Research Roundup February 2024: Recently Published Findings From AFSP-Funded Studies

The Research Roundup is a regular update of recently published findings in suicide prevention research. AFSP-funded studies included in this roundup examined how…

• Pharmacological and somatic treatments work for adults at risk for suicide
• Some characteristics in school-aged children contribute to suicidal thoughts and behaviors
• Different types of firearms, and the policies around them, may affect suicide rates, and
• Genetic molecules may indicate risk for mood disorders and suicide

Researcher: Samuel Wilkinson, MD
Institution: Yale University
Grant Type: 2018 Young Investigator Grant – $84,706
Grant Title: Effect of Electroconvulsive Therapy on Suicide Attempts in Geriatrics Patients with Depression

When working with a person at risk for suicide, clinicians have a wide variety of treatments at their disposal. Their selection of treatment is typically dependent upon the clinical context of the person at risk — their diagnosis and known risk factors — and the research-based evidence of each treatment’s effectiveness in clinical practice. In suicide prevention, two types of treatments available to clinicians that are often used are psychopharmacological interventions (medications for mental health conditions) and somatic (relating to the body) interventions, such as electroconvulsive therapy (ECT) and transcranial magnetic stimulation (TMS).

To assess the efficacy of psychopharmacological and somatic interventions on suicide risk, Dr. Samuel Wilkinson conducted a meta-analysis and systematic review of the previous research on these two types of treatments (excluding antidepressants). After searching and selecting from nearly 3,000 publications, Dr. Wilkinson found that lithium (for bipolar disorder) and clozapine (for psychotic disorders) were associated with a reduction in the odds of suicide. Regarding somatic treatments, ECT was not found to be significantly associated with a reduction in the odds of suicide. Other somatic treatments, such as vagus nerve stimulation and TMS among others, did not have enough studies to analyze an association — signaling a need for more research on existing and novel interventions for suicide prevention.

Citation: Wilkinson, S. T., Trujillo Diaz, D., Rupp, Z. W., Kidambi, A., Ramirez, K. L., Flores, J. M., Avila-Quintero, V. J., Rhee, T. G., Olfson, M., & Bloch, M. H. (2022). Pharmacological and somatic treatment effects on suicide in adults: A systematic review and meta-analysis. Depression and Anxiety, 39(2), 100-112, http://dx.doi.org/10.1002/da.23222    

Researcher: Arielle Sheftall, PhD
Institution: The Abigail Wexner Research Institute at Nationwide Children's Hospital
Grant Type: 2020 Young Investigator Grant – $90,000
Grant Title: Suicidal Behavior in Elementary School-Aged Youth: Assessment of Familial Factors and Neurocognitive Functioning

Though infrequent when compared to other age groups, suicidal thoughts and behaviors (STBs) have increased in elementary school-aged children in recent years. Despite prior research indicating that feelings of hopelessness, mood disorder symptoms, and a familial history of suicidal behaviors may be associated with STBs in preteens, little is known in terms of established risk factors (or contributors to risk). More research has been needed to improve screening, assessment, and prevention efforts for this age group.

To help determine risk factors for STBs in preteens, Dr. Arielle Sheftall examined the neurocognitive (skills linked to specific parts of the brain) and clinical characteristics of 93 elementary school-aged children with and without a history of STBs. After administering a series of clinical interviews and neurocognitive tests, Dr. Sheftall found that children who reported a history of suicidal thoughts and behaviors were typically older, had higher levels of depressive and anxiety symptoms, and were more likely to have a parent with a history of STBs. Poorer performance in neurocognitive skills, such as attentional flexibility and inhibitory control were also significantly associated with STBs. These results provide targets for future suicide prevention efforts in elementary-aged children and offer the opportunity for upstream interventions before STBs develop.

Citation: Chen, Q., Armstrong, S. E., Vakil, F., Bridge, J. A., Keilp, J. G., & Sheftall, A. H. (2023). Neurocognitive and clinical characteristics of elementary school-aged children with a history of suicidal thoughts and behaviors. Journal of Affective Disorders, 339, 318–324. https://doi.org/10.1016/j.jad.2023.07.038    

Researcher: Paul Nestadt, MD
Institution: Johns Hopkins Bloomberg School of Public Health
Grant Type: 2019 Young Investigator Grant – $90,000
Grant Title: Characterizing Suicides among Opioid-Related Deaths

More than 50% of suicide deaths involve a firearm. One method of attempting to decrease the number of suicides is through limiting access to firearms with state-level policy. In 2013, the state of Maryland passed the Firearms Safety Act (FSA) which limited the private sale of handguns (via age restriction, permits, and training), but did not limit the sale of long guns (e.g., rifles and shotguns) often used for hunting. There has been a question as to whether the omission of long guns in the FSA played a part in suicide rates following its implementation.

To examine the effectiveness of the Firearms Safety Act, Dr. Paul Nestadt assessed the frequency of adult suicides caused by firearms before and after its passing in 2013. Following the analysis of information about 4,107 people who died by suicide with a firearm between 2003 and 2019, Dr. Nestadt found that handgun suicides significantly decreased in the period after 2013’s Firearms Safety Act. However, long gun suicides did not decrease, and actually increased during the wintertime hunting season. These findings highlight the potential for state policy to affect change in the frequency of firearms suicide deaths, as well as the importance of ensuring that these policies are comprehensive.

Citation: Pan, I., Zinko, J., Weedn, V., & Nestadt, P. S. (2023). Long gun suicides in the state of Maryland following the firearm safety act of 2013. Suicide and Life-Threatening Behavior, 53(1), 29-38, http://dx.doi.org/10.1111/sltb.12919   

Researcher: Yogesh Dwivedi, PhD
Institution: University of Alabama at Birmingham  
Grant Type: 2019 Distinguished Investigator Grant – $125,000
Grant Title: MicroRNA Mediators of Early-Life Stress Vulnerability in Suicidal Behavior

Mood disorders, such as major depressive disorder (MDD) and bipolar disorder (BD), are the most prevalent psychiatric conditions associated with an increased risk of suicide, but there are still questions around the underlying mechanisms. Genetic factors influence the way the brain functions and are thought to play a role in suicide risk through changes in the expression of particular microRNA (miRNAs), which are segments of genes that respond in real time to the environment. A recent aim in the field of genetic research involves unraveling the connection between miRNAs, mood disorders, and suicide. Understanding miRNAs may hold significant implications for the development of innovative treatments and strategies for preventing suicide.

With this in mind, Dr. Yogesh Dwivedi reviewed and synthesized previous studies that have contributed significant findings to our understanding of the role of miRNAs as potential biomarkers (biological indicators) for MDD, BD, and suicide risk. While acknowledging the potential of miRNAs to help predict and prevent suicide, Dr. Dwivedi identified challenges in using them in neuropsychiatry. Genetic differences in individuals related to medications, nutrition, and exposure to environmental conditions make it difficult to fully describe a population-wide role for specific miRNAs. He also noted that a promising method of study called Cerebrospinal Fluid-based Analysis may be too invasive and not practical large-scale use. Based on his review, Dr. Dwivedi recommended meticulous, long-term studies to validate findings.

Citation: Roy, B., Ochi, S., Dwivedi, Y. (2023) Potential of Circulating miRNAs as Molecular Markers in Mood Disorders and Associated Suicidal Behavior. International Journal of Molecular Sciences. 24, 4664. https://doi.org/10.3390/ijms24054664

Learn more about the AFSP research grants featured in this monthly roundup, as well as others, here.