Treating Depression: Is there a placebo effect?

A Harvard scientist says the drugs used to treat depression are effective, but for many, it’s the placebo effect that’s making people feel better. 

Do antidepressants work? Since the introduction of Prozac in the 1980s, prescriptions for antidepressants have soared 400 percent, with 17 million Americans currently taking some form of the drug. But how much good is the medication itself doing? “The difference between the effect of a placebo and the effect of an antidepressant is minimal for most people,” says Harvard scientist Irving Kirsch. Will Kirsch’s research, and the work of others, change the USD 11.3 billion antidepressant industry? Lesley Stahl investigates (CBS News, 2012).

 

First blood test to diagnose major depression in teens

Breakthrough test identifies depression and its subtypes with promise of individualized treatment

CHICAGO — A Northwestern Medicine scientist has developed the first blood test to diagnose major depression in teens, a breakthrough approach that allows an objective diagnosis by measuring a specific set of markers found in a patient’s blood.

The current method of diagnosing depression is subjective. It relies on the patient’s ability to recount his symptoms and the physician’s ability and training to interpret them.

Diagnosing teens is an urgent concern because they are highly vulnerable to depression and difficult to accurately diagnose due to normal mood changes during this age period.

The test also is the first to identify subtypes of depression. It distinguished between teens with major depression and those with major depression combined with anxiety disorder. This is the first evidence that it’s possible to diagnose subtypes of depression from blood, raising the hope for tailoring care to the different types.

“Right now depression is treated with a blunt instrument,” said Eva Redei, a professor of psychiatry and behavioral sciences at Northwestern University Feinberg School of Medicine and lead investigator of the study, published in Translational Psychiatry. “It’s like treating type 1 diabetes and type 2 diabetes exactly the same way. We need to do better for these kids.”

“This is the first significant step for us to understand which treatment will be most effective for an individual patient,” added Redei, also the David Lawrence Stein Professor of Psychiatric Diseases Affecting Children and Adolescents. “Without an objective diagnosis, it’s very difficult to make that assessment. The early diagnosis and specific classification of early major depression could lead to a larger repertoire of more effective treatments and enhanced individualized care.”

The estimated rates of major depressive disorder jump from 2 to 4 percent in pre-adolescent children to 10 to 20 percent by late adolescence. Early onset of major depression in teens has a poorer prognosis than when it starts in adulthood. Untreated teens with this disease experience increases in substance abuse, social maladjustment, physical illness and suicide. Their normal development is derailed, and the disease persists into adulthood.

The depressed teens in the study were patients of Kathleen Pajer, M.D., a co-first author of the study, and her colleagues from the Research Institute of Nationwide Children’s Hospital in Columbus, Ohio. Pajer is now head of Dalhousie University’s division of child and adolescent psychiatry in Nova Scotia, Canada.

The study subjects included 14 adolescents with major depression who had not been clinically treated and 14 non-depressed adolescents, all between 15 to 19 years old. The depressed and control subjects were matched by sex and race.

Redei’s lab tested the adolescents’ blood for 26 genetic blood markers she had identified in previous research. She discovered 11 of the markers were able to differentiate between depressed and non-depressed adolescents. In addition, 18 of the 26 markers distinguished between patients that had only major depression and those who had major depression combined with anxiety disorder.

The blood analysis was done by Brian Andrus from Redei’s lab, the other co-first author of the study, who was blind to the diagnoses of the subjects.

“These 11 genes are probably the tip of the iceberg because depression is a complex illness,” Redei said. “But it’s an entree into a much bigger phenomenon that has to be explored. It clearly indicates we can diagnose from blood and create a blood diagnosis test for depression.”

Redei first isolated and identified the genetic blood markers for depression and anxiety based on decades of research with severely depressed and anxious rats. The rats mirror many behavioral and physiological abnormalities found in patients with major depression and anxiety.

Further indicating the challenge in working with depressed adolescents, none of the teens who were diagnosed with depression opted for treatment.

“Everybody, including parents, are wary of treatment, and there remains a social stigma around depression, which in the peer-pressured world of teenagers is even more devastating,” Redei said. “Once you can objectively diagnose depression as you would hypertension or diabetes, the stigma will likely disappear.”

 

Reference

Pajer K, Andrus BM, Gardner W, Lourie A, Strange B, Campo J, Bridge J, Blizinsky K, Dennis K, Vedell P, Churchill GA, Redei EE. Discovery of blood transcriptomic markers for depression in animal models and pilot validation in subjects with early-onset major depression. Transl Psychiatry (2012) 2, e101. DOI: 10.1038/tp.2012.26

 

The Link Between Fast Food and Depression Has Been Confirmed

According to a recent study headed by scientists from the University of Las Palmas de Gran Canaria and the University of Granada, eating commercial baked goods (fairy cakes, croissants, doughnuts, etc.) and fast food (hamburgers, hotdogs and pizza) is linked to depression.

Published in the Public Health Nutrition journal, the results reveal that consumers of fast food, compared to those who eat little or none, are 51% more likely to develop depression.

Furthermore, a dose-response relationship was observed. In other words this means that “the more fast food you consume, the greater the risk of depression,” explains Almudena Sánchez-Villegas, lead author of the study, to SINC.

The study demonstrates that those participants who eat the most fast food and commercial baked goods are more likely to be single, less active and have poor dietary habits, which include eating less fruit, nuts, fish, vegetables and olive oil. Smoking and working more than 45 hours per week are other prevalent characteristics of this group.

A long-term study

With regard to the consumption of commercial baked goods, the results are equally conclusive. “Even eating small quantities is linked to a significantly higher chance of developing depression,” as the university researcher from the Canary Islands points out.

The study sample belonged to the SUN Project (University of Navarra Diet and Lifestyle Tracking Program). It consisted of 8,964 participants that had never been diagnosed with depression or taken antidepressants. They were assessed for an average of six months, and 493 were diagnosed with depression or started to take antidepressants.

This new data supports the results of the SUN project in 2011, which were published in the PLoS One journal. The project recorded 657 new cases of depression out of the 12,059 people analysed over more than six months. A 42% increase in the risk associated with fast food was found, which is lower than that found in the current study.

Sánchez-Villegas concludes that “although more studies are necessary, the intake of this type of food should be controlled because of its implications on both health (obesity, cardiovascular diseases) and mental well-being.”

The impact of diet on mental health

Depression affects 121 million people worldwide. This figure makes it one of the main global causes of disability-adjusted life year. Further still, in countries with low and medium income it is the leading cause.

However, little is known about the role that diet plays in developing depressive disorders. Previous studies suggest that certain nutrients have a preventative role. These include group B vitamins, omega-3 fatty acids and olive oil. Furthermore, a healthy diet such as that enjoyed in the Mediterranean has been linked to a lower risk of developing depression.

 

Reference

Sánchez-Villegas A, Toledo E, de Irala J, Ruiz-Canela M, Pla-Vidal J, Martínez-González MA. Fast-food and commercial baked goods consumption and the risk of depression. Public Health Nutr 2012; 15 (3): 424-32.

 

Mercury Toxicity Presenting as Chronic Fatigue, Memory Impairment and Depression

In a group of 465 patients diagnosed as having chronic mercury toxicity (CMT), 32.3% had severe fatigue, 88.8% had memory loss, and 27.5% had depression. A significant correlation was found between CMT and the Apo-lipoprotein E4 genotype (p=0.001). An investigation into an additional 864 consecutively seen general practice patients, resulted in 30.3% having evidence consistent with CMT, and once again a significant correlation was found with the APO-E4 genotype (p=0.001). Removal of amalgam mercury fillings when combined with appropriate treatment resulted in a significant symptom reduction (p<0.001) to levels reported by healthy subjects.


Reference

Wojcik DP, Godfrey ME, Christie D, Haley BE. Mercury toxicity presenting as chronic fatigue, memory impairment and depression: diagnosis, treatment, susceptibility, and outcomes in a New Zealand general practice setting (1994-2006). Neuro Endocrinol Lett. 2006; 27 (4): 415-23.