Diagnostiquer et traiter le TDAH et le trouble bipolaire comorbide chez l’adulte

Abstract

Objectives

Attention deficit with or without hyperactivity disorder (ADHD) and bipolar disorder (BD) are two frequent adult psychiatric conditions with high rates of comorbidity. The existence of a symptom overlaps and the lack of knowledge of physicians concerning this double diagnosis can lead to underdiagnosis or to overdiagnosis of this comorbidity, which has a therapeutic and prognostic impact. The aim of this paper is to provide the information on how to screen, diagnose, and manage this comorbidity to the French-speaking practitioners.

Methods

We conducted a narrative review of literature to gather the updated information on how to differentiate between ADHD and BD, the specificities of the comorbidity, the existing screening and diagnostic tools, and the treatment approaches.

Results

During the clinical interview the practitioner needs to gather information regarding the age of symptoms onset, their evolution, and analyze in detail the signs and symptoms presented. Symptoms of ADHD are often present before 7 years old which is an age where BD is rare, and BD has a cyclical evolution, as opposed to ADHD which is a chronic condition. The symptomatic dimensions that overlap between ADHD and BD can be distinguished by an in-depth analysis. Depressive episodes, periods of libido increase and/or a reduced need for sleep, psychotic symptoms, and suicidal risk are in favor of BD and they are never present in ADHD. Regarding the comorbidity of ADHD and BD, many studies are in favor of a distinct entity with a separate clinical phenotype. This clinical phenotype is often marked by the early onset of mood episodes, a high frequency of mood episodes with mixed features, a BD that is partially resistant to pharmacological treatment, a history of violent behavior and suicide attempts, the presence of certain additional comorbidities, difficulties in socio-professional settings or a history of school difficulties. These characteristics can be considered as “red flags” that the practitioner should look out for. To correctly diagnose ADHD and BD comorbidity in adults, the practitioner must do a clinical assessment where he can use psychometric tools to support his clinical observation. The screening tools that can be used for BD are the Mood Disorder Questionnaire (MDQ) and the Hypomania CheckList (HCL-32). For ADHD there is the Adult ADHD Self-Report Scale (ASRS) and the Wender Utah Rating Scale (WURS). The use of a structured clinical interview such as the Mini International Neuropsychiatric Interview (MINI) or the Diagnostic Interview for ADHD in Adults (DIVA-5) can help to diagnose the conditions. Most of these tools are validated in French. The interest of neuropsychological testing in the screening and diagnosis of this comorbidity is limited, but it can be helpful in establishing a cognitive remediation treatment plan. The treatment of ADHD and BD comorbidity includes pharmacological and non-pharmacological approaches. The pharmacological treatment must be done in a stepwise and hierarchical way. Mood stabilization is generally the first step before treatment of ADHD. Once euthymia is achieved, the second step is to re-evaluate the presence of ADHD symptoms and their functional impairment. If ADHD symptoms present a functional impairment, then the third step is to treat them, by combining the mood stabilizer with the pharmacological treatment of ADHD. About mood stabilizing treatments, it is recommended to prioritize less sedative and non-antipsychotic drugs, such as lithium, sodium valproate and lamotrigine. Atypical antipsychotics can be used to achieve mood stabilization but should be used with precaution when used in combination with a psychostimulant treatment due to the risk of stimulant-antipsychotic syndrome. Regarding the treatment of ADHD, the only treatment with French marketing-authorization in adult population is methylphenidate. The prescription of atomoxetine and amphetamines is possible by request for Compassionate Access Authorization. In patients with the comorbidity of ADHD and BD, according to the different international guidelines and considering the French regulation, it seems that for French practitioners, the treatment of ADHD should prioritize a long-acting methylphenidate in combination with a mood stabilizer with anti-manic properties. As a second-line option the use of atomoxetine should be considered, as a third-line option bupropion, and as a fourth-line option modafinil or lisdexamphetamine. Regarding the non-pharmacological treatment of the comorbidity of ADHD and BD, measures such as psychoeducation, cognitive-behavioral therapy, mindfulness-based therapies, cognitive remediation, and psychosocial rehabilitation, can be proposed. Neuromodulation therapies also seem to be effective in patients with the comorbidity.

Conclusion

The knowledge of in-depth clinical aspects of both BD and ADHD, as well as the specific clinical characteristics of the comorbidity, facilitates the differential diagnosis and alerts the practitioner to the presence of the comorbidity. The use of psychometric tools can be of aid to the clinician in the diagnostic process. More studies are still needed regarding the treatment of the comorbidity of ADHD and BD in adult patients.