abstinent MATCH treatments still delivered excellent results: days abstinent at the end of treatment for TSF 87%, CBT 85%, MET 77% (TSF & CBT 12 sessions, MET 4 sessions).
The best results for practitioners come from taking a structured approach to 12-step programmes (see the TSF manual above) rather than simply encouraging attendance. There are no charges for attending 12-step meetings and so cost effectiveness tends to be favourable. 12-steps can be mixed with other treatments provided there is no conflict with the goal of abstinence.
Project MATCH was supported and funded by the National Institute on Alcohol Abuse and Alcoholism and has made their Twelve Step Facilitation (TSF) manual available to practitioners.
more about mental health…
