The discovery of chemical neurotransmitters

Neurotransmitters have become such an intrinsic part of our theories about brain function that many today are unaware of how difficult it was to prove their existence or the protracted dispute over the nature of synaptic transmission. The story is important not only because it is fascinating science history, but also because it exemplifies much of what is best in science and deserving to be emulated. The friendships formed among such major figures in this history as Henry Dale, Otto Loewi, Wilhelm Feldberg, Walter Cannon, and others extended over two world wars, enriching their lives and facilitating their research. Even the dispute-the "war of the sparks and the soups"--between neurophysiologists and pharmacologists over whether synaptic transmission is electrical or chemical played a positive role in stimulating the research needed to provide convincing proof.     

Treatment‐Resistant Depression and Risk of Suicide

We evaluated whether treatment‐resistant depression (TRD) as measured by the Massachusetts General Hospital (MGH) staging method was associated with suicide in a large U.S. health system. Data from the Veterans Health Administration and the National Death Index were used to conduct a case–control study of patients newly diagnosed with depression who received antidepressant treatment between 2003 and 2006. Suicide cases (N = 499) were matched with nonsuicide controls (N = 1994). Conditional logistic regression was used to assess whether MGH stage at time of suicide (or matched date) was associated with case status, adjusting for patient demographic characteristics, comorbidity, and service use. Results indicated 11.6% of suicide cases had MGH stage 3 or greater (indicating at least two antidepressant trials) compared to 6.4% of controls (p < .001). In adjusted analyses, suicide was not significantly more likely among patients with stage 3 or greater (OR 1.52; 95% CI: 0.98, 2.37) or stages 1.5–2.5 (OR 1.19; 95% CI: 0.91, 1.55) compared to patients with stage 1 or less (<10 weeks of antidepressant medication). Staging TRD using MGH criteria is unlikely to substantially improve suicide risk assessment of depressed patients beyond existing measures contained in health system records.     

Postdeployment Suicide Risk Increases Over a 6‐month Period: Predictors of Increased Risk among Midwestern Army National Guard Soldiers

National Guard (NG) soldiers returning from deployments in Iraq and Afghanistan were surveyed at 6 and 12 months following their return (N = 970). The overall prevalence of suicide risk at 6 and 12 months following their return was assessed, as were changes in suicide risk among soldiers initially at high or low risk. Factors associated with changes in risk were assessed. The percentage of NG soldiers with high suicide risk increased from 6.8% at 6 months to 9.2% at 12 months (odds ratio = 1.7, p = .02). In the 882 soldiers initially at low risk, 5.9% (52/882) became high risk at 12 months; in the 64 soldiers initially at high risk, 46.9% (30/64) became low risk at 12 months. Initial levels of depressive symptoms were predictive of changing to high risk; this association appeared to be partially explained by soldier reports of increased search in the meaning in life and higher levels of perceived stress. Because suicide risk increases over the first 12 months, continued risk assessments during this time period should be considered. Supporting soldiers to find meaning in their life after deployment and enhancing their capacity to cope with perceived stress may help prevent increases in suicide risk over time.