29 Jul PET Scan Identifies Low Serotonin Functioning Linked To Suicidal Behavior
Posted at 22:04h
in Author Interviews, Depression, Medical Imaging, Mental Health Research, Radiology
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Dr. Maria Oquendo[/caption]
MedicalResearch.com Interview with:
Maria A. Oquendo, M.D.
Professor of Psychiatry
Vice Chair for Education
Columbia University Medical Center
American Psychiatric Association, President
International Academy of Suicide Research, President
MedicalResearch.com: What is the background for this study? What are the main findings?
Response: Our team has worked for years on identifying the biological underpinnings of both risk for suicidal behavior (SB) and for predicting the lethality or medical consequences of suicidal behavior. We have shown that if you compare those who are depressed and have had SB to those who are depressed but do not have suicidal behavior, you can see clear differences in the serotonin system using Positron Emission Tomography and a molecule tagged with radioactivity. We predicted that if you could see these differences cross-sectionally, then their presence might also predict suicidal behavior and its lethality in the future. Our study showed that those with higher serotonin 1a binding in the raphe nuclei, which likely indicates low serotonin functioning, made more medically damaging suicide attempts in the two years that followed. They also suffered from more pronounced suicidal ideation in the subsequent year.
Dr. Mima Becevic[/caption]
Mirna Becevic, PhD, MHA
Assistant Research Professor
University of Missouri - Department of Dermatology
Missouri Telehealth Network
MedicalResearch.com: What is the background for this study?
Response: Psychiatry is, by far, the biggest utilizer of telemedicine services on the Missouri Telehealth Network (MTN). MTN supports an average of 4000 tele-psychiatry appointments every month, and 10% of those are provided by the University of Missouri Department of Psychiatry. Since we are all aware of the ever-increasing demand for child and adolescent psychiatry, but also the stigma that goes along with it, we wanted to examine more closely the actual usage of those services at the University of Missouri.
Dr. Guang Yang[/caption]
Guang Yang, Ph.D.
Assistant Professor
NYU Langone School of Medicine
Alexandria Center for Life Sciences
New York, NY 10016
MedicalResearch.com: What is the background for this study? How common is the problem of long-lasting behavioral deficits after repeated anesthesia exposure in neonates?
Response: Each year, in the United States alone, more than 1 million children under 4 years of age undergo surgical procedures that require anesthesia. Many lines of evidence from animal studies have shown that prolonged or repeated exposure to general anesthesia during critical stages of brain development leads to long-lasting behavioral deficits later in life. The results from human studies are less clear, although some studies suggest a higher incidence of learning disabilities and attention-deficit and hyperactivity disorders in children repeatedly exposed to procedures requiring general anesthesia. To date, there has been no effective treatment to mitigate the potential neurotoxic effects of general anesthesia.
Dr. Pei-Jung Lin[/caption]
Pei-Jung Lin, Ph.D.
Assistant Professor
Center for the Evaluation of Value and Risk in Health
Institute for Clinical Research and Health Policy Studies
Tufts Medical Center
Boston, MA 02111
MedicalResearch.com: What is the background for this study? What are the main findings?
Response: Alzheimer’s disease (AD) is a slow, progressive disease. Many people with AD may live for years with the disease left unrecognized or untreated, in part because the early symptoms are mild and often mistaken as part of normal aging. In this study, we found that Alzheimer’s patients may use more health care services and incur higher costs than those without dementia even before they receive a formal diagnosis. For example, total Medicare expenditures were 42% higher among Alzheimer’s patients than matched controls during the year prior to diagnosis ($15,091 vs. $10,622), and 192% higher in the first year immediately following diagnosis ($27,126 vs. $9,274). We also found similar trends among Medicare patients with mild cognitive impairment (MCI)— a prodromal stage of AD and associated with higher dementia risk.
Our study suggests that an Alzheimer’s disease or MCI diagnosis appears to be prompted by other health problems such as cardiovascular and cerebrovascular diseases, pneumonia, renal failure, urinary tract infections, and blood and respiratory infections. This finding likely reflects a failure of ambulatory care related to the impact of cognitive impairment on other chronic conditions.
Dr. Sirry Alang[/caption]
Sirry Alang PhD
Assistant professor of sociology and anthropology
Lehigh University
MedicalResearch.com: What is the background for this study? What are the main findings?
Response: Discrepancies exist between how some Black populations perceive depression and how depression is conceptualized within research and clinical settings. African Americans are exposed to a lot of stress from structural racism, yet, they perceive themselves to be resilient. The context of stress from discrimination and beliefs about depression inform how they express psychological distress. Depression is thought of as a weakness that is inconsistent with notions of strength in the community. Although depression was expressed through classic depressive symptoms such as feeling hopeless, loss of sleep, and losing interests in activities, symptom like anger, agitation, and the frantic need for human interaction were considered to be indicative of depression. Anger, agitation, and the frantic need for human interaction are not consistent with how depression is defined in the latest manual for psychiatric diagnosis- the DSM-V.
Dr. Brian Haas[/caption]
Brian W. Haas PhD
Department of Psychology
Interdisciplinary Neuroscience Graduate Program
University of Georgia, Athens, GA
MedicalResearch.com: What is the background for this study?
Response: A burgeoning body of evidence highlights the role of several key genes within the oxytocin signaling pathway linked to sociability. Although many studies strongly supports the role of OXTR in the phenotypic expression of sociability in humans, the roles of other oxytocin pathway genes, such asOXT, has received relatively little attention.
Dr. Luca Passamonti[/caption]
MedicalResearch.com Interview with:
Dr. Luca Passamonti MD
Department of Clinical Neurosciences
University of Cambridge
MedicalResearch.com: What is the background for this study?
Dr. Passamonti: We wanted to study if the brain of young people with two different forms of conduct disorder (CD) (https://en.wikipedia.org/wiki/Conduct_disorder), a neuropsychiatric disease associated with severe and persistent antisocial behaviors (weapon use, aggression, fire-setting, stealing, fraudulent behavior), was different from that of young peers with no such abnormal behaviors.
There is already evidence that conduct disorder may have a biological basis (i.e., reduced levels of cortisol under stress) and brain alterations but a whole “map” of the brain in conduct disorder studying cortical thickness was never been done before.
Dr. Mari Videman[/caption]
Mari Videman
Senior Consultant in Child Neurology
BABA Center
Children’s Hospital, Helsinki University Hospital
MedicalResearch.com: What is the background for this study? What are the main findings?
Response: Depression and anxiety are common during pregnancy, and up to 5% of all pregnant women are treated with serotonin uptake inhibitors (SRI). It is now known that SRIs do not cause major malformations in humans, however recent animal studies have suggested that fetal early SRI exposure may cause changes in brain microstructure and neuronal signaling. Prior human studies have shown that fetal SRI exposure leads to transient postnatal adaptation syndrome, as well as to an increased risk of developing childhood depression.
We used electroencephalography (EEG) and advanced computational methods to assess both the local and global cortical function of the newborn brain. We found that several aspects of newborn brain activity are affected by exposuse to SRI during pregnancy. Most importantly, the communication between brain hemispheres, and the synchronization between cortical rhythms were weaker in the SRI-exposed newborns. These changes were most likely related to SRI exposure, because they did not correlate with the psychiatric symptoms of the mothers.
Dr. Kate Merritt[/caption]
Kate Merritt PhD
Post-Doctoral Research Worker
NOC Study (Nitric Oxide in Cognition)
Institute of Psychiatry
De Crespigny Park
London
MedicalResearch.com: What is the background for this study? What are the main findings?
Dr. Merritt: Research has indicated that levels of one of the main chemicals in the brain, glutamate, may be abnormal in schizophrenia. Almost sixty studies have measured glutamate levels in schizophrenia, however the findings are inconsistent, and it is thought that changes in glutamate levels may vary with the length or the severity of illness. This study therefore analysed all the published reports of glutamate in schizophrenia.
The main findings are that, overall, schizophrenia is associated with elevated glutamate in several brain regions; namely the medial temporal cortex, the basal ganglia and the thalamus. These changes also differed with the stage of illness; in the medial frontal cortex, glutamate was increased in people at risk for developing schizophrenia, but not in people who had been diagnosed with schizophrenia for several years, whereas in the medial temporal lobe the opposite pattern was detected.
Dr. Anna Alkozei[/caption]
Anna Alkozei, Ph.D.
Postdoctoral Research Fellow
SCAN Lab, Psychiatry Department
University of Arizona
Tucson, AZ 85724-5002
MedicalResearch.com: What is the background for this study? What are the main findings?
Dr. Alkozei: We know that exposure to blue wavelength light, which is similar to the kind of light that we get on a bright sunny day, can improve attention and alertness during the day as well as at night. We wanted to extend previous findings by investigating whether blue light exposure can affect cognitive functioning after the blue light exposure period had already ended. We found that thirty minutes of exposure to blue wavelength light during the day, in comparison to an amber light exposure led to subsequently faster reaction times on a cognitive task forty minutes after the light exposure had already ended. Participants who were exposed to blue light also showed more efficient responding, which means they answered more items correctly per second, than individuals who were exposed to amber placebo light. Finally, we also found that individuals who were exposed to blue light showed greater activation within the prefrontal cortex when performing the task, an area necessary for optimal cognitive performance, than individuals who were exposed to amber light.