The components of the assessment process for adults with possible ADHD are:
- Referral criteria
- Mode of referral
- Pre-assessment screening
- ADHD assessment
- Identification of co-morbidities
- The diagnosis
- The post assessment discussion
These are taken from the NICE Guidelines (2008, 2013, 2016, 2018) and Quality Standards (2013) and have been modified to meet Irish mental health service structures as mandated by AVFC (2006).
- Adults, including those with mild intellectual disability, with symptoms suggestive of ADHD associated with impairment of at least moderate severity who do not have a prior diagnosis of childhood ADHD.
- Adults who were diagnosed and treated for ADHD as children or adolescents and present with current symptoms of ADHD of at least moderate severity.
- Young people at age 18 with ADHD receiving treatment and care from CAMHS or paediatrics who continue to have significant symptoms of ADHD or other co-existing mental health conditions who require treatment.
Mode of Referral
Referrals for criteria 1 and 2 should be made by the person’s General Practitioner to the relevant local adult mental health service (General Adult or Psychiatry of Old Age).
Young people transitioning from CAMHS or paediatric services should be referred by their child psychiatrist or paediatrician for joint consideration by AMHT and the ADHD Clinic as outlined in Section 6.4; one of which, following consideration of the clinical information, takes the lead.
Initial Adult Mental Health Team (AMHT) assessment
The primary purpose of referral to AMHTs is to identify and treat any significant mental illness. This is recommended because of the high rate of co-morbidity of ADHD with mental illnesses. There is also the possibility of the symptoms of a mental illness mimicking those of ADHD.
In addition, referrals for possible ADHD should be asked to complete two self-rating scales. Likewise any other newly referred patient the clinician feels may have symptoms of ADHD should complete these scales. Two scales are recommended to minimise the risk of false positives.
- The Adult Self Report Scale (ASRS: Kessler 2005) Parts A and B to identify current ADHD symptoms. The ASRS is an official instrument of the World Health Organisation and has been used in large scale epidemiological studies to identify possible ADHD. For the purposes of screening the 6 questions in Part A are most predictive of the disorder. A score of 4/6 often/very often replies indicates further investigation for ADHD is warranted. The ASRS has a sensitivity of 68.7% and a specificity of 99.5% (Kessler 2005).
- The Wender Utah Rating Scale (WURS : Ward 1993) is a retrospective self-report instrument for adults consisting of 25 questions. Each item is rated 0 (not at all) to 4 (very much). It focuses on childhood ADHD. A total score of 36 indicates possible ADHD. The WURS has a high level of sensitivity and hence it is usefully combined with the ASRS.
Those screening positive on both scales, indicating both significant current and past ADHD symptoms, will then be seen at the ADHD clinic.
It should be explained to people in advance of undergoing screening that a positive result on both scales is required to proceed to formal assessment.
ADHD is diagnosed clinically in adults with evidence of typical symptoms. In making the diagnosis the three questions to be answered are:
- Did the symptoms begin during childhood and have they persisted throughout life?
- Can these symptoms not be better explained by another psychiatric diagnosis?
- Are they associated with moderate or severe psychological, social, educational or occupational impairments?
ADHD is a clinical and behavioural phenotype so requires evaluation through a diagnostic interview of the patient with supportive evidence from informants (Asherson 2005). Other supportive evidence such as school reports is especially helpful. The diagnosis should be made by a psychiatrist with the requisite training in the diagnosis and management of ADHD. The assessment process is the usual psychiatric assessment consisting of current complaints, full psychiatric history with special attention to both the developmental and psychiatric history and examination of the mental state. Information from relevant others (the collateral history) is an essential component of the assessment and may be obtained by another member of the team trained in the assessment and treatment of ADHD. As the assessment process by necessity must include careful and time consuming enquiry into the presence and absence of certain symptoms, this joint approach would increase efficiency. NICE (2008) summarises the components of assessment as:
- A full clinical and psychosocial assessment of the person; this should include discussion about behaviour and symptoms in the different domains and settings of the person’s everyday life.
- A full developmental and psychiatric history
- Assessment of the person’s mental state
- Observer reports.
Diagnosis should be made using DSM-5 criteria (APA 2013). DSM-5 defines ADHD as a persistent pattern of inattention and/or hyperactivity that interferes with functioning or development. The criteria for diagnosis are shown in Box 1 below.
Figure 1: DSM 5 criteria – Adult ADHD
Figure 2: DSM 5: ADHD symptoms – Inattention
Figure 3: DSM 5: ADHD symptoms – Hyperactivity
DSM-5 identifies four possible presentations:
- Combined (inattention and hyperactive/impulsive)
- Predominantly inattentive
- Predominantly hyperactive/compulsive
- ADHD in “partial remission”.
The domains of impairments include:
- Social relationships
- Coping with everyday activities
As part of the assessment, impaired functional domains should be sought. Impairment in at least two should be identified to confirm the diagnosis. Identification of these impairments also helps goal setting, an important part of treatment. The NICE Guidelines 2008 define impairment as:
- The degree to which most people would consider they require some form of medical, social or educational/occupational intervention.
- That without intervention there is likely to be long term adverse implications for the person.
- Impairment should be pervasive i.e. occurs in multiple settings and be of at least moderate severity.
Associated features that support the DSM-5 diagnosis of adult ADHD are:
- Development traits: mild delays in language, motor or social development are not specific to ADHD but often co-occur
- Emotional symptoms: low frustration tolerance, irritability, mood lability
- Educational problems: even in the absence of a specific learning difficulty, academic or work performance is impaired
- Cognitive deficits: may exhibit cognitive problems on tests of attention, executive function and memory - although tests are not sufficiently sensitive or specific to serve as diagnostic indices.
Given the detailed nature of the assessment together with the need to guide individuals to ensure all relevant symptoms are explored, this Clinical Programme recommends the use of the Diagnostic Interview for Adult ADHD (Kooij 2019). This can be downloaded from www.divacentre.eu. Whilst DIVA-2 (based on DSM 4R criteria) was available to download free of charge, a small once-off payment is now required by the DIVA foundation. This is because the American Psychiatric Association has increased its licence fee for the use of DSM-5 criteria 10 fold.
Identification of Co-morbidities
Diagnosis is complicated by the frequent occurrence of comorbidity. An essential part of the ADHD assessment is the identification of any co-morbid disorders. This requires the clinician to determine whether the mental health problems are a component of the ADHD or a separate comorbidity. If the former, the treatment is for ADHD; if the latter, the nature and severity of the comorbidity will determine which is treated first.
The co-morbidities associated with ADHD in adults include:
- Mood symptoms:
- emotional lability
- low self esteem
- depressive episode
- Substance use disorder
- Eating disorders
- Personality disorder (emotionally unstable / borderline)
- Autism spectrum disorder
- Sleep disorders
Appendix 3 is a useful checklist compiled by the UK Adult ADHD Network (UKAAN) to assist in differentiating between ADHD associated symptoms and separate co-morbid mental disorders.
For adults with possible ADHD, the differential diagnoses to be considered include mainly non-psychotic mental disorders. These are:
- Borderline/emotionally unstable personality disorder
- Substance misuse disorder
Whilst developmental disorders are important in children, they are less relevant in adults but nevertheless may need to be considered. These include specific learning disabilities, dyspraxia and autism spectrum disorder.
In considering both the diagnosis and subsequent treatment plan, it is recommended that a formulation addressing pre-disposing, maintaining and protective factors is drawn up. It is useful in determining the individual treatment plan enabling targeting of relevant issues in consultation with the individual.
Post assessment discussion
The person usually attends for assessment because he/she is hoping ADHD is the cause of certain troublesome symptoms or problems. If the diagnosis is not ADHD, it is important to provide information on what the cause, if identified, is and discuss management options.
Where the diagnosis is confirmed as ADHD, there is often a period of relief at having an explanation for why life has been so difficult. This may be followed by feelings of anger at having the diagnosis or that it was not identified sooner (Hansson Hallerod 2015). Post diagnosis counselling is, therefore, an important component of the treatment plan and should be offered early. It should cover three aspects:
- Psychoeducation about ADHD in adults. This should include a review of the symptoms indicative of the diagnosis and how it is a continuation from childhood symptoms.
- The patient’s reaction to the diagnosis focusing on the need to re-evaluate past perceived failures, the need to adjust to the diagnosis and it being seen as a positive development bringing the significant possibility of achieving goals in the future (contingent on a commitment to engagement with treatment).
- Education on the treatment options based on a multimodal approach. It should be explained that medication is still considered the first line of treatment in conjunction with non-pharmacological approaches to teach the individual adaptive strategies as part of the overall treatment plan.
Patients currently attending AMHTS
There is evidence that significant numbers of current attendees may have unrecognised ADHD (Roa 2011, Deberdt 2015). To assist in identifying people with possible ADHD, it will be a key part of the role of the ADHD Clinic professional staff to organise training in adult ADHD for all members of AMHTs.
Where it is considered that a current attendee may have ADHD and is mentally stable, the two screening scales should be administered. If both are positive, the person should be offered referral to the ADHD Clinic in the usual way.