Diagnosis, identification and risk populations

Diagnosis: Opioid Dependence

There are two principle diagnostic classification systems:

ICD-11 (International Classification of Disease – eleventh revision produced by the World Health Organisation)
DSM-V-TR (Diagnostic Statistical Manual – fifth edition, text revision produced by the American Psychiatric Association).

There are similarities between the two but for the purposes of this document we have used ICD-11, which defines opioid dependence (code 6C43) as:

A disorder of regulation of opioid use arising from repeated or continuous use of opioids. The characteristic feature is a strong internal drive to use opioids, which is manifested by impaired ability to control use, increasing priority given to use over other activities and persistence of use despite harm or negative consequences. These experiences are often accompanied by a subjective sensation of urge or craving to use opioids. Physiological features of dependence may also be present, including tolerance to the effects of opioids, withdrawal symptoms following cessation or reduction in use of opioids, or repeated use of opioids or pharmacologically similar substances to prevent or alleviate withdrawal symptoms. The features of dependence are usually evident over a period of at least 12 months, but the diagnosis may be made if opioid use is continuous (daily or almost daily) for at least 3 months.

ICD-11 states that a pattern of recurrent episodic or continuous use of opioids with evidence of impaired regulation of opioid use is manifested by two or more of the following:

Impaired control over opioid use (i.e., onset, frequency, intensity, duration, termination, context).
Increasing precedence of opioid use over other aspects of life, including maintenance of health, and daily activities and responsibilities, such that opioid use continues or escalates despite the occurrence of harm or negative consequences (e.g., repeated relationship disruption, occupational or scholastic consequences, negative impact on health).
Physiological features indicative of neuroadaptation to the substance, including:

1) tolerance to the effects of opioids or a need to use increasing amounts of opioids to achieve the same effect.

2) withdrawal symptoms following cessation or reduction in use of opioids (see Opioid Withdrawal), or

3) repeated use of opioids or pharmacologically similar substances to prevent or alleviate withdrawal symptoms.

The features of dependence are usually evident over a period of at least 12 months, but the diagnosis may be made if use is continuous (daily or almost daily) for at least 3 months.

ICD-11 goes on to state additional clinical features that may accompany the above essential features of opioid dependence:

A subjective sensation of urge or craving to use opioids often, but not always, accompanies the essential features of opioid dependence.
When present as an aspect of opioid dependence, withdrawal symptoms must be consistent with the known withdrawal state for opioids.
Tolerance varies as a function of individual factors (e.g., substance use history, genetics) and should be differentiated from initial levels of response during intoxication, which also exhibit significant individual variability. Laboratory testing that reveals high levels of the substance in bodily fluids with no evidence of significant symptoms of intoxication may be suggestive of tolerance. Tolerance to the effects to substances as indicated by different psychophysiological responses can develop at varying rates (e.g., tolerance to respiratory depression caused by opioid intoxication may develop prior to tolerance to the sedating effects of the drug). With abstinence, tolerance effects diminish over time.
Individuals with certain co-morbid medical conditions (e.g., chronic liver disease) typically have reduced tolerances to substances.
Physical or mental health consequences (beyond the essential features of substance dependence) typically occur in persons with substance dependence but are not required for the diagnosis. Similarly, functional impairment in one or several domains of life (e.g., work, domestic responsibilities, child-rearing) is commonly seen in persons with substance dependence, but is not required in order to assign the diagnosis.
Individuals with substance dependence have elevated rates of many other mental disorders, including conduct-dissocial disorder, attention deficit hyperactivity disorder, impulse control disorders, post-traumatic stress disorder, social anxiety disorder, generalised anxiety disorder, mood disorders, psychotic disorders, and personality disorder with prominent dissocial features, as well as subthreshold symptoms. The specific pattern of co-occurrence depends on the specific substance involved, and reflects common risk factors and common causal pathways. These are distinguished from substance-induced mental disorders, in which the symptoms are a result of the direct physiological effects of the substance on the central nervous system.
A pattern of substance use that includes frequent or high dose administration occurs more often among certain subgroups (e.g., adolescents). In these cases, peer group dynamics may contribute to the maintenance of substance use. Regardless of the social contributions to the behaviour, a pattern of substance use that is consistent with subgroup norms should not be considered as presumptive evidence of substance dependence unless all diagnostic requirements for the disorder are met.

Indicators

Indicators that suggest the possibility of dependence should be explored in those on a long-term opioid prescription:

Long-term prescribing of opioids for non-cancer conditions.
Current or past psychiatric illness or profound emotional trauma.
Reports of concern by family members or carers about opioid use.
Concerns expressed by a pharmacist or other healthcare professionals about long-term opioid use.
Insistence that only opioid treatment will alleviate pain and refusal to explore other avenues of treatment.
Refusal to attend or failure to attend appointments to review opioid prescription.
Resisting referral for specialist addiction assessment.
The repeated seeking of prescriptions for opioids with no review by a clinician.
Repeatedly losing medications or prescriptions.
Taking doses larger than those prescribed or increasing dosage without consulting the clinician; often coupled with seeking early replacement prescriptions. Associated with continued requests for dose escalations.
Seeking opioids from different doctors and other prescribers. This can take place within GP practices, often identifying locum doctors or doctors unfamiliar with their case. This may be associated with attempting unscheduled visits.
Obtaining medication from multiple different providers, NHS and private GPs, repeatedly and rapidly deregistering and registering with GPs, seeking treatment for the same condition from both specialists and GP; or seeking treatment from multiple specialists. This may be coupled with a refusal to agree to writing to the main primary care provider.
Obtaining medications from the internet or from family members or friends.
Resisting referrals to acute specialists about complex physical conditions or failing to attend specialist appointments.
Appearing sedated in clinic appointments.
Misusing alcohol or using illicit or over-the counter, internet or other prescribed drugs or a past history of alcohol or other drug dependence.
Deteriorating social functioning including at work and at home.
Resisting or refusing drug screening.
Signs or symptoms of injecting opioids or snorting oral formulations.

Assessment

A comprehensive history should be taken from any patient in whom opioid dependence is suspected. It is important to understand the medical indication for which opioids were prescribed initially. As far as possible, confrontation should be avoided, as should judgement about the motivations of the patient. Important points that should be clarified include:

Medical indication for opioid.
Full list of all medication, routes of administration and how long prescribed.
What other medication with addictive potential is prescribed to the patient including benzodiazepines and gabapentin/pregabalin.
What the patient perceives as positive and negative attributes of prescribed opioids.
Current alcohol and illicit drug use.
Current physical health.
Current psychological health.
Current tobacco consumption.
Previous history of drug and alcohol dependence and treatment.
Physical health history and any interventions.
History of psychiatric illness.
Social functioning and employment status.
Family and carer support.
Appropriate physical examination.

Investigations

Urine or other drug screening for prescribed opioid and commonly abused illicit drugs.
Consider use of the Objective Opioid Withdrawal Scale (OOWS) and the Subjective Opioid Withdrawal Scale (SOWS) where relevant.
Relevant blood tests possibly including full blood count, liver function tests, hepatitis B & C, and HIV.
Any other relevant investigations regarding condition for which opioids were initially prescribed.

Other sources of information should be sought including:

Discuss with other clinicians currently (or previously where relevant) involved in patients care.
Clinic letters regarding prescription or underlying diagnosis.
Information from family or carers.

Risk Populations

Broadly speaking three groups are at increased risk of dependence on prescribed opioids. These groups are not mutually exclusive. They are:

Patients who find the mood-elevating effects of opioids beneficial but have underlying psychological distress or diagnosed psychiatric illness. Any patient on long-term opioids should be reviewed regarding their psychological health. This is especially true of those with a current or past history of psychiatric illness. In these cases, they warrant treatment for opioid dependence, but of equal importance is treatment of the underlying psychiatric condition.
Those without psychological distress who find themselves dependent but are very willing to engage in reduction programs and further addiction treatment.
Those with a history of alcohol or drug dependence who may or may not be willing to engage in further assessment or treatment.

NB: Long-term epidemiological data show that patients with co-morbid mental health diagnoses or a history of addiction are more likely to receive opioids for pain and are more likely to be prescribed high doses, multiple opioids and other psychoactive drugs (e.g., benzodiazepines). This phenomenon has been described as ‘adverse selection’.

Other resources in this section

Opioids & addiction

Opioids Aware homepage