ADHD - overlap in diagnostic vulnerability and impact of treatment

Two papers in the Journal this month address the extent to which aetiological vulnerability for attention-deficit hyperactivity disorder (ADHD) is shared with other severe mental illnesses. Larsson et al (pp. 103-106) examine risk of bipolar disorder and schizophrenia among relatives of ADHD probands using data from the Swedish longitudinal national registers. They found evidence of increased risks of both disorders among relatives of the proband group, with risks among half-siblings lower than in full siblings and similar risks present in maternal and paternal half-siblings. The authors conclude that this pattern of shared vulnerability supports the sharing of genetic rather than environmental risk factors. Hamshere et al (pp. 107-111) took Psychiatric Genome-wide Association Study Consortium adult schizophrenia data to identify alleles overrepresented among those with schizophrenia, and tested the frequency of risk allele occurrence in a sample of children with ADHD compared with controls; the approach was repeated for bipolar disorder risk alleles. The authors found that the schizophrenia risk alleles differentiated children with ADHD from controls, with stronger discrimination evident for those alleles associated with risk of both schizophrenia and bipolar disorder.

Both studies appear to support the need for aetiological research to extend across traditional diagnostic boundaries. In a linked editorial, Faraone (pp. 81-83) also highlights the importance of such research for clinicians addressing the complexities of comorbidity when developing formulations and treatment approaches, and points to the accumulating support for considering psychopathology in dimensional rather than categorical terms.

A third ADHD-focused paper in the Journal this month examines the impact of stimulant treatment on risk of substance use disorder and nicotine dependence (Groenman et al, pp. 112-119). After a mean follow-up period of 4.4 years, those individuals with ADHD who had received stimulant treatment were found to be at reduced risk of developing a substance use disorder compared with those not receiving treatment and were at similar risk when compared with a healthy control group. The occurrence of nicotine dependence was not affected by stimulant treatment; all those in the ADHD group had a risk elevated above that of the healthy control group.

Public attitudes towards mental illness and internalised stigma

On the basis that approaches to treatment and aetiological understanding of mental illness has changed significantly over past decades, Angermeyer et al (pp. 146-151) examined changing public attitudes to mental illness in Germany utilising data from population surveys conducted in 1990 and 2011. Although members of the public were more likely in the recent survey to endorse a biological causation of schizophrenia, they were less likely to do so when asked to consider depression and alcohol dependence. Attitudes towards help-seeking and treatment appeared to have improved while attitudes to those with mental illnesses such as schizophrenia worsened.

One aspect of the caution surrounding treatment of individuals identified as having an at-risk mental state for psychosis has been the concern that even psychological interventions might unintentionally produce harms such as an increase in internalised stigma. In a multisite randomised controlled trial of cognitive therapy for prevention and amelioration of psychosis in a sample meeting criteria for at-risk mental state, Morrison et al (pp. 140-145) found that negative appraisals of experiences were actually reduced in the treated sample while there was no significant impact on appraisals of the social acceptability of experiences.

In a novel editorial published in the Journal this month, Burns & Rose (pp. 88-89) describe a difficult exchange following a presentation about coercive treatment at a mental health conference, one author providing the perspective of a professional and the other a service user. The two authors reflect both on how to improve clinical practice in this area and on the dialogue itself.

Collaborative care for common mental disorders

In a cluster randomised controlled trial of collaborative stepped care for common mental disorders (care guided by a psychiatric nurse in primary care with addition of antidepressants for severe disorder and followed by cognitive-behavioural therapy in mental healthcare), Oosterbaan et al (pp. 132-139) found that those in the treatment group showed earlier evidence of response to treatment but by 8 months post-test and 12 months follow-up no significant differences were apparent between the treatment and care as usual groups. The collaborative stepped care approach was favoured by patients.

In a linked editorial, Roy-Byrne (pp. 86-87) comments on the difficulties of implementing a collaborative care model for common mental disorders in primary care, at least in the USA, despite the extent of evidence supporting such an approach. The novel elements of the study by Oosterbaan and colleagues are also highlighted in this editorial, particularly the importance of nesting such research in large health systems where cluster randomisation by clinic is possible and where the approach can be applied beyond depression to other common mental disorders. The issue is discussed in the context of impending changes to the way healthcare is provided in the USA.