Depression and Underperformance Syndrome: Is There a Common Denominator?

by Mimi Winsberg, M.D.

In recent psychiatric news, a new blood test may accurately determine whether a person is depressed.

The study, published in Molecular Psychiatry, was conducted at Massachusetts General Hospital in Boston, and used a new multi-assay diagnostic blood test to achieve a highly sensitive measure for distinguishing patients with clinical depression from healthy peers. Up until now no reliable biological markers have existed to identify depression.

The biologic markers measured in the blood test came from four biochemical domains: inflammation, the hypothalamic-pituitary adrenal axis which controls the release of cortisol (stress hormone), key growth factors and metabolism. Interestingly, these are some of the same domains that are affected with underperformance syndrome. So some of the biological changes associated with underperformance syndrome also seem to be present in depression.

How is underperformance syndrome (also know as overtraining syndrome) understood? While aerobic exercise is generally healthy and can alleviate many psychiatric illnesses including depression, training for extensive periods of time can lead to unhealthy levels of stress and inflammation.

Training stress typically induces fatigue and decreased functioning, but with rest, compensation occurs and the body gets stronger. Underperformance syndrome is defined as a lack of performance rebound after a two week period of relative rest. With underperformance syndrome athletes may experience both physical and psychological symptoms including increased tension, depressed mood, anger and fatigue. Additionally they can experience disturbed sleep, decreased motivation, reduced ability to experience pleasure and decreased appetite.

A strikingly similar checklist of symptoms is used by psychiatrists to screen for clinical depression. As with underperformance syndrome, clinical depression can be diagnosed when symptoms have lasted for two weeks or longer.

Biological markers associated with symptoms of overtraining include decreased testosterone/ cortisol ratios, decreased glycogen stores, and decreased serotonin levels. Serotonin is a neurotransmitter known to modulate mood, and play a role in central fatigue, lethargy and sleep. Serotonin levels are thought be disrupted in depression and are often targeted with anti-depressant medications.

Perhaps there is a final common pathway between underperformance syndrome and depression that involves stress and inflammation due to excessive cortisol release. Distinguishing the two clinical states in an athlete can in fact be tricky, though with overtraining/underperformance, the athlete typically continues to have the urge to train, whereas with depression that desire can extinguish. Athletes are usually reluctant to admit to the possibility of overtraining, let alone the possibility of depression. There is an ethic of mental toughness in endurance sports that can stigmatize depression or fatigue.

Some psychiatrists are welcoming the possibility of a blood test to screen for depression, as it would free patients from viewing their illness as a character flaw or weakness.

Perhaps there are endurance athletes who could benefit from a biologic screen for underperformance syndrome and spare themselves a vicious cycle of fatigue, exhaustion and attempt at overcompensation.

How many times have you heard an athlete ask: "Am I tired or just being a wimp?" Maybe in the future athletes will just need to submit to a blood test to know when enough is really enough.

Tune in to next week’s IMTalk to hear John’s and Bevan’s interview with Mimi on “Depression and the Endurance Athlete.”

Mimi is a psychiatrist and multiple-time Kona qualifier. You can contact her at m.winsberg@gmail.com.