New research explores role of serotonin

Findings provide insight into clinical disorders characterised by low serotonin level, such as depression, obsessive compulsive disorder and severe anxiety

New research by scientists at the University of Cambridge suggests that the neurotransmitter serotonin, which acts as a chemical messenger between nerve cells, plays a critical role in regulating emotions such as aggression during social decision-making.

Serotonin has long been associated with social behaviour, but its precise involvement in impulsive aggression has been controversial. Though many have hypothesised the link between serotonin and impulsivity, this is one of the first studies to show a causal link between the two.

Their findings highlight why some of us may become combative or aggressive when we haven't eaten. The essential amino acid necessary for the body to create serotonin can only be obtained through diet. Therefore, our serotonin levels naturally decline when we don't eat, an effect the researchers took advantage of in their experimental technique.

The research also provides insight into clinical disorders characterised by low serotonin levels, such as depression and obsessive compulsive disorder (OCD), and may help explain some of the social difficulties associated with these disorders.

This research, funded by the Wellcome Trust and the Medical Research Council, suggests that patients with depression and anxiety disorders may benefit from therapies that teach them strategies for regulating emotions during decision making, particularly in social scenarios.

READ MORE @ EUREKALERT

NIH study reveals incidence, precursors and psychiatric sequelae of major psychiatric disorders

A new study by the National Institute on Alcohol Abuse and Alcoholism (NIAAA) presents results on the first onset of substance use disorders (i.e., alcohol and drug abuse and dependence) and major mood and anxiety disorders, based on Wave 2 of the National Epidemiologic Survey on Alcohol and Related Conditions (NESARC).

This landmark survey is the first conducted in the U.S. to identify rates of first episodes (i.e., incidence) of these disorders in the U.S. population. In addition, it provides information on sociodemographic and psychopathologic risk factors for those disorders—information critical for developing evidence-based preventive interventions—and estimates risk for subsequent comorbid disorders.

Bridget Grant, Ph.D., Chief of NIAAA’s Laboratory of Biometry and Epidemiology, and her colleagues found that 1-year incidence rates were highest for DSM-IV alcohol dependence (1.70%), alcohol abuse (1.02%), major depressive disorder (1.51%) and generalized anxiety disorder (1.12%), followed by panic disorder (0.62%), bipolar I disorder (0.53%) and specific phobia (0.44%). One-year incidence rates of DSM-IV social phobia (0.32%), bipolar II (0.21%) and drug abuse (0.28%) and drug dependence (0.32%) were lower but not insignificant. These rates are comparable to or exceed corresponding incidence rates for other common medical diseases such as lung cancer (0.06%), stroke (0.45%) and cardiovascular disease (1.5%).

READ MORE @ EUREKALERT

Antipsychotics in the Treatment of Comorbid Anxiety in Bipolar Disorder

The comorbidity of anxiety disorders with bipolar disorder is a rule, not an exception, with a negative impact on both course and treatment outcome. So far, there are no guidelines or consensus for the treatment of this comorbidity. There are also no efficacy data that support the use of antidepressants or benzodiazepines in the treatment of anxiety disorder in this population. Benzodiazepines, the second-line agents for some primary anxiety disorders, may be riskier for patients with bipolar disorder because they are associated with a high rate of comorbid substance use disorder. Some preliminary data have shown that antipsychotics, especially atypical anti- psychotics, may be a viable alternative for patients with comorbid bipolar and anxiety disorders with or without substance use disorder.

READ MORE @ PSYCHIATRIC TIMES