Did the human genome project affect research on Schizophrenia?

Examining the Long-Term Impacts of Psychotropic Drugs and Considerations for People Discontinuing Treatment

Psychotropic drugs dominate the mental healthcare landscape. This is despite contention over their proposed mechanism of action, concerns for their adverse effects, and questionable effectiveness, especially over the long term. Mental health nurses are routinely involved in administering psychotropic drugs, observing for and managing adverse effects, and providing information and support to people prescribed these agents. This critique explores the current understanding of the mechanism of action for psychotropic drugs, evidence for their effectiveness, adverse effect burden and implications for long term use. The role of mental health nurses in deprescribing and supporting people to discontinue treatment is considered.

Low Stability and Specificity of Polygenic Risk Scores for Major Psychiatric Disorders Limit Their Clinical Utility

BACKGROUND

There has been little examination of the stability and validity of polygenic risk scores (PRSs), i.e., whether individuals identified as high risk for a disorder with one PRS are identified as high risk with another PRS and whether high-risk individuals have the disorder.

METHODS

The UK Biobank recruited 502,534 individuals ages 37 to 73 years in the United Kingdom between 2006 and 2010. PRSs were calculated for 408,853 White British individuals. PRS continuous shrinkage (CS), which uses single nucleotide polymorphism effect sizes under CS, was used to calculate 3 different PRSs for major depressive disorder (MDD), alcohol use disorder (AUD), and type 2 diabetes (T2D) and 2 different PRSs for schizophrenia (SCZ). PRS stability was measured using correlations between different PRSs for the same disorder and the percentage of individuals consistently identified as high risk (top 5% PRS). Sensitivity and specificity were used to measure PRS validity.

RESULTS

Correlations between PRSs ranged from low to high (SCZ: r = 0.78; MDD: rs = 0.16-0.78; AUD: rs = 0.13-0.90; T2D rs = 0.29-0.77). The percentage of individuals consistently identified as high risk (top 5% PRS) for SCZ with a different SCZ PRS was 47.7%, i.e., less than half of individuals identified as high risk with one PRS were identified as high risk with another PRS. Percentages of individuals consistently identified as high risk were 9.5% to 47.0% for MDD, 8.3% to 63.5% for AUD, and 14.1% to 45.2% for T2D. PRS sensitivity was moderate for MDD (66.1%-74.4%) and AUD (72.3%-74.2%), moderate/good for T2D (77.3%-96.3%), and good for SCZ (90.2%-93.3%). Specificity was low for all PRSs (50.7%-56.4%).

CONCLUSIONS

Limited stability and specificity of PRSs highlight their current lack of clinical utility in psychiatry.

The Relationship Between Breast and Gynecological Cancers and a Diagnosis of Serious Mental Illness: A Scoping Review

Women who are living with a diagnosis of serious mental illness face an elevated risk of premature mortality from breast and gynecological cancers. To understand the risk factors associated with prevalence and premature death from breast or gynecological cancer in women diagnosed with an SMI, a scoping review was conducted, using the Arksey and O'Malley framework in accordance with the PRISMAScR guidelines. Four electronic databases were searched for research from 2012 to 2024. The 21 selected articles identified potential factors associated with our target: clinical status, coordination of care across health services, and social and family support. The findings suggest that the keys to improving outcomes are conducting proper screening among women diagnosed with SMI, coordinating mental health and oncological care, and capitalizing on available family support.

Glial Derived Neurotrophic Factor and Schizophrenia Spectrum Disorders: A Scoping Review

BACKGROUND

Psychotic disorders, characterized by altered brain function, significantly impair reality perception. The neurodevelopmental hypothesis suggests these disorders originate from early brain development disruptions. Glial-derived neurotrophic factor (GDNF) is crucial for neuronal survival and differentiation, especially in dopaminergic neurons, and shows promise in neurodegenerative and neuropsychiatric conditions.

OBJECTIVES

This scoping review aims to examine the role of GDNF in schizophrenia spectrum disorders and substance-induced psychoses, integrating knowledge on the neurobiological mechanisms and therapeutic potential of GDNF.

METHODS

A comprehensive literature search was conducted using PubMed and Scopus databases from January 2001 onwards. Data extraction focused on GDNF levels, cognitive function, antipsychotic treatment effects, and genetic studies.

RESULTS

The review included 25 studies (18 human, 7 animal). While some studies demonstrated inconsistent results regarding GDNF serum levels in schizophrenic patients, the majority reported correlations between GDNF levels and cognitive functions. Animal studies underscored GDNF's role in stress response, drug-induced neurotoxicity, and dopamine signaling abnormalities. Genetic studies revealed potential associations between GDNF gene polymorphisms and schizophrenia susceptibility, though findings were mixed.

DISCUSSION

GDNF plays a significant role in cognitive functions and neuroprotection in schizophrenia. The variability in study results underscores the complexity of GDNF's involvement. The therapeutic potential of GDNF in psychotic disorders remains unclear, necessitating further research to clarify its efficacy and safety.

CONCLUSION

This review emphasizes the importance of integrated biomarker strategies, gene therapy approaches, and precision medicine in advancing the understanding and treatment of psychotic disorders.

Early detection and intervention through the lens of the neurodevelopmental framework: the salience of developmental years and related services

Broadening prediction efforts from imminent psychotic symptoms to neurodevelopmental vulnerabilities can enhance the accuracy of diagnosing severe mental disorders. Early interventions, especially during adolescence, are vital as these disorders often follow a long prodromal phase of neurodevelopmental disturbances. Child and adolescent mental health services should lead a developmentally-sensitive model for timely, effective detection and intervention.