Taxonomy and utility in the diagnostic classification of mental disorders

Maladaptive daydreaming should be included as a dissociative disorder in psychiatric manuals: position paper

Maladaptive daydreaming is a distinct syndrome in which the main symptom is excessive vivid fantasising that causes clinically significant distress and functional impairment in academic, vocational and social domains. Unlike normal daydreaming, maladaptive daydreaming is persistent, compulsive and detrimental to one's life. It involves detachment from reality in favour of intense emotional engagement with alternative realities and often includes specific features such as psychomotor stereotypies (e.g. pacing in circles, jumping or shaking one's hands), mouthing dialogues, facial gestures or enacting fantasy events. Comorbidity is common, but existing disorders do not account for the phenomenology of the symptoms. Whereas non-specific therapy is ineffective, targeted treatment seems promising. Thus, we propose that maladaptive daydreaming be considered a formal syndrome in psychiatric taxonomies, positioned within the dissociative disorders category. Maladaptive daydreaming satisfactorily meets criteria for conceptualisation as a psychiatric syndrome, including reliable discrimination from other disorders and solid interrater agreement. It involves significant dissociative aspects, such as disconnection from perception, behaviour and sense of self, and has some commonalities with but is not subsumed under existing dissociative disorders. Formal recognition of maladaptive daydreaming as a dissociative disorder will encourage awareness of a growing problem and spur theoretical, research and clinical developments.

How pharmacology can aid in the diagnosis of mental disorders

The precise diagnosis of mental disorders constitutes a formidable problem. Mental disorders are currently diagnosed based on clinical symptoms, which are often subjective. Various drug classes, traditionally referred to as "antidepressants," "antipsychotics" and "mood stabilizers" are then used empirically to treat affected patients. The previous decade has witnessed an increasing extension of the use of drug classes beyond their traditional indications (e.g., "antidepressants" in the treatment of anxiety disorders). Therefore, we would like to initiate a discussion in the pharmacological and psychiatric research communities on an alternative classification of mental disorders: Instead of using the traditional categorical classification of mental disorders physicians should rather diagnose symptoms (e.g., anhedonia) without bias to a traditional categorization (e.g., depression). The appropriate most effective drugs are then selected based on these symptoms. Depending on the responsiveness of the patient towards a given drug X, the disease should be classified, e.g., as drug X-responsive disease. This approach will also help us elucidate the still poorly understood molecular mechanisms underlying mental disorders, i.e., drugs can also be viewed and used as molecular diagnostic tools. In several fields of medicine, drugs are already used as molecular diagnostic tools. Thus, there is already precedence for the concept proposed here for mental disorders.

Conditional cash transfers and mortality in people hospitalised with psychiatric disorders: A cohort study of the Brazilian Bolsa Família Programme

BACKGROUND

Psychiatric patients experience lower life expectancy compared to the general population. Conditional cash transfer programmes (CCTPs) have shown promise in reducing mortality rates, but their impact on psychiatric patients has been unclear. This study tests the association between being a Brazilian Bolsa Família Programme (BFP) recipient and the risk of mortality among people previously hospitalised with any psychiatric disorders.

METHODS AND FINDINGS

This cohort study utilised Brazilian administrative datasets, linking social and health system data from the 100 Million Brazilian Cohort, a population-representative study. We followed individuals who applied for BFP following a single hospitalisation with a psychiatric disorder between 2008 and 2015. The outcome was mortality and specific causes, defined according to International Classification of Diseases 10th Revision (ICD-10). Cox proportional hazards models estimated the hazard ratio (HR) for overall mortality and competing risks models estimated the HR for specific causes of death, both associated with being a BFP recipient, adjusted for confounders, and weighted with a propensity score. We included 69,901 psychiatric patients aged between 10 and 120, with the majority being male (60.5%), and 26,556 (37.99%) received BFP following hospitalisation. BFP was associated with reduced overall mortality (HR 0.93, 95% CI 0.87,0.98, p 0.018) and mortality due to natural causes (HR 0.89, 95% CI 0.83, 0.96, p < 0.001). Reduction in suicide (HR 0.90, 95% CI 0.68, 1.21, p = 0.514) was observed, although it was not statistically significant. The BFP's effects on overall mortality were more pronounced in females and younger individuals. In addition, 4% of deaths could have been prevented if BFP had been present (population attributable risk (PAF) = 4%, 95% CI 0.06, 7.10).

CONCLUSIONS

BFP appears to reduce mortality rates among psychiatric patients. While not designed to address elevated mortality risk in this population, this study highlights the potential for poverty alleviation programmes to mitigate mortality rates in one of the highest-risk population subgroups.

The assessment of transdiagnostic dimensions of emotional disorders: Validation of the Multidimensional Emotional Disorders Inventory (MEDI) in adolescents with subthreshold anxiety and depression

BACKGROUND

The transdiagnostic approach to psychopathology has emerged as an alternative to traditional taxonomic approaches. The Multidimensional Emotional Disorders Inventory (MEDI) is a specifically designed self-report to measure the transdiagnostic dimensions proposed by Brown and Barlow (2009). This study aims to analyse the psychometric properties of the MEDI scores in adolescents with subthreshold anxiety and depression.

METHOD

The sample consisted of a total of 476 students. The mean age was 13.77 years (SD = 1.43) (range 10 to 18 years), 73.9 % were females. Several questionnaires assessing positive affect, negative affect, mental health difficulties, and quality of life were used.

RESULTS

The original 9-factor structure of the MEDI was confirmed with good fit indices. Satisfactory levels of internal consistency were observed in most of the MEDI scores using McDonald's Omega, ranging from 0.58 to 0.87. The MEDI dimensions were associated with psychopathology, positive affect, negative affect, and quality of life.

LIMITATIONS

Reliance on self-reported data, a cross-sectional design limiting temporal assessment, and a 73.9 % female gender imbalance.

CONCLUSION

The MEDI scores showed adequate psychometric properties among adolescents with subclinical emotional symptoms. The results found might have potential clinical implications for conceptualization, assessment, intervention, and prevention of emotional disorders at both clinical and research levels.

The harmonium model and its unified system view of psychopathology: a validation study by means of a convolutional neural network

The harmonium model (HM) is a recent conceptualization of the unifying view of psychopathology, namely the idea of a general mechanism underpinning all mental disorders (the p factor). According to HM, psychopathology consists of a low dimensional Phase Space of Meaning (PSM), where each dimension of meaning maps a component of the environmental variability. Accordingly, the lower thenumber of independent dimensions in the PSM, and hence its intrinsic complexity, the more limited the way of interpreting the environment. The current simulation study, based on a Convolutional Neural Network (CNN) framework, aims at validating the HM low-dimensionality hypothesis. CNN-based classifiers were employed to simulate normotypical and pathological cognitive processes. Results revealed that normotypical and pathological CNNs were different in terms of both classification performance and layer activation patterns. Using Principal Component Analysis to characterize the PSM associated with the two algorithms, we found that the performance of the normotypical CNN relies on a larger and more evenly distributed number of components, compared with the pathological one. This finding might be indicative of the fact that psychopathology can be modelled as a low-dimensional, poorly modulable PSM, which means the environment is detected through few components of meaning, preventing complex information patterns from being taken into account.